1956-2010年淮河流域极端径流的时空变化及统计模拟(英文)

Based on the daily runoff data from 20 hydrological stations above the Bengbu Sluice in the Huaihe River Basin during 1956-2010, run test, trend test and Mann-Kendall test are used to analyze the variation trend of annual maximum runoff series. The annual maximum series (AM) and peaks over threshold series (POT) are selected to describe the extreme distributions of generalized extreme value distribution (GEV) and generalized Pareto distribution (GPD). Temporal and spatial variations of extreme runoff in the Huaihe River Basin are analyzed. The results show that during the period 1956-2010 in the Huaihe River Basin, annual maximum runoff at 10 stations have a decreasing trend, while the other 10 stations have an unobvious increasing trend. The maximum runoff events almost occurred in the flood period during the 1960s and 1970s. The extreme runoff events in the Huaihe River Basin mainly occurred in the mainstream of the Huaihe River, Huainan mountainous areas, and Funiu mountainous areas. Through Kolmogorov-Smirnov test, GEV and GPD distributions can be well fitted with AM and POT series respectively. Percentile value method, mean excess plot method and certain numbers of peaks over threshold method are used to select threshold, and it is found that percentile value method is the best of all for extreme runoff in the Huaihe River Basin.     

金沙江下游及三峡段水文气象因子演变与响应的分析

对金沙江下游及三峡段3个水文站1954~2008年径流序列和2个气象站1951~2008年降雨、气温序列运用滑动平均法和Mann-Kendall法进行趋势性检验,利用有序聚类法、均值检验法分析突变性及小波分析法进行周期性诊断,并应用Pearson法对径流、降雨和气温的相关关系进行研究。研究表明:(1)研究区径流量的年内分配不均匀性和年际变化不显著。(2)金沙江下游段屏山站的径流量呈上升趋势,并在1997年发生突变,但该区域宜宾站的降雨量呈下降趋势并在1991年发生突变;三峡段寸滩站和宜昌站的径流量呈下降趋势,分别在1968年和2005年发生突变,同时该区域沙坪坝站的降雨量呈上升趋势并在1961年和1995年发生突变。(3)径流和降雨时间序列都存在小于10a的主周期以及20a以上的次周期。(4)各水文站夏季径流量受同期降雨量和同期气温的共同影响,而秋季径流量受前期气温的影响最大。