建库和气候变化对襄阳站径流的影响评估

Impact Assessment of Reservoir Construction and Climate Change on Runoff in Xiangyang Station

根据襄阳站日径流资料(1940—2012年),分别采用Mann-Kendell检验方法和RVA方法分析该站点的径流变化特征,认为襄阳站的年径流量呈现出一定程度的减少趋势,以夏、秋两季的减少最为明显,通过对月水文情势的变化评估认为径流年内分布的变化主要来自于丹江口水库的调丰补枯作用。进一步根据襄阳站以上流域的气象观测数据定性分析降水和气温的变化趋势,发现建坝后径流的演变与气候变化关系密切。在此基础上建立了径流与降水及气温的线性回归模型,通过对径流的模拟进一步验证了径流演变与当地气候变化密切相关,但由于人类活动影响的加剧,其相关性在1985年后有所减弱。

According to the daily runoff data of Xiangyang Station (1940-2012),Mann-Kendell test method and RVA method were used to analyze the runoff variation characteristics of the site.It was believed that the annual runoff of Xiangyang Station showed a certain degree of decreasing trend with the most obvious reduction in summer and autumn.Through the assessment of the change of monthly hydrological situation,it was believed that the variation of runoff distribution during the year mainly came from the adjustment and replenishment effect of Danjiangkou Reservoir.According to the meteorological observation data of the basin above the Xiangyang Station,the trend of rainfall and temperature was qualitatively analyzed.It was found that the evolution of runoff after dam construction was closely related to climate change.Based on this,a linear regression model of runoff,rainfall and temperature was established.It was further verified by the simulation of runoff that runoff evolution is closely related to local climate change,but its correlation had weakened after 1985 due to the intensification of human activities.