关键词: 15ka以来, 毛乌素沙地, 气候变化, 沙漠演化

Abstract: The transitional area between Mu Us Desert and Loess Plateau is typically sensitive to global changes, so this area is ideal for research of climate change and desert evolution. Through analysis on sediments in Sandaogou section that located on desert-loess transitional area, in combination with 14C dating and optically stimulated luminescence dating and the former researches, the characteristics of climate change and desert evolution in Mu Us Desert since15 ka BP are discussed: (1)Before 15 ka BP, Mu Us Desert experienced the late Last Glacial Maximum, the climate there was dry and cold, the winter monsoon was stronger and the deserts expanded. (2)15~6.33 ka BP, the climate was warmer and wind was weaker than before, but sand dunes were moving types. There were some warm-wet events during this period. (3)6.33~3.5 ka BP, winter monsoon was weaker and summer monsoon was stronger than before. The climate was warm and wet, and the deserts area contracted. But there also had some fluctuations of dry-cold climate, especially the cooling event occurred in about 5 ka BP, which was clearly recorded in Mu Us Desert. (4)Since 3.5 ka BP, the winter monsoon became stronger again and the summer monsoon was weaker, the climate was dry and cold, and aeolian activities became stronger.

Key words: since 15 ka BP, Mu Us Desert, climate change, desert evolution