1963—2014年呼伦湖流域降水对径流量变化的影响

Impacts of Precipitation on Runoff Yield of Hulun Lake Basin During 1963—2014

[目的]分析呼伦湖流域降水对径流量变化的影响,为流域水资源可持续利用和高效配置提供可参考依据。[方法]根据呼伦湖流域阿拉坦额莫水文站1963—2014年水文气象数据,采用累积距平法和Mann-Kendall法结合对呼伦湖流域50a径流和降雨年际变化趋势进行分析,确定出2个拐点年份,用累积量斜率变化率比较法评估降水对呼伦湖流域径流变化的影响。[结果]拐点年出现在1972,1999年,以初始研究阶段T_1(1963—1972年)为基准期,不考虑潜在蒸散量变化的影响,T_2(1973—1999年)和T_3(2000—2014年)时期的降水量减少对于径流量减少的贡献率分别为0,40.70%。[结论]21世纪年代以后降水与径流明显偏少,年径流量与降水量有很好的线性相关关系,降水减少是径流减少的主要原因。近年来人口增多,畜牧业发展昌盛,也对径流有一定的影响。

[Objective] The effect of precipitation on runoff sequence of Hulun Lake during 1963--2014 was analyzed to provide reference for sustainable utilization and efficient configuration of river basin water resources. [-Methods] Based on the observed data of Hulu Lake Station during 1963--2014, we used the methods of cumulative anomaly and Mann-Kendall to illustrate the change trend of precipitation and runoff and to demonstrate change ratio of cumulative quantity slope. We calculated quantitatively the contribution rate of the precipitation and human activities on runoff. [-Results] Two inflection points occurred in 1972 and 1999. According to the two points, the cumulating process of the variables was divided into three periods, 1963-- 1972（T1）, 1973--1999 （T2） and 2000--2014（T3）. Taking T1 as the base referred period, the contribution rates of the precipitation to the decrease of runoff were 0 in T2, and 40.7% in T3. [Conclusion] Since the twenty-first century, the precipitation and runoff were obviously less. Annual runoff and precipitation had a good linear correlation. And the precipitation reduction was the main reason for the decrease of runoff. In recent years, population increased and animal husbandry development have their certain influence yet.