Spatiotemporal Patterns and Driving Forces of Vegetation Restoration and Degradation in Dongting Lake Wetland

【Objective】Wetland vegetation can purify the environment, regulate climate, and improve the soil, which is of great significance to the ecological security and stability of the wetland system. Wetland vegetation communities are, however, under serious threat from accelerated global warming and human disturbance. Probing the long-term spatial-temporal pattern of wetland vegetation cover change and its response to climate change and human activities are important for informing decisions on wetland protection.【Method】It is difficult to collect long-term, reliable optical observations with high spatiotemporal resolution in the Dongting Lake wetland due to its location in the subtropical monsoon climate zone and its frequent cloud and rainy conditions.Firstly, this study used the flexible spatiotemporal data analysis fusion（FSDAF） algorithm to fuse Landsat and MODIS images to obtain the monthly normalized difference vegetation index（NDVI） time series during the study period（2000-2019）. To quantify the response of