@article {79380, title = {Carbon{\textendash}Mercury Interactions in Spodosols Assessed through Density Fractionation, Radiocarbon Analysis, and Soil Survey Information}, journal = {Soil Science Society of America Journal}, volume = {83}, year = {2019}, month = {Jan-01-2019}, pages = {190}, doi = {10.2136/sssaj2018.06.0227}, url = {https://dl.sciencesocieties.org/publications/sssaj/abstracts/83/1/190https://dl.sciencesocieties.org/publications/sssaj/pdfs/83/1/190}, author = {Nave, L.E. and Covarrubias Ornelas, A. and Drevnick, P.E. and Gallo, A. and Hatten, J.A. and Heckman, K.A. and Matosziuk, L. and Sanclements, M. and Strahm, B.D. and Veverica, T.J. and Weiglein, T.L. and Swanston, C.W.} } @article {79376, title = {A national approach to leverage the benefits of tree planting on public lands}, journal = {New Forests}, volume = {50}, year = {2019}, month = {Jan-01-2019}, pages = {1 - 9}, issn = {0169-4286}, doi = {10.1007/s11056-019-09703-2}, url = {https://doi.org/10.1007/s11056-019-09703-2}, author = {Dumroese, R. Kasten and Balloffet, Nicole and Crockett, John W. and Stanturf, John A. and Nave, Lucas E.} } @article {79378, title = {Seasonal dynamics and exports of elements from a first-order stream to a large inland lake in Michigan}, journal = {Hydrological Processes}, year = {2019}, month = {Jun-03-2020}, issn = {0885-6087}, doi = {10.1002/hyp.13416}, url = {https://doi.org/10.1002/hyp.13416}, author = {Hofmeister, Kathryn L. and Nave, Lucas E. and Drevnick, Paul and Veverica, Timothy and Knudstrup, Renee and Heckman, Katherine A. and Riha, Susan J. and Schneider, Rebecca L. and Walter, M. Todd} } @article {79306, title = {An omnipresent diversity and variability in the chemical composition of atmospheric functionalized organic aerosol}, journal = {Communications Chemistry}, year = {2018}, month = {Jan-12-2018}, abstract = {The atmospheric evolution of organic compounds encompasses many thousands of compounds with varying volatility, polarity, and water solubility. The molecular-level chemical composition of this mixture plays a major, yet uncertain, role in its transformations and impacts. Here we perform a non-targeted molecular-level intercomparison of functionalized organic aerosol from three diverse field sites and a chamber. Despite similar bulk composition, we report large molecular-level variability between multi-hour organic aerosol samples at each site, with 66 {\textpm} 13\% of functionalized compounds differing between consecutive samples. Single precursor environmental laboratory chamber experiments and fully chemically-explicit modeling confirm this variability is due to changes in emitted precursors, chemical age, and/or oxidation conditions. These molecular-level results demonstrate greater compositional variability than is typically observed in less-speciated measurements, such as bulk elemental composition, which tend to show less daily variability. These observations should inform future field and laboratory studies, including assessments of the effects of variability on aerosol properties and ultimately the development of strategic organic aerosol parameterizations for air quality and climate models.}, keywords = {organic aerosols}, doi = {10.1038/s42004-018-0074-3}, url = {http://www.nature.com/articles/s42004-018-0074-3http://www.nature.com/articles/s42004-018-0074-3.pdfhttp://www.nature.com/articles/s42004-018-0074-3.pdfhttp://www.nature.com/articles/s42004-018-0074-3}, author = {Ditto, Jenna C. and Barnes, Emily B. and Khare, Peeyush and Takeuchi, Masayuki and Joo, Taekyu and Bui, Alexander A. T. and Lee-Taylor, Julia and Eris, Gamze and Chen, Yunle and Aumont, Bernard and Jimenez, Jose L. and Ng, Nga Lee and Griffin, Robert J. and Gentner, Drew R.} } @article {78937, title = {Shifting conceptions of complexity in forest management and silviculture}, journal = {Forest Ecology and Management}, year = {2018}, month = {Jan-02-2018}, abstract = {In the past several decades, a trend in forestry and silviculture has been toward promoting complexity in forest ecosystems, but how complexity is conceived and described has shifted over time as new ideas and terminology have been introduced. Historically, ecologically-focused silviculture has focused largely on manipulation of structural complexity, but often with the functional role of features in mind. Recently there has been a shift toward viewing complexity in an {\textquotedblleft}adaptive{\textquotedblright} or {\textquotedblleft}resilience{\textquotedblright} context, with a focus on understanding forests as complex adaptive systems. As new concepts and terminology are introduced it will be essential that silviculture researchers understand their dissemination into silviculture research, experimental design, and treatment implementation. With this goal in mind we set out to better understand: (1) how complexity terminology and ideas have shifted over time in silviculture, (2) how different conceptions of complexity have been incorporated into silviculture experiments and treatments, and (3) how various complexity concepts are being reconciled with each other in practice. We conducted a multi-stage review of the silvicultural literature for the time period 1992{\textendash}2017 that included: (1) a broad keyword analysis, (2) a detailed review of a narrower subset of publications, and (3) a thorough review of a set of silvicultural experiments that included a focus on complexity in their design. We also developed a set of case studies that illustrate shifts in complexity conceptions in silvicultural experiment design and analysis. Our analysis indicates considerable lags in incorporation of complexity-focused terminology and ideas into silvicultural research and experimental treatment design. Very few silviculture-focused studies have incorporated adaptive complexity concepts explicitly into design or analysis, even though these concepts were introduced nearly a decade ago and are widely discussed in the literature. However, in our case studies we document how silviculture experiments and research programs that were not designed explicitly around complexity concepts have begun to incorporate these ideas into analysis of treatment outcomes. Silviculture researchers should focus on reconciling conceptions of complexity through analysis of existing experiments and with modeling studies, as well as attempting to better understand mechanistic relationships among structural, functional, and adaptive conceptions of complexity.}, issn = {03781127}, doi = {10.1016/j.foreco.2018.01.011}, url = {http://linkinghub.elsevier.com/retrieve/pii/S0378112717316511http://api.elsevier.com/content/article/PII:S0378112717316511?httpAccept=text/xmlhttp://api.elsevier.com/content/article/PII:S0378112717316511?httpAccept=text/plain}, author = {Fahey, Robert T. and Alveshere, Brandon C. and Burton, Julia I. and D{\textquoteright}Amato, Anthony W. and Dickinson, Yvette L. and Keeton, William S. and Kern, Christel C. and Larson, Andrew J. and Palik, Brian J. and Puettmann, Klaus J. and Saunders, Michael R. and Webster, Christopher R. and Atkins, Jeff W. and Gough, Christopher M. and Hardiman, Brady S.} } @article {79327, title = {Coupling Fine-Scale Root and Canopy Structure Using Ground-Based Remote Sensing}, journal = {Remote Sensing}, volume = {920155}, year = {2017}, month = {Jan-02-2017}, pages = {182}, abstract = {Ecosystem physical structure, defined by the quantity and spatial distribution of biomass, influences a range of ecosystem functions. Remote sensing tools permit the non-destructive characterization of canopy and root features, potentially providing opportunities to link above- and belowground structure at fine spatial resolution in functionally meaningful ways. To test this possibility, we employed ground-based portable canopy LiDAR (PCL) and ground penetrating radar (GPR) along co-located transects in forested sites spanning multiple stages of ecosystem development and, consequently, of structural complexity. We examined canopy and root structural data for coherence (i.e., correlation in the frequency of spatial variation) at multiple spatial scales <=10 m within each site using wavelet analysis. Forest sites varied substantially in vertical canopy and root structure, with leaf area index and root mass more becoming even vertically as forests aged. In all sites, above- and belowground structure, characterized as mean maximum canopy height and root mass, exhibited significant coherence at a scale of 3.5{\textendash}4 m, and results suggest that the scale of coherence may increase with stand age. Our findings demonstrate that canopy and root structure are linked at characteristic spatial scales, which provides the basis to optimize scales of observation. Our study highlights the potential, and limitations, for fusing LiDAR and radar technologies to quantitatively couple above- and belowground ecosystem structure.}, doi = {10.3390/rs9020182}, url = {http://www.mdpi.com/2072-4292/9/2/182http://www.mdpi.com/2072-4292/9/2/182/pdf}, author = {Hardiman, Brady and Gough, Christopher and Butnor, John and Bohrer, Gil and Detto, Matteo and Curtis, Peter} } @article {74122, title = {Physiographic factors underlie rates of biomass production during succession in Great Lakes forest landscapes}, journal = {Forest Ecology and Management}, volume = {397}, year = {2017}, month = {Jan-08-2017}, pages = {157 - 173}, abstract = {Biomass production in living trees is the basis of numerous forest ecosystem functions and services. However, rates of and controls on biomass production vary widely across temperate forests, particularly over successional timescales of decades and centuries. Biomass production in temperate forests is most often interpreted within the context of biotic or top-down controls, such as species composition or disturbance. However, there is need to investigate how bottom-up physiographic factors, such as landform attributes, drainage, and soil properties mediate biomass production. In order to investigate patterns, controls, and potentials for biomass production across spatial levels ranging from individual ecosystems, to landscapes, to entire regions, we synthesized long-term forest inventory datasets from the United States Great Lakes region, placed them in the context of a hierarchical ecological unit classification, and tested the influence of physiographic factors on biomass production rates and temporal trajectories across ecological levels. Key findings include: 1) At nearly all ecological levels, physiographic controls (e.g., soil texture, drainage class, water table depth) on soil moisture status are significant predictors of variation in biomass production rates, with mesic sites accumulating biomass more rapidly than xeric sites, which, in turn accumulate biomass more rapidly than hydric sites. 2) Aboveground live biomass can apparently continue to accumulate through 2{\textendash}3 centuries of succession, exceeding 300{\textendash}400 Mg ha-1 on mesic sites throughout the region. 3) Stand age distributions indicate that hydric sites are harvested least often, while the high production rates of mesic sites suggest they are most appropriate for frequent harvesting. 4) Median, 1st-quartile, and 3rd-quartile growth rates of individual ecosystems, landscapes, and ecoregional subsections and sections reveal ecological units in which forests may vary in their potential for increases or decreases in biomass production, e.g., due to management interventions, climate change, or disturbances. Specifically, some units have tightly constrained distributions, suggesting little capacity for change in production rates relative to observed medians, while other units have wide variation in biomass production rates, indicating the potential for relatively large increases or decreases in production. Altogether, the results of this analysis show that physiography exerts widespread, bottom-up controls on biomass production across the region of study, and can be used in spatially explicit frameworks to understand ecosystem functioning and inform scientific forest management.}, keywords = {Ecosystem classification, Landform, Natural drainage, Soil moisture status, Soil texture}, issn = {03781127}, doi = {10.1016/j.foreco.2017.04.040}, url = {http://linkinghub.elsevier.com/retrieve/pii/S037811271730333Xhttp://api.elsevier.com/content/article/PII:S037811271730333X?httpAccept=text/plainhttp://api.elsevier.com/content/article/PII:S037811271730333X?httpAccept=text/xml}, author = {Nave, Lucas E. and Gough, Christopher M. and Perry, Charles H. and Hofmeister, Kathryn L. and Le Moine, James M. and Domke, Grant M. and Swanston, Christopher W. and Nadelhoffer, Knute J.} } @article {70051, title = {Evaluating forest subcanopy response to moderate severity disturbance and contribution to ecosystem-level productivity and resilience}, journal = {Forest Ecology and Management}, volume = {376}, year = {2016}, note = {Dept. of Energy}, month = {09/2016}, pages = {135 - 147}, type = {PI}, abstract = {North American temperate forests have functioned as a terrestrial carbon (C) sink for more than a century, but the future of this sink is highly uncertain as disturbance frequency increases and regrown forests approach maturity. The subcanopy is integral to the functional recovery of forests, supporting short-term resilience of primary production and longer-term shifts in tree species composition and diversity. However, the factors that contribute to variation in forest subcanopy response to disturbance are not well understood. In this study, we investigated subcanopy shifts in aboveground wood net primary productivity (ANPPw) and composition following experimental moderate severity disturbance emulating natural canopy mortality from age-related senescence. We assessed the importance of variation in disturbance severity, site fertility, and community composition on subcanopy disturbance response and contribution to total (canopy and subcanopy) ANPPw response. We also assessed the effect of the moderate severity disturbance on species composition and diversity, and competitive patterns within the subcanopy layer. Subcanopy aboveground biomass and ANPPw increased substantially relative to pre-disturbance levels by a factor of 1.4 and 22.7, respectively. The subcanopy (stems <8 cm DBH) made up a large component of overall (canopy plus subcanopy) post disturbance ANPPw (16.2\%) and disturbance response (post-disturbance ANPPw/pre-disturbance ANPPw; 54.1\%). Subcanopy ANPPw, subcanopy post-disturbance ANPPw response, and subcanopy contribution to total post-disturbance ANPPw response were all most strongly predicted by subcanopy community composition in combination with canopy composition and site fertility. Variation in disturbance severity was not a strong predictor of subcanopy ANPPw response to disturbance. Subcanopy compositional trends and growth patterns both indicate likely increased heterogeneity in canopy composition (greater β diversity) and a potential shift toward greater dominance by mid-tolerant Quercus rubra (northern red oak). Our results illustrate the importance of the subcanopy in the response of forest productivity to moderate severity disturbance and illustrate that composition of the subcanopy layer exerts a strong influence on the growth response both of the subcanopy and the forest as a whole. Our findings highlight the unique role of moderate severity disturbance, relative to more severe disturbances, in promoting biological and structural heterogeneity in forest ecosystems and favoring underrepresented mid-tolerant species.}, keywords = {QUERCUS RUBRA}, doi = {10.1016/j.foreco.2016.06.001}, author = {Fahey, Robert T. and Stuart-Ha{\"e}ntjens, Ellen J. and Gough, Christopher M. and De La Cruz, Aubrie and Stockton, Elizabeth and Vogel, Christoph S. and Curtis, Peter S.} } @article {74151, title = {Yellow-bellied Sapsuckers ( Sphyrapicus varius) alter sap well locations in response to experimentally induced tree damage}, journal = {The Wilson Journal of Ornithology}, volume = {128}, year = {2016}, month = {Jan-09-2016}, pages = {619 - 623}, abstract = {Yellow-bellied Sapsuckers (Sphyrapicus varius) regularly use paper birch (Betula papyrifera) as a source of sap during the breeding season and may position their sap wells on the tree in order to maximize sap extraction. Sap flow can be affected by tree damage, and altering sap well locations in response to such damage could enhance sapsucker foraging efficiency. We sought to determine if sapsuckers selectively drilled sap wells on damaged (experimentally girdled) paper birch trees over non-damaged healthy trees and, if so, whether the locations of the drill sites varied in response to this damage. Sapsuckers drilled holes on a significantly larger proportion of girdled trees than control trees (healthy trees on adjacent plots), and the holes were lower on girdled trees in comparison with control trees. These differences occurred even though control and girdled trees were of similar size (diameter) and had similar numbers of sap wells per tree. Yellow-bellied Sapsuckers appear to alter their foraging behavior in response to tree damage, and thus factors affecting such damage could indirectly influence the foraging ecology of this species.}, keywords = {foraging behavior, sap wells, WOODPECKERS, Yellow-bellied Sapsuckers}, issn = {1559-4491}, doi = {10.1676/1559-4491-128.3.619}, url = {http://www.bioone.org/doi/10.1676/1559-4491-128.3.619}, author = {Dority, Delina and Price, J. Jordan and Pruett-Jones, Stephen} } @article {70070, title = {Embryotoxicity of maternally-transferred methylmercury to fathead minnows Pimephales promelas}, journal = {Environmental Toxicology and Chemistry}, year = {2015}, month = {10/2015}, abstract = {Mercury is a ubiquitous environmental contaminant and potent neurotoxin. In aquatic environments, mercury can be transformed into methylmercury (MeHg), which bioaccumulates in aquatic food webs, including fish. MeHg has been shown to transfer from female fish to developing eggs; however, relatively little is known regarding effects of maternally-transferred MeHg on fish embryos. Here, we evaluate the effects of maternally-transferred MeHg on fathead minnow (Pimephales promelas) embryos. Embryos were collected from adult fatheads exposed for 30 days to one of three diets spiked with MeHg: a control diet (0.02 ppm Hg dry weight), a low diet (0.87 ppm Hg dry weight), or a high diet (5.5 ppm Hg dry weight). No effects on spawning frequency, clutch size, or total egg output were observed. In embryos, Hg concentration was a function of female diet and the duration (number of days) of female exposure. Compared to controls, embryos from the low diet treatment displayed altered embryonic movement patterns (hyperactivity), as well as decreased time to hatch. Embryos from the high diet treatment had delayed hatching and increased mortality compared to the other treatments. Collectively, these results suggest maternally transferred mercury may impact survival, behavior, and developmental milestones of embryo-larval stages of fish.}, doi = {10.1002/etc.3282}, author = {Bridges, Kristin N. and Soulen, Brianne K. and Overturf, Carmen L. and Drevnick, Paul E. and Roberts, Aaron P.} } @article {70077, title = {Increase in mercury in Pacific yellowfin tuna}, journal = {Environmental Toxicology and Chemistry}, volume = {34}, year = {2015}, month = {04/2015}, pages = {931 - 934}, abstract = {Mercury is a toxic trace metal that can accumulate to levels that threaten human and environmental health. Models and empirical data suggest that humans are responsible for a great deal of the mercury actively cycling in the environment at present. Thus, one might predict that the concentration of mercury in fish should have increased dramatically since the Industrial Revolution. Evidence in support of this hypothesis has been hard to find, however, and some studies have suggested that analyses of fish show no change in mercury concentration. By compiling and re-analyzing published reports on yellowfin tuna (Thunnus albacares) caught near Hawaii (USA) over the past half century, the authors found that the concentration of mercury in these fish currently is increasing at a rate of at least 3.8\% per year. This rate of increase is consistent with a model of anthropogenic forcing on the mercury cycle in the North Pacific Ocean and suggests that fish mercury concentrations are keeping pace with current loading increases to the ocean. Future increases in mercury in yellowfin tuna an other fishes can be avoided by reductions in atmospheric mercury emissions from point sources.}, keywords = {MERCURY}, doi = {10.1002/etc.2883}, author = {Drevnick, Paul E. and Lamborg, Carl H. and Horgan, Martin J.} } @article {79346, title = {Isotopic study of mercury sources and transfer between a freshwater lake and adjacent forest food web}, journal = {Science of The Total Environment}, volume = {532}, year = {2015}, month = {Jan-11-2015}, pages = {220 - 229}, abstract = {Studies of monomethylmercury (MMHg) sources and biogeochemical pathways have been extensive in aquatic ecosystems, but limited in forest ecosystems. Increasing evidence suggests that there is significant mercury (Hg) exchange between aquatic and forest ecosystems. We use Hg stable isotope ratios (δ202Hg and Δ199Hg) to investigate the relative importance of MMHg sources and assess Hg transfer pathways between Douglas Lake and adjacent forests located at the University of Michigan Biological Station, USA. We characterize Hg isotopic compositions of basal resources and use linear regression of \% MMHg versus δ202Hg and Δ199Hg to estimate Hg isotope values for inorganic mercury (IHg) and MMHg in the aquatic and adjacent forest food webs. In the aquatic ecosystem, we found that lake sediment represents a mixture of IHg pools deposited via watershed runoff and precipitation. The δ202Hg and Δ199Hg values estimated for IHg are consistent with other studies that measured forest floor in temperate forests. The Δ199Hg value estimated for MMHg in the aquatic food web indicates that MMHg is subjected to ~20\% photochemical degradation prior to bioaccumulation. In the forest ecosystem, we found a significant negative relationship between total Hg and δ202Hg and Δ199Hg of soil collected at multiple distances from the lakeshore and lake sediment. This suggests that IHg input from watershed runoff provides an important Hg transfer pathway between the forest and aquatic ecosystems. We measured Δ199Hg values for high trophic level insects and compared these insects at multiple distances perpendicular to the lake shoreline. The Δ199Hg values correspond to the \% canopy cover suggesting that forest MMHg is subjected to varying extents of photochemical degradation and the extent may be controlled by sunlight. Our study demonstrates that the use of Hg isotopes adds important new insight into the relative importance of MMHg sources and complex Hg transfer pathways across ecosystem boundaries.}, keywords = {emergent insects, Food webs, FORESTS, Lakes, Mercury stable isotopes, Methylmercury}, issn = {00489697}, doi = {10.1016/j.scitotenv.2015.06.012}, url = {https://linkinghub.elsevier.com/retrieve/pii/S0048969715302060https://api.elsevier.com/content/article/PII:S0048969715302060?httpAccept=text/xmlhttps://api.elsevier.com/content/article/PII:S0048969715302060?httpAccept=text/plain}, author = {Kwon, Sae Yun and Blum, Joel D. and Nadelhoffer, Knute J. and Timothy Dvonch, J. and Tsui, Martin Tsz-Ki} } @article {70083, title = {Joint control of terrestrial gross primary productivity by plant phenology and physiology}, journal = {Proceedings of the National Academy of Sciences}, year = {2015}, note = {DOE, NSF}, month = {02/2015}, pages = {201413090}, type = {PI}, abstract = {Terrestrial gross primary productivity (GPP) varies greatly over time and space. A better understanding of this variability is necessary for more accurate predictions of the future climate{\textendash}carbon cycle feedback. Recent studies have suggested that variability in GPP is driven by a broad range of biotic and abiotic factors operating mainly through changes in vegetation phenology and physiological processes. However, it is still unclear how plant phenology and physiology can be integrated to explain the spatiotemporal variability of terrestrial GPP. Based on analyses of eddy{\textendash}covariance and satellite-derived data, we decomposed annual terrestrial GPP into the length of the CO2 uptake period (CUP) and the seasonal maximal capacity of CO2 uptake (GPPmax). The product of CUP and GPPmax explained >90\% of the temporal GPP variability in most areas of North America during 2000{\textendash}2010 and the spatial GPP variation among globally distributed eddy flux tower sites. It also explained GPP response to the European heatwave in 2003 (r 2 = 0.90) and GPP recovery after a fire disturbance in South Dakota (r 2 = 0.88). Additional analysis of the eddy{\textendash}covariance flux data shows that the interbiome variation in annual GPP is better explained by that in GPPmax than CUP. These findings indicate that terrestrial GPP is jointly controlled by ecosystem-level plant phenology and photosynthetic capacity, and greater understanding of GPPmax and CUP responses to environmental and biological variations will, thus, improve predictions of GPP over time and space.}, keywords = {SPATIOTEMPORAL VARIABILITY}, doi = {10.1073/pnas.1413090112}, author = {Xia, Jianyang and Niu, Shuli and Ciais, Philippe and Janssens, Ivan A. and Chen, Jiquan and Ammann, Christof and Arain, Altaf and Blanken, Peter D. and Cescatti, Alessandro and Bonal, Damien and Buchmann, Nina and Curtis, Peter S. and Chen, Shiping and Dong, Jinwei and Flanagan, Lawrence B and Frankenberg, Christian and Georgiadis, Teodoro and Gough, Christopher M. and Hui, Dafeng and Kiely, Gerard and Li, Jianwei and Lund, Magnus and Magliulo, Vincenzo and Marcolla, Barbara and Merbold, Lutz and Montagnani, Leonardo and Moors, Eddy J. and Olesen, J{\o}rgen E. and Piao, Shilong and Raschi, Antonio and Roupsard, Olivier and Suyker, Andrew E. and Urbaniak, Marek and Vaccari, Francesco P. and Varlagin, Andrej and Vesala, Timo and Wilkinson, Matthew and Weng, Ensheng and Wohlfahrt, Georg and Yan, Liming and Luo, Yiqi} } @article {70064, title = {The match and mismatch between photosynthesis and land surface phenology of deciduous forests}, journal = {Agricultural and Forest Meteorology}, volume = {214-215}, year = {2015}, month = {12/2015}, pages = {25 - 38}, abstract = {Plant phenology is a key indicator of the terrestrial biosphere{\textquoteright}s response to climate change, as well as a driver of global climate through changes in the carbon, energy and water cycles. Remote sensing observations of seasonal canopy greenness dynamics represent a valuable means to study land surface phenology (LSP) at scales relevant for comparison with regional climate information as well as ecosystem-level CO2 fluxes. We explore relationships among key LSP dates at the start and end of the season captured by three remote sensing products (i.e., NDVI: Normalized Difference Vegetation Index; PI: Phenology Index; MODIS Land Cover Dynamics Product based on the Enhanced Vegetation Index, EVI) over 19 deciduous broadleaf and mixed forest sites in the northern hemisphere for 2000{\textendash}2012, and compare these estimates to estimates of start and end of photosynthesis phenology extracted from gross primary productivity (GPP) from CO2 flux measurements. To derive phenological transition dates, we use analytical solutions of various derivatives from the fitted logistic curves. LSP dates estimated by the three remote sensing products were not equivalent and differed in their sign and magnitude of lags with photosynthesis phenology dates. NDVI-derived phenology was characterized by shorter growing seasons, while EVI prolonged it by about two weeks compared to the photosynthesis phenology season length. PI start and end of season dates more closely matched the start(r2 = 0.84, RMSE = 7.61) and end (r2 = 0.61, RMSE = 8.57) of photosynthesis phenology as estimated by GPP time series. PI was also found agreeing best with LSP estimates from highly spatially resolved ground digital camera observations, available for about half of the investigated FLUXNET sites. Although there were strong relationships between remotely sensed LSP and photosynthesis phenology, the relationships were not consistent across deciduous forest ecosystems implying that the vegetative and photosynthetic timing do not always follow each other in the same direction.}, keywords = {PHENOLOGY INDEX}, doi = {10.1016/j.agrformet.2015.07.005}, author = {D{\textquoteright}Odorico, Petra and Gonsamo, Alemu and Gough, Christopher M. and Bohrer, Gil and Morison, James and Wilkinson, Matthew and Hanson, Paul J. and Gianelle, Damiano and Fuentes, Jose D. and Buchmann, Nina} } @inbook {70098, title = {Use of Catalogued Long-term Biological Collections and Samples for Determining Changes in Contaminant Exposure to Organisms}, booktitle = {Environmental Contaminants: Using natural archives to track sources and long-term trends in pollution}, series = {Developments in Paleoenvironmental Research}, volume = {18}, year = {2015}, publisher = {Springer}, organization = {Springer}, abstract = {For decades, biological materials have been collected and held in museum collections, natural history collections (NHC), herbaria and environmental specimen banks (ESB). Those biological materials and accompanying data represent a potentially important source of retrospective analyses of contaminants and other chemical tracers. In ideal situations, those can provide valuable insights into changes in contaminant accumulation and concentrations over time and space. This chapter explores the benefits of such curated and catalogued specimens for contaminant research, as well as limitations and key considerations which must be kept in mind when using such samples. Three case studies examining temporal trends in contaminants using long-term biological collections are also presented.}, keywords = {MERCURY}, isbn = {978-94-017-9540-1}, author = {Campbell, Linda M. and Drevnick, Paul E.}, editor = {Blais, Jules M. and Rosen, Michael R. and Smol, John P.} } @article {70116, title = {Can EVI-derived land-surface phenology be used as a surrogate for phenology of canopy photosynthesis?}, journal = {International Journal of Remote Sensing}, volume = {35}, year = {2014}, month = {02/2014}, pages = {1162 - 1174}, abstract = {Canopy phenology plays a prominent role in determining the timing and magnitude of carbon uptake by many ecosystems. The Moderate Resolution Imaging Spectroradiometer (MODIS) Global Land Cover Dynamics product developed from the enhanced vegetation index (EVI) provides broad spatial and temporal coverage of land-surface phenology (LSP), and may serve as a useful proxy for the phenology of canopy photosynthesis. Here, we compare the MODIS growing season start and end dates (SOS and EOS) with the seasonal phenology of canopy photosynthesis estimated using the eddy covariance approach. Using 153 site-years obtained from the Ameriflux database, we calculated the SOS and EOS of gross primary production (GPP) and canopy photosynthesis capacity (CPC) for seven different boreal and temperate vegetation types. CPC is GPP at maximum radiation, estimated by fitting half-hourly GPP and radiation to a rectangular hyperbolic function. We found large mean absolute differences of up to 53 days, depending on vegetation type, between the phenology of canopy development and photosynthesis, indicating that remotely sensed LSP is not a robust surrogate of seasonal changes in GPP, particularly for evergreen needleleaf forests. This limited correspondence of ecosystem carbon uptake with the MODIS LSP product points to the need for improved remotely sensed proxies of GPP phenology.