Abstract:Dujiangyan Region is located on the western border mountains of Sichuan Basin, the transition belt from Qingzang Plateau to Chengdu plain. Its particular position makes it a part of the large scale, composite ecotone of China, and various geographical elements assemblage and transit here. Climatically,it lies in the middle subtropical zone,and the basic belt of vegetation is evergreen broad leaved forests. Because of the warm and moist climate and the rugged topography with alternating high mountains and ...