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长江上游各支流区域内森林植被遭到破坏,水土流失加剧,致使长江含沙量增加,已经引起人们极大的关注。 森林植被的破坏,水土流失的加剧,主要由于开荒、滥砍滥伐、工矿资源的开发和道路工程的兴建等等。据林业部门调查,西南林区的被复率已由28％下降到13％。纵观破坏植
Forest vegetation in all tributaries of the upper reaches of the Yangtze River has been destroyed, soil erosion has been aggravating, resulting in an increase of sediment concentration in the Yangtze River. It has drawn great attention. The destruction of forest vegetation and the aggravation of soil and water loss are mainly caused by land reclamation, deforestation, the development of industrial and mining resources and the construction of road works. According to a survey conducted by the forestry department, the recovery rate in the southwest forest area has dropped from 28% to 13%. Throughout destruction of plants