}, keywords = {REMOTE SENSING}, doi = {10.1080/01431161.2013.875636}, author = {Shen, Miaogen and Tang, Yanhong and Desai, Ankur R. and Gough, Christopher and Chen, Jin} } @article {70102, title = {Experimental infection of a periodical cicada (Magicicada cassinii) with a parasitoid (Emblemasoma auditrix) of a proto-periodical cicada (Okanagana rimosa)}, journal = {BMC Ecology}, volume = {14}, year = {2014}, month = {12/2014}, pages = {1-6}, abstract = {Background: The proto-periodical cicada Okanagana rimosa is subject to infection by the acoustically orientating parasitoid fly Emblemasoma auditrix. Furthermore, it is also the only known host of E. auditrix. Here we test the question, whether the highly adapted parasitoid can also infect other cicadas, like the periodical cicada (Magicicada cassinii) and which steps of the parasitization process can be completed. The experiments might also reveal whether such a parasitoid could hypothetically have been involved in the evolution of periodicity. Results: The hearing threshold of E. auditrix matches with the spectrum of the calling song of M. cassinii, indicating potential host localization. Behaviourally, host localization is possible by the parasitoid as it approaches a loudspeaker broadcasting the buzz part of the calling song of M. cassinii. Magicicada cassinii is readily accepted as host and for host infection the parasitoid uses the same behavioural sequence as for its host O. rimosa. A larva is deposited into the timbal of the cicada. By contrast to O. rimosa the development of the fly larva is delayed and eventually suppressed in M. cassinii. Conclusions: The host range of E. auditrix is mainly determined by acoustic parameters. This filter is important, as other sensory cues seem not to be involved in the host selection process and larva will not develop in unsuited host. Although the recent parasitoid-host system seems to be stable in terms of coexistence of both species, an acoustically hunting parasitoid could have been a selective force during evolution of prime numbered periodicity in cicadas.}, keywords = {HOST SUITABILITY}, doi = {10.1186/s12898-014-0031-7}, author = {Lakes-Harlan, Reinhard and de Vries, Thomas} } @article {70107, title = {Useless Hearing in Male Emblemasoma auditrix (Diptera, Sarcophagidae) {\textendash} A Case of Intralocus Sexual Conflict during Evolution of a Complex Sense Organ?}, journal = {PLoS ONE}, year = {2014}, month = {1/2014}, pages = {e87211}, type = {PI}, abstract = {Sensory modalities typically are important for both sexes, although sex-specific functional adaptations may occur frequently. This is true for hearing as well. Consequently, distinct behavioural functions were identified for the different insect hearing systems. Here we describe a first case, where a trait of an evolutionary novelty and a highly specialized hearing organ is adaptive in only one sex. The main function of hearing of the parasitoid fly Emblemasoma auditrix is to locate the host, males of the cicada species Okanagana rimosa, by their calling song. This task is performed by female flies, which deposit larvae into the host. We show that male E. auditrix possess a hearing sense as well. The morphology of the tympanal organ of male E. auditrix is rather similar to the female ear, which is 8\% broader than the male ear. In both sexes the physiological hearing threshold is tuned to 5 kHz. Behavioural tests show that males are able to orient towards the host calling song, although phonotaxis often is incomplete. However, despite extensive observations in the field and substantial knowledge of the biology of E. auditrix, no potentially adaptive function of the male auditory sense has been identified. This unique hearing system might represent an intralocus sexual conflict, as the complex sense organ and the behavioural relevant neuronal network is adaptive for only one sex. The correlated evolution of the sense organ in both sexes might impose substantial constraints on the sensory properties of the ear. Similar constraints, although hidden, might also apply to other sensory systems in which behavioural functions differ between sexes.}, keywords = {SEX-SPECIFIC ADAPTATIONS}, doi = {10.1371/journal.pone.0087211.t001}, author = {Lakes-Harlan, Reinhard and de Vries, Thomas and St{\"o}lting, Heiko and Stumpner, Andreas} } @article {70136, title = {Evaluating the agreement between measurements and models of net ecosystem exchange at different times and timescales using wavelet coherence: an example using data from the North American Carbon Program Site-Level Interim Synthesis}, journal = {Biogeosciences}, volume = {10}, year = {2013}, note = {Dept. of Energy, NSF}, month = {2013}, pages = {6893 - 6909}, abstract = {Earth system processes exhibit complex patterns across time, as do the models that seek to replicate these processes. Model output may or may not be significantly related to observations at different times and on different frequencies. Conventional model diagnostics provide an aggregate view of model{\textendash}data agreement, but usually do not identify the time and frequency patterns of model{\textendash}data disagreement, leaving unclear the steps required to improve model response to environmental drivers that vary on characteristic frequencies. Wavelet coherence can quantify the times and timescales at which two time series, for example time series of models and measurements, are significantly different. We applied wavelet coherence to interpret the predictions of 20 ecosystem models from the North American Carbon Program (NACP) Site-Level Interim Synthesis when confronted with eddy-covariance-measured net ecosystem exchange (NEE) from 10 ecosystems with multiple years of available data. Models were grouped into classes with similar approaches for incorporating phenology, the calculation of NEE, the inclusion of foliar nitrogen (N), and the use of model{\textendash}data fusion. Models with prescribed, rather than prognostic, phenology often fit NEE observations better on annual to interannual timescales in grassland, wetland and agricultural ecosystems. Models that calculated NEE as net primary productivity (NPP) minus heterotrophic respiration (HR) rather than gross ecosystem productivity (GPP) minus ecosystem respiration (ER) fit better on annual timescales in grassland and wetland ecosystems, but models that calculated NEE as GPP minus ER were superior on monthly to seasonal timescales in two coniferous forests. Models that incorporated foliar nitrogen (N) data were successful at capturing NEE variability on interannual (multiple year) timescales at Howland Forest, Maine. The model that employed a model{\textendash}data fusion approach often, but not always, resulted in improved fit to data, suggesting that improving model parameterization is important but not the only step for improving model performance. Combined with previous findings, our results suggest that the mechanisms driving daily and annual NEE variability tend to be correctly simulated, but the magnitude of these fluxes is often erroneous, suggesting that model parameterization must be improved. Few NACP models correctly predicted fluxes on seasonal and interannual timescales where spectral energy in NEE observations tends to be low, but where phenological events, multi-year oscillations in climatological drivers, and ecosystem succession are known to be important for determining ecosystem function. Mechanistic improvements to models must be made to replicate observed NEE variability on seasonal and interannual timescales.}, keywords = {WAVELET COHERENCE}, doi = {10.5194/bg-10-6893-2013}, author = {Stoy, P. C. and Dietze, M. C. and Richardson, A. D. and Vargas, R. and Barr, A. G. and Anderson, R. S. and Arain, M. A. and Baker, I. T. and Black, T. A. and Chen, J. M. and Cook, R. B. and Gough, C. M. and Grant, R. F. and Hollinger, D. Y. and Izaurralde, R. C. and Kucharik, C. J. and Lafleur, P. and Law, B. E. and Liu, S. and Lokupitiya, E. and Luo, Y. and Munger, J. W. and Peng, C. and Poulter, B. and Price, D. T. and Ricciuto, D. M. and Riley, W. J. and Sahoo, A. K. and Schaefer, K. and Schwalm, C. R. and Tian, H. and Verbeeck, H. and Weng, E.} } @article {70147, title = {Interannual variability of net ecosystem productivity in forests is explained by carbon flux phenology in autumn}, journal = {Global Ecology and Biogeography}, volume = {22}, year = {2013}, month = {08/2013}, pages = {994 - 1006}, abstract = {Aim To investigate the importance of autumn phenology in controlling interannual variability of forest net ecosystem productivity (NEP) and to derive new phenological metrics to explain the interannual variability of NEP. Location North America and Europe. Method Flux data from nine deciduous broadleaf forests (DBF) and 13 evergreen needleleaf forests (ENF) across North America and Europe (212 site-years) were used to explore the relationships between the yearly anomalies of annual NEP and several carbon flux based phenological indicators, including the onset/end of the growing season, onset/end of the carbon uptake period, the spring lag (time interval between the onset of growing season and carbon uptake period) and the autumn lag (time interval between the end of the carbon uptake period and the growing season). Meteorological variables, including global shortwave radiation, air temperature, soil temperature, soil water content and precipitation, were also used to explain the phenological variations. Results We found that interannual variability of NEP can be largely explained by autumn phenology, i.e. the autumn lag. While variation in neither annual gross primary productivity (GPP) nor in annual ecosystem respiration (Re) alone could explain this variability, the negative relationship between annual NEP and autumn lag was due to a larger Re/GPP ratio in years with a prolonged autumn lag. For DBF sites, a longer autumn lag coincided with a significant decrease in annual GPP but showed no correlation with annual Re. However, annual GPP was insensitive to a longer autumn lag in ENF sites but annual Re increased significantly. Main conclusions These results demonstrate that autumn phenology plays a more direct role than spring phenology in regulating interannual variability of annual NEP. In particular, the importance of respiration may be potentially underestimated in deriving phenological indicators.}, keywords = {PHENOLOGY}, doi = {10.1111/geb.12044}, author = {Wu, Chaoyang and Chen, Jing M. and Black, Andrew T and Price, David T. and Kurz, Werner A. and Desai, Ankur R. and Gonsamo, Alemu and Jassal, Rachhpal S. and Gough, Christopher M. and Bohrer, Gil and Dragoni, Danilo and Herbst, Mathias and Gielen, Bert and Berninger, Frank and Vesala, Timo and Mammarella, Ivan and Pilegaard, Kim and Blanken, Peter D.} } @article {70141, title = {Multivariate Conditional Granger Causality Analysis for Lagged Response of Soil Respiration in a Temperate Forest}, journal = {Entropy}, volume = {15}, year = {2013}, month = {10/2013}, pages = {4266 - 4284}, abstract = {Ecological multivariate systems offer a suitable data set on which to apply recent advances in information theory and causality detection. These systems are driven by the interplay of various environmental factors: meteorological and hydrological forcing, which are often correlated with each other at different time lags; and biological factors, primary producers and decomposers with both autonomous and coupled dynamics. Here, using conditional spectral Granger causality, we quantify directional causalities in a complex atmosphere-plant-soil system involving the carbon cycle. Granger causality is a statistical approach, originating in econometrics, used to identify the presence of linear causal interactions between time series of data, based on prediction theory. We first test to see if there was a significant difference in the causal structure among two treatments where carbon allocation to roots was interrupted by girdling. We then expanded the analysis, introducing radiation and soil moisture. The results showed a complex pattern of multilevel interactions, with some of these interactions depending upon the number of variables in the system. However, no significant differences emerged in the causal structure of above and below ground carbon cycle among the two treatments.}, keywords = {MULTIVARIATE GRANGER CAUSALITY}, doi = {10.3390/e15104266}, author = {Detto, Matteo and Bohrer, Gil and Nietz, Jenifer and Maurer, Kyle and Vogel, Chris and Gough, Chris and Curtis, Peter} } @article {70154, title = {Nitrogen Uptake by Trees and Mycorrhizal Fungi in a Successional Northern Temperate Forest: Insights from Multiple Isotopic Methods}, journal = {Ecosystems}, volume = {16}, year = {2013}, note = {Department of Energy}, month = {01/2013}, pages = {590-603}, type = {PI}, abstract = {Forest succession may cause changes in nitrogen (N) availability, vegetation and fungal community composition that affect N uptake by trees and their mycorrhizal symbionts. Understanding how these changes affect the functioning of the mycorrhizal symbiosis is of interest to ecosystem ecology because of the fundamental roles mycorrhizae play in providing nutrition to trees and structuring forest ecosystems. We investigated changes in tree and mycorrhizal fungal community composition, the availability and uptake of N by trees and mycorrhizal fungi in a forest undergoing a successional transition (age-related loss of early successional tree taxa). In this system, 82{\textendash}96\% of mycorrhizal hyphae were ectomycorrhizal (EM). As biomass production of arbuscular mycorrhizal (AM) trees increased, AM hyphae comprised a significantly greater proportion of total fungal hyphae, and the EM contribution to the N requirement of EM-associated tree taxa declined from greater than 75\% to less than 60\%. Increasing N availability was associated with lower EM hyphal foraging and 15N tracer uptake, yet the EM-associated later-successional species Quercus rubra was nonetheless a stronger competitor for 15N than AM-associated Acer rubrum, likely due to the more extensive nature of the persistent EM hyphal network. These results indicate that successional increases in N availability and co-dominance by AM-associated trees have increased the importance of AM fungi in the mycorrhizal community, while down-regulating EM N acquisition and transfer processes. This work advances understanding of linkages between tree and fungal community composition, and indicates that successional changes in N availability may affect competition between tree taxa with divergent resource acquisition strategies.}, keywords = {TREE}, doi = {10.1007/s10021-012-9632-1}, url = {http://link.springer.com/article/10.1007/s10021-012-9632-1}, author = {Nave, Lucas E. and Nadelhoffer, Knute J. and Moine, James M. and Diepen, Linda T. A. and Cooch, Jules K. and Van Dyke, Nicholas J.} } @article {70133, title = {Using FLUXNET data to improve models of springtime vegetation activity onset in forest ecosystems}, journal = {Agricultural and Forest Meteorology}, volume = {171-172}, year = {2013}, month = {4/2013}, pages = {46 - 56}, abstract = {Vegetation phenology is sensitive to climate change and variability, and is a first order control on the carbon budget of forest ecosystems. Robust representation of phenology is therefore needed to support model-based projections of how climate change will affect ecosystem function. A variety of models have been developed to predict species or site-specific phenology of trees. However, extension of these models to other sites or species has proven difficult. Using meteorological and eddy covariance data for 29 forest sites (encompassing 173 site-years), we evaluated the accuracy with which 11 different models were able to simulate, as a function of air temperature and photoperiod, spatial and temporal variability in the onset of spring photosynthetic activity. In parallel, we also evaluated the accuracy with which dynamics in remotely sensed vegetation indices from MODIS captured the timing of spring onset. To do this, we used a subset of sites in the FLUXNET La Thuile database located in evergreen needleleaf and deciduous broadleaf forests with distinct active and dormant seasons and where temperature is the primary driver of seasonality. As part of this analysis we evaluated predictions from refined versions of the 11 original models that include parameterizations for geographic variation in both thermal and photoperiod constraints on phenology. Results from cross-validation analysis show that the refined models predict the onset of spring photosynthetic activity with significantly higher accuracy than the original models. Estimates for the timing of spring onset from MODIS were highly correlated with the onset of photosynthesis derived from flux measurements, but were biased late for needleleaf sites. Our results demonstrate that simple phenology models can be used to predict the timing of spring photosynthetic onset both across sites and across years at individual sites. By extension, these models provide an improved basis for predicting how the phenology and carbon budgets of temperature-limited forest ecosystems may change in the coming decades.}, keywords = {SEASONALITY MODELING}, doi = {10.1016/j.agrformet.2012.11.018}, author = {Melaas, Eli K. and Richardson, Andrew D. and Friedl, Mark A. and Dragoni, Danilo and Gough, Christopher M. and Herbst, Mathias and Montagnani, Leonardo and Moors, Eddy} } @article {70178, title = {The Botanical Teaching Legacy of Edward G. Voss at the University of Michigan Biological Station}, journal = {The Michigan Botanist}, volume = {51}, year = {2012}, note = {UMBS}, month = {01/2012}, pages = {32-41}, publisher = {MPublishing}, abstract = {The end of May marked Ed Voss{\textquoteright} annual trip to northern Michigan{\textemdash}his botanical getaway since well before he became Professor of Biology and Curator at the University of Michigan, Ann Arbor. This locale fortuitously provided his inspiration for decades of pioneering research on the Michigan flora. His grandfather had acquired their cabin on the Straits of Mackinac in 1930 to avoid hay fever in their hometown of Dayton, Ohio. In September of that year, at the age of one, Ed spent his first night along the Straits (Voss 2008). It was here in northern Michigan that Ed established a lasting legacy from the many lives he touched in the classroom, and field, at the University of Michigan Biological Station (UMBS)}, keywords = {TEACHING}, url = {http://hdl.handle.net/2027/spo.0497763.0051.105}, author = {Davis, Charles C. and Gunn, Melanie and Hellquist, C. Eric} } @article {70161, title = {Contributions of individual reactive biogenic volatile organic compounds to organic nitrates above a mixed forest}, journal = {Atmospheric Chemistry and Physics}, volume = {12}, year = {2012}, month = {2012}, pages = {10125 - 10143}, abstract = {. Biogenic volatile organic compounds (BVOCs) can react in the atmosphere to form organic nitrates, which serve as NOx (NO + NO2) reservoirs, impacting ozone and secondary organic aerosol production, the oxidative capacity of the atmosphere, and nitrogen availability to ecosystems. To examine the contributions of biogenic emissions and the formation and fate of organic nitrates in a forest environment, we simulated the oxidation of 57 individual BVOCs emitted from a rural mixed forest in northern Michigan. Key BVOCoxidant reactions were identified for future laboratory and field investigations into reaction rate constants, yields, and speciation of oxidation products. Of the total simulated organic nitrates, monoterpenes contributed \~{} 70 \% in the early morning at \~{} 12 m above the forest canopy when isoprene emissions were low. In the afternoon, when vertical mixing and isoprene nitrate production were highest, the simulated contribution of isoprene-derived organic nitrates was greater than 90 \% at all altitudes, with the concentration of secondary isoprene nitrates increasing with altitude. Notably, reaction of isoprene with NO3 leading to isoprene nitrate formation was found to be significant (\~{} 8 \% of primary organic nitrate production) during the daytime, and monoterpene reactions with NO3 were simulated to comprise up to \~{} 83 \% of primary organic nitrate production at night. Lastly, forest succession, wherein aspen trees are being replaced by pine and maple trees, was predicted to lead to increased afternoon concentrations of monoterpene-derived organic nitrates. This further underscores the need to understand the formation and fate of these species, which have different chemical pathways and oxidation products compared to isoprene-derived organic nitrates and can lead to secondary organic aerosol formation.}, keywords = {TERPENES}, doi = {10.5194/acp-12-10125-2012}, author = {Pratt, K. A. and Mielke, L. H. and Shepson, P. B. and Bryan, A. M. and Steiner, A. L. and Ortega, J. and Daly, R. and Helmig, D. and Vogel, C. S. and Griffith, S. and Dusanter, S. and Stevens, P. S. and Alaghmand, M.} } @article {70163, title = {Evaluation of leaf-to-canopy upscaling methodologies against carbon flux data in North America}, journal = {Journal of Geophysical Research}, volume = {117}, year = {2012}, month = {2012}, pages = {17}, abstract = {Despite the wide acceptance of the {\textquotedblleft}big-leaf{\textquotedblright} upscaling strategy in evapotranspiration modeling (e.g., the Penman-Monteith model), its usefulness in simulating canopy photosynthesis may be limited by the underlying assumption of homogeneous response of carbon assimilation light-response kinetics through the canopy. While previous studies have shown that the separation of the canopy into sunlit and shaded parts (i.e., two-leaf model) is typically more effective than big-leaf models for upscaling photosynthesis from leaf to canopy, a systematic comparison between these two upscaling strategies among multiple ecosystems has not been presented. In this study, gross primary productivity was modeled using two-leaf and big-leaf upscaling approaches in the Boreal Ecosystem Productivity Simulator for shrublands, broadleaf, and conifer forest types. When given the same leaf-level photosynthetic parameters, the big-leaf approach significantly underestimated canopy-level GPP while the two-leaf approach more closely predicted both the magnitude and day-to-day variability in eddy covariance measurements. The underestimation by the big-leaf approach is mostly caused by its exclusion of the photosynthetic contributions of shaded leaves. Tests of the model sensitivity to a foliage clumping index revealed that the contribution of shaded leaves to the total simulated productivity can be as high as 70\% for highly clumped stands and seldom decreases below \~{}40\% for less-clumped canopies. Our results indicate that accurate upscaling of photosynthesis across a broad array of ecosystems requires an accurate description of canopy structure in ecosystem models.}, keywords = {PRIMARY PRODUCTION}, doi = {10.1029/2010JG001407}, author = {Sprintsin, Michael and Chen, Jing M. and Desai, Ankur R. and Gough, Christopher M.} } @article {70172, title = {Evidence of Long-distance Dispersal and Successful Interpopulation Breeding of the Endangered Piping Plover}, journal = {Waterbirds}, volume = {35}, year = {2012}, month = {07/2012}, pages = {642-644}, abstract = {There are two recognized subspecies of the Piping Plover (Charadrius melodus): the Atlantic coast United States and Canada ({\textquoteleft}Atlantic{\textquoteright}) subspecies and the Great Lakes and Northern Great Plains ({\textquoteleft}Interior{\textquoteright}) subspecies. More than 7,000 Piping Plovers have been banded and monitored since 1982, yet no individual marked as a hatchling or breeding adult in the range of one subspecies has been reported breeding in the range of the other. Recent molecular genetic analyses further support subspecific taxonomic classification of Atlantic and Interior breeding populations. On 22 May 2011, a banded Piping Plover and unbanded mate were observed nesting on North Core Banks, Cape Lookout National Seashore, North Carolina, USA. The uniquely-banded adult was a female captured as a chick at Wasaga Beach, Georgian Bay, Ontario, Canada; the female nested unsuccessfully in its first breeding year at Tawas Point State Park, Michigan, USA and then successfully fledged two chicks in its second breeding year at North Core Banks, North Carolina, USA. The observation is the first confirmed record of a Piping Plover dispersing from its subspecies{\textquoteright} range and successfully breeding in the range of the other subspecies.}, keywords = {SUBSPECIES}, doi = {10.1675/063.035.0414}, author = {Hillman, M.D. and Karpanty, S.M. and Fraser, J. D. and Cuthbert, Francesca Jean and Altman, Jonathan M. and Borneman, Tracy E. and Derose-Wilson, Audrey} } @article {70164, title = {In-canopy gas-phase chemistry during CABINEX 2009: sensitivity of a 1-D canopy model to vertical mixing and isoprene chemistry}, journal = {Atmospheric Chemistry and Physics}, volume = {12}, year = {2012}, note = {PROPHET}, month = {2012}, pages = {8829 - 8849}, publisher = {EGU Journals}, type = {CABINEX}, abstract = {Vegetation emits large quantities of biogenic volatile organic compounds (BVOC). At remote sites, these compounds are the dominant precursors to ozone and secondary organic aerosol (SOA) production, yet current field studies show that atmospheric models have difficulty in capturing the observed HOx cycle and concentrations of BVOC oxidation products. In this manuscript, we simulate BVOC chemistry within a forest canopy using a one-dimensional canopy-chemistry model (Canopy Atmospheric CHemistry Emission model; CACHE) for a mixed deciduous forest in northern Michigan during the CABINEX 2009 campaign. We find that the base-case model, using fully-parameterized mixing and the simplified biogenic chemistry of the Regional Atmospheric Chemistry Model (RACM), underestimates daytime in-canopy vertical mixing by 50{\textendash}70\% and by an order of magnitude at night, leading to discrepancies in the diurnal evolution of HOx, BVOC, and BVOC oxidation products. Implementing observed micrometeorological data from above and within the canopy substantially improves the diurnal cycle of modeled BVOC, particularly at the end of the day, and also improves the observation-model agreement for some BVOC oxidation products and OH reactivity. We compare the RACM mechanism to a version that includes the Mainz isoprene mechanism (RACM-MIM) to test the model sensitivity to enhanced isoprene degradation. RACM-MIM simulates higher concentrations of both primary BVOC (isoprene and monoterpenes) and oxidation products (HCHO, MACR+MVK) compared with RACM simulations. Additionally, the revised mechanism alters the OH concentrations and increases HO2. These changes generally improve agreement with HOx observations yet overestimate BVOC oxidation products, indicating that this isoprene mechanism does not improve the representation of local chemistry at the site. Overall, the revised mechanism yields smaller changes in BVOC and BVOC oxidation product concentrations and gradients than improving the parameterization of vertical mixing with observations, suggesting that uncertainties in vertical mixing parameterizations are an important component in understanding observed BVOC chemistry.}, keywords = {VEGETATION}, doi = {10.5194/acp-12-8829-2012}, author = {Bryan, A. M. and Bertman, S. B. and Carroll, M. A. and Dusanter, S. and Edwards, G. D. and Forkel, R. and Griffith, S. and Guenther, A. B. and Hansen, R. F. and Helmig, D. and Jobson, B. T. and Keutsch, F. N. and Lefer, B. L. and Pressley, S. N. and Shepson, P. B. and Stevens, P. S. and Steiner, A. L.} } @article {70176, title = {Observations and modeling of formaldehyde at the PROPHET mixed hardwood forest site in 2008}, journal = {Atmospheric Environment}, volume = {49}, year = {2012}, month = {03/2012}, pages = {403-410}, abstract = {We report the first field measurements of gas-phase formaldehyde (HCHO) via laser-induced fluorescence (LIF) obtained August 1{\textendash}8, 2008 at the PROPHET mixed hardwood forest site at the University of Michigan Biological Station. HCHO mixing ratios above the canopy ranged from a nighttime minimum of \~{}0.5 ppbv to afternoon maxima of \~{}4.2 ppbv. Daytime HCHO mixing ratios were compared to two zero-dimensional box models: one based on the Master Chemical Mechanism v3.2 (MCM), the other using a simplified treatment of HCHO production. Both models over-predicted HCHO relative to observations. Sensitivity analyses demonstrated that increasing vertical dilution and/or decreasing OH concentrations would result in a significant reduction in this over-prediction for both models, as did reducing NO concentrations in the MCM based model. On average, the two models agreed to within 9\%, though sensitivity analyses of changing NO and HO2 concentrations result in significant deviation. This displays that modeled HCHO production is heavily-dependent on the yields and rates of RO2 destruction pathways under low NO conditions, which may have implications for simplified mechanisms and global predictions of isoprene emission based on satellite HCHO measurements.}, keywords = {MODELS}, doi = {10.1016/j.atmosenv.2011.09.053}, author = {Galloway, Melissa M. and DiGangi, Joshua P. and Hottle, John Robert and Huisman, Andrew J. and Levi H. Mielke and Alaghmand, Marjan and Shepson, Paul B. and Weremijewicz, Joanna and Klavon, Hugh and McNeal, Fredrick M. and Carroll, Mary Anne and Griffith, Stephen and Hansen, Robert F. and Dusanter, Sebastien and Stevens, Philip S. and Bertman, Steven B. and Keutsch, Frank N.} } @article {70177, title = {Terrestrial biosphere models need better representation of vegetation phenology: results from the North American Carbon Program Site Synthesis}, journal = {Global Change Biology}, volume = {18}, year = {2012}, month = {02/2012}, pages = {566 - 584}, type = {PI}, abstract = {Phenology, by controlling the seasonal activity of vegetation on the land surface, plays a fundamental role in regulating photosynthesis and other ecosystem processes, as well as competitive interactions and feedbacks to the climate system. We conducted an analysis to evaluate the representation of phenology, and the associated seasonality of ecosystem-scale CO2 exchange, in 14 models participating in the North American Carbon Program Site Synthesis. Model predictions were evaluated using long-term measurements (emphasizing the period 2000{\textendash}2006) from 10 forested sites within the AmeriFlux and Fluxnet-Canada networks. In deciduous forests, almost all models consistently predicted that the growing season started earlier, and ended later, than was actually observed; biases of 2 weeks or more were typical. For these sites, most models were also unable to explain more than a small fraction of the observed interannual variability in phenological transition dates. Finally, for deciduous forests, misrepresentation of the seasonal cycle resulted in over-prediction of gross ecosystem photosynthesis by +160 {\textpm} 145 g C m2 yr1 during the spring transition period and +75 {\textpm} 130 g C m2 yr1 during the autumn transition period (13\% and 8\% annual productivity, respectively) compensating for the tendency of most models to under-predict the magnitude of peak summertime photosynthetic rates. Models did a better job of predicting the seasonality of CO2 exchange for evergreen forests. These results highlight the need for improved understanding of the environmental controls on vegetation phenology and incorporation of this knowledge into better phenological models. Existing models are unlikely to predict future responses of phenology to climate change accurately and therefore will misrepresent the seasonality and interannual variability of key biosphere{\textendash}atmosphere feedbacks and interactions in coupled global climate models.}, keywords = {spring onset}, doi = {10.1111/j.1365-2486.2011.02562.x}, author = {Richardson, Andrew D. and Anderson, Ryan S. and Arain, M Altaf and Barr, Alan G. and Bohrer, Gil and Chen, Guangsheng and Chen, Jing M. and Ciais, Philippe and Davis, Kenneth J. and Desai, Ankur R. and Dietze, Michael C. and Dragoni, Danilo and Garrity, Steven R. and Gough, Christopher M. and Grant, Robert and Hollinger, David Y. and Margolis, Hank A and McCaughey, Harry and Migliavacca, Mirco and Monson, Russell K and Munger, J. William and Poulter, Benjamin and Raczka, Brett M. and Ricciuto, Daniel M. and Sahoo, Alok K. and Schaefer, Kevin and Tian, Hanqin and Vargas, Rodrigo and Verbeeck, Hans and Xiao, Jingfeng and Xue, Yongkang} } @article {70209, title = {Comparative phylogeography of red maple (Acer rubrum L.) and silver maple (Acer saccharinum L.): impacts of habitat specialization, hybridization and glacial history}, journal = {Journal of Biogeography}, volume = {38}, year = {2011}, month = {05/2011}, pages = {992 - 1005}, abstract = {Aim We analysed variation in chloroplast DNA (cpDNA) in red maple (Acer rubrum L.) and silver maple (Acer saccharinum L.) across a large part of their geographic ranges. Acer rubrum is one of the most common and morphologically variable deciduous trees of eastern North America, while its sister species A. saccharinum has a more restricted habitat distribution and displays markedly less morphological variation. Our objective was to infer the impact of biogeographic history on cpDNA diversity and phylogeographic structure in both species. Location Deciduous forests of eastern North America. Methods We sequenced 1289 to 1645 bp of non-coding cpDNA from A. rubrum (n = 258) and A. saccharinum (n = 83). Maximum parsimony networks and spatial analysis of molecular variance (SAMOVA) were used to analyse phylogeographic structure. Rarefaction analyses were used to compare genetic diversity. Results A total of 40 cpDNA haplotypes were recovered from A. rubrum (38 haplotypes) and A. saccharinum (7 haplotypes). Five of the seven A. saccharinum haplotypes were shared with nearby samples of A. rubrum. SAMOVA recovered four phylogeographic groups for A. rubrum in: (1) south-eastern USA, (2) the Gulf and south-eastern Coastal Plain, (3) the lower Mississippi River Valley, and (4) the central and northern regions of eastern North America. Acer saccharinum had significantly lower haplotype diversity than A. rubrum, and novel haplotypes in post-glaciated northern limits of its range were shared with A. rubrum. Main conclusions This is the first study of A. rubrum to report a distinct phylogeographic group centred on the lower Mississippi River, and the first to examine data comparatively with A. saccharinum. We hypothesized that A. rubrum would display stronger phylogeographic structure and greater haplotype diversity than A. saccharinum because of its greater geographic range, and ecological and morphological variation. This hypothesis was supported by the cpDNA analysis. The sharing of cpDNA and chloroplast simple sequence repeat (cpSSR) haplotypes in areas of geographic overlap provides evidence of introgression, which led to an increase in haplotype diversity in both species, and to novel phylogeographic structure in A. rubrum. We recommend that introgression be considered, along with other potential causes, as an explanation for the phylogeographic structure of cpDNA in plants.