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长江上游水土流失面积共35.2万平方公里,占总土地面积的35％。在35.2万平方公里中,轻度流失区占37.8％,中度流失区占31.5％,强度流失区占20.5％,极强度流失区占7.4％,剧烈流失区占2.8％。流失较严重的强度以上的流失面积占30.7％。五十年代至今,长江上游的水土流失经历了一个断续加剧和近几年来开始有所缓解的过程。总的结果是破坏大于治理,水土流失面积和流失量均有所增加。以输沙模数区分,每平方公里从数十吨到数千吨不等。直门达以上江源地区,每平方公里年输沙模数68吨为最小,白龙江中游立节至武都干流区间,年输沙模数4,437吨为最大。有的区域或个别年份的输沙模数更大。30年来,由于受多种因素的影响,长江上游有的河段和支流的沙量有增加,有的并未增加甚至有减小的趋势,更多的则是分时段有增有减,呈不规则的周期变化;往后也不会出现本质性的变化。当前的水土流失治理进度和成效,与艰巨的治理任务相比,显得十分缓慢而极不相称。近年来,这种一方治理、多方破坏的局面不改变,生态好转将永无尽期。
The area of soil erosion in the upper reaches of the Yangtze River totals 352,000 square kilometers, accounting for 35% of the total land area. Of the 352,000 square kilometers, 37.8% were moderately lost, 31.5% were moderately depleted, 20.5% were intensely depleted, 7.4% were very intense and 2.8% were violently depleted. The loss of more serious loss of area accounted for 30.7%. Since the 1950s, the soil erosion in the upper reaches of the Yangtze River has undergone a process of intermittent aggravating and starting to ease in recent years. The overall result is that destruction is greater than governance, with an increase in the area and loss of soil erosion. Distinguish between sediment transport modules, from tens of square kilometers per square kilometer to thousands of tons. Straight reach the above Jiangyuan area, the annual sediment transport module 68 tons per square kilometer is the smallest, the middle section of the Bailong River to Wudu mainstream section, the annual sand transport modulus of 4,437 tons is the largest. In some areas or individual years, the sediment transport modulus is even greater. In the past 30 years, due to a variety of factors, the amount of sand in some upper reaches of the Yangtze River and tributaries has increased, while others have not increased or even decreased. Mostly, it has been increased or decreased in different time periods Irregular cycle of change; the future will not be an essential change. The current progress and effectiveness of soil and water loss control, compared with the arduous task of governance, is very slow and extremely disproportionate. In recent years, the situation of such party governance and multilateral destruction has not changed, and the ecological improvement will never end.