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水电部黄河水利委员会有关部门最近宣布,近年黄河泥沙显著减少,每年的输沙量比过去减少三至五亿吨。这不仅使黄河下游河床淤积速度减缓,而更重要的是这意味着黄河中上游黄土高原来沙量减少,人们在控制水土流失上取得了一定程度的成果。 专家们认为,黄河中上游干支流上修建的大型枢纽工程起了一定的拦沙作用,这是黄河中下游泥沙减少的一个重要因素,而黄土高原地带种树种草,恢复自然生态,减少土壤侵蚀和水土流失,则是黄河泥沙减少,实现黄河水变清的根本条件。 黄河上中游,从青海高原龙羊峡谷到河南省邙山,婉蜒在世界上最大的黄土高原地带,沿河两岸沟壑纵横,几百
Recently, the relevant departments of the Yellow River Conservancy Commission of the Ministry of Electricity and Mines announced that the sediment of the Yellow River has been significantly reduced in recent years and the annual sediment transport volume has dropped by 300 million to 500 million tons. This not only slowed down the sedimentation rate of the lower reaches of the Yellow River, but more importantly, it meant that the sediment yield of the Loess Plateau in the middle and upper reaches of the Yellow River decreased. People made some achievements in controlling soil erosion. Experts believe that large-scale hub projects built on the upper and middle reaches of the Yellow River play a role in blocking sediment, which is an important factor in sediment reduction in the middle and lower reaches of the Yellow River. In the Loess Plateau, planting grass, restoring natural ecology and reducing Soil erosion and soil erosion are the basic conditions for the reduction of sediment in the Yellow River and the realization of the clear water of the Yellow River. The upper and middle reaches of the Yellow River, from Longyang Canyon in Qinghai Plateau to Dangshan in Henan Province, wandering in the world’s largest loess plateau, ravines along the two sides of the river, hundreds