黄土高原第四纪期间水土流失的地质记录和基本规律

The Records of Quaternary Soil Erosion in the Loess Plateau

黄土高原保存有许多第四纪期间水土流失的地质记录,这些记录表明,50 万年以来,黄土高原至少有 5 个水土流失十分强烈的时期,它们分别出现在 0.70～0.50M aB.P、0.2～0.25M aB.P、0.14～0.08MaB.P、0.01～0.015MaB.P和 0.006～0.002MaB.P 等气候温暖湿润的阶段。

There are lot of records of Quaternary erosion(gully erosion,slope erosion and debris flow)in the Loess Plateau.By field survey and data analysis,the main 5 stages of strong soil erosion happened at 0.70~0.50MaB.P.,0.2~0.25MaB.P.,0.14~0.08MaB.P.,0.01~0.015MaB.P.and 0.006~0.002MaB.P..The correlation between the records of soil erosion and climate change since the fifth paleosoil layer shown that soil erosion happened at humid temperate climate. In addition,precipitation and surface runoff were much higher in the humid temperate stages,affecting the stability of the underlying loess with vegetation.This resulted in the onset of erosion and the development of gullying.