气候变化和人类活动对武江流域年径流及最大日流量影响的定量分析

针对气候变化与人类活动对流域年径流及最大日流量变化影响的定量识别问题,以华南湿润区武江流域为例,分别采用HIMS（Hydro-Informatic Modeling System）模型和敏感性系数法,从日和年尺度定量模拟和评估气候变化与人类活动对流域年最大日流量和径流变化的影响过程及贡献率。结果表明：HIMS模型在武江流域适用性良好,日尺度模型率定期和验证期的纳西效率系数分别为0.85和0.77,水量平衡误差绝对值分别为3.1%和3.3%;两种方法均表明气候变化是引起流域年径流量增加的主要因素,人类活动导致了流域径流量的减少,但贡献率较小。气候变化与人类活动导致了流域年最大日流量的增加,气候变化对年最大日流量增加的贡献率为94%,而人类活动的贡献率则为6%。相较于年均径流量,气候变化对年最大日流量的影响更为显著。

Quantitative Analysis of the Impacts of Climate Change and Human Activities on Annual and Maximum Daily Runoff in the Wujiang River Basin

Focusing on the quantitative identification of the impacts of climate change and human activities on annual and maximum daily runoff at a basin scale, taking the Wujiang River Basin, South China for instance, this paper simulated and quantitatively evaluated the impacts of climate change and human activities on runoff and their contribution ratios to runoff at daily and annual scales by using the HIMS model and elastic coefficient method. The results showed that, the HIMS model performed well in the Wujiang River Basin at daily scale. The Nash-Sutcliffe coefficients are 0.85 and 0.77, and the absolute values of water balance errors are 3.1% and 3.3% respectively in calibration and validation periods. The results obtained by the HIMS model and the elastic coefficient method indicated that climate change is the dominat factor that leads to the increase of annual runoff and human activities cause the runoff decrease while its contribution ratio is smaller compared to that of climate change. The annual maximum daily runoff showed an upward trend due to climate change and human activities. The contribution ratios of climate change and human activities are 94% and 6%, respectively. Climate change has greater impact on annual maximum daily runoff than that on annual average runoff.