}, keywords = {MAPLE}, doi = {10.1111/j.1365-2699.2010.02462.x}, author = {Saeki, Ikuyo and Dick, C. W. and Barnes, Burton Verne and Murakami, Noriaki} } @article {70182, title = {Forest Canopy Properties and Variation in Aboveground Net Primary Production over Upper Great Lakes Landscapes}, journal = {Ecosystems}, volume = {14}, year = {2011}, month = {9/2011}, pages = {865 - 879}, abstract = {Relationships among aboveground net primary production (ANPP) and forest canopy properties were investigated in secondary successional forests of similar age and disturbance history in northern Lower Michigan, USA. Aboveground biomass, ANPP, canopy leaf area index (LAI), and several canopy nitrogen (N) measures were estimated from 12 stands representing major landform-level ecosystems and vegetation associations. Stand single-date and growing season average normalized difference vegetation indices (NDVI) were derived from Landsat TM. ANPP correlated most strongly with total canopy N content (r 2 = 0.81, P < 0.001), followed by LAI (r 2 = 0.73, P < 0.001) and area-based canopy-average leaf N concentration (r 2 = 0.37, P < 0.05). No significant relationship was detected between ANPP and mass-based canopy-average leaf N concentration. Stand ANPP correlated positively with both total canopy N content (r 2 = 0.62, P < 0.05) and mass-based leaf N concentration (r 2 = 0.53, P < 0.05) of commonly dominant Populus spp. Relatively higher ANPP, total canopy N content and LAI corresponded to simultaneous presence of shade-intolerant P. grandidentata with shade-tolerant species. Both forms of NDVI were significantly related to ANPP, and more strongly to total canopy N content and LAI; relationships were stronger for seasonally averaged (r 2 >= 0.75, P < 0.001) than for single-date NDVI (r 2 >= 0.52, P < 0.01). Results indicate that on the transitioning study landscapes, ANPP was more closely related to canopy N content than to LAI, seasonally averaged NDVI was a more reliable predictor of ANPP and canopy properties than the single-date index, whereas measured canopy characteristics varied significantly between major landform-level ecosystems. The ongoing decline of P. grandidentata is likely to alter aboveground carbon and pools and fluxes in the course of succession.}, keywords = {POPULUS}, doi = {10.1007/s10021-011-9451-9}, author = {Dronova, Iryna and Bergen, Kathleen M. and Ellsworth, David S.} } @article {70186, title = {Nitric acid photolysis on forest canopy surface as a source for tropospheric nitrous acid}, journal = {Nature Geoscience}, volume = {4}, year = {2011}, month = {5/2011}, pages = {440 - 443}, abstract = {Photolysis of nitrous acid generates hydroxyl radicals{\textemdash}a key atmospheric oxidant{\textemdash}in the lower atmosphere. Significant concentrations of nitrous acid have been reported in the rural atmospheric boundary layer during the day, where photolysis of nitrous acid accounts for up to 42\% of sunlight-induced radical production. The observed concentrations of nitrous acid are thought to be sustained by heterogeneous reactions involving precursors such as nitrogen oxides and nitric acid. Here, we present direct measurements of nitrous acid flux over a rural forest canopy in Michigan, together with surface nitrate loading at the top of the canopy. We report a significant upward flux of nitrous acid during the day, with a peak around noontime. Daytime nitrous acid flux was positively correlated with the product of leaf surface nitrate loading and the rate constant of nitrate photolysis. We suggest that the photolysis of nitric acid on forest canopies is a significant daytime source of nitrous acid to the lower atmosphere in rural environments, and could serve as an important pathway for the remobilization of deposited nitric acid.}, keywords = {PHOTOLYSIS}, doi = {10.1038/ngeo1164}, author = {Zhou, Xianliang and Zhang, Ning and TerAvest, Michaela and Tang, David and Hou, Jian and Bertman, Steven B. and Alaghmand, Marjan and Shepson, Paul B. and Carroll, Mary Anne and Griffith, Stephen and Dusanter, Sebastien and Stevens, Philip S.} } @article {70211, title = {Terrestrial biosphere models need better representation of vegetation phenology: results from the North American Carbon Program Site Synthesis}, journal = {Global Change Biology}, volume = {18}, year = {2011}, month = {02/2012}, pages = {566 - 584}, abstract = {Phenology, by controlling the seasonal activity of vegetation on the land surface, plays a fundamental role in regulating photosynthesis and other ecosystem processes, as well as competitive interactions and feedbacks to the climate system. We conducted an analysis to evaluate the representation of phenology, and the associated seasonality of ecosystem-scale CO2 exchange, in 14 models participating in the North American Carbon Program Site Synthesis. Model predictions were evaluated using long-term measurements (emphasizing the period 2000{\textendash}2006) from 10 forested sites within the AmeriFlux and Fluxnet-Canada networks. In deciduous forests, almost all models consistently predicted that the growing season started earlier, and ended later, than was actually observed; biases of 2 weeks or more were typical. For these sites, most models were also unable to explain more than a small fraction of the observed interannual variability in phenological transition dates. Finally, for deciduous forests, misrepresentation of the seasonal cycle resulted in over-prediction of gross ecosystem photosynthesis by +160 {\textpm} 145 g C m-2 yr-1 during the spring transition period and +75 {\textpm} 130 g C m-2 yr-1 during the autumn transition period (13\% and 8\% annual productivity, respectively) compensating for the tendency of most models to under-predict the magnitude of peak summertime photosynthetic rates. Models did a better job of predicting the seasonality of CO2 exchange for evergreen forests. These results highlight the need for improved understanding of the environmental controls on vegetation phenology and incorporation of this knowledge into better phenological models. Existing models are unlikely to predict future responses of phenology to climate change accurately and therefore will misrepresent the seasonality and interannual variability of key biosphere{\textendash}atmosphere feedbacks and interactions in coupled global climate models.}, keywords = {SENESCENCE}, doi = {10.1111/j.1365-2486.2011.02562.x}, author = {Richardson, Andrew D. and Anderson, Ryan S. and Arain, M Altaf and Barr, Alan G. and Bohrer, Gil and Chen, Guangsheng and Chen, Jing M. and Ciais, Philippe and Davis, Kenneth J. and Desai, Ankur R. and Dietze, Michael C. and Dragoni, Danilo and Garrity, Steven R. and Gough, Christopher M. and Grant, Robert and Hollinger, David Y. and Margolis, Hank A and McCaughey, Harry and Migliavacca, Mirco and Monson, Russell K and Munger, J. William and Poulter, Benjamin and Raczka, Brett M. and Ricciuto, Daniel M. and Sahoo, Alok K. and Schaefer, Kevin and Tian, Hanqin and Vargas, Rodrigo and Verbeeck, Hans and Xiao, Jingfeng and Xue, Yongkang} } @article {70192, title = {Thermal adaptation of net ecosystem exchange}, journal = {Biogeosciences}, volume = {8}, year = {2011}, month = {2011}, pages = {1453 - 1463}, abstract = {Thermal adaptation of gross primary production and ecosystem respiration has been well documented over broad thermal gradients. However, no study has examined their interaction as a function of temperature, i.e. the thermal responses of net ecosystem exchange of carbon (NEE). In this study, we constructed temperature response curves of NEE against temperature using 380 site-years of eddy covariance data at 72 forest, grassland and shrubland ecosystems located at latitudes ranging from ~29{\textdegree} N to 64{\textdegree} N. The response curves were used to define two critical temperatures: transition temperature (Tb) at which ecosystem transferring from carbon source to sink and optimal temperature (To) at which carbon uptake is maximized. Tb was strongly correlated with annual mean air temperature. To was strongly correlated with mean temperature during the net carbon uptake period across the study ecosystems. Our results suggested that ecosystem CO2 flux switched from source to sink when air temperature reached annual mean temperature in spring and reached maximum uptake at mean temperature of the net carbon uptake period. Our results imply that the net ecosystem exchange of carbon adapt to the temperature across the geographical range due to intrinsic connections between vegetation primary production and ecosystem respiration.}, keywords = {THERMAL}, doi = {10.5194/bg-8-1453-2011}, author = {Yuan, W. and Luo, Y. and Liang, S. and Yu, G. and Niu, S. and Stoy, P. and Chen, J. and Desai, A. R. and Lindroth, A. and Gough, Christopher M. and Ceulemans, R. and Arain, A. and Bernhofer, C. and Cook, B. and Cook, D. R. and Dragoni, Danilo and Gielen, B. and Janssens, I. A. and Longdoz, B. and Liu, H. and Lund, M. and Matteucci, G. and Moors, E. and Scott, R. L. and Seufert, G. and Varner, R.} } @article {70254, title = {Albedo estimates for land surface models and support for a new paradigm based on foliage nitrogen concentration}, journal = {Global Change Biology}, volume = {16}, year = {2010}, month = {02/2010}, pages = {696 - 710}, abstract = {Vegetation albedo is a critical component of the Earth{\textquoteright}s climate system, yet efforts to evaluate and improve albedo parameterizations in climate models have lagged relative to other aspects of model development. Here, we calculated growing season albedos for deciduous and evergreen forests, crops, and grasslands based on over 40 site-years of data from the AmeriFlux network and compared them with estimates presently used in the land surface formulations of a variety of climate models. Generally, the albedo estimates used in land surface models agreed well with this data compilation. However, a variety of models using fixed seasonal estimates of albedo overestimated the growing season albedo of northerly evergreen trees. In contrast, climate models that rely on a common two-stream albedo submodel provided accurate predictions of boreal needle-leaf evergreen albedo but overestimated grassland albedos. Inverse analysis showed that parameters of the two-stream model were highly correlated. Consistent with recent observations based on remotely sensed albedo, the AmeriFlux dataset demonstrated a tight linear relationship between canopy albedo and foliage nitrogen concentration (for forest vegetation: albedo=0.01+0.071\%N, r2=0.91; forests, grassland, and maize: albedo=0.02+0.067\%N, r2=0.80). However, this relationship saturated at the higher nitrogen concentrations displayed by soybean foliage. We developed similar relationships between a foliar parameter used in the two-stream albedo model and foliage nitrogen concentration. These nitrogen-based relationships can serve as the basis for a new approach to land surface albedo modeling that simplifies albedo estimation while providing a link to other important ecosystem processes.}, keywords = {VEGETATION}, doi = {10.1111/j.1365-2486.2009.02028.x}, author = {Hollinger, David and Ollinger, S. V. and Richardson, Andrew D. and Meyers, Tilden and Dail, D Bryan and Martin, M. E. and Scott, N. A. and Arkebauer, T. J. and Baldocchi, Dennis and Clark, K. L. and Curtis, Peter S. and Davis, Kenneth J. and Desai, Ankur R. and Dragoni, Danilo and Goulden, M. L. and Gu, Lianhong and Katul, Gabriel and Pallardy, Stephen G and Paw U, Kyaw Tha and Schmid, Hans Peter and Stoy, P. C. and Suyker, A. E. and Verma, Shashi} } @article {70245, title = {Climate control of terrestrial carbon exchange across biomes and continents}, journal = {Environmental Research Letters}, volume = {5}, year = {2010}, month = {07/2010}, pages = {034007}, abstract = {Understanding the relationships between climate and carbon exchange by terrestrial ecosystems is critical to predict future levels of atmospheric carbon dioxide because of the potential accelerating effects of positive climate{\textendash}carbon cycle feedbacks. However, directly observed relationships between climate and terrestrial CO2 exchange with the atmosphere across biomes and continents are lacking. Here we present data describing the relationships between net ecosystem exchange of carbon (NEE) and climate factors as measured using the eddy covariance method at 125 unique sites in various ecosystems over six continents with a total of 559 site-years. We find that NEE observed at eddy covariance sites is (1) a strong function of mean annual temperature at mid- and high-latitudes, (2) a strong function of dryness at mid- and low-latitudes, and (3) a function of both temperature and dryness around the mid-latitudinal belt (45{\textdegree}N). The sensitivity of NEE to mean annual temperature breaks down at ~ 16 {\textdegree}C (a threshold value of mean annual temperature), above which no further increase of CO2 uptake with temperature was observed and dryness influence overrules temperature influence.}, keywords = {SOLAR RADIATION}, doi = {10.1088/1748-9326/5/3/034007}, author = {Yi, Chuixiang and Ricciuto, Daniel and Li, Runze and Wolbeck, John and Xu, Xiyan and Nilsson, Mats and Aires, Luis and Albertson, John D and Ammann, Christof and Arain, M Altaf and de Araujo, Alessandro C and Aubinet, Marc and Aurela, Mika and Barcza, Zolt{\'a}n and Barr, Alan and Berbigier, Paul and Beringer, Jason and Bernhofer, Christian and Black, Andrew T and Bolstad, Paul V. and Bosveld, Fred C and Broadmeadow, Mark S J and Buchmann, Nina and Burns, Sean P and Cellier, Pierre and Chen, Jingming and Chen, Jiquan and Ciais, Philippe and Clement, Robert and Cook, Bruce D. and Curtis, Peter S. and Dail, D Bryan and Dellwik, Ebba and Delpierre, Nicolas and Desai, Ankur R. and Dore, Sabina and Dragoni, Danilo and Drake, Bert G and Dufr{\^e}ne, Eric and Dunn, Allison and Elbers, Jan and Eugster, Werner and Falk, Matthias and Feigenwinter, Christian and Flanagan, Lawrence B and Foken, Thomas and Frank, John and Fuhrer, Juerg and Gianelle, Damiano and Goldstein, Allen and Goulden, Mike and Granier, Andre and Gr{\"u}nwald, Thomas and Gu, Lianhong and Guo, Haiqiang and Hammerle, Albin and Han, Shijie and Hanan, Niall P and Haszpra, L{\'a}szl{\'o} and Heinesch, Bernard and Helfter, Carole and Hendriks, Dimmie and Hutley, Lindsay B and Ibrom, Andreas and Jacobs, Cor and Johansson, Torbj{\"o}rn and Jongen, Marjan and Katul, Gabriel and Kiely, Gerard and Klumpp, Katja and Knohl, Alexander and Kolb, Thomas and Kutsch, Werner L and Lafleur, Peter and Laurila, Tuomas and Leuning, Ray and Lindroth, Anders and Liu, Heping and Loubet, Benjamin and Manca, Giovanni and Marek, Michal and Margolis, Hank A and Martin, Timothy A and Massman, William J and Matamala, Roser and Matteucci, Giorgio and McCaughey, Harry and Merbold, Lutz and Meyers, Tilden and Migliavacca, Mirco and Miglietta, Franco and Misson,, Laurent and M{\"o}lder, Meelis and Moncrieff, John and Monson, Russell K and Montagnani, Leonardo and Montes-Helu, Mario and Moors, Eddy and Moureaux, Christine and Mukelabai, Mukufute M and Munger, J. William and Myklebust, May and Nagy, Zolt{\'a}n and Noormets, Asko and Oechel, Walter and Oren, Ram and Pallardy, Stephen G and Paw U, Kyaw Tha and Pereira, Jo{\~a}o S and Pilegaard, Kim and Pint{\'e}r, Krisztina and Pio, Casimiro and Pita, Gabriel and Powell, Thomas L and Rambal, Serge and Randerson, James T and von Randow, Celso and Rebmann, Corinna and Rinne, Janne and Rossi, Federica and Roulet, Nigel and Ryel, Ronald J and Sagerfors, Jorgen and Saigusa, Nobuko and Sanz, Mar{\'\i}a Jos{\'e} and Mugnozza, Giuseppe-Scarascia and Schmid, Hans Peter and Seufert, Guenther and Siqueira, Mario and Soussana, Jean-Fran{\c c}ois and Starr, Gregory and Sutton, Mark A and Tenhunen, John and Tuba,, Zolt{\'a}n and Tuovinen, Juha-Pekka and Valentini, Riccardo and Vogel, Christoph S. and Wang, Jingxin and Wang, Shaoqiang and Wang, Weiguo and Welp, Lisa R and Wen, Xuefa and Wharton, Sonia and Wilkinson, Matthew and Williams, Christopher A and Wohlfahrt, Georg and Yamamoto, Susumu and Yu, Guirui and Zampedri, Roberto and Zhao, Bin and Zhao, Xinquan} } @article {70231, title = {CO2 Fluxes at northern fens and bogs have opposite responses to inter-annual fluctuations in water table}, journal = {Geophysical Research Letters}, volume = {37}, year = {2010}, month = {2010}, pages = {1-5}, abstract = {This study compares eddy-covariance measurements of carbon dioxide fluxes at six northern temperate and boreal peatland sites in Canada and the northern United States of America, representing both bogs and fens. The two peatland types had opposite responses of gross ecosystem photosynthesis (GEP) and ecosystem respiration (ER) to inter-annual fluctuations in water table level. At fens, wetter conditions were correlated with lower GEP and ER, while at bogs wetter conditions were correlated with higher GEP and ER. We hypothesize that these contrasting responses are due to differences in the relative contributions of vascular plants and mosses. The coherence of our results between sites representing a range of average environmental conditions indicates ecosystem-scale differences in resilience to hydrological changes that should be taken into account when considering the future of peatland ecosystem services such as carbon sequestration under changing environmental conditions. Citation: Sulman, B. N., A. R. Desai, N. Z. Saliendra, P. M. Lafleur, L. B. Flanagan, O. Sonnentag, D. S. Mackay, A. G. Barr, and G. van der Kamp (2010), CO2 fluxes at northern fens and bogs have opposite responses to inter-annual fluctuations in water table, Geophys. Res. Lett., 37, L19702, doi:10.1029/2010GL044018.}, keywords = {WETLANDS}, doi = {10.1029/2010GL044018}, url = {This study compares eddy-covariance measurements of carbon dioxide fluxes at six northern temperate and boreal peatland sites in Canada and the northern United States of America, representing both bogs and fens. The two peatland types had opposite respo}, author = {Sulman, Benjamin N. and Desai, Ankur R. and Saliendra, Nicanor Z. and Lafleur, Peter M. and Flanagan, Lawrence B and Sonnentag, Oliver and Mackay, D. Scott and Barr, Alan G. and van der Kamp, Garth} } @article {70247, title = {Isolation and characterization of microsatellite loci in the common milkweed, Asclepias syriaca (Apocynaceae)}, journal = {American Journal of Botany}, volume = {97}, year = {2010}, month = {05/2010}, pages = {e37 - e38}, abstract = {{\textbullet} Premise of the study: Microsatellite primers were developed for the common milkweed, Asclepias syriaca L., to assist in genet identification and the analysis of spatial genetic structure. {\textbullet} Methods and Results: Using an enrichment cloning protocol, eight microsatellite loci were isolated and characterized in a Michigan population of A. syriaca. The primers amplified di- and trinucleotide repeats with 4{\textendash}13 alleles per locus. {\textbullet} Conclusions: The primers will be useful for studies of clonality and gene flow in natural populations.}, keywords = {VASCULAR PLANTS}, doi = {10.3732/ajb.1000064}, author = {Kabat, S. M. and Dick, C. W. and Hunter, Mark D.} } @article {70236, title = {Molecular phylogenetics of porcini mushrooms (Boletus section Boletus)}, journal = {Molecular Phylogenetics and Evolution}, volume = {57}, year = {2010}, note = {UMBS mentioned in the acknowledgements.}, month = {12/2010}, pages = {1276 - 1292}, abstract = {Porcini (Boletus section Boletus: Boletaceae: Boletineae: Boletales) are a conspicuous group of wild, edible mushrooms characterized by fleshy fruiting bodies with a poroid hymenophore that is {\textquotedblleft}stuffed{\textquotedblright} with white hyphae when young. Their reported distribution is with ectomycorrhizal plants throughout the Northern Hemisphere. Little progress has been made on the systematics of this group using modern molecular phylogenetic tools because sampling has been limited primarily to European species and the genes employed were insufficient to resolve the phylogeny. We examined the evolutionary history of porcini by using a global geographic sampling of most known species, new discoveries from little explored areas, and multiple genes. We used 78 sequences from the fast-evolving nuclear internal transcribed spacers and are able to recognize 18 reciprocally monophyletic species. To address whether or not porcini form a monophyletic group, we compiled a broadly sampled dataset of 41 taxa, including other members of the Boletineae, and used separate and combined phylogenetic analysis of sequences from the nuclear large subunit ribosomal DNA, the largest subunit of RNA polymerase II, and the mitochondrial ATPase subunit six gene. Contrary to previous studies, our separate and combined phylogenetic analyses support the monophyly of porcini. We also report the discovery of two taxa that expand the known distribution of porcini to Australia and Thailand and have ancient phylogenetic connections to the rest of the group. A relaxed molecular clock analysis with these new taxa dates the origin of porcini to between 42 and 54 million years ago, coinciding with the initial diversification of angiosperms, during the Eocene epoch when the climate was warm and humid. These results reveal an unexpected diversity, distribution, and ancient origin of a group of commercially valuable mushrooms that may provide an economic incentive for conservation and support the hypothesis of a tropical origin of the ectomycorrhizal symbiosis.}, keywords = {PHYLOGENY}, doi = {10.1016/j.ympev.2010.10.004}, author = {Dentinger, Bryn T.M. and Ammirati Jr., Joseph Frank and Both, Ernst E. and Desjardin, Dennis E. and Halling, Roy E. and Henkel, Terry W. and Moreau, Pierre-Arthur and Nagasawa, Eiji and Soytong, Kasem and Taylor, Andy F.} } @article {70300, title = {Measurement of atmospheric sesquiterpenes by proton transfer reaction-mass spectrometry (PTR-MS)}, journal = {Atmospheric Measurement Techniques Discussions}, volume = {2}, year = {2009}, month = {2009}, pages = {99 - 112}, abstract = {The ability to measure sesquiterpenes (SQT; C15H24) by a Proton-Transfer-Reaction Mass Spectrometer (PTR-MS) was investigated. SQT calibration standards were prepared by a capillary diffusion method and the PTR-MS-estimated mixing ratios were derived from the counts of product ions and proton transfer reaction constants. These values were compared with mixing ratios determined by a calibrated Gas Chromatograph (GC) coupled to a Flame Ionization Detector (GC-FID). Product ion distributions from soft-ionization occurring in a selected ion drift tube via proton transfer were measured as a function of collision energies. Results after the consideration of the mass discrimination of the PTR-MS system suggest that quantitative SQT measurements within 20\% accuracy can be achieved with PTR-MS if two major product ions (m/z 149+ and 205+), out of seven major product ions (m/z 81+, 95+, 109+, 123+, 135+, 149+ and 205+), are accounted for. Considerable fragmentation of bicyclic sesquiterpenes, i.e. β-caryophyllene and α-humulene, cause the accuracy to be reduced to 50\% if only the parent ion (m/z 205+) is considered. These findings were applied to a field dataset collected above a deciduous forest at the PROPHET (Program for Research on Oxidants: Photochemistry, Emissions, and Transport) research station in 2005. Inferred average daytime ecosystem scale mixing ratios (fluxes) of isoprene, sum of monoterpenes (MT), and sum of SQT exhibited values of 15 μg m-3 (4.5 mg m-2 h-1), 1.2 μg m-3 (0.21 mg m-2 h-1), and 0.0016 μg m-3 (0.10 mg m-2 h-1), respectively. A range of MT and SQT reactivities with respect to the OH radical was calculated and compared to an earlier study inferring significantly underestimated OH reactivities due to unknown terpenes above this deciduous forest. The results indicate that incorporating these MT and SQT results can resolve ~30\% of missing OH reactivity reported for this site.}, keywords = {VOLATILE ORGANIC COMPOUNDS}, doi = {10.5194/amt-2-99-2009}, author = {Kim, S. and Karl, T. and Helmig, D. and Daly, R. and Rasmussen, R. and Guenther, A.} } @article {70304, title = {The MODIS (Collection V005) BRDF/albedo product: Assessment of spatial representativeness over forested landscapes}, journal = {Remote Sensing of Environment}, volume = {113}, year = {2009}, month = {11/2009}, pages = {2476 - 2498}, abstract = {A new methodology for establishing the spatial representativeness of tower albedo measurements that are routinely used in validation of satellite retrievals from global land surface albedo and reflectance anisotropy products is presented. This method brings together knowledge of the intrinsic biophysical properties of a measurement site, and the surrounding landscape to produce a number of geostatistical attributes that describe the overall variability, spatial extent, strength of the spatial correlation, and spatial structure of surface albedo patterns at separate seasonal periods throughout the year. Variogram functions extracted from Enhanced Thematic Mapper Plus (ETM+) retrievals of surface albedo using multiple spatial and temporal thresholds were used to assess the degree to which a given point (tower) measurement is able to capture the intrinsic variability of the immediate landscape extending to a satellite pixel. A validation scheme was implemented over a wide range of forested landscapes, looking at both deciduous and coniferous sites, from tropical to boreal ecosystems. The experiment focused on comparisons between tower measurements of surface albedo acquired at local solar noon and matching retrievals from the MODerate Resolution Imaging Spectroradiometer (MODIS) (Collection V005) Bidirectional Reflectance Distribution Function (BRDF)/albedo algorithm. Assessments over a select group of field stations with comparable landscape features and daily retrieval scenarios further demonstrate the ability of this technique to identify measurement sites that contain the intrinsic spatial and seasonal features of surface albedo over sufficiently large enough footprints for use in modeling and remote sensing studies. This approach, therefore, improves our understanding of product uncertainty both in terms of the representativeness of the field data and its relationship to the larger satellite pixel.}, keywords = {SPATIAL}, doi = {10.1016/j.rse.2009.07.009}, author = {Rom{\'a}n, Miguel O. and Schaaf, Crystal B. and Woodcock, Curtis E. and Strahler, Alan H. and Yang, Xiaoyuan and Braswell, Rob H. and Curtis, Peter S. and Davis, Kenneth J. and Dragoni, Danilo and Goulden, Mike and Gu, Lianhong and Hollinger, David and Kolb, Thomas and Meyers, Tilden and Munger, J. William and Privette, Jeffrey L. and Richardson, Andrew D. and Wilson, Tim B. and Wofsy, Steve} } @article {70305, title = {Passerine Breeding and Post-Fledgling Habitat Use in Riparian and Upland Temperate Forests of the American Midwest}, journal = {The Condor}, volume = {111}, year = {2009}, note = {The University of Michigan Biological Station{\textquoteright}s Vaden \& Maxine Miles Fund provided a portion of the research funds}, month = {11/2009}, pages = {756 - 762}, abstract = {Riparian forests are thought to be important habitat for fledglings in a diversity of temperate-forest passerines, yet few studies have examined this hypothesis. The main objective of this study, conducted in temperate deciduous forests in Michigan{\textquoteright}s Lower Peninsula, was to compare bird use of riparian and upland forests during and after breeding. Using mist-nets, we quantified populations in accordance with the Monitoring Avian Productivity and Survivorship (MAPS) protocol. Nets were set up in both riparian and upland forests in a paired sampling design. After fledging, we captured juveniles, including those of the Ovenbird (Seiurus aurocapilla), at a rate higher in riparian than in upland forests. The trend for adult Ovenbirds was similar. For riparian breeders, we found no difference in capture rates over time between upland and riparian forests; these species appeared to stay in riparian forests after fledging. Our results suggest that riparian forests are important habitat for passerines during the period following fledging; they need to be considered accordingly during conservation planning.}, keywords = {SEIURUS}, doi = {10.1525/cond.2009.080059}, author = {Akresh, Michael E. and Dinse, Keely and Foufopoulos, Johannes and Schubel, Stephanie C. and Kowalczyk, Theresa} } @article {70314, title = {Whole-ecosystem labile carbon production in a north temperate deciduous forest}, journal = {Agricultural and Forest Meteorology}, volume = {149}, year = {2009}, month = {09/2009}, pages = {1531 - 1540}, abstract = {Labile carbon (C), which is principally comprised of non-structural carbohydrates, is an essential intermediary between C assimilation and structural growth in deciduous forests. We developed a new approach that combined meteorological and biometric C cycling data for a mixed deciduous forest in Michigan, USA, to provide novel estimates of whole-ecosystem labile C production and reallocation to structural net primary production (NPP). We substantiated inferred seasonal patterns of labile C production and reallocation to structural NPP with measurements of Populus grandidentata and Quercus rubra wood non-structural carbohydrate concentration and mass over two years. Our analysis showed that 55\% of annual net canopy C assimilate (Ac) was first allocated to labile C production rather than to immediate structural NPP. Labile C produced during the latter half of summer later supported dormant-season structural growth and respiration, with 34\% of structural NPP in a given year requiring labile C stored during previous years. Seasonal changes in wood non-structural carbohydrate concentration and mass generally corroborated inferred temporal patterns of whole-ecosystem labile C production and reallocation to structural NPP. Our findings confirm that disparities can arise between same-year meteorological and biometric net ecosystem production when meteorologically measured C assimilation and biometrically measured growth are asynchronous because of temporary photosynthate allocation to labile C storage. We conclude that a broader understanding of labile C production and reallocation at the ecosystem scale is important to interpreting lagged canopy C cycling and structural growth processes.}, keywords = {TIME LAGS}, doi = {10.1016/j.agrformet.2009.04.006}, author = {Gough, Christopher M. and Flower, Charles E. and Vogel, Christoph S. and Dragoni, Danilo and Curtis, Peter S.