气候变化和人类活动对丹江口入库径流的影响及评估

科学估算气候变化和人类活动对河川径流的影响,可以更为合理地规划利用地球水资源。针对丹江口水库入库径流的减少问题,分别采用Mann-Kendall方法和Pettitt检验,对1960~2012年间丹江口水库入库径流的年际和年内变化趋势进行了分析,并与同时期汉江上游20个地面观测站的降水、气温的年际和年内演化趋势进行了比较,从气候变化和人类活动影响的两个方面分析了入库径流减少的原因。在此基础上,利用气候弹性模型分别估算了气候变化和人类活动对径流的影响度。结果表明:近年来丹江口入库径流的减少主要受春季和秋季径流减少的影响,在春季径流的减少总量中,气候变化的贡献度为67%,人类活动为33%;秋季径流的减少总量中,气候变化的贡献度为88%,人类活动为12%。气候变化是导致丹江口入库径流减少的主要原因。

QUANTITATIVE ASSESSMENT OF CLIMATE CHANGE AND HUMAN ACTIVITY IMPACT ON INFLOW DECREASE OF DANJIANGKOU RESERVOIR

Quantitative evaluation the effects of climate change and human activities on river flow is of great importance for water resource management and utilization. As the water source of China's South-to-North Water Transfer Project in the middle line, Danjiangkou reservoir's function may be severely affected by the decrease of runoff into the reservoir. In this paper, runoff data from 1960 to 2012 and climatic data from 20 meteorological stations of Hanjiang River basin between 1960 and 2012 were used to analyze and compare the changing trends of runoff, precipitation and temperature by using the Mann-Kendall test method and the Pettitt test method, aiming at finding reasons for the decrease of reservoir inflow. Then, the climate elasticity model is adopted to estimate the degree of climate change effect on flow decrease. Our results indicated that climate change was the dominant reason for the inflow decrease in spring and autumn. In spring, climate change accounted for 67% of the decrease of reservoir inflow and human activities accounted for 33%; in autumn, climate change accounted for 88% of inflow decrease and human activities accounted for 12%.