1951—2016年黄羊河流域径流变化特征及影响因素分析

Characteristics of runoff variation in the Huangyang River basin from 1951 to 2016

利用1951-2016年黄羊河水库水文数据对流域年内、年际径流分配变化特征进行分析,并探讨了影响本区径流变化的因素,定量评估了气候和人类活动对径流变化的贡献.结果表明:黄羊河流域年内径流月际分配不均匀,主要集中在7-9月,占全年49.08%;65a来黄羊河流域以平水年为主,其中,50年代为特丰年,90年代和21世纪00年代为偏枯年;黄羊河流域径流变差系数Cv值为0.25,年极值比为3.12,表明了黄羊河流域径流的多年变化是相对稳定的.黄羊河流域径流的年内变化与降水的变化具有很好的同步性,但径流多年变化与降水长期变化趋势出现不一致,说明黄羊河流域径流除了受气候条件的影响外,人类活动也对其产生了影响.1966-2016年与1951-1965年时段相比,黄羊河流域气候变化与人类活动对径流减少的贡献率分别为46.24%和53.76%.

Based on the hydrological data of Huangyanghe Reservoir from 1951 to 2016,this paper analyzes the variation characteristics of interannual runoff distribution in the basin,discusses the factors that affect the variation of runoff in this area,and quantitatively evaluates the contribution of climate and human activities to runoff changes.The results show that the monthly distribution of runoff in Huangyang River basin is uneven,mainly centralized from July so September,accounting for 49.08% of the year and 65 years,in which 1950 sare especially abundant years,1990 sand 2000 s are mostly dry years.The runoff variation coefficient(Cv)of Huangyang River basin is 0.25 and the annual extreme ratio is 3.12,which indicates that the runoff variation in Huangyang River basin is relatively stable.The annual variation of runoff and the variation of precipitation in Huangyang River basin have a good synchronism,but the variation of runoff over many years is not consistent with the trend of long-term change of precipitation,which indicates that the runoff of Huangyang River basin is affected by the climatic conditions.Compared with 1951-1965,climate change and human activities contributed 46.24%and 53.76%to runoff reduction in Huangyang River basin,respectively.