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’98长江洪水使人们愈来愈深刻地认识到,长江上中游生态破坏、水土流失是造成这次抗洪形势严峻的重要原因之一。长江上中游生态系统的重建,特别是林业建设提到了重要议事日程。当务之急是要保护现有的森林资源不再遭到破坏;另一方面要加快促使水土流失最严重的25度以上的陡坡耕地还林还牧。坡耕地水土流失的严重性和治理的紧迫性坡耕地水土流失是现代土壤侵蚀最突出的问题,也是世界性的问题。据联合国环境署和粮农组织调查,地球2/3的陆地曾
’98 The floods in the Yangtze River have made people realize more and more profoundly that the ecological destruction and soil erosion in the upper and middle reaches of the Yangtze River is one of the important causes of this severe flood fighting situation. The reconstruction of the upper and middle reaches of the Yangtze River ecosystem, especially forestry construction, referred to the important agenda. The top priority is to protect the existing forest resources from being destroyed. On the other hand, it is necessary to speed up the return of more than 25 degrees of steep slopes to forests and grazing to promote the most serious soil erosion. The severity of soil and water loss and the urgency of management in sloping arable land Soil and water loss in sloping arable land is the most prominent problem of modern soil erosion and also a worldwide problem. According to a survey conducted by the United Nations Environment Program and FAO, two thirds of Earth’s land was once