近58a来洮河流域水沙演变特征与驱动力分析

Analysis on Characteristics Evolution and Driving Force of Water and Sediment Evolution in the Taohe River Basin in Recent 58 Years

采用洮河红旗水文站1956—2013年的水沙资料和流域降水资料,应用累计滤波器法、Mann-Kendall法、双累计曲线法等分析了洮河流域水沙量的时间序列变化特征,定量估算了降水变化和人类活动对年径流量和年输沙量的影响。结果表明:洮河流域年降水量、年径流深和年输沙量的变化倾向率分别为-4.6 mm/10 a、-13.8 mm/10 a、-444万t/10 a,年径流量及年输沙量在1986年左右发生了突变;就平均情况而言,降水和人类活动对径流的影响量分别约占径流减少总量的32.9%、67.1%,对输沙的影响量分别约占输沙减少总量的47.4%、52.6%,不同阶段的人类活动特征明显;随着流域内大规模人类活动的继续,水沙量的递减趋势在未来一定时期内将会持续。

Using the precipitation statistics and water and sediment data of Hongqi Hydrological Station on the Taohe River from 1956 to 2013 and applying the cumulative filter method,Mann-Kendall method,the double cumulative curve method etc,it aimed at the analysis of the time series variation of water and sediment in Taohe River basin and the quantitative estimation about effects of precipitation and human activities to the annual runoff and annual sediment discharge. The results show that the change trends of annual rainfall,annual runoff depth and annual sediment discharge of the river basin are -4. 6 mm/10 a,-13. 8 mm/10 a and -4. 44 million t/10 a respectively. Annual runoff and annual sediment discharge change greatly in about 1986. On average,the influence on water flow volume caused by precipitation and human activities accounts for 32. 9% and 67. 1% respectively of the total runoff decrease. Also,their impacts on the sediment transport amount account for 47. 4% and 52. 6%respectively of the total sediment reduction. Then,characteristics of human activities in different phases of the basin are very obvious. With the accumulation of human activities,the decreasing trend of water and sediment will be continued in a definite period of time in the future.