【摘要】 基于黄河源区1∶25万生态环境地质调查新获得的大量实际资料,通过分析和研究发现,黄河源区早更新世—中更新世处于走滑伸展的大陆动力学背景,在整体隆升中,形成断块山与拉分盆地,湖泊广布;晚更新世,大陆动力学机制过渡为挤压收缩,在整体抬升中,断块山显著崛起,湖盆萎缩、变形;全新世,大陆动力学环境反转为走滑挤压,持续隆升,黄河扩展源头到达本区,扎陵湖、鄂陵湖外泄,闭流盆地水环境转向开放。近代,特别是20世纪70年代以来,新构造活化与寒冻风化岩屑坡扩大、沙质荒漠化蔓延、湖泊和沼泽湿地萎缩、区域地下水位下降、源区黄河频繁断流、生态环境日益恶化响应关系密切。因此,新构造运动在黄河源区生态环境恶化中起主导作用,而其他因素则起到促进与加速的作用。更多还原

【Abstract】 Based on a wealth of data obtained in the 1∶250000 eco-environmental and geological surveys, the Yellow River source area was in a continental dynamic setting of strike-slip extension in the early-mid Pleistocene, and during its wholesale uplift there occurred block mountains and a pull-apart basin, where lakes were widespread. In the late Pleistocene the strike-slip extension graded to compressional-constriction. During the wholesale uplift, the block mountains rose markedly and the lake basin shrank and was deformed. In the Holocene, the dynamic environment was transformed into strike-slip compression and the source area was uplifted continuously and extended to the present area. The Gyaring Lake and Ngoring Lake overflowed and the hydrologic environment of the closed basin became open. In the Recent, especially since the 1970s, the neotectonic reactivation has been related to the expansion of the frost-weathered debris slope, spreading of sandy desertification, recession of lakes, swamps and wetlands, lowering of the regional groundwater level, repeated dry runs of the Yellow River in its source area and progressive deterioration of the eco-environment. Therefore neotectonic movement has played a dominant role in the eco-environmental deterioration in the source area of the Yellow River,while other factors have promoted and accelerated the deterioration.更多还原