Erosion and sediment control in China's Yellow River Basin
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THE Peoples Republic of China suffers some of the world's most severe erosion and sedimentation problems. Massive soil losses, particularly in the loess highlands of the country's northwestern region, produce enormous sediment loads and flooding on the lower Yellow River. These problems persist despite centuries of effort to reduce erosion.
A river suspended
The Yellow River, China's second longest (after the Yangtze), meanders for 3,000 miles (5,000 kilometers) through nine provinces, a watershed of about 260,000 square miles (680,000 square kilometers). The river originates in Tibet and features several unique reaches. In the upper reach, where the water is relatively clear, the river flows eastward from Tibet through mountains and grasslands, then turns northward, traversing the deserts and plains of Kansu and Ningsia Provinces. At that point, its course turns eastward again through Inner Mongolia, then southward through the Shansi and Shensi Provinces and the loess plateaus. It is on these loess plateaus that tremendous erosion occurs, delivering massive sediment loads to the river. The Yellow then turns eastward again and flows across the North China alluvial plain through Honan and Shantung Provinces, finally emptying its burden of sediment and …