Spatiotemporal variation in the terrestrial vegetation phenology in Danjiangkou reservoir from 2001 to 2012

Based on a sixteen-day constrained view angle maximum value composite (CV-MVC) MODIS vegetation index time-series data from 2001 to 2012, we use dynamic threshold method to extract the spatial patterns of terrestrial vegetation phenology in Danjiangkou reservoir. After analysis the pattern of three phenology metrics (start of growth season, end of growth season and length of growth season), we find the spatiotemporal variation of phenological in reservoir area is mainly reflected on the delay of start of growth season, the ahead of end of growth season. In south-to-north water transfer project affected area in Han River, Danjiang River and periphery of reservoir area are mainly reflected on growth season starting period is ahead, growth season end time is ahead, and length of growth season is prolonged. The analysis of the changes indicates that in the core of reservoir, forest and shrub have restored because of ecological migration, conversion cropland to forestland forestation. At the same time, large influxes of ecological migration from the reservoir to city and country, caused the ecological environment in reservoir core area has been greatly improved. Our research shows the ecological engineering has make signification role in promoting the changes of ecosystem in Danjingkou reservoir.