} } @article {70345, title = {Approaches for quantifying reactive and low-volatility biogenic organic compound emissions by vegetation enclosure techniques {\textendash} Part B: Applications}, journal = {Chemosphere}, volume = {72}, year = {2008}, month = {06/2008}, pages = {365 - 380}, abstract = {The focus of the studies presented in the preceding companion paper (Part A: Review) and here (Part B: Applications) is on defining representative emission rates from vegetation for determining the roles of biogenic volatile organic compound (BVOC) emissions in atmospheric chemistry and aerosol processes. The review of previously published procedures for identifying and quantifying BVOC emissions has revealed a wide variety of experimental methods used by various researchers. Experimental details become increasingly critical for quantitative emission measurements of low volatility monoterpenes (MT) and sesquiterpenes (SQT). These compounds are prone to be lost inadvertently by uptake to materials in contact with the sample air or by reactions with atmospheric oxidants. These losses become more prominent with higher molecular weight compounds, potentially leading to an underestimation of their emission rates. We present MT and SQT emission rate data from numerous experiments that include 23 deciduous tree species, 14 coniferous tree species, 8 crops, and 2 shrubs. These data indicate total, normalized (30 degrees C) basal emission rates from <10 to 5600 ngC g^-1 h^-1 for MT, and from <10 to 1150 ngC g^-1 h^-1 for SQT compounds. Both MT and SQT emissions have exponential dependencies on temperature (i.e. rates are proportional to e^BT). The inter-quartile range of B-values for MT was between 0.12 and 0.17 K^-1 , which is higher than the value commonly used in models (0.09 K^-1). However many of the MT emissions also exhibited light dependencies, making it difficult to separate light and temperature influences. The primary light-dependent MT was ocimene, whose emissions were up to a factor of 10 higher than light-independent MT emissions. The inner-quartile range of B-values for SQT was between 0.15 and 0.21 K^-1}, keywords = {VOLATILE ORGANIC COMPOUNDS}, doi = {10.1016/j.chemosphere.2008.02.054}, author = {Ortega, John and Helmig, Detlev and Daly, Ryan W. and Tanner, David M. and Guenther, Alex B. and Herrick, Jeffrey D.} } @article {70366, title = {Influence of vegetation and seasonal forcing on carbon dioxide fluxes across the Upper Midwest, USA: implications for regional scaling}, journal = {Agicultural and Forest Meteorology}, volume = {148}, year = {2008}, pages = {288-308}, abstract = {Carbon dioxide fluxes were examined over the growing seasons of 2002 and 2003 from 14 different sites in Upper Midwest (USA) to assess spatial variability of ecosystemvatmosphere CO2 exchange. These sites were exposed to similar temperature/precipitation regimes and spanned a range of vegetation types typical of the region (northern hardwood, mixed forest, red pine, jack pine, pine barrens and shrub wetland). The hardwood and red pine sites also spanned a range of stand ages (young, intermediate, mature). While seasonal changes in net ecosystem exchange (NEE) and photosynthetic parameters were coherent across the 2 years at most sites, changes in ecosystem respiration (ER) and gross ecosystem production (GEP) were not. Canopy height and vegetation type were important variables for explaining spatial variability of CO2 fluxes across the region. Light-use efficiency (LUE) was not as strongly correlated to GEP as maximum assimilation capacity (Amax). A bottom-up multi-tower land cover aggregated scaling of CO2 flux to a 2000 km2 regional flux estimate found June to August 2003 NEE, ER and GEP to be 290 89, 408 48, and 698 73 gC m2, respectively. Aggregated NEE, ER and GEP were 280\% larger, 32\% smaller and 3\% larger, respectively, than that observed from a regionally integrating 447m tall flux tower. However, when the tall tower fluxes were decomposed using a footprint-weighted influence function and then reaggregated to a regional estimate, the resulting NEE, ER and GEP were within 11\% of the multi-tower aggregation. Excluding wetland and young stand age sites from the aggregation worsened the comparison to observed fluxes. These results provide insight on the range of spatial sampling, replication, measurement error and land cover accuracy needed for multi-tiered bottom-up scaling of CO2 fluxes in heterogeneous regions such as the Upper Midwest, USA.}, keywords = {UPSCALING}, author = {Desai, Ankur R. and Noormets, Asko and Bolstad, Paul V. and Chen, Jiquan and Cook, Bruce D. and Davis, Kenneth J. and Euskirchen, Eugenie S. and Gough, Christopher M. and Martin, Jonathan G. and Ricciuto, Daniel M. and Schmid, Hans Peter and Tang, Jianwu and Wang, Weiguo} } @article {70353, title = {Moisture sensitivity of ecosystem respiration: Comparison of 14 forest ecosystems in the Upper Great Lakes Region, USA}, journal = {Agricultural and Forest Meteorology}, volume = {148}, year = {2008}, month = {02/2008}, pages = {216 - 230}, abstract = {Ecosystem respiration (ER) was measured with the eddy covariance technique in 14 forest ecosystems in the Upper Great Lakes Region during the growing seasons of 2002 and 2003. The response of ER to soil temperature and moisture was analyzed using empirical models. On average, ER was higher in the intermediate and young than in the mature stands, and higher in hardwood than in conifer stands. The seasonal mean temperature-normalized respiration rate (R10) ranged from 1 to 3 μmol CO2 m-2 s-1 and seasonal mean activation energy (Ea) from 40 to 110 kJ mol-1. The variation in the residuals of temperature response function of ER was best explained by soil moisture content. ER showed higher temperature sensitivity (as indicated by lower Ea) in the young than in the mature stands of coniferous forests, but not in the hardwood forests. The inclusion of soil moisture as an explicit driver of R10 explained an additional 8\% (range 0{\textendash}21\%) of variability in ER. Significant moisture sensitivity of ER was detected in only 5 out of 20 site-years and it was associated with bimodal soil moisture distribution. Moisture sensitivity could partially be predicted from statistical moments kurtosis and interquartile range. The data implied greater moisture sensitivity with increasing stand age, possibly due to faster depletion of soil water supplies from a greater evaporative surface in the older stands. Additional limiting factors to ER were implicated.}, keywords = {SOILS}, doi = {10.1016/j.agrformet.2007.08.002}, author = {Noormets, Asko and Desai, Ankur R. and Cook, Bruce D. and Euskirchen, Eugenie S. and Ricciuto, Daniel M. and Davis, Kenneth J. and Bolstad, Paul V. and Schmid, Hans Peter and Vogel, Christoph S. and Carey, E.V. and Su, H.B. and Chen, J.} } @article {70349, title = {Sesquiterpene emissions from vegetation: a review}, journal = {Biogeosciences}, volume = {5}, year = {2008}, note = {The University of Michigan Biological Station{\textquoteright}s Biosphere-Atmosphere Research Training (BART) program is acknowledged. BART was part of NSF{\textquoteright}s IGERT program.}, month = {05/2008}, pages = {761 - 777}, abstract = {This literature review summarizes the environmental controls governing biogenic sesquiterpene (SQT) emissions and presents a compendium of numerous SQT-emitting plant species as well as the quantities and ratios of SQT species they have been observed to emit. The results of many enclosure-based studies indicate that temporal SQT emission variations appear to be dominated mainly by ambient temperatures although other factors contribute (e.g., seasonal variations). This implies that SQT emissions have increased significance at certain times of the year, especially in late spring to mid-summer. The strong temperature dependency of SQT emissions also creates the distinct possibility of increasing SQT emissions in a warmer climate. Disturbances to vegetation (from herbivores and possibly violent weather events) are clearly also important in controlling short-term SQT emissions bursts, though the relative contribution of disturbance-induced emissions is not known. Based on the biogenic SQT emissions studies reviewed here, SQT emission rates among numerous species have been observed to cover a wide range of values, and exhibit substantial variability between individuals and across species, as well as at different environmental and phenological states. These emission rates span several orders of magnitude (10s{\textendash}1000s of ng gDW-1 h-1). Many of the higher rates were reported by early SQT studies, which may have included artificially-elevated SQT emission rates due to higher-than-ambient enclosure temperatures and disturbances to enclosed vegetation prior to and during sample collection. When predicting landscape-level SQT fluxes, modelers must consider the numerous sources of variability driving observed SQT emissions. Characterizations of landscape and global SQT fluxes are highly uncertain given differences and uncertainties in experimental protocols and measurements, the high variability in observed emission rates from different species, the selection of species that have been studied so far, and ambiguities regarding controls over emissions. This underscores the need for standardized experimental protocols, better characterization of disturbance-induced emissions, screening of dominant plant species, and the collection of multiple replicates from several individuals within a given species or genus as well as a better understanding of seasonal dependencies of SQT emissions in order to improve the representation of SQT emission rates.}, keywords = {VOLATILE ORGANIC COMPOUNDS}, doi = {10.5194/bg-5-761-2008}, author = {Duhl, T. R. and Helmig, D. and Guenther, A.} } @mastersthesis {70399, title = {Methylmercury in fish: accumulation, toxicity, and temporal trends}, volume = {Doctor of Philosophy}, year = {2007}, note = {Chapter 5, Appendix B is titled: No seasonal trend in mercury concentration of Great Lakes region northern pike. He found that there are two distinct groups of pike in Douglas Lake: small ones with high mercury concentrations and bigger ones with lower concentrations.}, pages = {105 pp.}, school = {Miami University}, address = {Oxford, OH}, abstract = {Mercury contamination of fish is a serious problem, and consideration of policy options for a solution requires answering two questions. (1) What is the evidence that fish are being adversely affected by mercury? (2) How would mercury concentrations in fish respond to reduced anthropogenic emissions of mercury? I performed research integral to answering these questions. First, I studied mercury accumulation in northwest Atlantic sea lamprey, an agnathan fish. I discovered there are fundamental differences in mercury accumulation between sea lamprey and teleosts. All life stages of sea lamprey are exposed to high concentrations of mercury. More research should be directed towards understanding mercury contamination of diverse groups of fishes and its toxicological effects. Second, I studied the toxicological mechanisms of methylmercury in fish. Exposure to methylmercury impairs the reproduction of fish, and previous research has linked impaired reproductin in fish to the suppression of sex steroid hormones. I exposed fathead minnows to dietary methylmercury to test the hypothesis that methylmercury induces apoptosis in steroidogenic cells in fish, thereby interfering with the synthesis of sex steroid hormones. Methylmercury increased the number of apoptotic follicular cells in ovarian follicles, which in turn was related to suppressed 17B-estradiol concentrations in females. These results ultimately suggest apoptosis of steroidogenic cells as a mechanism for the impairment of reproduction in fish exposed to methylmercury. Third, I studied the resopnse of mercury contamination in fish to changing atmospheric pollution. Serendipitously, I discovered a decline during the past decade in mercury concentrations in fish at Isle Royale, USA. Changes in mercury source have not caused the decline, as deposition has reamined stable during the past decade. I examined sulfur concentrations in lake sediments to test the hypothesis that declines in sulfate deposition have resulted in less methylation of mercury and thus less mercury in fish. Results indicated mercury concentrations in fish are primarily a function of sulfate deposition. In sum, (1) fish are adversely affected by methylmercury and (2) mercury concentrations in fish will decline in response to reduced anthropogenic emissions of mercury and sulfur.}, keywords = {TOXINS}, author = {Drevnick, Paul E.} } @article {70400, title = {Observing succession on aspen-dominated landscapes using a remote sensing-ecosystem approach}, journal = {Landscape Ecology}, volume = {22}, year = {2007}, pages = {1395-1410}, abstract = {In the North American upper Great Lakes region, forests dominated by the aspens (Populus grandidentata Michx. v bigtooth aspen, and P. tremuloides Michx. v trembling aspen), which established after late 19th and early 20thcentury logging, are maturing and succession will create a new forest composition at landscape toregional scales. This study analyzed the capabilities of Landsat ETM+ remote sensing data combined with existing ecological land unit classifications to discriminate and quantify patterns of succession at the landscape scale over the 4200 ha University of Michigan Biological Station (UMBS) in northern Lower Michigan. In a hierarchical approach first multi-temporal Landsat ETM+ was used with a landscape ecosystem classification to map upland forest cover types (overall accuracy 91.7\%). Next the aspen cover type was subset and successional pathways were mapped within that type (overall accuracy 89.8\%). Results demonstrated that Landsat ETM+may be useful for these purposes; stratification of upland from wetland types using an ecological land unit classification eliminated confounding issues; multi-temporal methods discriminated evergreen conifer versus deciduous understories. The Landsat ETM+ classifications were then used to quantify succession and its relationship to landform-level ecological land units. Forests on moraine and ice contact landforms are succeeding distinctly to northernhardwoods (95\% and 88\% respectively); those on outwash and other landforms show greater diversity of successional pathways.}, keywords = {TSUGA}, author = {Bergen, Kathleen M. and Dronova, Iryna} } @article {70401, title = {Prenatal cannibalism in an insect}, journal = {Naturwissenschaften}, volume = {94}, year = {2007}, pages = {477-482}, abstract = {Host selection and infection strategies of parasitoids often correlate with high parental investment and low numbers of progeny. In this study, we investigate how additional internal mechanisms might shape brood size and fitness of the offspring. Emblemasoma auditrix is a parasitoid fly in which about 38 larvae hatch simultaneously in utero. After host location, a single larva is deposited into the host, where it rapidly develops and pupates after about 5 days. The search for hosts can take several weeks, and during that time, the larvae arrest their development and remain in the first larval instar. Nevertheless, the larvae increase in weight within the uterus, and this growth correlates to a decrease in the number of larvae, although no larvae are deposited. Thus, our data indicate a first case of prenatal cannibalism in an invertebrate with larvae feeding on each other within the uterus of the adult.}, keywords = {SURVIVAL}, doi = {10.1007/s00114-006-0213-z}, author = {de Vries, Thomas and Lakes-Harlan, Reinhard} } @article {70380, title = {Sesquiterpene Emissions from Pine Trees - Identifications, Emission Rates and Flux Estimates for the Contiguous United States}, journal = {Environmental Science \& Technology}, volume = {41}, year = {2007}, note = {Lists "University of Michigan Biological Station (UMBS), Pellston, MI" in Research Sites and Acknowledgments.}, month = {03/2007}, pages = {1545 - 1553}, abstract = {Biogenic volatile organic compound (BVOC) emissions were studied using vegetation enclosure experiments. Particular emphasis was given to sesquiterpene compounds (SQT), although monoterpenes (MT) were also characterized. SQT were detected in emissions from seven (out of eight) pine species that were examined. Thirteen SQT compounds were identified; the most abundant ones were β-caryophyllene, α-bergamotene, β-farnesene, and α-farnesene, with emission rates increasing exponentially with temperature. Regression analysis yielded exponential dependencies of both MT and SQT emissions on temperature of the form E = E$_{0}$ {\texttimes} exp(β(T - T$_{0}$)). This resulted in SQT basal emission rates (E$_{0}$ defined at T$_{0}$ = 30 {\textdegree}C) ranging between <4 and 620 ng (carbon) gdw-1 h-1 (gdw = gram dry weight). The average value of the exponential temperature response factor β for SQT emissions, taken from all experiments, was 0.17 {\textdegree}C$^{-}${\textonesuperior}, whereas the value for monoterpenes was 0.11 {\textdegree}C$^{-}${\textonesuperior}. The average, total SQT emissions from pines were estimated to be 9, 16, and 29\% of the MT emissions at 20, 30, and 40 {\textdegree}C respectively. The emission factors and β-factors determined from these measurements were used to estimate pine tree MT and SQT emission distributions for the contiguous United States using MEGAN (model of emissions of gases and aerosols from nature, Guenther et al., 2006). SQT fluxes reaching 10-40 mg m$^{-}${\texttwosuperior} for the month of July were estimated for extensive areas of most western and southern U.S. states.}, keywords = {VOLATILE ORGANIC COMPOUNDS}, doi = {10.1021/es0618907}, author = {Helmig, Detlev and Ortega, John and Duhl, Tiffany and Tanner, David and Guenther, Alex and Harley, Peter and Wiedinmyer, Christine and Milford, Jana and Sakulyanontvittaya, Tanarit} } @article {70410, title = {Do Increasing Cormorant Populations Threaten Sportfishes in the Great Lakes? A Case Study in Lake Huron}, journal = {Journal of Great Lakes Research}, volume = {32}, year = {2006}, month = {06/2006}, pages = {306 - 320}, abstract = {After near extirpation earlier this century in the Great Lakes, double-crested cormorant (Phalacrocorax auritus) populations reached all-time highs, raising concerns among sport anglers and fisheries managers, who see cormorants as a significant source of mortality for yellow perch (Perca flavescens), whose populations are perceived to have declined in concert with cormorant increases. We partitioned age-specific perch mortality for 1995 into that caused by (1) cormorant predation, (2) angler harvest, and (3) other sources. Cormorant consumption of perch was calculated by simultaneously estimating diet composition (using stomach analysis and number of foraging cormorants from aerial and ground surveys), and daily consumption (using energetic values from the literature). Consumption of perch by cormorants was heaviest during April and May (48\% of the diet by weight) when perch spawn, but yellow perch was not an important prey species overall (11\%). Primary prey groups were alewife (47\%) and sticklebacks (15\%). Cormorants consumed 11,400 kg of perch, mostly young fish (ages 1{\textendash}3), but mortality caused by cormorant predation was estimated at <= 6.3\% of mortality for all ages of perch. Neither cormorants nor anglers contributed more than one-fourth of the total annual mortality of any age class of perch. Although cormorants were highly visible predators of perch in Les Cheneaux Islands area, they did not represent a major source of mortality in 1995. Impact of cormorants on perch may vary from year to year, and may relate to fluctuations in timing of the birds{\textquoteright} migration relative to perch spawning. However, we conclude that overall impact is not significant, and control measures to limit their populations were not warranted at the time of this study.}, keywords = {STICKLEBACKS}, doi = {10.3394/0380-1330(2006)32[306:DICPTS]2.0.CO;2}, author = {Diana, James S. and Maruca, Susan L. and Low, Bobbi S.} } @mastersthesis {70417, title = {Sinnes- und Verhaltnesokologie der parasitoiden Fliege Emblemasoma auditrix (Diptera: Sarcophagidae)}, volume = {Doctor of Philosophy}, year = {2006}, school = {Justus-Liebig-Universitat Giessen}, address = {Giessen, Deutschland}, keywords = {SOUND}, author = {de Vries, Thomas} } @inbook {70439, title = {Atmospheric Mercury: A Decade of Observations in the Great Lakes}, booktitle = {Dynamics of Mercury Pollution on Regional and Global Scales: Atmospheric Processes and Human Exposures Around the World}, volume = {XII}, year = {2005}, pages = {611-636}, publisher = {Springer}, organization = {Springer}, address = {New York, NY}, keywords = {MERCURY}, isbn = {978-0-387-24493-8}, author = {Keeler, Gerald J. and Dvonch, Timothy J.}, editor = {Pirrone, Nicola and Mahaffey, Kathryn R.} } @article {70446, title = {Atmospheric nitrate deposition and enhanced dissolved organic carbon leaching: test of a potential mechanism}, journal = {Soil Science Society of America Journal}, volume = {69}, year = {2005}, note = {Jared often stayed here to do this work.}, pages = {1233-1237}, abstract = {Atmospheric NO3- deposition has the potential to disrupt litter decomposition in temperate forests by suppressing enzymes responsible for lignin degradation. A reduction in phenol oxidase activity could potentially trigger an increase in soluble phenolic compounds, which in turn are known to decrease the activity of cellulolytic enzymes like B-glucosidase. Our study investigated whether the inhibition of lignin degradation by experimental NO3- deposition could increase soluble phenolics in soil, suppress B-Glucosidase activity, and potentially explain a greater export of dissolved organic C (DOC) from northern hardwood ecosystems. We found no evidence that the suppression of phenol oxidase by NO3- additions increased soluble phenolics in mineral soil, nor did we find a strong inverse relationship between soluble phenolics and B-glucosidase activity. It appears that reductions in mineral soil lignolytic activity induced by experimental deposition are not responsible for greater DOC export from soil.}, keywords = {TREES}, author = {DeForest, Jared L. and Zak, Donald R. and Pregitzer, Kurt S. and Burton, Andrew James} } @article {70460, title = {Phonotaxis of the female parasitoid Emblemasoma auditrix (Diptera, Sarcophagidae) in relation to number of larvae and age}, journal = {Zoology}, volume = {108}, year = {2005}, note = {Also field sites near Grayling (17 km E) and Luzerne (3 km W).}, pages = {239-246}, abstract = {The dipteran parasitoid Emblemasoma auditrix locates its host acoustically. Analysis showed that phonotactic female flies usually carry fully developed larvae within their uteri. The mean number of larvae per female at the beginning of the season was 37.9 (range from 10 to 50). The number of larvae decreased rapidly with increasing singing activity of the host cicada (Okanagana rimosa). In high-density host populations the parasitoid is likely to become egg-limited. A possible selective phonotactic responsiveness depending on the number of larvae or the age of the female was tested with song models. Phonotaxis depended on both the temporal structure and the frequency content, but in the field no correlation was found between the number of larvae and the preferences for the acoustic signal. Experiments in the laboratory showed that flies without host contact broadened their phonotactic stimulus range with age.}, keywords = {SOUND}, author = {de Vries, Thomas and Lakes-Harlan, Reinhard} } @article {70481, title = {Atmospheric nitrate deposition and the microbial degradation of cellobiose and vanillin in a northern hardwood forest}, journal = {Soil Biology and Biochemistry}, volume = {36}, year = {2004}, note = {Jared often stayed here to do this work.}, pages = {965-971}, abstract = {Human activity has increased the amount of N entering terrestrial ecosystems from atmospheric NO3 deposition. High levels of inorganic N are known to suppress the expression of phenol oxidase, an important lignin-degrading enzyme produced by white-rot fungi. We hypothesized that chronic NO3 additions would decrease the flow of C through the heterotrophic soil food web by inhibiting phenol oxidase and the depolymerization of lignocellulose. This would likely reduce the availability of C from lignocellulose for metabolism by the microbial community. We tested this hypothesis in a mature northern hardwood forest in northern Michigan, which has received experimental atmospheric N deposition (30 kg NO3vN ha y) for nine years. In a laboratory study, we amended soils with 13C-labeled vanillin, a monophenolic product of lignin depolymerization, and 13C-labeled cellobiose, a disaccharide product of cellulose degradation. We then traced the flow of 13C through the microbial community and into soil organic carbon (SOC), dissolved organic carbon (DOC), and microbial respiration. We simultaneously measured the activity of enzymes responsible for lignin (phenol oxidase and peroxidase) and cellobiose (b-glucosidase) degradation. Nitrogen deposition reduced phenol oxidase activity by 83\% and peroxidase activity by 74\% when compared to control soils. In addition, soil C increased by 76\%, whereas microbial biomass decreased by 68\% in NO3 amended soils. 13C cellobiose in bacterial or fungal PLFAs was unaffected by NO3 deposition; however, the incorporation of 13C vanillin in fungal PLFAs extracted from NO3 amended soil was 82\% higher than in the control treatment. The recovery of 13C vanillin and 13C cellobiose in SOC, DOC, microbial biomass, and respiration was not different between control and NO3 amended treatments. Chronic NO3 deposition has stemmed the flow of C through the heterotrophic soil food web by inhibiting the activity of ligninolytic enzymes, but it increased the assimilation of vanillin into fungal PLFAs.}, keywords = {TREES}, author = {DeForest, Jared L. and Zak, Donald R. and Pregitzer, Kurt S. and Burton, Andrew James} } @article {70482, title = {Atmospheric nitrate deposition, microbial community composition, and enzyme activity in northern hardwood forests}, journal = {Soil Science Society of America Journal}, volume = {68}, year = {2004}, note = {Jared often stayed here to do this work.}, pages = {132-138}, abstract = {On a global scale, human activity has increased the atmospheric input of NO3- to many terrestrial ecosystems. Anthropogenic NO3- may be a potent modifier of ecosystem function, especially in temperate forests that are sometimes N limited. However, the impact of chronic N deposition on soil microorganisms is still poorly understood. Nitrate entering Lake States forests is rapidly assimilated by the microbial community and it is subsequently released as NH4+. Because high levels of NH4+ inhibit the activity of lignin-degrading soil fungi, we reasoned that chronic N additions could alter the composition and function of heterotrophic microbial communities in soil, and hence the ecosystem-level processes they mediate. We tested our hypothesis in four northern hardwood ecosystems in northern Michigan, which received experimental N additions (30 kg NO3-/ha/yr)during the past 8 yr. We quantified microbial community function by measuring the activity of extracellular enzymes involved in plant litter degradation and described microbial community composition using phospholipid fatty acid (PFLA) analysis. Chronic N additions significantly suppressed B-glucosidase activity by 24\% in mineral soil and suppressed phenol oxidase activity by 35\% in surface litter. We found no evidence that chronic N additions altered microbial community composition; NO3- addition did not alter the relative abundance of bacterial, actinomycetal, fungal, or protozoan PFLAs. However, NO3- additions significantly reduced microbial biomass by 18\% relative to the control treatment. Results indicate that N additions broadly suppressed all microbial groups, not just the activity and abundance of lignin-degrading fungi.}, keywords = {TREES}, author = {DeForest, Jared L. and Zak, Donald R. and Pregitzer, Kurt S. and Burton, Andrew James} } @mastersthesis {70488, title = {Elevated atmospheric NO3- deposition in northern hardwood forests: impacts on the microbial mechanisms of plant litter decomposition}, volume = {Doctor of Philosophy}, year = {2004}, note = {Jared often stayed here to do this work. Michigan Gradient Study Plot Northern Hardwoods}, pages = {94 pp.}, school = {University of Michigan}, address = {Ann Arbor, MI}, keywords = {TREES}, author = {DeForest, Jared L.} } @article {70473, title = {Missing OH reactivity in a forest: evidence for unknown reactive biogenic VOCs}, journal = {Science}, volume = {304}, year = {2004}, month = {04/2004}, pages = {722-725}, abstract = {Forest emissions of biogenic volatile organic compounds (BVOCs), such as isoprene and other terpenes, play a role in the production of troposhperic ozone and aerosols. In a northern Michigan forest, the direct measurement of total OH reactivity, which is the inverse of the OH lifetime, was significantly greater than expected. The difference between measured and expected OH reactivity, called the missing OH reactivity, increased with temperature, as did emission rates for terpenes and other BVOCs. These measurements are consistent with the hypothesis that unknown reactive BVOCs, perhaps terpenes, provide the missing OH reactivity.}, keywords = {VEGETATION}, doi = {10.1126/science.1094392}, author = {Di Carlo, Piero and Brune, William H. and Martinez, Monica and Harder, Hartwig and Lesher, Robert and Ren, Xinrong and Thornberry, Troy Dean and Carroll, Mary Anne and Young, Valerie and Shepson, Paul B. and Riemer, Daniel D. and Apel, Eric C. and Campbell, Colleen} } @mastersthesis {70471, title = {Real-time measurements of non-refractory particle composition and interactions at forested sites}, volume = {Doctor of Philosophy}, year = {2004}, month = {05/2004}, pages = {159 pp.}, school = {University of Colorado}, type = {PhD Dissertation}, address = {Boulder, CO}, abstract = {Aerosols can have a significant influence on air quality, visibility, health, and regional and global climate. As is evident from the Intergovernmental Panel on Climate Change report [2001], the effect of aerosols on climate are the most uncertain, could be positive or negative depending on the chemical composition, can have secondary effects that are poorly understood, and could be as large as that of the greenhouse gases. However, aerosol properties are difficult to measure because there is so much variability in size, composition, and other properties. The more local effects, such as air quality, visibility, and health, are also difficult to determine because aerosols are strongly influenced by local conditions as well as long-range transport. Currently, there are no instruments capable of measuring all aerosol properties, either in-situ or remotely. Most measurements are restricted to a certain size range, to only one property, or multiple properties (e.g., an impactor with size and chemical composition) with low time resolution. In 1999, the Aerosol Mass Spectrometer (AMS) developed by Aerodyne Research, Inc., was deployed for the first time in the Atlanta Supersites Project. The AMS provides real time in-situ quantitative chemical composition and size data of submicron non-refractory aerosols. The compositional information is obtained with standard quadrupole mass spectrometry and the size data by particle time of flight across a vacuum chamber. Particles are first vaporized, typically at a temperature of approximately 600 {\textdegree}C, and then ionized by electron impact before being analyzed by the quadrupole mass spectrometer. It is this separation of vaporization and ionization that allows the AMS to produce quantitative data. During the last four years, the AMS has progressed from a pilot instrument with several unresolved issues to a self-sufficient, tested, instrument that provides more complete information about fine aerosols than most other instruments. This thesis presents the operation and development of the Aerodyne Research Aerosol Mass Spectrometer (AMS) and results from several field campaigns. The main focus will be two large field campaigns at which the AMS was deployed, PROPHET 2001 at the University of Michigan Biological Station in northern Michigan and CELTIC 2003 at Duke Forest in North Carolina, are both located in forested areas. The PROPHET site is truly a remote site with no large population centers nearby while CELTIC is located just outside Raleigh, North Carolina, and has a much larger urban influence. Aerosol properties at the PROPHET site are clearly dependent on wind direction, with large concentrations of aged, processed aerosols dominated by sulfate arriving from the south and low concentrations dominated by organic species arriving from the less populated region to the north. Aerosols at the CELTIC site are more of a mixture due to the variety of nearby sources, although large changes in air masses are also clearly apparent. These measurements characterize the aerosols at a particular location, indicate the level of processing the aerosols have undergone and provide some information about sources.