窟野河流域河川基流变化及其驱动因素分析

Based on the daily runoff data from 1956 to 2012 at Wenjiachuan Hydrological Station in the Kuye River Basin and climate data, etc., by comparing the base flow processes segmented by nine methods in four categories, namely the Recursive Digital Filtering Method (RF method), Digital Filtering Method, Smoothing Minimum Method and HYSEP method, as well as the statistical characteristics of the base flow index and the segmentation effect errors, a suitable segmentation method is determined; the difference-product curve method and the moving t -test method are used to determine and test the base flow mutation years; the double cumulative curve method is used to calculate the contribution rates of climate factors and human activities respectively. The results show that it is more reliable to use the F1 method for base flow segmentation. The base flow not only shows a continuous decreasing trend, but also the mutation years 1980 and 1996 are inconsistent with the climate mutation points. Taking the mutation years as the boundary, the time series is divided into three stages. Compared with the base period, the contribution rates of climate and human activities in the second and third stages are 7.72%, 92.28% and 15.73%, 4.27% respectively. In the 21st century, human activities have always been the main factor affecting the base flow, and the impact of climate change on the base flow shows an increasing trend.

基于窟野河流域温家川水文站1956~2012年的日径流资料以及气候等数据，通过比较递归数字滤波法(RF法)、数字滤波法、平滑最小值法与HYSEP法四类共九种方法分割的基流过程、基流指数统计特征与分割效果误差，确定出适合的分割方法；采用差积曲线法与滑动t检验法确定并检验基流突变年份；采用双累积曲线法分别计算气候因素与人类活动的贡献率。结果表明：选用F1法进行基流分割更为可靠。基流不仅呈现出持续减少的趋势，且突变年份1980年和1996年与气候突变点不一致，以突变年为界将时间序列分为三个阶段。与基准期相比，第二、三阶段气候和人类活动的贡献率分别为7.72%、92.28%和15.73%、4.27%。进入21世纪，人类活动始终是影响基流的主要因素，气候变化对基流的影响呈现出日益增长的趋势。