Spatiotemporal Variation Characteristics and Impact Factors of Vegetation Coverage in the Three Gorges Reservoir Area

Trend analysis was used to explore the spatial and temporal patterns of vegetation normalized difference vegetation index(NDVI) in the Three Gorges Reservoir Area(TGRA) and its relationship with elevation.Through Mann-Kendall test, the mutation points of NDVI change was identified.The correlation and its driving partition of regional NDVI and climate, human factors were clarified.The results show that:(1) From 2000 to 2019,the average NDVI in the TGRA showed a rising trend of fluctuation, and its spatial distribution heterogeneity was obvious, which shows a increase first and then decrease slightly with regional elevation rising;(2) The increasing trend of NDVI was obvious from 2000 to 2008,and its growth rate slowed down after 2009;(3) Areas where climate was the main factor affecting NDVI accounted for 8.9% of the total research area, whereas human activities were the primary factor influencing NDVI changes.Among them, ecological projects such as returning farmland to forests have a positive effect, while urbanization and economic development have a negative effect.It is urgent to take corresponding measures to realize the benign interaction between the regional economy and the ecosystem.