}, author = {Delia, Alice Elizabeth} } @article {70536, title = {Belowground carbon allocation in forests estimated from litterfall and IRGA-based soil respiration measurements}, journal = {Agricultural and Forest Meteorology}, volume = {113}, year = {2002}, pages = {39-51}, abstract = {Allocation of C to belowground plant structures is one of the most important, yet least well quantified fluxes of C in terrestrial ecosystems. In a literature review of mature forests worldwide, Raich and Nadelhoffer (1989) suggested that total belowground carbon allocation (TBCA) could be estimated from the difference between annual rates of soil respiration and aboveground litterfall. Here we analyze new measurements of soil respiration and litterfall, including data from the Ameriflux network. Our results generally agree with Raich and Nadelhoffer{\textquoteright}s previous work. A regression analysis of data from mature forests produced the following relationship: annual soil respiration = 287 + 2.80 x annual litterfall. This regression slope indicates that, on average, soil respiration is roughly three times aboveground litterfall-C, wich further implies that TBCA is roughly twice annual aboveground litterfall-C. These inferences are based on the uncertain assumption of soil C stocks being at steady state. Nevertheless, changes in soil C would have to be very large to modify the conclusion that TBCA is generally much larger than litterfall. Among only mature temperate hardwood forests, however, the correlation between litterfall and soil respiration was poor, and the correlation among years for a single site was also poor. Therefore, the regression cannot be relied upon to provide accurate estimates of soil respiration or TBCA for individual sites. Moreover, interannual variation in TBCA, short-term changes in C stocks, or different temporal scales controlling leaf litter production and soil respiration may cause important deviations from the global average. The regression slope for data from young forests is steeper, possibly indicating proportionally greater TBCA, but the steady-state assumption is more problematic for young forests. This method for estimating TBCA may be most appropriate where interannual variation is averaged over several years of observations and where a near-steady-state assumption of soil, litter, and root C stocks is least problematic.}, keywords = {SOILS}, author = {Davidson, E. A. and Savage, K. and Bolstad, Paul V. and Clark, D. A. and Curtis, Peter S. and Ellsworth, David S. and Hanson, Paul J. and Law, Beverly E. and Luo, Y. and Pregitzer, Kurt S. and Randolph, J. C. and Zak, Donald R.} } @article {70554, title = {The effect of 50 years of landscape change on species richness and community composition}, journal = {Global Ecology and Biogeography}, volume = {10}, year = {2001}, note = {Cheboygan and Emmet Counties}, pages = {305-313}, abstract = {We analyzed a 50-year dataset of avian species observations to determine how richness and community composition varied over a period of landscape-scale environmental change. Our study area, northern lower Michigan, has experienced substantial land-use and land-cover change over time. Like much of the northern Midwest, it has shifted from a largely unpopulated, post-logging shrubland toa moderately populated closed-canopy forest. Such changes are generally expected to influence overall richness and community composition. We found that regional richness per year remained virtually unchanged over the study period. Year-to-year variation in species number was surprisingly low. Richness totals included vastly different species groups as the composition of the regional bird community changed substantially over time. Changes in the types of species present appear to reflect deterministic changes in habitat. The number of grassland and open-habitat species decreased, for example, while species associated with older forests and urban habitats increased. Our results suggest that habitat changes at the landscape scale do not necessarily lead to changes in the number of species a region can support. Such changes, however, do appear to influence the types of species that will occupy a region, and can lead to substantial changes in community composition.}, keywords = {VARIATION}, author = {Parody, Jennifer M. and Cuthbert, Francesca Jean and Decker, Ethan H.} } @article {70569, title = {FLUXNET: a new tool to study the temporal and spatial variability of ecosystem-scale carbon dioxide, water vapor, and energy flux densities}, journal = {Bulletin of the American Meteorological Society}, volume = {82}, year = {2001}, pages = {2415-2434}, abstract = {FLUXNET is a global network of micrometeorological flux measurement sites that measure the exchanges of carbon dioxide, water vapor, and energy between the biosphere and atmosphere. At present over 140 sites are operating on a long-term and continuous basis. Vegetation under study includes temperate conifer and broadleaved (deciduous and evergreen) forests, tropical and boreal forests, crops, grasslands, chaparral, wetlands, and tundra. Sites exist on five continents and their latitudinal distribution ranges from 70+N to 30+S. FLUXNET has several primary functions. First, it provides infrastructure for compiling, archiving, and distributing carbon, water, and energy flux measurement, and meteorological, plant, and soil data to the science community. (Data and site information are available online at the FLUXNET Web site, http://www-eosdis.ornl.gov/FLUXNET/.) Second, the project supports calibration and flux intercomparison activities. This activity ensures that data from the regional networks are intercomparable. And third, FLUXNET supports the synthesis, discussion, and communication of ideas and data by supporting project scientists, workshops, and visiting scientists. The overarching goal is to provide information for validating computations of net primary productivity, evaporation, and energy absorption that are being generated by sensors mounted on the NASA Terra satellite. Data being compiled by FLUXNET are being used to quantify and compare magnitudes and dynamics of annual ecosystem carbon and water balances, to quantify the response of stand-scale carbon dioxide and water vapor flux densities to controlling biotic and abiotic factors, and to validate a hierarchy of soilvplantvatmosphere trace gas exchange models. Findings so far include 1) net CO2 exchange of temperate broadleaved forests increases by about 5.7 g C m-2 day-1 for each additional day that the growing season is extended; 2) the sensitivity of net ecosystem CO2 exchange to sunlight doubles if the sky is cloudy rather than clear; 3) the spectrum of CO2 flux density exhibits peaks at timescales of days, weeks, and years, and a spectral gap exists at the month timescale; 4) the optimal temperature of net CO2 exchange varies with mean summer temperature; and 5) stand age affects carbon dioxide and water vapor flux densities.}, keywords = {MICROMETEOROLOGY}, author = {Baldocchi, Dennis and Falge, Eva and Gu, Lianhong and Olson, Richard and Hollinger, David and Running, Steve and Anthoni, Peter and Bernhofer, Ch. and Davis, Kenneth J. and Evans, Robert and Fuentes, Jose and Goldstein, Allen and Katul, Gabriel and Law, Beverly E. and Lee, Zuhui and Malhi, Yadvinder and Meyers, Tilden and Munger, J. William and Oechel, Walt and Paw U, K. T. and Pilegaard, Kim and Schmid, Hans Peter and Valentini, Riccardo and Verma, Shashi and Vesala, Timo and Wilson, Kell B. and Wofsy, Steve} } @article {70572, title = {Hawkmoths (Lepidoptera: Sphingidae) collected in Grand Traverse and adjacent counties, Michigan}, journal = {Great Lakes Entomologist}, volume = {34}, year = {2001}, note = {Used Insects Collection.}, pages = {55-62}, abstract = {Thirty-two (32) species of hawkmoths (Sphingidae) are reported from Grand Traverse and adjacent counties, Michigan, based on collecting carried out in 1979-1997 and an inventory of museum records.}, keywords = {SPHINX}, author = {Douglass, Andrew W. and Douglass, Christopher B. and Douglass, John F.} } @article {70559, title = {Hematozoa of Hatch-year Common Mergansers from Michigan}, journal = {Journal of Wildlife Diseases}, volume = {37}, year = {2001}, pages = {403-407}, abstract = {Fifty-five hatch-year common mergansers (Mergus merganser) were sampled for hematozoa from Douglas Lake (Michigan, USA) on 17 July 1995. Forty-one (75\%) were infected with hematozoa. Haemoproteus greineri and Leucocytozoon simondi were common, infecting 28 (51\%) and 26 (47\%) common mergansers, respectively. Plasmodium circumflexum infected two (4\%) birds. The common merganser is a new host record for H. greineri and P. circumflexum. Intensity data indicate possible negative interspecific interaction between H. greineri and L. simondi.}, keywords = {PLASMODIUM}, author = {Dejong, Randall J. and Reimink, Ronald L. and Blankespoor, Harvey D.} } @article {70610, title = {Interactive effects of atmospheric CO2 and soil-N availability on fine roots of Populus tremuloides}, journal = {Ecological Applications}, volume = {10}, year = {2000}, note = {The first large chamber experiment, planted June 94 and harvested July-August 96.}, pages = {18-33}, abstract = {The objective of this experiment was to understand how atmospheric carbon dioxide (CO2) and soil-nitrogen (N) availability influence Populus tremuloides fine-root growth and morphology. Soil-N availability may limit the growth response of forests to elevated CO2 and interact with atmospheric CO2 to alter litter quality and ecosystem carbon (C) and N cycling. We established a CO2 X N factorial field experiment and grew six genotypes of P. tremuloides for 2.5 growing seasons in 20 large open-top chamber/root box experimental units at UMBS in northern lower Michigan (USA). In this paper we describe an integrated examination of how atmospheric CO2 and soil-N availability influence fine-root morphology, growth, mortality, and biomass. We also studied the relationship between root biomass and total soil respiration. Over 80\% of the absorbing root length of P. tremuloides was accounted for by roots <0.4 mm in diameter, and specific root length (100-250 m/g) was much greater than reports for other temperate and boreal deciduous trees. Elevated atmospheric CO2 increased the diameter and length of individual roots. In contrast, soil N had no effect on root morphology. Fine-root length production and mortality, measured with minirhizotrons, was controlled by the interaction between atmospheric CO2 and soil N. Rates of root production and mortality were significantly greater at elevated CO2 when trees grew in high-N soil, but there were no CO2 effects at low soil N. Fine-root biomass increased 137-194\% in high-N compared to low-N soil, and elevated atmospheric CO2 increased fine-root biomass (52\%) in high soil N, but differences in low soil N were not significant. Across all treatments, dynamic estimates of net fine-root production were highly correlated with fine-root biomass (soil cores; r=0.975). Mean rates of soil respiration were more than double in high-N compared to low-N soil, and elevated atmospheric CO2, when compared to ambient atmospheric CO2, increased mean rates of soil respiration 19\% in 1995 and 25\% in 1996. Across all treatments, total root biomass was linearly related to mean rates of soil respiration (r2=0.96). Our results indicate that atmospheric CO2 and soil-N availability strongly interact to influence P. tremuloides fine-root morphology, growth, and C turnover. Aspen-dominated ecosystems of the future are likely to have greater productivity fueled by greater nutrient uptake due to greater root length production. Further, it appears that elevated atmospheric CO2 will result in greater C inputs to soil through greater rates of fine-root production and turnover, especially in high-fertility soils. Increased C inputs to soil result in greater rates of soil respiration. At this time, it is not clear what effects increased rates of root turnover will have on C storage in the soil.}, keywords = {NUTRIENTS}, author = {Pregitzer, Kurt S. and Zak, Donald R. and Maziasz, Jennifer L. and DeForest, Jared L. and Curtis, Peter S. and Lussenhop, John} } @conference {70650, title = {Recent field results from the ERIM International M10 portable lidar}, booktitle = {Application of Lidar to Current Atmospheric Topics IIIProceedings of SPIE}, volume = {3757}, year = {1999}, pages = {67 - 78}, publisher = {SPIE}, organization = {SPIE}, address = {Denver, CO, USA}, abstract = {Wider use of lidar systems requires that they continue to become smaller, less expensive, and more reliable. To address this need, ERIM International has developed the M10 portable atmospheric lidar to measure aerosol profiles and cloud optical and physical properties. The system is based on a compact Nd:YAG laser and operates at either 532, 1064, or 1574 nm. The 1574 nm wavelength was added recently to address eye safety concerns. The system has been ruggedized for unattended field use and has been on several data collection campaigns recently. Date and analyses are presented from the Program for Regional Oxidants: Photochemistry, Emissions, and Transport Summer 1997 field study in Pellston, Michigan, and also from the Hyperspectral Day/Night Radiometry Assessment field study at Eglin AFB in Florida.}, keywords = {SENSOR DEVELOPMENT}, doi = {10.1117/12.366439}, author = {Fischer, Kenneth W. and Feak, Richard T. and Dinda, Bruce L.} } @booklet {70676, title = {Natural Danger Signals}, volume = {Winter 1998}, year = {1998}, note = {The magazine of Loyola University Chicago. Spotlights Dr. Nancy Tuchman working with her CO2 chambers on the hill.}, pages = {30-33}, keywords = {TYPHA}, author = {DeGrane, Susan} } @article {70720, title = {Captive-rearing piping plovers: developing techniques to augment wild populations}, journal = {Zoo Biology}, volume = {16}, year = {1997}, note = {Incubation was up in Pettingill, and rearing under the Cort porch.}, pages = {461-477}, abstract = {Techniques for captive-rearing and releasing piping plovers (Charadrius melodus) were developed using a surrogate species, killdeer (Charadrius vociferus). We compared captive- and parent-reared killdeer, and parent-reared piping plovers and determined that growth and behavior were similar. After surrogate trials determined that captive-rearing was feasible, we used the same methods to raise piping plover chicks from salvaged eggs. For captive-reared chick of both species, survival to fledging was higher than and behaviors similar to parent-reared chicks in the wild. Rearing techniques were fine-tuned, and ten piping plover fledgings were released to the wild. Based on our results, we developed recommendations for captive-rearing piping plovers using salvaged eggs to enhance productivity of small populations.}, keywords = {SURROGATE}, author = {Powell, Abby Neva and Cuthbert, Francesca Jean and Wemmer, Lauren Christine and Doolittle, Alice W. and Feirer, Shane T.} } @article {70722, title = {Dangers in dividing conservation biology and agroecology}, journal = {Conservation Biology}, volume = {11}, year = {1997}, pages = {1272-1273}, abstract = {With the hope of protecting biodiversity we must consider that one of our primary goals should be to reduce the level of degradation in managed areas, manage them appropriately, all the while entrusting to "nature" as much of the landscape as possible. To do this we need to address agricultural systems in terms of our research questions, funding priorities, and our influence on policy implementation, thus expanding the realm of conservation. Overcoming these challenges is not just a way to improve conservation biology--it is a necessity if we hope to reach our objectives. Without descending the ethical slippery slope concerning "naturalness," we can both encourage improved biodiversity protection on large portions of the managed landscape and at the same time oppose further degradation of remaining pristine areas.}, keywords = {HABITATS}, author = {Jules, Erik S. and Dietsch, Thomas V.} } @article {70710, title = {Effects of elevated atmospheric carbon dioxide on the growth and linear furanocoumarin content of celery}, journal = {Journal of Agricultural and Food Chemistry}, volume = {45}, year = {1997}, pages = {3642-3646}, abstract = {The effects of elevated atmospheric carbon dioxide on the growth and development of celery (Apium graveolens) were examined to determine if anticipated global increases in CO2 will affect the nutritional quality and secondary chemistry of celery. The size (fresh and dry mass), nitrogen and carbon composition, and concentrations of linear furanocoumarins of celery grown under ambient (363 uL/L) and elevated (718 uL/L) carbon dioxide were analyzed. Growth under elevated CO2 resulted in larger petioles, reduced nitrogen content, and higher C:N ratios in both leaves and petioles. However, CO2 treatment did not affect plant water content or carbon content. Moreover, in contrast to the carbon-nutrient balance hypothesis, the increased C:N ratios of plants grown under elevated CO2 were not associated with increased concentrations of potentially harmful linear furanocoumarins. Levels of linear furanocourmarins in the petioles of plants from each treatment did not exceed concentrations reported to cause acute or chron ic contact dermatitis.}, keywords = {SECONDARY}, author = {Reitz, S. R. and Karowe, David N. and Diawara, M. M. and Trumble, J. T.} } @article {70731, title = {Merlin (Falco columbarius) breeding record for Emmet Co., MI: further evidence and hypotheses for a range expansion}, journal = {Michigan Birds and Natural History}, volume = {4}, year = {1997}, pages = {193-196}, abstract = {In Michigan, Merlin (Falco columbarius) breeding records have come primarily from Isle Royale, with rare but regular reports from the Upper Peninsula (especially Keweenaw Co.). Breeding records for the lower Peninsula are even rarer: Michigan{\textquoteright}s breeding brid atlas project reported only one confirmed (Antrim Co.) and two probable (Alpena Co.) breeding records. Binford (1991) suggests that since 1980 the Merlin population may be increasing and expanding in both peninsulas as it recovers from declines (1946-1972) associated with organochlorine contaminant-induced reproductive failure. The purpose of this note is to report a new breeding record for Emmet Co. that supports this hypothesized expansion in the Lower Peninsula.}, keywords = {SIZE}, author = {Dietsch, Thomas V. and Cuthbert, Francesca Jean} } @article {70737, title = {Virginia Rail (Rallus limicola) predation on crayfish (Orconectes sp.) in a Lake Huron coastal wetland}, journal = {Michigan Birds and Natural History}, volume = {4}, year = {1997}, pages = {196-198}, abstract = {The Virginia Rail (Rallus limicola) is known to consume a wide range of prey including insects, snails, mollusks, and crustaceans. However, these reports come primarily from gizzard analysis and a captive bird study; little is known about the foraging behavior of this reclusive species in the wild. On 16 July 1997 the Biology of Birds class from UMBS watched a Virginia Rail as it captured and consumed a large crayfish (Orconectes sp.). The purpose of this note is to describe this rare observation.}, keywords = {RALLUS}, author = {Dietsch, Thomas V. and Cuthbert, Francesca Jean} } @proceedings {70776, title = {Whole Effluent Toxicity Testing: An Evaluation of Methods and Prediction of Receiving System Impacts}, journal = {Pellston Workshop on Whole Effluent Toxicity: 16-21 September 1995}, year = {1996}, note = {(eds.)}, pages = {340 pp.}, publisher = {Society of Environmental Toxicology and Chemistry (SETAC)}, address = {University of Michigan Biological Station, Pellston, MI}, abstract = {This book presents the proceedings of the 25th "Pellston Workshop," held September 16-21, 1995 at the University of Michigan Biological Station on Douglas Lake in Pellston, Michigan, where the workshop series began in 1977. Like previous workshops, participation was limited to invited experts from government, academia, and industry who were selected because of their experience with the workshop topic. The workshop provided a structured environment for the exchange of ideas and debate such that consensus positions would be derived and documented for some of the issues surrounding the science of whole effluenct toxicity testing and receiving system impact predictions. The proceedings reflect the current state-of-the-art of these topics and focus on an assessment of 1) the appropriateness of whole effluent toxicity endpoints used in routine WET methods, 2) the degree and causes of WET test method variability, 3) biotic and abiotic factors that can influence measured field responses to effluents, and 4) the relationship between effluent toxicity, ambient toxicity, and receiving system impacts.}, keywords = {WATER}, author = {Grothe, Donald R. and Dickson, Kenneth L. and Reed-Judkins, Donna K.} } @proceedings {70777, title = {Can captive rearing increase the endangered Great Lakes Piping Plover population?}, journal = {Restoration: Reality or Delusion, 57th Midwest Fish and Wildlife Conference}, year = {1995}, month = {December 5, 1995}, address = {Detroit, MI}, abstract = {Since placement on the Endangered Species List in 1986, the Great Lakes population of the Piping Plover (Charadrius melodus) has remained low with between 12 and 21 nesting pairs each year. Significant changes will need to occur in the reproductive output and/or survivorship of the Great Lakes Piping Plover if the U.S. Fish \& Wildlife Service Recovery Plan goal of 150 breeding pairs is to be met. To examine the effects of different recovery strategies on the Great Lakes population, I used a Pascal program which stochastically models population change through an annual time-step. I ran modeling experiments to examine population trends of the Great Lakes Piping Plover with no intervention and then with two different strategies of egg removal, artificial incubation, and captive rearing. In the first intervention strategy, entire clutches were removed from a portion of the nests with the expectation that some nesting pairs would renest after clutch removal. In the second strategy, single eggs were removed from a portion of the nests. Renesting was not expected for pairs with a single egg removed. Results indicate that both strategies of intervention have the potential to bring about greater increases in the breeding population than does the approach of no intervention. Entire-clutch removal has the potential to bring about a greater increases over a shorter period of time than does single-egg removal, but also resulted in more drastic population declines in more replicates of the model than did the single-egg removal strategy.}, keywords = {SIZE}, author = {Doolittle, Alice W.} } @mastersthesis {70799, title = {LIfe history characteristics and the landscape ecology of breeding birds in Michigan forests}, volume = {Master of Science}, year = {1995}, pages = {53 pp.}, school = {University of Michigan}, address = {Ann Arbor, MI}, abstract = {This study used a hierarchical landscape ecological classification produced by the UMBS landscape ecosystem mapping project in conjunction with protocols from the national Breeding Biology Research and Monitoring Database program to assess whether differences in the abundances of breeding birds in northern Michigan could be detected at two scales: landforms and local landscape ecosystems. In addition, nests were located and monitored to determine productivity and survivability. These productivity data were analyzed for spatial and temporal variation. I found that the relative abundances of birds, particularly neotropical migrants, exhibited more significant differences between landforms (i.e., an Outwash-upland landform [Upland], and an Outwash-lakeplain landform [Swamp]) than among the smaller local landscape ecosystems (e.g., Outwash-lake plain conifer-hardwood swamp: semi-permanently inundated). This suggests that relatively large landscape elements may be influencing the distributions of many breeding bird species more than smaller elements. Additionally, total species richness and warbler species richness were signficantly higher in the Swamp than in the Upland. Life history information is reported for several species of ground-nesting neotropical migrants. No differences in productivity were found among nesting substrates. The productivity of species (number of fledglings per nesting attempt) was significantly different between the two landorms and between 1994 and 1995. However, there was only one instance out of 20 successful nests of the partial brood mortality during the nestling period, which may result from starvation. Based on these latter two results and because a nest predator (i.e., Blue Jay) and a brood parasite (i.e., Brown-headed Cowbird) were more common in one landform than the other, this study suggests that predator-prey/host-parasite interactions may contribute more strongly to population dynamics than food availability for birds breeding in northern Michigan forests.}, keywords = {WARBLERS}, author = {Dietsch, Thomas V.} } @article {70801, title = {Neighbor relations within a community of epiphytic lichens and bryophytes}, journal = {The Bryologist}, volume = {98}, year = {1995}, pages = {29-37}, abstract = {The nearest neighbor relations of the cryptogams growing on Quercus rubra in Michigan were investigated over whole tree trunks, and over four subsections of trunks to partially eliminate the effects of microhabitat. At all scales numerous nonrandom associations were found, indicating that it is not only gross microhabitat requirements that determine these relationships. The associations were found to differ from place to place on the tree trunk. Despite sharing the same general habitat (the tree trunk), or part of the habitat (e.g., upper north side), some species and groups of species are rarely neighbors, whereas others are far more likely to coexist and therefore interact.}, keywords = {VASCULAR PLANTS}, author = {John, Elizabeth and Dale, Mark R. T.} } @article {70864, title = {Detecting the increased eutrophication rate of Douglas Lake, Michigan: the relative areal hypolimnetic oxygen deficit method}, journal = {Lake and Reservoir Management}, volume = {8}, year = {1993}, pages = {73-76}, abstract = {We use data gathered since 1971 on Douglas Lake, Michigan to illustrate the use of temperature and depth adjusted oxygen deficits to assess changes in the rate of lake eutrophication. The method of calculation with adjustments is presented. By comparing different hypolimnia in the multidepression lake, we show that localized lakeshore land use produces regional patterns of production that are detected by comparison of oxygen deficits. For some lake regions, the increase in oxygen deficit has had a linear doubling since 1971. Using historical data, this rate of change is much greater than for the previous 50 years. The oxygen deficits in the lake region farthest from lakeshore development averaged 60\% of those in the region nearest lakeshore development.}, keywords = {WATER CHEMISTRY}, author = {Lind, Owen T. and Davalos-Lind, Laura} } @article {70877, title = {Nest-site preference in male fathead minnows, Pimephales promelas}, journal = {Canadian Journal of Zoology}, volume = {71}, year = {1993}, pages = {1276-1279}, abstract = {Nest-site preference in fish is not often studied, and yet it should yield insight into their successful reproduction. I placed three sizes of artificial nest structures at three depths and two sides of a Michigan pond to investigate nest usage patterns by male fathead minnows. Of 93 artificial nest structures available, 18 were used as nests. Northern nest sites were used more than southern sites and structures of 100 and 200 cm2 were used more than those of 50 cm2. There was no differential use of structures between depths of 0.25 and 1 m. Other site preferences and alternative male mating strategies were also suggested.}, keywords = {SITE}, author = {DeWitt, Thomas J.} } @mastersthesis {70887, title = {Site characteristics and demography of Asplenium scolopendrium var. americana at two sites in Michigan}, volume = {Master of Science}, year = {1993}, pages = {48 pp.}, school = {University of Michigan}, address = {Ann Arbor, MI}, abstract = {Rare species are put at risk of extinction by our limited knowledge of them perhaps as much as by their limited numbers and habitat. The traditional management response has been passive and protective but it is becoming increasingly clear that preservation alone may be insufficient to safeguard many rare species. This study examined two populations of the threatened American hart{\textquoteright}s-tongue fern (Asplenium scolopendrium var. americana) growing on the Saint Ignace District of the Hiawatha National Forest in Michigan. Objectives of the study were to make inferences about the fern{\textquoteright}s ecology, to identify possible management strategies, and to make recommendations about further scientific study. Substantial variation in fern physical characteristics were documented both within and between the populations, with much of the variation attributable to micro-climate and canopy closure patterns. Demographic and geographic distributions further suggested that the fern{\textquoteright}s reproductive behavior may be a response to heat and moisture variations resulting from the disturbance regime of northern hardwoods forests. Future management practices recommended include blocking conifer invasion into the sites and placing rocks within the colonies to see if fern habitat can be maintained by introducing rocks to replace the original ones as they are covered by litter. Studies of rock chemistry, fern genetics, bryhophyte relationships, and localized perturbations are also suggested as avenues for further scientific inquiry.}, keywords = {VASCULAR PLANTS}, author = {Doherty, R. G.} } @article {70905, title = {Effects of nitrogen and phosphorus on the endosymbiont load of Rhopalodia gibba and Epithemia turgida (Bacillariophyceae)}, journal = {Journal of Phycology}, volume = {28}, year = {1992}, pages = {773-777}, abstract = {Diatoms of the family Epithemiaceae possess a unicellular nitrogen-fixing cyanobacterial endosymbiont. We investigated the potential of extracellular nitrogen and phosphorus concentrations to affect the endosymbiont load of Rhopalodia gibba O. Mull. and Epithemia turgida Ehr. in field and culture populations. In a growth chamber experiment, monoclonal cultures of R. gibba were exposed to three levels of nitrate-nitrogen. Nutrient-diffusing substrates were used in a lake environment to create nine microhabitats of varying nitrogen and phosphorus ratios for natural populations of R. gibba and E. turgida. The number of endosymbionts per diatom increased as ambient nitrogen became limiting; mean endosymbiont volume increased as nitrogen increased. The mean endosymbiont surface area: volume ration decreased with increasing nitrogen. Total endosymbiont volume per diatom (the product of the number of endosymbionts per diatom and their individual biovolumes) did not have a simple response to increasing nitrogen. Phosphorus limitation uncoupled the relationship between endosymbiont load and nitrogen. We suspect that flexibility of the endosymbiont load can reduce the metabolic cost to the diatom if the endosymbionts are dependent on the diatom for a resource.}, keywords = {SYMBIOSIS}, author = {DeYoe, Hudson R. and Lowe, Rex L. and Marks, Jane C.} } @article {70920, title = {Metabolic aspects of shivering thermogenesis in passerines during winter}, journal = {Ornis Scandinavica}, volume = {23}, year = {1992}, pages = {381-387}, keywords = {WINTER}, author = {Dawson, William R. and Carey, C. and Van{\textquoteright}t Hof, Thomas J.} } @article {70922, title = {Preliminary analysis of ERS-1 SAR for forest ecosystem studies}, journal = {IEEE Transactions on Geoscience and Remote Sensing}, volume = {30}, year = {1992}, pages = {203-211}, abstract = {In this paper we examine an image obtained by the C-band VV-polarized ERS-1 SAR with respect to potential land applications. A scene obtained near noon on Aug. 15, 1991 along the U.S.-Canadian border near Sault Ste. Marie is calibrated relative to an array of trihedral corner reflectors and active radar calibrators distributed across the swath. Extensive contemporaneous ground observations of forest stands are used to predict radar backscattering coefficients at the time of the SAR overpass using a first-order vector radiative transfer model (MIMICS). These predictions generally agree with the calibrated ERS-1 data to within 1 dB. It is demonstrated that the dynamic range of radar backscattering coefficient is sufficient to perform limited discrimination of various forest and grassland communities even for a single-date observation. Furthermore, it is demonstrated that retrieval of near-surface soil moisture is feasible for grass-covered soils when plant biomass is less than 1 tonne/ha.}, keywords = {VEGETATION}, author = {Dobson, M. Craig and Pierce, Leland and Sarabandi, Kamal and Ulaby, Fawwaz and Sharik, Terry L.