Changes of vegetation in the sandy desertification process of grassland in Yanchi,Ningxia

摘要

@@Introduction Yanchi county,locates at the southwest fringe of Mu Us sandy land,and is an ecotone comprising sandy land through to desert steppe and to steppe.Over the recent decades,Yanchi has suffered severe sandy desertification.The distinct vegetation conditions between sandy grasslands at different desertification levels have resulted from a considerable difference in intensity of wind erosion.The objective of this study is to explore the changes of vegetation characteristics among different desertification degrees.