河南省主要河道径流年内分配规律探讨

基于河南省四大流域代表性河道控制站1950~2011年月径流序列,采用集中度Cd、集中期Cp、不均匀系数Cv等多指标分析方法,分析了各站径流年内分配特征和规律,并采用M-K趋势分析法,研究各站月径流序列变化趋势。结果表明:河南省自南向北各河流,月径流集中度和不均匀度有减小趋势,径流重心也逐次后移,且存在两个跳跃区间,黄河、伊洛河、卫河Cd、Cv处于低值区间,淮河干流及淮南支流、洪汝河、沙颍河、唐白河Cd、Cv处于高值区。1980年以后,各站径流集中度降低、集中期延后、不均匀系数变小。北部和西北部河流月径流呈显著减小趋势;南部河流4、5月份径流量有显著减小趋势,其它月份增加或减小的趋势不显著;中部、西南部河流各月径流量增加或者减小的趋势不显著。汛期径流总量,北部和西北部河流有显著减小趋势,其它河流增加或减少的趋势不显著。

Distribution of Inner-annual Runoff in Main Rivers of Henan Province

Based on the monthly runoff series from the representative control stations of the four basins from 1950 to 2011, the concentration degree (Cd), concentration period (Cp), uneven coefficient (Cv) were used to study the distribution characteristics and law. And m-k test method was used to study the monthly runoff trend. The results show that from the south to north in Henan Province, there is a decrease trend of the monthly runoff concentration degree and heterogeneity, runoff focus has successive backwards, and there are two jump interval. Cd, Cv for the rivers of Yellow, Yiluohe and Weihe are in the low value interval, and Cd, Cv for the Huaihe River and its southern tributaries, the rivers of Hongruhe, Shayinghe and Tangbaihe are in the high value interval. After 1980, the runoff concentration is low, concentration period delay, uneven coefficient become small. In the northern and northwestern rivers, monthly runoff significantly decrease; the southern river runoff in April and May has a significant decrease trend, and increase or decrease trend is not significant in other months; and there is no significant runoff increase or decrease trend in the central, southwestern rivers. The total runoff in flood seasons in the north and northwest rivers have significant decrease trend, and there is no obvious increase or decrease trend in the other rivers.