Abstract: In this paper, the impacts of three gorge project on agricultural ecosystem in Changjiang River Basin were studled. These impacts fall into two categories. The first is suddenchanging impact including land inundating, people migration and increasing pressure on alway-weakened ecosystem and environment of reservoir area. The second is slow-changing impact with variation of hydrological condition, namely, increasing trend of potential gleization and bogging of paddy field in middle and lower reaches and salinization in delta area. To improve ecosystem and land bearing capability in Changjiang River Basin, some measures should be taken such as closing hillsides to facilitate forestation, preserving water and soil, reasonably arranging the proportion of land for crops and forest, strengthening amelioration of water and soil and preventing soil gleization, bogging and salinization.

Key words: Three gorge project, Agricultural ecosystem, Soil erosion, Soil bogging, Soil Salinization