长江上游水土流失与防治对策研究

Soil and Water Loss and Its Controlling Countermeasures in the Upper Reaches of the Yangtze River

根据长江上游各省水土流失遥感分析资料、国土资源数据、农业区划和有关的水土流失研究成果 ,综合分析长江上游水土流失现状与特征 ,指出长江上游水土流失面积 4 9.63万km2 ,年平均土壤侵蚀量 2 1.79亿 t/ a,大部分地区属中、强度侵蚀区 ,平均土壤侵蚀模数 4 390t/ km2 .a。森林砍伐、植被破坏和坡耕地垦殖是造成水土流失加大的主要因素。防治对策应以小流域综合治理为核心 ,以坡耕地合理利用和保水保土措施为重点 。

According to the remote sensing information on the soil and water loss, the data of the land resource and agricultural region planning of the different provinces in the upper reaches of the Yangtze River and some relational studies, the present situation and the characteristics of soil and water loss are analyzed integrally. In the upper reaches of the Yangtze River there are 0.496 3 million square kilometers of the area of soil and water loss, 2.179 billion tons per annual of the soil erosion amount and 4 390 ton per square kilometer and per annual of the average soil erosion modulus. The majority of the soil erosion areas belong to a classification of the middle erosion and the intense erosion. It is confirmed that cutting down the forest, destroying the plant cover and cultivating on the slope land are the major factors increasing surface erosion. On the countermeasures to control soil and water loss in the upper reaches of the Yangtze River, carrying out the integrated conservation of the small basins as the kernel, and reasonable use of the slope land and the conservation farming measures as the key point are considered. And it is suggested that the project of plantting on the steep slope land as well as the project of preserving natural forests should be enhanced really.