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Based on MODIS NDVI data to monitor the growing season of the deciduous forest in Beijing, China

Phenology is the important indicator of reflecting climate and environment change. Development of remote sensing provides a new method for mapping phenology. Normalized difference Vegetation Index (NDVI) derived from the Moderate Resolution Imaging Spectroradiometer (MODIS) is a key indicator to vegetation monitoring and phenology analysis. This paper uses time-series of MODIS NDVI 16 days vegetation indices of 250 meters, making use of double Logistic model, extracting deciduous forest phenology of Beijing area in the year 2001-2009. The results show that in most of Beijing area, deciduous forest growing season start date begins between 110th and 160th day; Growing season end date begins between 280th and 330th; Length of growing season in most parts of deciduous forest is mainly between 120th and 200th day. Among them, 2001 and 2006 growing season start date, growing season end date have a large difference from previous years, and have relations with precipitation and length of day. Compared the results with phenology field observation data, the results have a certain reliability.