} } @article {70929, title = {1991 CIESIN Project: Final report on sediment warming study and water quality lake survey. I. The effect of slightly elevated temperature on the benthic algal community of Douglas Lake, Michigan. II. A water quality survey of fifteen lakes in Cheboygan an}, year = {1991}, pages = {43 pp.}, institution = {University of Michigan Biological Station}, address = {Ann Arbor, MI}, abstract = {The objective of the study was to investigate the effects of a slight increase in temperature on the composition and biomass of the benthic algal community in a freshwater lake. The experimental design consisted on six ten-gallon aquaria that were continuously supplied with fresh lake water. Three of the tanks received lake water that was heated 3C while the other tanks received unheated lake water. Three baskets of lake sand were placed in each tank as algal substrates. At the end of the 28-day treatment period, the algae were separated from the sand and then enumerated and identified. There was no statistical difference in algal cell density, chlorophyll a concentration, or cell density of the dominant taxa between the treatments although there was a trend for higher algal biomass in the heated tanks. The heated and unheated tank communities were dominated by cyanobacteria and diatoms. Eight to sixteen algal taxa were unique to each community, but none were dominant. The Shannon-Weaver diversity indices were high (3.48-3.85) for both treatments and the lake community. The Horn{\textquoteright}s similarity index indicated that all the communities were similar. It was concluded that with an increase in replicates and a longer treatment period significant differences between the treatments might become apparent. The goal of this study was to collect water quality data on fifteen lakes included in the 1974 RANN study. The purpose was to provide recent water quality data for these lakes. The lakes were sampled three times during 1991: May 9-11, July 9-11 and October 5-7. Field measurements taken at the time of sample collection included depth, temperature, dissolved oxygen, pH, conductivity, Secchi disc depth, light penetration and color. Water samples collected from each lake at a depth of 2 m were analyzed for nitrate-nitrogen, ammonia-nitrogen, soluble reactive phosphate (SRP), total phosphate, dissolved silica, total alkalinity and turbidity. In addition, plankton samples were collected during each sampling trip and periphyton samples were collected from artificial substrates in July. Average pH values ranged from 7.1-8.3 except for the two bog lakes whose pH was approximately 4.5. Average total alkalinity values (2.2 to 149 mg CaCO3/L) and average conductivity values (25 to 321 uS/cm) were positively correlated. Average dissolved silica ranged from 0.10 to 6.6 mg SiO2/L and tended to increase from May to October. Mean total phosphate varied from 8.05 to 20.0 ug/L and were not highly correlated with average SRP (2.3 to 4.0 ug/L). No seasonal trend in phosphate levels was evident. Nitrate-nitrogen levels (range of means 3.8 to 43.4 ug/L) tended to be highest in May. The range of average ammonia-nitrogen concentrations was 0.08 to 1.73 mg/L and showed no seasonal trend. May phytoplankton biovolumes varied substantially and were lowest for nutrient-poor Cochran Lake and highest for mesotrophic Douglas Lake. A comparison of the cluster analyses of the 1974 and 1991 data suggested that the basic character of the lakes has not changed.}, keywords = {WATER CHEMISTRY}, author = {DeYoe, Hudson R. and Lowe, Rex L.} } @article {70930, title = {Beaconless search and rescue using airborne synthetic aperture radar}, year = {1991}, abstract = {This document summarizes work done during the last 36 months to determine the feasibility, methods and value of the use of special radar remote sensing techniques to detect and locate small downed aircraft hidden by forest environments. This subject will be referred to as beaconless search and rescue because it applies to distress situations where beacons either are not present or do not work. Although the methods described in the report apply airborne radar detection of a aircraft in forest environments, they would be even more successful when applied to aircraft downed in more open land areas, or vehicles, ships and aircraft in marine distress conditions. Also, satellite versions of the technique are possible and will be investigated after completion of the airborne radar investigation. The special radar referred to in this report is a synthetic aperture radar (SAR). This unique radar system has the unusual ability to produce images of great clarity from long distances and is also capable of remarkable target-to-clutter performance. Proper choice of radar wavelength also permits the penetration of vegetation canopies, including forests, which makes it an ideal candidate for the subject at hand. This report traces the efforts of the Goddard Space Flight Center Search and Rescue Office from the early recognition of SAR as a valuable tool through defining proof-of-concept field tests that firmly establish not only the efficacy of this technique, but the methods that yield its full value in realistic field conditions.}, keywords = {VEGETATION}, author = {Rais, Houra and McCandless Jr., Samuel W. and Mitchell, Pat M. and Dreibelbis, Roy R.} } @article {70952, title = {Pictured Rocks National Lakeshore survey of nesting birds: Beaver Rim Road Right-of-Way}, year = {1991}, note = {Pictured Rocks Nat. Lakeshore}, institution = {Prepared for Pictured Rocks National Lakeshore}, keywords = {NESTING}, author = {Dow, Douglas} } @mastersthesis {70958, title = {Specialization, foraging efficiency, and nutritional relationships in a solitary bee, Heriades carinata Cresson (Hymenoptera:Megachilidae)}, volume = {Master of Science}, year = {1991}, note = {4 sites all on our property.}, pages = {56 pp.}, school = {Michigan State University}, address = {East Lansing, MI}, abstract = {Pollen foraging preferences of Heriades carinata Cresson were investigated by trap nesting in field sites near Pellston, Michigan during the summers of 1988 and 1990. During the peak of the nesting season, females of H. carinata provisioned exclusively with pollen from Rhus typhina L. (Anacardiaceae). The flight season of H. carinata was synchronized with the flowering of Rhus, and nesting activity by H. carainata was only found in study sites containing Rhus. H. carinata is at least regionally specialized on Rhus and may be oligolectic on this plant genus. Timed flights of H. carinata females foraging for Rhus pollen were not different from those foraging from other plants. Survival by offspring of H. carinata to adulthood was higher on provisions consisting of Rhus pollen than on other pollens.}, keywords = {SUMAC}, author = {DeNike, Jonathon Michael} } @article {70972, title = {Ambient concentrations, scavenging ratios, and source regions of acid related compounds and trace metals during winter in northern Michigan}, journal = {Atmospheric Environment}, volume = {24A}, year = {1990}, pages = {2981-2989}, keywords = {WET DEPOSITION}, author = {Cadle, Steven H. and Vande Kopple, Robert J. and Mulawa, Patricia A. and Dasch, Jean Muhlbaier} } @article {70982, title = {Diurnal patterns of the bi-directional reflectance of fresh-water ice}, journal = {Annals of Glaciology}, volume = {14}, year = {1990}, pages = {153-157}, abstract = {To improve the imterpretation of surface cryospheric albedo from satellite sensor data, diurnal measurements of the spectral bi-directional reflectance of a commonly-found fresh-water ice type were made, from which hemispherical reflectance can be derived. The purpose of this study is to document its clear-sky, bi-directional reflectance characteristics in the visible (650-670 nm) and near-infrared (810-840 nm) region, assess the diurnal nature of the reflectance, and quantify the surface anisotropy. Bi-directional reflectances of the re-frozen slush ice measured show a spectral dependence and change significantly with solzr zenith angle. Considerable variation occurs at each view angle and among view angles throughout the day. Although diurnal reflectance patterns were similar in both bands, magnitudes varied greatly, being highest in the visible and lowest in the near-infrared region. With the exception of peak saturated (specular) values in the forward scatter direction, bi-directional reflectance was generally highest in the morning when the surface and the illumination were most diffuse in character. The exitance computed from nadir radiance (N) is compared to the measured hemispheric exitance (M). The exitance/measured hemispheric exitance ratios, an index of anisotropy, reveal an anisotropy that increases with increasing solar zenith angle and is more pronounced in the near-infrared region.}, keywords = {SOLAR}, author = {Leshkevich, George A. and Ahmad, Suraiya P. and Eck, Thomas F. and Deering, Donald W.} } @inbook {71012, title = {Terrestrial Gastropoda}, booktitle = {Soil Biology Guide}, year = {1990}, pages = {201-309}, publisher = {John Wiley \& Sons, Inc.}, organization = {John Wiley \& Sons, Inc.}, address = {New York, NY}, keywords = {TERRESTRIAL}, author = {Burch, John B. and Pearce, Timothy Allen}, editor = {Dindal, Daniel L.} } @article {71042, title = {Repeatability of invasion of eastern white pine on dry sites in northern lower Michigan}, journal = {The American Midlands Naturalist}, volume = {122}, year = {1989}, pages = {133-141}, abstract = {Age-specific densities of eastern white pine (Pinus strobus) were determined in a series of forest stands in northern lower Michigan, originating 73, 48, 36, 30 and 4 yr prior to the present study, following prescribed logging and burning. These data were used to reconstruct the invasion patterns of eastern white pine and to make inferences about the repeatability of community change following disturbance. Initial invasion of white pine was more rapid in stands of recent origin (1 and 4 yr after the disturbance for the 36- and 30-yr-old stands, respectively, vs. 15 and 25 yr after the disturbance for the 48- and 73-yr-old stands, respectively). In contrast, white pine population growth reached an asymptote more quickly in stands of recent origin compared to older stands. There was little recruitment of white pines in any of the stands since the early 1970s. Thus, we rejected the hypothesis that community change proceeds similarly in all stands, independent of their time of origin. Our results suggest that the substantial stochastic component in colonization and subsequent increase of populations of potentially dominant forest trees during secondary succession may be affected by different autogenic and allogenic factors.}, keywords = {TERRESTRIAL}, author = {Sharik, Terry L. and Ford, Robert H. and Davis, Martha L.} } @mastersthesis {71043, title = {Response of an algal community to temporal variability of resources}, volume = {Master of Science}, year = {1989}, pages = {62 pp.}, school = {Bowling Green State University}, address = {Bowling Green, OH}, abstract = {Competition has been one of the most widely debated theories in ecology. In particular, the role of natural environmental variability has been contested. This project was designed to test for the effect of temporal variability in resources on a natural algal community. The study was carried out on the E. Branch of the Maple River near Pellston, Michigan. Twenty four artificial channels were constructed and dosed with both nitrogen and phosphorus. Nutrients were supplied in two concentrations, one with high nitrogen and one with low. The nitrogen levels were switched at intervals of 12, 24, 48 and 96 hours to produce temporal variability. Artificial substrata were collected and enumerated for taxa of live algae. There were no significant responses to nutrient addition. It was impossible to discriminate between unenriched controls and the nutrient enhanced streams both at the community level and with individual taxa. All channels showed a significant accumulation of flocculent material through the 16 day experiment. This silty material was highly correlated with algal biovolume. It was impossible to determine whether this correlation was due to the physical process of passive accumulation or a biological response to the silty material.}, keywords = {WATER CHEMISTRY}, author = {Deutschman, Douglas H.} } @article {71052, title = {What{\textquoteright}s special about the physiological ecology of desert organisms?}, journal = {Journal of Arid Environments}, volume = {17}, year = {1989}, abstract = {The Physiological Ecology Section of the International Workshop {\textquoteright}What{\textquoteright}s Special about Desert Ecology?{\textquoteright} was organized to allow examination of the thematic question through prespectives provided by work on a diverse array of desert organisms. The convenors are mindful that desert plants and invertebrates merit far more attention that could be devoted to them in the time available. However, even with the bias toward vertebrates, the material presented by the five speakers ranged sufficiently to provide an overview of prominent adaptive patterns of plants and animals to deserts, and some introduction to the relevant literature. J. A. Teeri provided the account of Crassulacean acid metabolism in plants and M. K. Seely that on desert invertebrates. V. H. Shoemaker, G. A. Bartholomew, and A. Shkolnik contributed the segments of this synopsis dealing with ectothermic vertebrates, endothermic vertebrates and desert ungulates, respectively.}, keywords = {VASCULAR PLANTS}, author = {Dawson, William R. and Pinshow, Berry and Bartholomew, George A. and Seely, Mary K. and Shkolnik, Amiram and Shoemaker, Vaughan H. and Teeri, James A.} } @article {71095, title = {Wintertime concentrations and sinks of atmospheric particulate carbon at a rural location in northern Michigan}, journal = {Atmospheric Environment}, volume = {22}, year = {1988}, pages = {1373-1381}, abstract = {Particulate elemental carbon, organic carbon, and SO4-2 wintertime atmospheric concentrations were determined at a rural site in northern Michigan during two winters. Examination of the concentrations, based on both surface-wind direction and backward-trajectory analysis, indicated that concentrations were significantly influenced by the long-range transport of pollutants. Measurements of the wet- and dry- deposition rates of elemental carbon showed that it is removed primarily by wet deposition at this site. The dry deposition velocity of elemental carbon to a snow surface averaged < 0.2 cm/s during most of the study, but was considerably higher for one period during which it appeared to be influenced by large particles from local sources. A comparison of the scavenging ratios of SO4-2 and elemental carbon shows that snow removes SO4-2 at least twice as efficiently as elemental carbon. This difference implies that the atmospheric residence time of elemental carbon in the winter will be considerably longer that that of SO4-2, if precipitation occurs. In the absence of precipitation, the estimated residence time of elemental carbon is at least 6 days. These results suggest that elemental carbon can be transported long distances and, thus, may degrade visibility and have other effects over wide regions.}, keywords = {WINTER}, author = {Cadle, Steven H. and Dasch, Jean Muhlbaier} } @article {71102, title = {Composition of snowmelt and runoff in northern Michigan}, journal = {Environmental Science and Technology}, volume = {21}, year = {1987}, pages = {295-299}, abstract = {Snowmelt and runoff were studied during the 1982-1983 and the 1983-1984 winters at the University of Michigan Biological Station, which is located near the northern tip of Michigan{\textquoteright}s lower peninsula. The first 50\% of the snowpack acidity was released in meltwater and rainwater equal to 25\% of the original snowpack water content. Interaction between the meltwater and the litter layer produced large changes in the concentrations of most species. Runoff to two streams had high SO4-2 and very low NO3- concentrations. It is concluded that most of the NO3- is either biologically utilized or retained in the watershed, even during the early snowmelt period at this site.}, keywords = {WET DEPOSITION}, author = {Cadle, Steven H. and Dasch, Jean Muhlbaier and Vande Kopple, Robert J.} } @inbook {71104, title = {The contribution of dry deposition to snowpack acidity in Michigan}, booktitle = {Seasonal Snowcovers: Physics, Chemistry, Hydrology}, year = {1987}, pages = {299-320 of 746}, publisher = {D. Reidel Publishing Company}, organization = {D. Reidel Publishing Company}, address = {Boston, MA}, abstract = {Wet deposition, dry deposition, and snowpack chemistry were studied during two winters at a rural location in northern Michigan and during one winter at an urban location in sourthern Michigan. The dry deposition rates were determined by measuring concentration changes in exposed snow samples. Dry deposition velocities were calculated from multi-day measurements of both the deposition rate and the atmospheric concentration of the depositing species. The average deposition velocities of HNO3, SO2, NH4+, and Ca+2 were 1.1, 0.09, 0.09, and 2.0 cm/s, respectively. HNO3 was the dominant source of the dry deposited NO3-, while SO2 was the dominant source of the dry deposited SO4-2. Good agreement was found between the cumulative wet and dry deposition of most species and the snowpack content before the first melt period. Comparisons between wet and dry deposition showed that dry deposition contributed only 6 and 11\% of the total acidity deposited at the rural and urban locations, respectively. The dry deposition contribution for species other than H+ ranged from 14 to 80\%. The greatest dry deposition contributions for all species were at the urban site. It is concluded that dry deposition has a large impact on the snowpack content of some species, but little net effect on the acidity.}, keywords = {WET DEPOSITION}, author = {Cadle, Steven H. and Dasch, Jean Muhlbaier}, editor = {Jones, H. G. and Orville-Thomas, W. J.} } @article {71146, title = {Effects of Lake Michigan water levels on wetland soil chemistry and distribution of plants in the Straits of Mackinac}, journal = {Journal of Great Lakes Research}, volume = {12}, year = {1986}, pages = {175-183}, abstract = {The effects of short-term or summer season water level fluctuations on wetlands were determined from measurements of flooding, relative soil chemistry, and the presence of plants. Analyses demonstrated higher relative concentrations of plant-available soil nutrients and higher density of plants on flooded emergent wetlands as compared to infrequently flooded, unconsolidated shore sites. Flooding resulted in anaerobic soil conditions and increased concentrations of nutrients for wetland plants. The density of emergent wetland plants was highest where the topographic conditions and water level led to duration of flooding between 50 and 85\% of the growing season. The effects of long-term water level fluctuations on wetlands were measured from historical aerial photographs of low, average, and high lake level conditions (1938 to 1980). An increase in water levels of 0.3 m reduced the extent of coastal wetlands by 18\%. Historical aerial photos demonstrated and a model predicted that 13\% of the total wetlands measured at low lake levels remained in the study area at the highest lake level sampled. This result was verified during the high lake levels of May 1985.}, keywords = {WETLANDS}, author = {Lyon, John Grimson and Drobney, Ronald D. and Olson Jr., Charles E.} } @mastersthesis {71181, title = {Use of aerial photographs to predict lake selection and reproductive success of Common Loons in Michigan}, volume = {Master of Science}, year = {1986}, pages = {41 pp.}, school = {University of Michigan}, address = {Ann Arbor, MI}, abstract = {The purpose of this study was to identify key components of an environment whose relationship and interactions can collectively predict, from a random sample of lakes, which will be used by common loons for nesting, and which of those used will be more apt to support a loon pair that will successfully fledge young. Variables evaluated include physical parameters of each lake, human use factors, and nest site characteristics. Of these variables, those that can be remotely sensed from aerial photographs were determined. A probit analysis identifed lake circumference and the presence or absence of a nesting platform offshore as being the best combination of variables to predict lake use. Of 63 lakes, 74.6\% were predicted correctly as to whether or not they were used by loons for nesting. Larger lakes with islands, bog mats, or hummocks for nesting were used more readily by loons. Lake area and the percent developed shoreline were the two variables that proved most useful in predicting if a pair of loons on a lake would successfully fledge young. Of the 25 lakes used by loons, 72.0\% were correctly classified as successful or not. Lakes with larger surface areas and a smaller percent of their shoreline covered by homes, campsites and beaches harbored loons that were more successful at fledging young. All four variables mentioned above can be quantified remotely from aerial photographs. The use of aerial photographs and other remotely sensed data provides an accurate medium for resource evaluation which can substantially decrease expenses by minimizing the amount of cost-intensive field work.}, keywords = {REPRODUCTIVE SUCCESS}, author = {Dahmer, Paul Andrew} } @article {71182, title = {Wintertime wet and dry deposition in northern Michigan}, journal = {Atmospheric Environment}, volume = {20}, year = {1986}, pages = {1171-1178}, abstract = {Wet and dry deposition were monitored at the University of Michigan Biological Station in rural northern Michigan for three winters. Dry deposition was measured by both the conventional bucket methods and by measuring increases in concentration in exposed, elevated snow samples. Average results of the two methods were in reasonable agreement. The cumulative wet and dry deposition quantities are in good agreement with snowpack accumulations until the first thaw period. Dry deposition to snow accounts for less than 15\% of the total H+, SO4-2, NO3-, and NH4+ and approximately 25\% of the Ca+2, Mg+2, Na+, K+ and Cl- during an average precipitation year. Snowpack measurements were also made under deciduous and red pine canopies. Decreases in H+ and NO3- were observed under the red pine canopy.}, keywords = {WET DEPOSITION}, author = {Cadle, Steven H. and Dasch, Jean Muhlbaier and Vande Kopple, Robert J.} } @article {71192, title = {Atmospheric concentrations and the deposition velocity to snow of nitric acid, sulfur dioxide and various particulate species}, journal = {Atmospheric Environment}, volume = {19}, year = {1985}, pages = {1819-1827}, abstract = {A study of deposition velocities to snow was conducted during the 1982-83 and 1983-84 winters at the University of Michigan Biological Station in northern Michigan. Weekly measurements were made of dry deposition rates to snow and the atmospheric concentrations of the deposition species. SO2, with an average concentration of 2.2 ppb, was the dominant atmospheric sulfur containing species. NO2, with an average concentration of 1.8 ppb, was the dominant atmospheric nitrogenous species. NO3- deposition was due primarily to HNO3, which averaged 0.2 ppb. The HNO3 deposition velocity averaged 1.4 cm/s. The SO2 depsoition velocity varied with temperature, averaging 0.15 cm/s for samples with appreciable exposure time above -3C, and 0.06 cm/s for samples which remained below an ambient temperature of -3C. Deposition velocities of Ca+2, Mg+2, Na+, K+ and NH4+ were 2.1, 1.5, 0.44, 0.51 and 0.10 cm/s, respectively. The mass median diameters of these species were 4.4, 2.7, 1.8, 0.9 and 0.46 um, respectively.}, keywords = {VELOCITY}, author = {Cadle, Steven H. and Dasch, Jean Muhlbaier and Mulawa, Patricia A.} } @inbook {71245, title = {Aquatic Coleoptera}, booktitle = {An Introduction to the Aquatic Insects of North America, pp. .}, year = {1984}, pages = {361-437}, publisher = {Kendall/Hunt Publishing}, organization = {Kendall/Hunt Publishing}, keywords = {INSECTS}, author = {White, David S. and Doyen, J. T. and Brigham, W. U.}, editor = {Merritt, R. W. and Cummins, K. W.} } @article {71249, title = {Comparative spermatogenesis in the Jungermanniales (Hepaticae) I. Observations on the structure of the young spermatids of Cephalozia lunulifolia and Chiloscyphus pallescens}, journal = {Journal of Bryology}, volume = {13}, year = {1984}, pages = {247-256}, abstract = {A comparative analysis of the young spermatids of Cephalozia and Chiloscyphus reveals the organization of the Jungermannialian blepharoplast to be basically the same as in other hepatics and mosses. Common features include the four-layered multilayered structure, the spatulate, asymmetrical anterior portion of the spline, and the staggered subapical insertion of the basal bodies, each with proximal triplet extensions. The range of spline widths in the Jungermanniales appears to be as great as in other groups of bryophytes and of no major taxonomic significance, but the position of the spline aperture may be more variable in hapatics than mosses. The lengths of the basal bodies are intermediate between those from unrelated taxa in other orders of hepatics. However, the data also suggest the Jungermannialian spermatids exhibit many taxonomic variations and novel features. Whereas the left-lateral expansion of the spline in Cephalozia is common to most other bryophytes, a right-lateral expansion is peculiar to Marsupella. Chiloscyphus manifests an intermediate condition: its spline is unequally bilateral, the left-lateral expansion wider than the right. Lateral extensions of the lamellar strip beyond the spline in Cephalozia, Chiloscyphus and Marsupella have been previously recorded only in Anthocerotae. A posterior notch on the right hand side of the lamellar strip in Marchantiales is absent in Chiloscyphus and Cephalozia and has not been observed in the Metzgeriales.}, keywords = {SPERMATIDS}, author = {Rushing, Ann E. and Carothers, Zane B. and Duckett, Jeffrey G.} } @article {71270, title = {Lake level effects as measured from aerial photos}, journal = {Journal of Survey Engineering}, volume = {110}, year = {1984}, abstract = {Rising Lake Michigan water levels were found to negatively influence the amount of wetlands and beaches in the Straits of Mackinac area of Lake Michigan. The effects of long-term fluctuation in water levels were determined from measurements of wetlands and beaches on seven sets of historical aerial photographs (1938-1980). Analysis of aerial photographs demonstrated a 380 acre (154 ha) difference in total wetland and beach areas at the highest lake level sampled, as compared to the total at the lowest lake level sampled, or a range of 4 ft (1.2m). A linear model between total wetland and beach areas and water levels (R2 = 0.93) indicated an increase of 1 ft (0.3m) would result in a decrease of 80 acre (32 ha) or 18\% of the 439 acre (178 ha) of wetlands and beaches in the study area. This methodology, which includes measurements from historical aerial photographs, acquisition of small format aerial photographs, and determination of local hydrological conditions, was useful for quantifying change in these lacustrine wetlands.}, keywords = {WETLANDS}, author = {Lyon, John Grimson and Drobney, Ronald D.} } @article {71278, title = {Northern Michigan snowpack-a study of acid stability and release}, journal = {Atmospheric Environment}, volume = {18}, year = {1984}, pages = {807-816}, abstract = {Weekly samples of wet deposition, dry deposition, and the snowpack were collected during the 1981-1982 winter at the University of Michigan Biological Station which is located near Pellston, Michigan. All the major acidic and basic species were determined. Comparison of the cumulative wet deposition acid loading to the snowpack loading as well as an examination of concentration vs. depth profiles showed that all species were stable in the snowpack until the spring thaw period. During the spring thaw, approximately 50\% of the acids were contained in the first 20\% of the snowmelt. Rainfall during the thaw period deposited as much nitrate and acid and more than double the amount of sulfate as was released from the snowpack. It was also concluded that dry deposition to snow at this location was not significant.}, keywords = {WET DEPOSITION}, author = {Cadle, Steven H. and Dasch, Jean Muhlbaier and Grossnickle, Nevin E.} } @article {71286, title = {Retention and release of chemical species by a northern Michigan snowpack}, journal = {Water, Air, and Soil Pollution}, volume = {22}, year = {1984}, pages = {303-319}, abstract = {Snowcore and water samples were collected during the 1981 to 82 winter at two independent sites in Northern Michigan; the Little Pigeon River and McNearney Lake. Acidic and basic species were determined in all samples. Examination of the concentration vs depth profiles of snow cores showed that all species were stable in the snowpack until the spring thaw period. During the thaw, 50 to 70\% of the stored acids were released during the first 20\% of the snowmelt. However, rainfall during the melt period contributed as much acidity to the environment as the snowmelt. Study of runoff showed that only 30\% of the nitrate originally present in the snowpack appeared in the Little Pigeon River. Therefore, H2SO4 dominated the runoff acidity at the Little Pigeon River. Both nitrate and sulfate were responsible for the slight acidification of McNearney Lake during the snowmelt period.}, keywords = {WET DEPOSITION}, author = {Cadle, Steven H. and Dasch, Jean Muhlbaier and Grossnickle, Nevin E.} } @inbook {71333, title = {The relationship of freshwater protozoan communities to the MacArthur-Wilson equilibrium model}, booktitle = {Diversity Hutchinson}, year = {1983}, pages = {272-287}, publisher = {Ross Publishing Company}, organization = {Ross Publishing Company}, address = {Stroudsburg, PA}, keywords = {PROTOZOA}, author = {Cairns Jr., John and Dahlberg, M. L. and Dickson, Kenneth L. and Smith, Nancy and Waller, William T.}, editor = {Patrick, R.} } @proceedings {71367, title = {Modeling the Fate of Chemicals in the Aquatic Environment}, journal = {The Fourth Pellston Environmental Workshop}, year = {1982}, note = {(eds.)}, pages = {ix + 413}, publisher = {Ann Arbor Science Publishers}, keywords = {MODELING}, author = {Dickson, Kenneth L. and Maki, Alan W. and Cairns Jr., John} } @article {71386, title = {Thirteen-fold change in population size of Peromyscus leucopus}, journal = {Canadian Journal of Zoology}, volume = {60}, year = {1982}, pages = {2224-2225}, abstract = {A live-trapping study of a population of white-footed mice Peromyscus leucopus was carried out during the midsummers of 1976, 1977, 1979, and 1981. The trapping grid (60 x 120m) was located in a lakeside forest in the northern portion of the lower peninsula of Michigan, U.S.A. Extremes in estimated population size were 11 individuals in 1979 and 139 in 1981.}, keywords = {SIZE}, author = {Sexton, Owen J. and Pesce, Andrea and Bloye, Robert R. and Douglass, John F.} } @book {71434, title = {Biotransformation and Fate of Chemicals in the Aquatic Environment}, year = {1980}, note = {(eds.)}, publisher = {The American Society For Microbiology Press}, organization = {The American Society For Microbiology Press}, address = {Washington, D.C.}, abstract = {To fully understand the contents of this book and the workshop from which it emanates, a review of activities which influenced the contents is helpful. The Toxic Substances Control Act (TSCA) was passed by Congress in October 1976, stipulating that no person may manufacture or process a chemical substance for a new use without obtaining clearance from the U. S. Environmental Protection Agency. TSCA represents an attempt to establish a mechanism whereby the hazard of a chemical substance to human health and the environment can be assessed before the chemical is introduced into the environment. In an effort to assist in the development of this conceptual framework for conducting an evaluation of the hazard of chemicals to aquatic life, an ad hoc workshop was conducted on 13-17 June 1977 at the University of Michigan{\textquoteright}s Biological Station, Pellston, Mich., entitled "Application of Toxicity Testing Methods as Predictive Tools for Aquatic Safety Evaluation." The 1977 Pellston workshop and the 1978 Waterville Valley workshop were extremely useful in addressing state-of-the-art testing methods and hazard evaluation schemes. Both indicated the considerable effort was needed in the development of methods to predict the environmental fate of chemicals. For this reason, a thrid workshop was planned, organized, and conducted around the theme "Biotransformation and Fate of Chemicals in th eAquatic Environment." This workshop was held on 14-18 August 1979 at the University of Michigan{\textquoteright}s Biological Station in Pellston; it focused on the methodology for biodegradation testing of chemicals and considered how predictive modeling contributes to fate determinations. The proceedings of this workshop constitute the contents of this book.