气候变化对太子河流域水资源影响研究

Study on Impact of Climate Change on Water Resources in Taizi River Basin

根据太子河流域的水文特征与水资源特点,利用SWAT模型揭示了流域水资源受气候变化的影响作用。为解决1:25万DEM数字高程模型提取水系过程存在的支流位置、形状偏差较大的问题,加载运行了精度为1:400万电子河网,通过分析模型参数敏感性校准、验证了模型的计算精度与可靠性,然后以1976-2017年太子河气象资料为依据,模拟分析了流域水资源受气候变化的影响作用。研究表明:2009-2012年校准期R2=0.94、Nash系数Ens=0.96,2013-2016年验证期R2=0.88、Nash系数Ens=0.82,在模拟分析流域水资源月径流变化过程中该模型具有较高的精度与可靠性;太子河中下游降水量与年内地表径流、基流变化保持较好的一致性,该区域的水量输出项以蒸散发为主,相对于降水过程地表径流存在一定的滞后性,滞后期为2个月,基流量约为地表径流的1/2。

According to the characteristics of hydrology and water resources of the Taizi river basin,SWAT model was used to discover the impact of climate change on water resources.In order to solve the problems that the location and shape deviation of tributaries are large in water extraction process of 1∶250,000 digital elevation model,the loading runs with an accuracy of 1∶400,0000 electric river network,by analyzing the sensitivity of model parameters,to check the calculation accuracy and reliability of the model,then taking the meteorological information of the Taizi river basin from 1976 to 2017 as the accordance,the impact of climate change on water resources of the river basin was simulated and analyzed.The results show that:R2=0.94,Nash coefficient Ens=0.96 during the calibration period from 2009 to2012,R2=0.88,Nash coefficient Ens=0.82 during the verification period from 2013 to 2016,this model has high accuracy and reliability in the process of simulating and analyzing monthly runoff change of water resources;the precipitation of middle and lower reaches of the Taizi river is consistent well with the annual change of surface runoff and base flow,the output term of water volume in this region is mainly evapotranspiration,compared with the surface runoff,the precipitation process is a certain lag,the lag period is two months,and base flow volume is 1/2 of the surface runoff.