ObjectiveAs the largest ecological construction project in China even in the world, Grain for Green Project exerts a series of important social, economic and ecological benefits. The region containing the upper and middle reaches of Yangtze River is the significant ecoregion of China, and key areas of Grain for Green Project implementation and monitoring ecological benefits, of which project area accounts for 33.60% of the national farmland area. To quantitative evaluate the ecological benefits of the region's Grain for Green Project comprehensively, systematically and scientifically, dividing the ecoregions was indispensable.

MethodFirst, we chose the map of Grain for Green Project implementation, mean annual precipitation, annual accumulated temperature above 10℃, important ecological functions of Grain for Green Project and geomorphic types as the data sources. Then, we selected geomorphic types, hydrothermal conditions and strength of soil and water conservation function of Grain for Green Project as three levels of regionalization indicators.

ResultFinally, we applied the geographic information system(GIS) space analysis to get the ecoregions. We got 4 class Ⅰ areas, 19 class Ⅱ areas and 31 class Ⅲ areas.

ConclusionBased on multiple indicators, which could characterize the features of Grain for Green Project in the region containing the upper and middle reaches of Yangtze River, ecoregions intuitively reflected the actual geographical regional rules. Meanwhile, it lays the foundation for ecological benefit monitoring and evaluation of the region's Grain for Green Project. This contributes to combine with its regionalization indicators when analyzed the ecological benefits of corresponding zones, using regionalization characteristics to verify the results of ecological benefit assessment.