Abstract:

The evolution of the Ulan Buh Desert presented a multi-stage and repeated pattern， which was characterized by the overlapping of lacustrine layer and aeolian sand layer. A paleolake developed at 120-90 ka， 60-50 ka， 40-20 ka， and 8-5.5 ka， while the deserts expanded at 150-130 ka， 90-60 ka， 50-40 ka， 20-10 ka， and 5.5 ka-modern period. Due to the different spatiotemporal scale， tectonic activity， climate change and Yellow River change were the main reasons for the environmental evolution of the Ulan Buh Desert since the late Pleistocene. The Ulan Buh Desert had become a key area in northern China due to its drastic environmental changes. The further expansion of the desert was exacerbated by human activity in the late Holocene. Future research needs to accurately refine scientific issues and enrich spatiotemporal scale and scientific methods. These provide an accurate understanding of the complex process of desertification. It will play a key role in addressing climate change， promoting ecological progress and promoting sustainable regional development.

Key words: drought region, environmental evolution, spatiotemporal scale, driver mechanism