摘要
The desert/loess boundary belt is the transitional region between desert and loess, where aeolian sand and loess interlock in space and alternate in time. It, being seriously unstable in space-time, sensitive to climatic changes and with fragile ecological environment, is an ideal region for studying the global climate change. There are deposi-tional sequences of paleosol with sub-horizontal interbedded aeolian sand and loess, and the stratigraphical evidences show that there widely exist 3-4 layers paleosol in sand lands of northeastern China, 4-5 layers in Mu Us Sandy Land and Hunshandake Sandy Land, more than 4 layers in the Qinghai Lake region and the Gonghe Basin of Qinghai Province during the Holocene. These indicate that the desert has experienced several times of extending and compacting, along with which the desert/loess boundary belt vibrated. It possesses good coherence with global climate change and eustasy. The coherence shows that the monsoon change in East Asia is the primary driving
The desert/loess boundary belt is the transitional region between desert and loess, where aeolian sand and loess interlock in space and alternate in time. It, being seriously unstable in space-time, sensitive to climatic changes and with fragile ecological environment, is an ideal region for studying the global climate change. There are depositional sequences of paleosol with sub-horizontal interbedded aeolian sand and loess, and the stratigraphical evidences show that there widely exist 3–4 layers paleosol in sand lands of northeastern China, 4–5 layers in Mu Us Sandy Land and Hunshandake Sandy Land, more than 4 layers in the Qinghai Lake region and the Gonghe Basin of Qinghai Province during the Holocene. These indicate that the desert has experienced several times of extending and compacting, along with which the desert/loess boundary belt vibrated. It possesses good coherence with global climate change and eustasy. The coherence shows that the monsoon change in East Asia is the primary driving factor for the swing of desert/loess boundary belt. Besides, human influence constantly intensified the swing of the belt, especially in the south of Mu Us Sandy Land during the 2000–3000 aBP.
基金
This work was supported by the Innovation Project of Cold and Arid Regions Environmental and Engineering Research Institute, the Chinese Academy of Sciences (CAS) (Grant No. 210070)
the State Key Basic Research Development Project (Grant No. G199904340