}, keywords = {TOXICANTS}, author = {Maki, Alan W. and Cairns Jr., John and Dickson, Kenneth L.} } @article {71437, title = {The development and calibration of a spatially simplified multi-class phytoplankton model for Saginaw Bay, Lake Huron}, year = {1980}, pages = {126 pp}, institution = {Great Lakes Basin Commission}, address = {Ann Arbor, MI}, abstract = {A multi-class, internal nutrient pool, phytoplankton simulation model was developed and applied to an extensive set of field data acquired in 1974 on Saginaw Bay, Lake Huron. Phytoplankton biomass was partitioned into five functional groups: diatoms, greens, heterocystous blue-greens, non-heterocystous blue-greens, and "others". The nutrients included in the model were phosphorus, nitrogen, and silicon. The model was applied to a single spatial segment encompassing the inner portion of Saginaw Bay.}, keywords = {WATER}, author = {Bierman Jr., V. J. and Dolan, D. M. and Stoermer, Eugene F. and Gannon, John Edward and Smith, V. E.} } @inbook {71462, title = {Physiological and ecological aspects of the cosmopolitan Opilionid, Phalangium opilio}, booktitle = {Soil biology as related to land use practices: proceedings of the VII International Soil Zoology Colloquium of the International Society of Soil Science (ISSS), Syracuse, 29 July-3 August 1979}, year = {1980}, publisher = {Office of Pesticide and Toxic Substance, Environmental Protection Agency}, organization = {Office of Pesticide and Toxic Substance, Environmental Protection Agency}, address = {Washington, D. C.}, keywords = {SPIDERS}, author = {Edgar, Arlan Lee}, editor = {Dindal, Daniel L.} } @conference {71476, title = {Analyzing the Hazard Evaluation Process}, booktitle = {International Workshop on the Application of Hazard Evaluation Programs for Chemicals in the Aquatic Environment}, year = {1979}, note = {(eds.)}, publisher = {American Fisheries Society}, organization = {American Fisheries Society}, address = {Waterville Valley, N.H}, abstract = {The chemical industry has experienced rapidly expanding growth over the last 75 years to the point where there are now approximately 2 million recognized chemical compounds and derivatives in existence with almost 250,000 new compounds synthesized each year. While providing numerous societal benefits, modern chemical technology has also brought about a marked increase in the number and variety of chemical pollutants ultimately entering natural surface waters. Recent estimates from the United States Environmental Protection Agency indicate that although the majority of these new compounds will not be commercialized, nearly 1,000 new chemicals annually have the potential for environmental release as a result of marketing, use, and disposal. As our understanding of the structure and functioning of the aquatic environment has grown, it has become obvious that the capacity of our rivers, lakes, and oceans to assimilate chemical wastes and toxic materials discharged into them is not at all infinite and that serious degradation of water quality is the inevitable result of misuse and mismanagement of this invaluable resource.}, keywords = {TOXINS}, author = {Dickson, Kenneth L. and Maki, Alan W. and Cairns Jr., John} } @article {71482, title = {Desiccation in the Black Dragon, Hagenius brevistylus Selys}, journal = {Experientia}, volume = {35}, year = {1979}, pages = {751-752}, abstract = {Hagenius brevistylus lost mass by evaporation in a moderately desiccating environment at the rate of 20.4 mg/h, and died of desiccation in less than 1 day at a body mass of 79.8\% of their normally hydrated mass. It was estimated that Hagenius minimally would have to consume the equivalent of 60\% of its body mass each day to meet its daily water requirements. This amount of food is equivalent to that necessary to power flight of a dragonfly for 4.6 h.}, keywords = {WATER LOSSES}, author = {Tracy, Barbara Jean and Tracy, C. Richard and Dobkin, David S.} } @article {71506, title = {The role of posturing in behavioral thermoregulation by black dragons (Hagenius brevistylus Selys; Odonata)}, journal = {Physiological Zoology}, volume = {52}, year = {1979}, pages = {565-571}, abstract = {The effectiveness of thermoregulatory postures in the black dragon (Hagenius brevistylus Selys; Odonata) was tested relative to wind speed and air temperature on live and dead dragonflies in a closed circuit wind tunnel. The postures appeared to allow the dragonflies to behaviorally select body temperatures exceeding a range of 20 C and reach temperatures as low as the ambient air or as high as the sun-warmed substrate. At least one posture appeared to be transitory and appeared to be used primarily to warm up from low body temperatures. Live dragonflies kept individually in a large flight cage showed different patterns of posturing depending on the amount of insolation. Free-ranging dragonflies were not active at low air temperatures, and postured differently in response to different substrate temperatures. We concluded that black dragons can select from a broad range of potential body temperatures as the result of behavioral posturing.}, keywords = {TEMPERATURE}, author = {Tracy, C. Richard and Tracy, Barbara Jean and Dobkin, David S.} } @book {71535, title = {Estimating the Hazard of Chemical Substances to Aquatic Life}, volume = {Spec. Tech. Publ. 657}, year = {1978}, note = {(eds.)}, pages = {278}, publisher = {American Society for Testing and Materials (ASTM)}, organization = {American Society for Testing and Materials (ASTM)}, abstract = {The science of aquatic toxicology is presently in an embryonic, although rapidly evolving, state. The vast majority of testing procedures and protocols now being used to assess the effects of chemical substances on the survival, growth, and reproduction of representative aquatic species were virtually unknown as recently as 10 years ago. The associated risks to aquatic life are being increasingly considered in marketing decisions along with the societal benefits gained from the ultimate use of new chemical substances.}, keywords = {TOXINS}, author = {Cairns Jr., John and Dickson, Kenneth L. and Maki, Alan W.} } @article {71582, title = {Effects of intermittent chlorination on aquatic organisms and communities}, journal = {Journal of Water Pollution Control Federation}, volume = {49}, year = {1977}, pages = {35-44}, abstract = {It was the objective of the studies reported in this paper to identify the effects that frequency of exposure, concentration and form of chlorine, and duration of exposure had on the expression of fish mortality, and to evaluate the effects of intermittent chlorination on protozoan community structure.}, keywords = {STRUCTURE}, author = {Dickson, Kenneth L. and Cairns Jr., John and Gregg, Benjamin C. and Messenger, David I. and Plafkin, James L. and van der Schalie, William Henry} } @article {71584, title = {Environmental variables affecting small-scale distributions of five rotifer species in Lancaster Lake, Michigan}, journal = {Internationale Revue der Gesamten Hydrobiologie}, volume = {62}, year = {1977}, pages = {511-521}, abstract = {The small-scale distributions of the rotifers Polyarthra vulgaris, Synchaeta stylata, Conochilus unicornis, Hexarthra mira, and Asplanchna priodonta were investigated in Lancaster Lake, Cheboygan County, Michigan, July 21, 1974. Measurements were taken for 13 depths (at 1-m intervals) and at 4 times of the day (1:00 AM, 7:00 AM, 1:00 PM, and 7:00 PM). In addition, the abundances of 6 crustacean, 2 planktonic dipteran, and 10 algal species, as well as temperature, light, oxygen, chlorophyll a, alkalinity, pH and free carbon dioxide were measured. Whereas abiotic factors appeared to control large scale occupation of the lake, and excluded most species from the deeper portions of the hypolimnion, small-scale distributional variation of the rotifers depended upon biotic interactions, particularly with the crustacean zooplankton.}, keywords = {ZOOPLANKTON}, author = {Fairchild, George Winfield and Stemberger, Richard S. and Epskamp, Lawrence C. and Debaugh, Henry A.} } @article {71635, title = {Metabolism and thermoregulation in hatchling Ring-billed gulls}, journal = {The Condor}, volume = {78}, year = {1976}, pages = {49-60}, abstract = {Thermoregulatory capacities of young Ring-billed Gulls (Larus delawarensis) were studied within the first 24 hr after hatching. These birds controlled body temperatures (Tb) effectively over 2-hr tests conducted at single ambient temperatures (Ta) baetween 20 and 45.6 deg. C. Increasing heat production constitutes an important element in this control between 20 and approximately 34 deg. C. Metabolic rates of hatchlings at the lower temperature were approximately double those at the higher, where minimal rates for euthermic birds occurred. Electromyographic observations indicated that shivering contributes importantly to increasing heat production. The chicks also possess some capacities for controlling insulation. They additionally displayed a well-devloped panting response at high Ta{\textquoteright}s, which contributed to effective evaporative cooling. Below 20 deg. C., Tb varied directly with Ta at the end of 2-hr tests, but the birds remained at least 5 deg. C warmer than their surroundings even when exposed to 10 deg. C. The chicks tolerated hypothermia. Field observations indicated that hatchling Ring-billed Gulls in the absence of their parents can be exposed to either heat or cold stress on June days, depending on whether they are in the sun or shade. Comparisons of the thermoregulatory capacities of hatchling Ring-billed Gulls with those of hatchlings of other species are presented. Among gulls, some interspecific variation seems to exist in the thermogenic capacities of the chicks.}, keywords = {VARIATION}, author = {Dawson, William R. and Bennett, Albert F. and Hudson, Jack W.} } @article {71723, title = {Seasonal changes in photosynthate transport within elongating shoots of Populus grandidentata}, journal = {Canadian Journal of Botany}, volume = {52}, year = {1974}, pages = {2547-2559}, keywords = {TRANSPORT}, author = {Donnelly, John Robert} } @proceedings {71730, title = {Biological Methods for the Assessment of Water Quality}, journal = {The Symposium on Biological Methods for the Assessment of Water Quality}, volume = {Special Technical Publication 528}, year = {1973}, note = {(eds.)}, pages = {256}, publisher = {American Society for Testing and Materials (ASTM)}, address = {Los Angeles, CA}, keywords = {WATER QUALITY}, author = {Cairns Jr., John and Dickson, Kenneth L.} } @article {71733, title = {Celestial orientation in recently metamorphosed Bufo americanus}, journal = {Herpetologica}, volume = {29}, year = {1973}, pages = {59-62}, abstract = {Newly metamorphosed Bufo americanus moved predominantly at right angles to their home shore, in the direction toward the shore, when released in water or on land and able to view the sun. When the sun was obscured, no clear evidence of orientational abilities was found. Directional choice appeared to be random when only the stars could be seen.}, keywords = {VERTEBRATES}, author = {Dole, Jim Walter} } @article {71745, title = {Forty years of succession on an abandoned building site at the University of Michigan Biological Station}, journal = {Michigan Botanist}, volume = {12}, year = {1973}, pages = {167-177}, abstract = {Maps of the vegetation for a 38-square-meter plot occupied 1924-1929 by the Botany Laboratory at the University of Michigan Biological Station have shown that: 1. The flora of both vascular and non-vascular plants changed during each interval of time between mapping. Although the number of species was not radically different, the same set of species was not present at each mapping of the area. 2. There is a strong correlation between duration of the plant and its persistence in this area with annuals and biennials being mainly adventives and perennials persisting. 3. Initially the area was covered sparsely by a few individuals of vascular plants with the area mostly bare sand. 4. The first species to become established were weedy colonizers of open exposed areas. Mosses became established later and spread throughout most of the plot. As litter accumulated, vascular plants began to spread. In areas of leaf litter accumulation, greater numbers of individuals of each species have been able to become established. As this continued, tree seedlings became established both in areas of litter accumulation and in the areas of moss cover. 5. Mosses were pioneers of the non-vascular plants with Ceratodon purpureus appearing first, forming a colony covering 94.5\% of the plot in 1950, and then being replaced during the last 20 years by Polytrichum juniperinum and P. piliferum. In recent years, with the accumulation of leaf litter and continued growth of clones of vascular plants, the moss colony has decreased in coverage of the plot. 6. Lichens have also appeared during the last 20 years. Nine species of the genus Cladonia were found growing in and among the members of the moss colony. 7. Disturbance by animals and man has slowed the progress of succession in this area. 8. Assuming little or no disturbance, it may be expected that in the future, aspen suckers and tree seedlings of several species will persist, herbs such as Poa compressa and Melampyrum lineare will increase, and moss and lichen cover will continue to decrease.}, keywords = {VEGETATION}, author = {Duncan, Thomas} } @inbook {71728, title = {Rapid biological monitoring system for determining aquatic community structure in receiving systems}, booktitle = {Biological Methods for the Assessment of Water Quality}, volume = {Special Technical Publication 528}, year = {1973}, pages = {148-163 of 256 pp.}, publisher = {American Society for Testing and Materials (ASTM)}, organization = {American Society for Testing and Materials (ASTM)}, address = {Philadelphia, PA}, keywords = {WATER}, author = {Cairns Jr., John and Dickson, Kenneth L. and Lanza, Guy R.}, editor = {Cairns Jr., John and Dickson, Kenneth L.} } @article {71762, title = {Seiche activity: significant in late summer lake primary production?}, journal = {Bulletin of the Association of Southeastern Biologists}, volume = {20}, year = {1973}, pages = {29}, keywords = {SEICHES}, author = {Delcourt, P. A.} } @article {71763, title = {Sodium dynamics in a northern ecosystem}, journal = {Proceedings of the National Academy of Sciences}, volume = {70}, year = {1973}, pages = {2745-2748}, keywords = {SODIUM}, author = {Botkin, D. B. and Jordan, P. A. and Dominski, A. S. and Hutchinson, G. F. and Lowendorf, H. S.} } @inbook {71729, title = {A tentative proposal for a rapid in-plant biological monitoring system}, booktitle = {Biological Methods for the Assessment of Water Quality}, volume = {Special Technical Publication 528}, year = {1973}, pages = {127-147 of 256 pp.}, publisher = {American Society for Testing and Materials (ASTM)}, organization = {American Society for Testing and Materials (ASTM)}, address = {Philadelphia, PA}, keywords = {WATER}, author = {Cairns Jr., John and Sparks, R. E. and Waller, William T.}, editor = {Cairns Jr., John and Dickson, Kenneth L.} } @article {71779, title = {Evidence of celestial orientation in newly-metamorphosed Rana pipiens}, journal = {Herpetologica}, volume = {28}, year = {1972}, pages = {273-276}, abstract = {Recently-metamorphosed leopard frogs (Rana pipiens) showed an ability to orient along their Y-axis when able to view the sun, but appeared to move randomly under nocturnal skies. Froglets trapped moving away from their natal pond in the season{\textquoteright}s first dispersal wave oriented in the direction of their movement when tested immediately after capture with the sun visible; the directional choice gradually reversed over a period of five days. In later dispersal waves froglets preferred the homeward direction.}, keywords = {VERTEBRATES}, author = {Dole, Jim Walter} } @article {71785, title = {Homing and orientation of displaced toads, Bufo americanus, to their home sites}, journal = {Copeia}, year = {1972}, pages = {151-158}, abstract = {A field study of movements of displaced adult Bufo americans was conducted using a trailing device to follow the animals. Normal toads, after displacements up to 235 m, were able to orient generally homeward, but many animals returned to their former sites by indirect routes, moving first to a shoreline, then turning more directly homeward. Normal toads under both clear skies and complete cloud cover showed similar orientational ability. Neither blinding nor ablation of the olfactory tracts appreciably altered the animals{\textquoteright} ability to home successfully. the specific sense involved in orientation was not identified.}, keywords = {VISION}, author = {Dole, Jim Walter} } @article {71797, title = {The role of olfaction and audition in the orientation of leopard frogs, Rana pipiens}, journal = {Herpetologica}, volume = {28}, year = {1972}, pages = {258-260}, abstract = {Movements of displaced leopard frogs deprived of either the sense of smell or hearing were monitored using a trailing device. Anosmic animals were able to orient and home even on nights with heavy fog and reduced visibility. Deaf animals also oriented homeward.}, keywords = {VERTEBRATES}, author = {Dole, Jim Walter} } @article {71812, title = {The consequences of nonselective periodic removal of portions of fresh-water protozoan communities}, journal = {Transactions of the American Microscopical Society}, volume = {90}, year = {1971}, pages = {71-80}, abstract = {The effects on protozoan communities of periodic harvesting was studied with protozoa colonizing polyurethane substrates in the epilimnion of Douglas Lake, Michigan. Harvesting the substrates by squeezing almost always resulted in an increase in the number of species present when previously harvested substrates were compared with previously unharvested substrates. Thus the perturbation associated with harvesting increased the number of colonizing species.}, keywords = {SUBSTRATE}, author = {Cairns Jr., John and Dickson, Kenneth L. and Yongue Jr., William H.} } @article {71813, title = {Dispersal of recently metamorphosed leopard frogs, Rana pipiens}, journal = {Copeia}, year = {1971}, pages = {221-228}, abstract = {A study of dispersal movements of newly metamorphosed leopard frogs from their natal ponds was made in two ecologically distinct areas. Movements of young emerging from a small marsh in a pasture appeared to be radial, approx. equal numbers moving in all directions, but the travel of many young leaving two beach pools tended to be funneled in one direction along a lake shore. At least a few animals appeared to leave the ponds on almost every night after emergence, but mass emigrations were generally associated with warm, rainy weather. The young frogs traveled commonly up to 800 m in 2-3 days. A few were known to have established their adult residences as much as 5 km from their pond of origin.}, keywords = {VERTEBRATES}, author = {Dole, Jim Walter} } @article {71872, title = {Reduction and restoration of the number of fresh-water protozoan species following acute exposure to copper and zinc}, journal = {Transactions of the Kansas Academy of Science}, volume = {73}, year = {1970}, pages = {1-10}, abstract = {Protozoan communities established in plastic troughs through which Douglas Lake (Michigan) water was pumped were exposed for twenty-four hours to either 24 ppm of Zn+2 or 24 ppm Cu+2. The number of species and approximate density of protozoans in each trough were determined before the zinc or copper was introduced, at the end of the twenty-four hours exposure period, and at each twenty-four hours period after that for either 120 or 144 hours. These results were then compared to those obtained for controls receiving identical treatment except for the omission of heavy metal. A subsidiary test was carried out by exposing a protozoan population in a plastic trough to 24 ppm of zinc with an exposure period of one hour. The results for the 24 ppm Cu+2 test solution show a reduction from 46 to 7 species at the end of the twenty-four hours exposure with a partial recovery to 14 species 144 hours after the test began. The results for the 24 ppm Zn+2 test solution show a reduction in species from 35 to 11 after twenty-four hours exposure with a comparatively rapid recovery to 20 species at 48 hours, 30 at 72, 32 at 96, and 34 at 120. Control species number varied between 32 and 36 during the zinc tests. Copper test controls were similar, varying from 37 to 48. Density changes were not as striking as the reduction in number of species, although more detailed studies may reveal significant changes. The effects of the one hour exposure to zinc were negligible. These preliminary experiments indicate that the residual effects of copper seem to be considerably greater than the residual effects of zinc.}, keywords = {ZINC}, author = {Cairns Jr., John and Dickson, Kenneth L.} } @mastersthesis {71874, title = {Seasonal changes in the pattern of photosynthate transport within elongating shoots of Populus grandidentata}, volume = {Doctor of Philosophy}, year = {1970}, pages = {65 pp.}, school = {University of Michigan}, address = {Ann Arbor, MI}, abstract = {Individual leaves on 5-year-old bigtooth aspen (Populus grandidentata Michx.) suckers in northern Lower Michigan were exposed to 14 CO2 in order to detect seasonal changes in translocation of photosynthates. As new leaves developed at the base of currently-elongating long shoots, they at first acted as translocation sinks and utilized stored carbohydrates. Base (first-formed) leaves began to translocate significant quantities of photosynthate around June 1. By June 15, the direction of net transport had changed from acropetally (to the shoot tip) to basipetally (to the main stem). Leaves midway along the shoot continued to export mainly to the stem tip until early July. Tip (last-formed) leaves did not begin to translocate significant quantities of photosynthates until late July; photosynthates from these leaves were transported mainly toward the main stem. Leaves occupying all shoot positions tested (base, middle, and tip) transported assimilates into their axillary buds--base leaves mainly in June, middle leaves in July, and tip leaves in August. The terminal bud imported photosynthates from all leaves on the shoot, and accumulated several times more C-14 label than did axillary buds at the base of the shoot.}, keywords = {TRANSPORT}, author = {Donnelly, John Robert} } @article {71881, title = {Additions to the phycomycete flora of the Douglas Lake region. VIII. Chytridiomyces annulatus sp. nov. and notes on other zoosporic fungi}, journal = {Nova Hedwigia}, volume = {18}, year = {1969}, pages = {349-365}, keywords = {SPECIES}, author = {Dogma, Irineo} } @article {71905, title = {The relationship of fresh-water protozoan communities to the MacArthur-Wilson equilibrium model}, journal = {The American Naturalist}, volume = {103}, year = {1969}, pages = {439-454}, abstract = {Two series of 10 artificial substrates each were placed in Douglas Lake, Michigan, and their colonization by species of fresh-water protozoans studied. Identifications were made to species whenever possible at intervals of approximately one week, and rough estimates of density were made as well. Although the aggregations of species colonizing each of the substrates were not identical, the colonization process itself was remarkably similar for the entire series. When the number of species was plotted against time in days, a simple exponential curve adequately described the relationship. Colonization rates and extinction rates were compared with the equilibrium model for island faunas proposed by MacArthur and Wilson. These results suggest that the formation and composition of protozoan communities on artificial substrates are the result of interactions comparable to those proposed by MacArthur and Wilson.}, keywords = {SUBSTRATE}, author = {Cairns Jr., John and Dahlberg, M. L. and Dickson, Kenneth L. and Smith, Nancy and Waller, William T.} } @article {71927, title = {Homing in leopard frogs, Rana pipiens}, journal = {Ecology}, volume = {49}, year = {1968}, pages = {386-399}, abstract = {A field study of the movements of displaced adult Rana pipiens was conducted in two summers in northern Michigan, using a thread trailing device to follow the animals. Animals displaced relatively short distances (to about 1 km) from their capture site generally oriented correctly in their homeward direction. No evidence of successful homeward orientation could be found in animals displaced greater distances. Blinded frogs displaced up to 800 m oriented and homed as successfully as normal animals displaced comparable distances, from both upwind and downwind of home. It is suggested that orientation is type I (Griffin 1952). Possible mechanisms serving to guide the homing movements of the frogs are discussed.}, keywords = {VERTEBRATES}, author = {Dole, Jim Walter} } @article {71958, title = {Homing and orientation in Rana pipiens}, journal = {American Zoologist}, volume = {7}, year = {1967}, pages = {199}, abstract = {In a field study of the behavior of displaced Rana pipiens, using a trailing device to follow movements, it was found that adults displaced relatively short distances (to about 1 km) generally oriented correctly in the homeward direction and usually homed successfully. Animals displaced greater distances showed no evidence of homeward orientation. Blinded frogs displaced up to 800 m oriented and homed as successfully as normal frogs, from both upwind and downwind of home. Anosmic animals appeared to be disoriented.}, keywords = {RANA}, author = {Dole, Jim Walter} } @article {71968, title = {Refining correlations of water deficits and radial growth in young red pine}, journal = {Ecology}, volume = {48}, year = {1967}, pages = {525-530}, abstract = {Two sources of variation, one in the pattern of growth, the other in the pattern of rainfall, were reduced by utilizing vertical sequences rather than horizontal sequences of ring width, and utilizing calculated water deficits rather than rainfall per se. Results from two 21-year-old plantations of Pinus resinosa Ait. on a sand soil in Lower Michigan showed a high correlation between ring width over a 10-year period and moisture variables. Moisture deficits alone for the current growing season had a simple correlation of -.83 with ring width, while rainfall alone for the current year had a correlation of .69. Multiple regression analysis accounted for over 80\% of the annual variation in ring width (R=.91) by water deficits and rainfall together, for both the previous and the current growing seasons. Fourteen per cent of the variation was associated with moisture conditions of the previous season (July through September), and 68\% was associated with moisture conditions of the current season (May through September). It is concluded that these correlation coefficients of .80 to .90 are approaching the upper limit for relating single environmental factors, such as moisture, to tree growth.}, keywords = {WATER}, author = {Zahner, Robert and Donnelly, John Robert} } @article {71969, title = {The role of substrate moisture and dew in the water economy of leopard frogs, Rana pipiens}, journal = {Copeia}, year = {1967}, pages = {141-149}, abstract = {In summer, adult Rana pipiens, which normally reside at considerable distances from ponds, depend upon soil moisture as their primary source of water. Water is absorbed through the skin of the groin while sitting on the damp soil. Under controlled laboratory conditions leopard frogs dehydrated to 65-75\% of their hydrated weight, can, on the average, completely recover the lost water in 48 hr when on sand with a moisture content of 20\%; on sand with only 10\% water content, only about 50\% of the lost water is reabsorbed in 48 hr. Dew, absorbed through the groin by sitting on wet vegetation, may be used as a supplementary water source by leopard frogs when available, but is apparently not necessary if sufficiently moist soil is available. Occasionally, under extreme arid conditions in the laboratory, leopard frogs have been observed to bury themselves; such behavior in response to lack of moisture is probably not common in nature, however.}, keywords = {WATER}, author = {Dole, Jim Walter} } @article {71971, title = {Spring movements of leopard frogs, Rana pipiens Schreber, in northern Michigan}, journal = {The American Midlands Naturalist}, volume = {78}, year = {1967}, pages = {167-181}, abstract = {In spring, adult leopard frogs precede the young out of hibernation. During and for several weeks after breeding, frogs of all ages are confined to bodies of water and do not occupy the fields as in summer. Some movement occurs between ponds, involving mainly, perhaps entirely, postbreeding frogs. In 1962, 39\% of the adult leopard frogs in one study area were occupying their home ranges within a week after emergence from hibernation in late April; this was possible because extensive spring flooding permitted breeding in normally less wet regions where many animals had summer ranges, and because many animals had summer home ranges adjoining ponds. In contrast, in a second study area where spring flooding was less extensive and where few animals resided near water, frgos did not abandon the ponds and begin moving to their home ranges until late May and early June; movements to the summer ranges in the fields continued throughout June and, for a few stragglers, into early July. Two adult females were trailed as they moved to their home ranges 150 and 400 m from the ponds. Details of their routes are given.}, keywords = {RANA}, author = {Dole, Jim Walter} } @article {72031, title = {Ecology of three sympatric species of parasitic insects of the genus Megarhyssa (Hymenoptera: Ichneumonidae)}, journal = {Ecology}, volume = {46}, year = {1965}, pages = {140-150}, abstract = {Three species, Megarhyssa atrata lineata, M. macrurus lunator, and M. greenei greenei were studied in beech-maple forests in Michigan. All are diurnal with similar activity patterns except that female M. atrata maintain a high degree of activity later in the day than do the others. Saturation deficits above 10 g/m3 inhibit activity whereas normal summer daytime temperatures do not. There does not seem to be a significant difference between time of emergence of females and of males in the spring, nor are there differences in seasonal occurrence of the various species except that M. greenei may persist slightly longer in the fall. Insects of both sexes and of all species tend to return repeatedly to the same log or stump with but a limited amount of movement between sites. Adults rest on the undersides of beech and maple leaves during inactive periods. Since there are more such places than individuals to use them, competition for shelter does not seem to occur. Neither do adults compete for food. The larvae of the three species are largely segregated ecologically in that they parasitize different segments of the host population. This depends on the facts that (1) the adults select a host larva at a depth in the wood so that complete insertion of the ovipositor at right angles to the surface of the wood will just reach it, (2) the ovipositors of the different species are of different lengths, and (3) the host larvae maintain themselves at about the same depth in the wood for most of their larval period. There is succession of species on a given log but not to the extent that the three species would be ecologically segregated without the above mechanism. The sequence of species in the succession seems to depend on differences in ovipositor length. Females are usually more abundant on logs when a species is invading a new log; males are usually more numerous in the declining phase. Adults can live at least 27 days. Predators in the area were robber flies and perhaps a chipmunk. Incidence of parasitism of Tremex by Megarhyssa was 26.7\% in part of a log which was examined.}, keywords = {TREMEX}, author = {Heatwole, Harold Franklin and Davis, Donald M.