滴哨沟湾地层沉积特征记录的毛乌素沙漠变迁

 毛乌素沙漠的盛衰变化明显地受到全球变化特别是东亚夏季风变化的影响。根据毛乌素沙漠东南缘萨拉乌苏河流域滴哨沟湾地层沉积物的物质组成、粒度参数等,结合孢粉研究结果,将沙漠演化过程划分为若干阶段：中更新世晚期沙漠萎缩期,气候温暖半干旱-半湿润,沙漠缩小,为森林草原或灌丛草原;中更新世晚期沙漠稳定期,气候在寒冷干旱-半干旱间波动频繁,自然景观在荒漠、荒漠草原与干草原间变化,并有河流和小湖存在;晚更新世早期沙漠固定期,气候温暖半湿润至半干旱,期间自然景观经历了森林草原、灌丛草原、草原、荒漠草原多种变化;晚更新世晚期沙漠扩张期,气候干旱寒冷,自然景观以荒漠和荒漠草原为主,同时也有草原乃至灌丛草原出现;全新世沙漠频繁变化期,气候变化频繁,沙漠出现多次盛衰变化,自然景观在荒漠、荒漠草原、草原、疏林草原间变化。

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.