气候变化对阿克苏河流域径流过程的影响

Climate Change and Its Effects on Runoff Process in the Headstream Areas of Aksu River Basin,Xinjiang

结合阿克苏河源流山区两气象站以及出山口两水文站近50 a的气象、水文实测资料,运用非参数Mann-Kendall单调趋势检验、突变检验、方差分析外推、R/S分析及周期性叠加趋势模型等方法,分析了阿克苏河源流区气候及径流变化的趋势和周期,并予以预测,探讨了气候变化对径流的影响量。结果表明:阿克苏河源流区气温、降水量及径流量皆呈显著增加趋势,且分别在1989、1985和1993年发生了显著的增多跃变;气候因子与径流量的Hurst指数均大于0.5,表明其未来仍将保持增加趋势,在2010—2016年径流量的相对最大值和最小值将分别为91.822×108 m3(2014年)和83.43×108 m3(2011年);阿克苏河径流量在整个时间序列存在25 a的准周期,但在突变前以17 a周期为主;气候变化使得阿克苏河源流在1994—2007年增加了224.97×108m3的来水量,年增加量的最大、最小值分别出现在2003年和2004年。

Based on the runoff data of two hydrological stations and the climate data of two meteorological stations during the period of approximate 50 years in the headstream areas of Aksu River Basin,the periodicity and trends of climate change and runoff were investigated by nonparametric test and an extrapolation method of variance analysis,and then the future change trend and runoff volumes of the annual runoff were predicted by the periodic trend superposition model and R/S analysis.In succession,the impact volumes of climate change on the annual runoff were separated from the observation values of the annual runoff in the Aksu River.the results showed that： the temperature,precipitation and annual runoff of Aksu River Basin increased significantly,and the mutations of which are at 1989,1985 and 1993,respectively;the Hurst coefficients of both climate factors and the annual runoff were bigger than 0.5,and indicated that they would still keep an increasing trend;the relative highest and lowest volumes of the annual runoff will be 91.822×108 m3 in 2014 and 83.430×108 m3 in 2011 during the period of 2010-2014;the annual runoff holds a quasi-25 years＇period from 1957 to 2007,but the primary period of 17 years was proved before shifting change;the increased volume of the annual runoff in the headstream due to climate change is 224.97×108 m3 after shifting change,and the highest value and lowest value of the affecting volume are in 2003 and 2004,respectively.