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三川河流域自1983年列入全国八大重点治理区后,至1992年底止,10年新增治理面积1129km~2,流域累计治理程度达到57.6％。采用水文法与水保法分析该流域重点治理以来的减沙效益,前者的分析结果是,重点治理期间的年均输沙量较重点治理前减少59.03％,每毫米汛期降雨所产生的输沙量分别比1957～1972年、1957～1982年减少61.30％和52.23％;后者的分析结果是年均输沙量分别比1957～1972年、1957～1982年减少44.26％和55.18％。考虑到降雨变化对水文法分析产沙的影响,故10年重点治理期间较重点治理前多年平均输沙量年均减少约为50.0％。
Since 1983, Sanchuan River Basin was included in the eight key areas of governance, until the end of 1992, 10 years new governance area of 1129km ~ 2, the basin has reached a cumulative degree of governance of 57.6%. The results of the former analysis indicate that the average annual sediment discharge during the key governance period is reduced by 59.03% compared with that before the pre-treatment, and the sediment discharge caused by precipitation per mm flood season Respectively, decreased by 61.30% and 52.23% respectively from 1957 to 1972 and from 1957 to 1982; the latter analysis showed that the average annual sediment transport decreased by 44.26% and 55.18% respectively from 1957 to 1972, and from 1957 to 1982. Taking into account the impact of rainfall changes on hydrological analysis of sediment yield, the annual average sediment load decreased by about 50.0% over the previous 10 years.