} } @article {72032, title = {Effect of pruning the parent root on growth of aspen suckers}, journal = {Ecology}, volume = {46}, year = {1965}, pages = {373-375}, abstract = {Various portions of the root systems of bigtooth aspen (Populus grandidentata) suckers were severed, and the subsequent height and radial growth of stems were measured. Aspen vegetative regeneration is heavily dependent on the parent roots for at least 25 years following initial suckering. The distal portion of the parent root contributes more to sucker growth than does the proximal. New roots at the base of suckers contribute little during the first 6 years, then become progressively more important with age, and by 25 years account for about half of the annual stem growth.}, keywords = {VEGETATIVE REPRODUCTION}, author = {Zahner, Robert and De Byle, Norbert Valentine} } @article {72051, title = {Short-tailed shrew attacks garter snake}, journal = {Journal of Mammalogy}, volume = {46}, year = {1965}, pages = {329}, keywords = {THAMNOPHIS}, author = {De Byle, Norbert Valentine} } @article {72055, title = {Spatial relations in natural populations of the leopard frog, Rana pipiens Schreber, in northern Michigan}, journal = {The American Midlands Naturalist}, volume = {74}, year = {1965}, pages = {464-478}, abstract = {A study of two populations of Rana pipiens revealed that the size of the home range, permanence of occupancy of the home range, and the place of residence differed considerably in two ecologically different environments. In one study area (Sedge Point) where the area available for habitation was relatively small and confined by less suitable habitat, and where standing water was readily available, home ranges were smaller and more commonly reoccupied year after year by the same frogs from their second season through adulthood, than in the second study area (Budzinski{\textquoteright}s) where suitable habitat was more widespread, less confined, and where ponds were less readily available. In the latter region, but apparently not in the former, larger frogs tended to occupy less wet regions at greater distances from ponds than did smaller frogs.}, keywords = {SPATIAL}, author = {Dole, Jim Walter} } @article {72058, title = {Summer movements of adult leopard frogs, Rana pipiens Schreber, in northern Michigan}, journal = {Ecology}, volume = {46}, year = {1965}, pages = {236-255}, abstract = {The purpose of this study was to determine the nature of the movements of adult Rana pipiens in summer and the factors controlling them. Movements in a population in Cheboygan County, Michigan, were studied by means of a trailing device for following individual frogs, by weekly censuses of the study areas, and by direct observation. Trailing was accomplished by means of a spool of thread, mounted in a holding device on the backs of adult frogs; this unwound as the animals moved, marking their routes. One hundred thirty-six frogs were trailed for a total of 681 frog-days (one frog/one day); individuals were trailed continuously for periods up to 35 days. In fair weather in summer, leopard frogs on their home ranges in the fields typically spent more than 95\% of a day{\textquoteright}s time sitting quietly in "forms," made by clearing the wet soil of dead vegetation. Several reamined in the same form for more than 24 hr, one for more than five days. Travel on the home range occurred only infrequently during each day, and usually consisted of a shift from one resting spot (form) to another, seldom more than 5 to 10 m apart and usually much less. Such movement took place at all times of the diel period, but almost two-thirds of the total distance moved by frogs on their home range was covered between 8 pm and 8 am, presumably during the night. Movement within the home range formed complicated patterns of turns, doublings, and criss-crossed paths. Many frogs returned repeatedly to particular parts of their range, often to certain forms which seemed to have some significance as homes. Occasional brief trips into adjoining regions uninhabitable by frogs may have been exploratory, or attempts to reoccupy former parts of the home range which were no longer suitable for occupancy. Leopard frogs which had home ranges in wet woods seldom constructed forms but, instead, frequently used crevices and cavities as retreats. It is suggested that Rana pipiens may be a more common resident in wet forests than is generally realized, but is seldom seen in such places owing to its secretive habits. In nocturnal rains leopard frogs occasionally made extended excursions off their ranges. Such movement differed from home range movement in being direct, more or less continuous through the night, and often covering distances of 100 m or more; one trailed frog moved 159 m in a single night. These migratory movements stopped at daybreak, the frogs commonly remaining in the region they had reached for several days, unless forced by unfavorable moisture conditions to move to more moist regions. Occasionally the migration was continued on the night following the initial movement; one trailed frog traveled 240 m in two consecutive nights. Heavy rains of long duration in which almost the total population emigrated produced a marked, though temporary, effect on dispersion. Although leopard frogs were almost entirely confined to regions of moist soil in fair weather, during and immediately after heavy rains they scattered widely. Migratory frogs, even those which reached areas suitable for permanent occupancy, showed a strong tendency to return to their ranges following nocturnal excursions. Of 30 subadult and adult frogs captured off their range during or after rains, 25 were later taken on their home range or had moved toward it. The function of the nocturnal migratory excursions is not known; they probably enable the animals to become acquainted with a large area around their home ranges. The most rapid rate of movement determined for a trailed frog during a migration was 46.6 m/hr. The distance traveled, hence rate of movement, showed a signficant positive correlation with temperature. Rain appeared to be the environmental factor initiating migratory movement.}, keywords = {VERTEBRATES}, author = {Dole, Jim Walter} } @article {72069, title = {Detection of functional intraclonal aspen root connections by tracers and excavation}, journal = {Forest Science}, volume = {10}, year = {1964}, pages = {386-396}, abstract = {Root suckering of both Populus tremuloides Michx. and P. grandidentata Michx. commonly produces clones of genetically identical stems, joined, to some extent, through the parent root system. Excavation of roots revealed parent root connections among P. grandidentata stems up to 50 years old. A number of dead stumps with live root systems, joined to living trees through the parent roots, existed on these exposed anastomotic networks. A tracer injected into donor stems in 119 P. grandidentata clones in 4 stands of varying ages allowed discovery of the root connections between the donor and any receptor stems. There were 105 receptor trees distributed among 71 aspen clones injected with eosin bluish dye, 48 receptors among 24 clones injected with sodium arsenite, and 17 among 24 clones injected with radioactive Rb86. Tracers indicated that P. grandidentata clones of sucker origin consist of a number of interconnected stem groups. The parent root connections among healthy trees aparrently do not decay. Tracer transport implied that transport of materials probably occurs among stems under natural conditions.}, keywords = {VEGETATIVE REPRODUCTION}, author = {De Byle, Norbert Valentine} } @article {72070, title = {Detection of mates and hosts by parasitic insects of the genus Megarhyssa (Hymenoptera: Ichneumonidae)}, journal = {The American Midlands Naturalist}, volume = {71}, year = {1964}, pages = {374-381}, abstract = {There is a generalized stimulus which attracts the males of Megarhyssa atrata (Fabricius), M. macrurus (Linnaeus) and M. greenei Viereck to form mixed aggregations and to engage in precopulatory behavior at the sites of emerging females of any of these species. In addition there is a species-specific stimulus which causes initiation of copulation by males of the same species as the emerging female. The generalized stimulus was identified as the chewing sound made by the female during excavation of her emergence burrow in the wood. The specific stimulus was not identified although sound within the range of 50-15,000 cps and vision were eliminated as possibilities. The females of these three species can locate accurately the host larvae in the wood and direct their ovipositors to them. The sense involved is either olfaction, detection of sound outside the range of 60-10,000 cps or some unknown sensory mechanism. Females oviposit only on hosts that are at a depth in the wood such that they can just be reached by the ovipositor when it is completely inserted.}, keywords = {PARASITES}, author = {Heatwole, Harold Franklin and Davis, Donald M. and Wenner, Adrian M.} } @mastersthesis {72085, title = {Movement and spatial relations of Rana pipiens in spring and summer in northern Michigan}, volume = {Doctor of Philosophy}, year = {1964}, pages = {288 pp.}, school = {University of Michigan}, address = {Ann Arbor, MI}, abstract = {The purpose of this study was to determine the nature of the movements and spatial relations of Rana pipiens and the factors controlling them. Movements in two populations in Cheboygan County, Michigan, were studied by means of a trailing device for following individual frogs, by trapping, by weekly censuses of the study areas and by direct observation. In the summers of 1960 and 1961, and the spring and summer of 1962, more than 6000 frogs were marked for individual recognition by toe clipping. Trailing was accomplished by means of a spool of thread, mounted in a holding device on the backs of adult frogs, which unwound as the animals moved, marking their routes. 136 frogs were trailed for a total of 681 frog-days (one frog/one day); individuals were trailed continuously for periods up to 35 days. Budzinski{\textquoteright}s study area was within a 4.25 hectare pasture containing an abandoned gravel pit and small marsh, both having water much of the summer. The Sedge Point study plot was a 1.2 hectare region surrounding two beach pools on a point of land extending into a lake and bounded on its inland side by a red maple woods. In spring, adult frogs preceded the young out of hibernation. During, and for three to four weeks after breeding, all sizes of Rana pipiens were confined to bodies of water and did not occupy the fields as they did during summer. This seasonal difference in habitat may be the result of seasonal physiological changes, differences in availability of cover or food, or environmental temperature differences. Sometime between May 21 and June 4 in 1962, Leopard Frogs at Budzinski{\textquoteright}s abandoned the ponds and began moving to their home ranges in outlying regions; a few did not reach their ranges until early July, possibly because a lack of rain in June prevented earlier movement. At Sedge Point 39\% were on their home ranges within a week after emergence from hibernation in late April; this was possible because of extensive spring flooding of the area and the fact that over 90\% of the resident frogs had ranges adjoining ponds, enabling them to remain in water while on their ranges. In summer, frogs in their second season, or older, limited most of their activities to a home range. At Budzinski{\textquoteright}s, ranges of second-season frogs were less permanent than those of adults, for most females and many males moved to areas more remote from water upon reaching adulthood; the shift probably occurred early in their third season. At Sedge Point, where the region inhabited by Leopard Frogs was smaller and more confined by unsuitable habitats, second-season ranges were commonly reoccupied. Adults in both study plots tended to reoccupy the same home range year after year; only one adult, a female, was known to have shifted her range within a study area. One male, absent from his range in the second summer of the study, returned to it in the third year; presumably he occupied another range elsewhere in the year he was absent.}, keywords = {VERTEBRATES}, author = {Dole, Jim Walter} } @article {72132, title = {The behavior of Megarhyssa, a genus of parasitic hymenopterans (Ichneumonidae: Ephialtinae)}, journal = {Zeitschrift fur Tierpsychologie}, volume = {19}, year = {1962}, pages = {652-664}, abstract = {The behavioural patterns of Megarhyssa macrurus lunator, M. atrata lineata, and M. greenei greenei, all parasitic on wood-boring larvae of Tremex columba, were directly observed in nature and are herein described with a presentation of their functional significance. All three species had practically identical patterns of behaviour except where differences in morphology imposed modifications of a mechanical nature. Exploratory behaviour involves chiefly the tips of the antennae; the sensory organs located there are probably used to detect hosts although accessory receptors on the tip of the males{\textquoteright} abdomen may also be involved in detection of females. Two stimuli seem to be involved in mate detection and selection; a generalized one which attracts males of all three species to the log and brings them to a state of sexual responsiveness, and a species-specific one which stimulates males of only the appropriate species to initiate copulation. The latter is liberated only after the female cuts through the surface of the log.}, keywords = {TREMEX}, author = {Heatwole, Harold Franklin and Davis, Donald M. and Wenner, Adrian M.} } @article {72170, title = {Hinge-tooth reversals in populations of Ohio Sphaeriidae}, journal = {American Malacological Union Annual Report}, year = {1961}, pages = {19-20}, keywords = {SPHAERIIDAE}, author = {Eggleton, Frank E. and Davis, George M.} } @mastersthesis {72194, title = {Tracing and evaluating functional root connections among stems within aspen clones}, volume = {Doctor of Philosophy}, year = {1961}, pages = {269 pp.}, school = {University of Michigan}, address = {Ann Arbor, MI}, abstract = {Root suckering of both quaking aspen (Populus tremuloides Michx.) and largetooth aspen (P. grandidentata Michx.) commonly produces clones of genetically identical stems. Due to this origin, the stems in each clone are, to some extent, joined through the parent root system. This study was conducted to clarify and evaluate the physiological importance of these parent root connections, and to determine their persistence through 40 to 50 years of stand age. Data were gathered from aspen clones which had been vegetatively reproducing for one or more generations in northern Lower Michigan. Some root systems were excavated, but the majority of interstem connections were discovered through the use of dye, phytocide, and radioisotope tracers. A number of tracer injection techniques were tested, with the use of cone-frustum reservoirs attached near the bases of stems being found most satisfactory for introducing tracer solutions into donor trees. Tracers were inoculated into more than 120 largetooth aspen clones which were divided among 3 age classes, ranging from 6 to 40 years, on 4 sites. Excavation of root systems revealed parent root connections among largetooth aspen stems up to 50 years old. A number of dead stumps with live root systems, which were in turn joined to living trees through the parent roots, existed on these exposed anastomotic networks. Excavation on one site exposed root grafts that had united several 40-year old largetooth aspen trees with their neighbors. Eosin bluish dye and sodium arsenite were the best tracers. Both were readily absorbed by the xylem of the donor trees and transported through the roots to attached receptor trees in which their presence was visibly evident. Radioactive rubidium-86 could only be detected in receptors through time-consuming monitoring. There were 105 receptor trees distributed among 71 largetooth aspen clones injected with eosin, 48 receptors among 24 clones injected with sodium arsenite, and 17 among 24 clones injected with Rb-86. The use of tracers indicated that largetooth aspen clones of sucker origin each consist of a number of interconnected stem groups. These groups may vary in size from 2 to 10 stems, with the average being 3. The number of stems per group decreased slightly with age, but there was no evidence for decay of parent root connections among healthy trees. The increase in percentage of receptor stems in older stands suggested that interconnected groups had a greater survival capacity than independent aspen trees. Stem to stem transfer of needed materials may contribute to this capacity. Tracer transport implied that translocation of materials may occur among stems under natural conditions. Survival and growth of root pruned, stem girdled, and defoliated largetooth aspen trees were used as criteria for the physiological importance of the parent root system for sucker stems from 3 to 25 years old. Removal of both ends of the parent root significantly reduced growth and was frequently fatal to the treated tree. The few roots that originate from the base of these young suckers were also found to influence growth. Defoliating and girdling allowed a comparison of growth resulting from stored foods with that from currently sysnthesized foods. Leaf areas and leaf weights of aspen suckers were also determined as part of this experiment.}, keywords = {SUCKERING}, author = {De Byle, Norbert Valentine} } @article {72209, title = {Late summer oviposition in the salamander, Plethodon cinereus}, journal = {Herpetologica}, volume = {16}, year = {1960}, pages = {141-142}, keywords = {SALAMANDERS}, author = {Davidson, Marilyn and Heatwole, Harold Franklin} } @mastersthesis {72230, title = {Tsuga canadensis in middle Michigan. The relationship of its ecology to its status as a natural resource}, volume = {Master of Science}, year = {1960}, pages = {77 pp.}, school = {University of Michigan}, address = {Ann Arbor, MI}, abstract = {Eastern hemlock is one of many organisms whose fate has depended upon how it has fitted into the world of man. To the timberman in pursuit of white pine, it had no significance. To the settler it was, along with the hardwoods, a natural enemy -- its presence meant just that much more travail necessary to reach the goal of pastures and fields. To the tanner hemlock was the source of one of the mainstays of his industry, and hemlock trees in the forest meant a rich mine of bark to be exploited. When the white pine was gone, the presence of hemlock and the northern hardwoods provided a resource to keep the lumber man in business just as a miner turns to poorer grade ores after the rich veins have been exploited. Trees were more of an "ore" than a crop in the days of the greatest use of hemlock. Only after most of the old-growth timber of the US had been exploited did it become economically feasible to produce trees on a sustained-yield basis. Hemlock, however, with its inability to adapt to a man-made environment, and its low value as a natural resource, is no longer of any great concern to man. It has come to be, in Middle Michigan, very nearly the "neutral stuff" which it was in pre-settlement times.}, keywords = {TSUGA}, author = {Davidoff, Mary Libbe} } @article {72381, title = {Further notes on amyloid tramal hyphae in Gomphidius}, journal = {Mycologia}, volume = {46}, year = {1954}, pages = {484-487}, keywords = {GOMPHIDIUS}, author = {Smith, Alexander H. and Dreisinger, Bruce R.} } @mastersthesis {72432, title = {Studies on the biology of Physa gyrina Say; ecology and life history}, volume = {Doctor of Philosophy}, year = {1953}, pages = {110 pp.}, school = {University of Michigan}, type = {Doctor of Philosophy}, address = {Ann Arbor, MI}, abstract = {Of the four families constituting the higher fresh-water basommatophora, the one on which the least amount of critical work has been done, is the family Physidae. The present investigation began as an attempt to study the genus Physa in Michigan. Some field and experimental work was carried on in 1940 and 1941 but the major portion was completed from 1949 to 1952. It became evident within a short time that, due to the chaotic state of the systematics within the group, the problem must necessarily be limited in its scope if any work of a truly critical nature was to be accomplished. Several lines of investigation have been pursued here. The life history has been ascertained through laboratory rearings supplemented by a field study of a selected natural population. An attempt to determine the ecological relationships of Physa gyrina was made through an extended survey of the waters in the vicinity of Ann Arbor and those of the Douglas Lake region. It is hoped that, by the combination of these various approaches, the biology of the species will be more adequately understood.}, keywords = {SNAILS}, author = {DeWitt, Robert M.} } @article {72467, title = {The nonparasitic lamprey Ichthyomyzon fossor in the Mississippi drainage of Illinois}, journal = {The Anatomical Record}, volume = {111}, year = {1951}, pages = {54}, keywords = {LAMPREY}, author = {Dittlinger, Ann and Creaser, Charles W.} } @article {72469, title = {Notes on Haemoproteus metchinikovi in turtles from Wisconsin, Michigan, and Louisiana}, journal = {Journal of Parasitology}, volume = {37}, year = {1951}, pages = {12(Abstr}, keywords = {TURTLES}, author = {DeGiusti, Dominic L. and Batten Jr., Peter J.} } @article {72514, title = {A gregarine parasite in the amphipod, Hyalella azteca}, journal = {Journal of Parasitology}, volume = {35}, year = {1949}, pages = {31 (Abstr}, abstract = {Hyalella azteca collected from Douglas Lake, Michigan, have been found to harbor within their intestine a cephaline gregarine. The sporonts are broadly oval-shaped and average twenty microns in length. A circle of deeply-staining granules at the anterior end of the protomerite suggests the presence of an epimerite during an earlier stage. A syzygy consists of two individuals. Cysts averaging thirty microns in diameter are formed in the hindgut. Their devel from the gametocyst through spore duct formation has been observed. Twenty-four hours after a cyst is formed three thickened circular areas representing the basal disks of the spore ducts appear on its surface. Growth of the spore tubes begins at these basal disks and progresses inward towards the center of the cyst. Work is at present being conducted to experimentally complete this life cycle. This form agrees with Kamm{\textquoteright}s description of the genus, Gregarina. Since Hyalella azteca is a new host record for any gregarine, this parasite is proposed as a new species, Gregarina Hyalellae. The measurements given above indicate that Gregarina hyalellae is the smallest described gregarine.}, keywords = {SPECIES}, author = {Batten Jr., Peter J. and DeGiusti, Dominic L.} } @article {72517, title = {The life cycle of Leptorhynchoides thecatus (Linton), an acanthocephalan of fish}, journal = {Journal of Parasitology}, volume = {35}, year = {1949}, pages = {437-460}, abstract = {1. The life cycle of Leptorhynchoides thecatus has been experimentally reproduced in the laboratory. 2. The amphipod, Hyalella azteca, serves as the intermediate host, and the rock bass, Ambloplites rupestris, as the definitive host. 3. The eggs of Leptorhynchoides thecatus are ingested by the amphipod intermediate host. Hatching takes place within the intestine. The acanthor of Leptorhynchoides thecatus penetrates the epithelium of the host and locates between it and the serosa of the intestine. 4. The embryo undergoes a period of growth and development attached to the host intestine, producing a rounded bladder-like acanthella projecting into the hemocoele of the host. 5. Fourteen days after entering the intermediate host the acanthella separates from its attachment to the intestine of the amphipod, and enters into a period of development free within the hemocoele of the host. 6. Thirty-two days after the embryo is ingested by the amphipod it has developed into a juvenile acanthocephalan capable of infecting the fish definitive host. 7. The juveniles of Leptorhynchoides thecatus within the hemocoele of Hyalella azteca contain all the organs of the adult with one exception: the juvenile females do not have the ovary completely formed. 8. Upon ingestion of Hyalella azteca by the fish host, the juvenile ACANTHOCEPHALA are released into the fish stomach and attach to the walls of the pyloric cecae. 9. Four weeks after entering the fish host the juvenile male acanthocephalan has completed its development. During this period, the female completes formation of the ovary and eight weeks after entering the fish it passes mature eggs.}, keywords = {VERTEBRATES}, author = {DeGiusti, Dominic L.} } @article {72524, title = {Partial development of Echinorhynchus coregoni in Hyalella azteca and the cellular reaction of the amphipod to the parasite}, journal = {Journal of Parasitology}, volume = {35}, year = {1949}, pages = {31 (Abstr}, abstract = {Echinorhynchus coregoni is an acanthocephalan parasitic in the digestive tract of coregonid fish. Juveniles of this form have been found in the amphipod, Pontoporeia heyii. In the present work it was found that the eggs of this acanthocephalan will hatch when ingested by Hyalella azteca. The acanthor penetrates the amphipod gut wall and locates just beneath the serosa. In most instances the acanthor ceases to develop, is walled, and is destroyed by cellular reaction of the host. The host reaction consists of giant cells which coalesce to form a syncytium. A small per cent of the infeoted amphipods do not overoome the infection. In these hosts the acanthor enters the acanthella stage and has been followed through eight days of development with no apparent signs of injury. The mechanism of liberation of the acanthor from its embryonic membranes was observed within the amphipod intestine. The acanther of Echinorhynchus coregoni has a prominent rostellum armed with b1adelike hooks. Its body is covered with fixed spines, large at the anterior extremity and progressively deoreasing in size posteriorly. Hyalella azteca appears to be an abnormal intermediate host for Echinorhynchus coregoni, but it serves as a good tool both for the study of the cellular reaotion of the amphipod to an acanthocephalan parasite and as a means of liberating the acanthor from its embryonic membranes tor study.}, keywords = {PONTOPOREIA}, author = {DeGiusti, Dominic L.} } @article {72602, title = {The fate of animals in stream drift when carried into lakes}, journal = {Ecological Monographs}, volume = {14}, year = {1944}, note = {Some nice maps of the mouth of Carp Creek.}, pages = {333-357}, abstract = {1. Special methods for sampling stream drift and stream and lake bottom are described. 2. A total of 71 kinds of macroscopic aquatic animals, distributed in seven phyla, have been recorded from drift in 3 streams. 3. Presence of animals in stream drift, although highly variable in quantity and quality, was the constant situation. Large quantities of drift material, including animals, are carried into Burt Lake by Carp Creek. 4. In general the same larger groups of animals were represented in all 3 streams, but there was considerable stream individuality as to species. With insignificant exceptions, all species which occurred in the bottom samples from Carp Creek were sooner or later found in the drift of that stream. 5. Most of the drift animals which entered Burt Lake settled to the bottom immediately lakeward from the margin of the delta, where a zone of concentration was established. Distribution of drift animals on the lake bottom beyond the zone of concentration was not dependent upon the distribution of creek water in the lake. 6. Fall of surface level of Burt Lake affected the drift animals in the following ways: (a) increased speed of the creek current and of bottom erosion for at least 85 meters upstream from the mouth; (b) altered quantity and probably quality of drift animals entering the lake; (c) caused lakeward extension of the delta; and (d) exposed drift animals, in concentration zone, to more vigorous wave action. 7. Observations and experiments showed that drift animals could maintain positions on the lake bottom during the absence of, or while protected from, wave action. 8. Wave action affected the drift animals inthe following ways: (a) prevented burrowing; (b) partially or completely depopulated the zone of concentration; (c) washed animals upon the beach near the creek; and (d) changed the position of the delta materials to form islands, spits, and sand bars upon which creek animals were stranded. 9. Creek animals on the beach met the following fates: (a) were buried in beach material; and (b) succumbed to desiccation. Predatory activities of fishes accounted for disappearance of only a minor portion of the drift animals which entered the lake. 10. Most of the animals drifting from Carp Creek into Burt Lake did not survive for extended periods of time. The major factor in the lake environment which determined the fate of drift animals was wave action.}, keywords = {STREAMS}, author = {Dendy, Jack S.} } @article {72726, title = {Preliminary note on the life cycle of Leptorhynchoides thecatus, an acanthocephalan parasite of fish}, journal = {Journal of Parasitology}, volume = {25}, year = {1939}, pages = {180}, keywords = {PARASITES}, author = {DeGiusti, Dominic L.} } @article {72735, title = {Territorial studies on the Eastern Goldfinch}, journal = {The Wilson Bulletin}, volume = {51}, year = {1939}, pages = {69-77}, keywords = {TERRITORIALITY}, author = {Drum, Margaret} } @article {72743, title = {An ecological study of Wolf{\textquoteright}s Bog, Cheboygan County, Michigan}, journal = {Transactions of the Kansas Academy of Science}, volume = {41}, year = {1938}, pages = {87-95}, keywords = {VEGETATION}, author = {Dutro, Ruth and Cohoe, Edith} } @article {72755, title = {Notes on the behavior of the Nighthawk}, journal = {The Chicago Naturalist}, volume = {1}, year = {1938}, pages = {65-66}, keywords = {NIGHTHAWKS}, author = {Duncan, Donald P. and Mathiak, Harold A.} } @article {72789, title = {A forest soil study of the University of Michigan Biological Tract}, journal = {Papers of the Michigan Academy of Science, Arts and Letters}, volume = {21}, year = {1936}, pages = {269-278}, keywords = {VEGETATION}, author = {Donahue, Roy L.} } @article {72803, title = {Pathological studies on the penetration of the cercaria of the strigeid trematode, Diplostomum flexicaudum}, journal = {Journal of Parasitology}, volume = {22}, year = {1936}, pages = {329-337}, keywords = {VERTEBRATES}, author = {Davis, Dorland J.} } @article {72805, title = {Report on the preparation of an histolytic ferment present in the bodies of cercariae}, journal = {Journal of Parasitology}, volume = {22}, year = {1936}, pages = {108-110}, keywords = {TREMATODES}, author = {Davis, Dorland J.} } @article {72872, title = {An ecological study of Bryant{\textquoteright}s Bog, Cheboygan County, Michigan}, journal = {Papers of the Michigan Academy of Science, Arts and Letters}, volume = {17}, year = {1933}, pages = {57-65}, keywords = {VEGETATION}, author = {Coburn, Helen R. and Grant, Gertrude M. and Dean, Doris L.} } @article {72918, title = {The effect of increased activities and change in mode of transportation upon the distribution of introduced species in the vicinity of Douglas Lake, Michigan}, journal = {Bulletin of the Torrey Botanical Club}, volume = {57}, year = {1931}, pages = {339-346}, keywords = {VASCULAR PLANTS}, author = {Coburn, Helen R. and Dean, Doris L.} } @article {72992, title = {An ecological study of Linne Bog, Cheboygan County, Michigan, with special reference to Nemopanthus mucronata (L.) Trelease}, journal = {Papers of the Michigan Academy of Science, Arts and Letters}, volume = {8}, year = {1928}, pages = {87-96}, keywords = {WETLANDS VEGETATION}, author = {Dean, Doris L. and Coburn, Helen R.} } @article {73028, title = {An ecological study of Smith{\textquoteright}s Bog, Cheboygan County, Michigan}, journal = {Papers of the Michigan Academy of Science, Arts and Letters}, volume = {5}, year = {1926}, pages = {201-210}, keywords = {WETLANDS}, author = {Woollett, Edith C. and Coburn, Helen R. and Dean, Doris L.} } @article {73043, title = {Application of Gleason{\textquoteright}s formula to a Carex lasiocarpa association, an association of few species}, journal = {Bulletin of the Torrey Botanical Club}, volume = {52}, year = {1925}, pages = {23-25}, keywords = {WETLANDS}, author = {Woollett, Edith C. and Coburn, Helen R. and Dean, Doris L.} } @article {73197, title = {Mosquitoes pollinating orchids}, journal = {Science}, volume = {37}, year = {1913}, pages = {867}, keywords = {POLLINATION}, author = {Dexter, John Smith} } @article {73200, title = {Permanent vegetation quadrats at Douglas Lake}, year = {1913}, keywords = {VEGETATION}, author = {Dietz, Ada K.} }