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Dynamic Analysis of Vegetation Coverage Change in Miyun Reservoir Basin from 2000 to 2005 Based on Remote Sensing

Vegetation includes all plant communities that cover the earth surface. Vegetation coverage is the most important index to scale the status of the vegetation of the region, so the vegetation is the composition and the function body of ecological system. Vegetation coverage in different land use types of Miyun reservoir watershed were calculated based on remote sensing images (Landsat 5 TM images) in 2000 and 2005 by employing NDVI method for dimidiate pixel model, and the vegetation coverage maps of different periods were generated to analysis the temporal change of vegetation coverage of Miyun reservoir watershed. The results showed that, from 2000 to 2005, the vegetation coverage of every land use types were increased except the water area, and especially for the sand land and arable land, the growth were 29.5% and 27.3, respectively. And the average vegetation coverage is not high in the Miyun reservoir watershed, especially in the western region, the vegetation coverage is poor, and the soil erosion and land desertification situation is more serious.