Vicissitude of Mu Us Desert Recorded by Stratigraphical Characteristics of Disaogouwan Section in Southern Erdos Plateau

The vicissitude of the Mu Us Desert in North China is obviously influenced by the global change,especially by the East Asia summer monsoon change.Research on sediment composition,granularity parameter,stratigraphical structure,and on regional climate change and sporo-pollen assemblage is conducted in this study.The research result divides the process of the Mu Us Desert evolution into the following phases: ①the late period of Middle Pleistocene Series: the desert area was relatively small,the climate was warm semi-arid to warm semi-humid,and the landscape was desert steppe or shrub steppe;②the late period of Middle Pleistocene: the desert was stable,the climate frequently fluctuated between cold-arid and cold-semiarid,and the natural landscape varied among desert,desert steppe and steppe,in which river and pond appeared;③the early period of Late Pleistocene: the desert was stable,the climate was warm semi-humid to warm semi-arid,the natural landscape experienced a series change of forest steppe,shrub steppe,steppe and desert steppe;④the late period of Late Pleistocene: the desert extended,the climate was cold and arid,and the landscape was predominated by desert and desert steppe,simultaneously appeared with steppe and shrub steppe;the Holocene: the climate and the desert extent frequently changed,the landscape varied among desert,desert steppe,steppe and opening forest steppe.