近期黄河潼关以上地区淤地坝拦沙量初步分析

Analysis on the Sediment Retaining Amount by Warping Dams Above Tongguan Section of the Yellow River in Recent Years

进入21世纪以来,黄河泥沙显著减少,潼关水文站实测输沙量由1919—1959年的平均15.92亿t减少到2000—2012年的平均2.76亿t。黄河流域已建淤地坝58 099座,分布在黄土高原的千沟万壑,具有显著的拦沙减蚀作用。依据第一次全国水利普查、水利部淤地坝大检查等基础数据,初步分析了2000—2012年黄河潼关以上地区淤地坝拦沙减蚀作用。结果表明:(1)2000—2012年黄河潼关以上淤地坝年均拦沙减蚀量为4.50亿t,其中年均拦沙量为3.75亿t、减蚀量为0.75亿t。同期潼关以上地区5 520座骨干坝的年均拦沙减蚀量为2.05亿t,其中年均拦沙量为1.71亿t、减蚀量为0.34亿t;50 935座中小型淤地坝的年均拦沙减蚀量为2.45亿t,其中年均拦沙量为2.04亿t、减蚀量为0.41亿t。(2)淤地坝拦沙减蚀作用对2000—2012年黄河泥沙减少的贡献率为34%。

Since the beginning of the 21 stcentury,the sediment of the Yellow River has been decreased significantly and the measured sediment in Tongguan Hydrometric Station has been decreased from 1592 million tons per year during 1919-1959 to 276 million tons per year during 2000-2012. There are 58,099 warping dams in the Yellow River basin distributed in the thousands of gullies of the Loess Plateau,playing remarkable function of retaining sediment and erosion reduction. Based on the basic data of the first national water resources survey results and statistical data from the warping dam by Ministry of Water Resources,the effects of the warping dams for conserving soil and water above Tongguan reaches of the Yellow River during 2000 to 2012 have been primarily analyzed. The results show that the conserving soil and water above Tongguan reaches of the Yellow River per year during 2000 to 2012 is 450 million tons,including 375 million tons of the sediment retaining amount per year and 75 million tons of the soil reduction amount per year. During the corresponding period,the conserving soil and water of the 5,520 warping dams above Tongguan reaches of the Yellow River per year is 205 million tons,including 171 million tons of the sediment retaining amount per year and 34 million tons of the soil reduction amount per year and the conserving soil and water of the 50,935 small and medium-sized warping dams is 245 million tons,including 204 million tons of the sediment retaining amount per year and41 million tons of the soil reduction amount per year. The results also indicate that the contribution rate of the conserving soil and water to the sediment reduction of the Yellow River per year during 2000 to 2012 is 34 percent.