新构造运动对黄土高原环境变迁的影响

新构造运动是黄土高原区域环境变迁的主导性因素。2．5Ma以来青藏高原的阶段性强烈隆升，导致了东亚季风气候的形成和加强，黄土高原乃至整个西北地区气候倾向干旱化趋势演化。黄土高原及其周边地区的阶段性隆升或沉隆与气候演化的共同作用，导致了黄土堆积沉积的跳跃式阶段性扩展。黄土高原地貌演化可以黄河水系的诞生为界限（1．67－1．43MaB.P)划分为二个阶段：古湖泊低地阶段和高原河流阶段。

The Impact of Neotectonics on the Environmental Evolution and Soil Erosion of Loess Plateau

Neotectonics was the dominant factor of the environmental evolution of Loess Plateau. Since 2.5 MaB.P. , because of the periodical uplift of Qinghai-Xizang Plateau, the monsoon climate was developed and gradually strengthened, and correspondingly the climate of Loess Plateau and even the whole west-northern region of China have correspondingly been tending to become more and more arid. Since 2.5 MaB.P., together with the climatic evolution, the periodical uplift or subsidence of Loess Plateau and its around area induced the bouncing and periodical enlargement of the deposition of loess. The landform of Loess Plateau may be divided into two stages: ancient lake low-lying land stages and plateau-river stage.