Based on SPOT/VGT NDVI time series images from 1999 to 2009 in the Three Gorges Area (TGA), we detected vegetation activity and trends using two methods, the Mann-Kendall and Slope tests. The relationships between vegetation activity trends and annual average temperature and annual total precipitation were analyzed using observational data in seven typical meteorological stations. Vegetation activity presents a distinctive uptrend during the study period, especially in Fengjie, Yunyang, Wushan, Wuxi, and Badong counties located in the midstream of the Three Gorges Reservoir. However, in the Chongqing major area (CMA) and its surrounding areas and Fuling, Yichang, and part of Wanzhou, vegetation activity shows a decreasing trend as a result of urban expansion. The NDVI has two fluctuation troughs in 2004 and 2006. The annual mean temperature presents a slight overall upward trend, but the annual total precipitation does not present a significant trend. And they almost have no significant correlations with the NDVI. Therefore, temperature and precipitation are not major influences on vegetation activity change. Instead, increasing vegetation cover benefits from a number of environment protection policies and management, and ecological construction is a major factor resulting in the upward trend. In addition, resettlement schemes mitigate the impact of human activity on vegetation activity. 1. Introduction The Three Gorges Project (TGP), located at Sandouping Village, Yichang City, on the Yangtze River, China, began in 1994 and ended in 2009. Currently, the water level in the reservoir has increased up to 175？m; the total storage capacity of the reservoir is approximately 39.3？billion？m3, and the reservoir stretches 660？km upstream, is on average 1.1？km wide, and encompasses a total area of 1084？km2. It has become the World’s largest man-made reservoir. The Dam generates up to 18,000？MW of hydroelectric power, establishes flood control along the river basin, and improves the economic stability of the upper reaches of the Yangtze through improved navigation capabilities [1]. The reservoir is operated in a seasonal mode: low water level (145？m) in summer and high water level (175？m) in winter. As the largest water conservation project in the world, the TGP has attracted worldwide attention. This attention has been not only for its comprehensive social and economic benefits but also for the potential impacts on the security of the natural environment, potential geological disasters, and impacts on biological diversity in the surrounding reservoir area. The
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