晚更新世以来的季风变化对晋陕蒙接壤区现代侵蚀的影响

黄土高原晚更新世末次冰期时期,冬季风强盛,马兰黄土堆积;全新世以来的间冰期时期,夏季风强盛,降水较丰,侵蚀强烈。晚更新世以来的中国东部海岸线40°N 一带变化最大,同纬度晋陕蒙接壤区是黄土高原季风气候变化最剧烈的地区,致使该区成为黄土高原沙黄土区中现代降水最多的地区。沙黄土和较多降水的组合,使晋陕蒙接壤区成为黄土高原现代侵蚀最剧烈的地区。

THE INFLUENCE OF MONSOON CLIMATE CHANGES SINCE LATE PLEISTOCENE ON CURRENT EROSION IN THE JINSHANMEN CONTIGUOUS REGION OF THE LOESS PLATEAU

Malan Loess,the major eroding surface layer in the Loess Plateau,was deposited during the last glacial period of late Pleistocene,at that time climate in the plateau was strongly influenced by winter monsoon. During the last interglacial period of Holocene, climate was strongly influenced by summer monsoon,precipitation was much higher than that in the last glacial period, and heavy rainfall caused severe erosion in the plateau. Due to greatest changes of coast lines in East China at latitude of38°,climate in the Jinshanmen contiguous region at same latitude has been the most changeable in the plateau,The region had the highest precipitation in the coarse Malan Loess zone of the plateau in Holocene. Owing to the combination of erodible surface layer and high precipitation,current soil erosion in the Jinshanmen contiguous region is the severest in the Loess Plateau.