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我国水患频繁的一个重要原因,是国土生态环境遭到严重破坏。长江流域几大淡水湖的泥沙淤积不断增加,泥沙的60%以上来自中游开垦的坡地,仅四川、重庆每年流入长江的泥沙就达5.33亿吨。特别是1998年我国遭受罕见洪水灾害,除了气候异常,降雨集中原因外,也与生态环境遭受严重破坏有关系。同样,由于黄河上中游过度垦荒、放牧,土地荒漠化不断扩大.沙化土地每年净增2460平方公里。特大沙尘暴等自然灾害天气时有发生,并且波及的范围愈来愈广,造成的损失愈来愈重。保护和改善生态环境是我国实施
An important reason for the frequent floods in our country is the serious damage to the ecological environment of the country. Sediment deposition in several major freshwater lakes in the Yangtze River Basin has been increasing. Over 60% of the sediment comes from reclaimed slopes in the middle reaches of the Yangtze River. Sediment inflows to the Yangtze River in Sichuan and Chongqing alone each year have amounted to 533 million tons. In particular, in 1998, China experienced rare flood disasters, in addition to the abnormal climate and the reasons for rainfall concentration, but also with the serious damage to the ecological environment. Similarly, due to over-reclamation, grazing and land desertification in the upper and middle reaches of the Yellow River, the desertified land has been net increased by 2,460 square kilometers per year. Natural disasters such as large dust storms happen from time to time, and the scope of the spread is getting wider and wider, causing more and more losses. To protect and improve the ecological environment is our country’s implementation