大通河流域径流变化及特征分析

根据大通河流域尕大滩和享堂两个水文站1952-2014年的逐月径流量资料,用不均匀性分析了径流量的年内分配情况,使用Mann-Kendall检验方法和Morlet小波变换对径流量突变和周期性分别进行了分析。结果表明:大通河流域的汛期主要为5-10月,尕大滩站和享堂站汛期径流量分别占全年的87. 81%和81. 9%。越向下游,大通河径流年内分配越均匀; 1991年之前,大通河上游和下游径流变化都呈下降趋势,1994年之后,上游尕大滩站径流量呈微弱的增加趋势,下游享堂站径流量呈快速下降趋势;上游尕大滩站径流量存在4、8、21a左右的周期震荡,下游的享堂站径流量则存在着3、6、31a左右的周期震荡; 1994年之前径流主要受气温和降水等气象的影响,之后人类活动占主导地位。

Analysis of runoff variation and characteristics in Datong River Basin

Based on the runoff data measured by Gadatan hydrological station and Xiangtang hydrological station in the Datong River Basin from 1952 to 2014, the distribution of runoff during the year was analyzed using unevenness, the mutation and periodicity of runoff in the basin were analyzed respectively by Mann-Kendall nonparametric test method and Morlet wavelet transform method. The results show that The flood season of the Datong River Basin was mainly from May to October, with a runoff proportion of 87.81% in Gadatan hydrological station and 81.9% in Xiangtang hydrological station. The upstream area presented a more uneven coefficient and a higher concentration rate than the downstream area. Before 1991, the runoff changes in the upper and lower reaches of the Datong River both showed a downward trend. After 1994, the flow of the Gadatan station showed a slight increase trend, and the runoff at the Xiangtang Station still showed a rapid downward trend. There are periodic oscillations around 4a, 8a, 21a in the Gadatan station, with 3a, 6a, and 31a occurred in the Xiangtang station. Before 1994, runoff was mainly affected by temperature and precipitation. After 1994, it was mainly affected by human activities.