悖牛川径流年内分配变化规律研究

Change of Annual Runoff Distribution in Beiniuchuan River Basin

[目的]分析悖牛川径流年内分配变化特征,为流域水资源规划、管理和开发利用提供科学依据。[方法]根据悖牛川控制性水文站—新庙站1966—2010年实测月径流资料,分析年内分配不均匀系数、完全调节系数、集中度(期)等特性。并采用累积滤波器和Mann—Kendall秩相关法诊断各月径流量的变化趋势。[结果](1)总体上,悖牛川径流年内分配呈双峰型分布,其峰值分别出现在3和8月。径流年内分配很不均匀,8月份径流量达到最大值,占年径流量的37.63%;1月份降到最低值,仅占到年径流量的0.65%;(2)20世纪60—70年代的不均匀性和集中程度最大,80年代最小。最大径流出现在7月中下旬到8月上中旬,相对比较集中;(3)对于1966—2010年系列,各月径流量都处于显著减小的趋势。[结论]受气候和人类活动的影响,悖牛川月径流量年内分布不均且均呈现减少趋势。

[Objective]Distributional changes of annual runoff in Beiniuchuan River basin were studied to provide a scientific basis for water resource planning,management and exploitation.[Methods]Based on the observed monthly streamflow in Xinmiao station from 1966 to 2010,annual distributional unevenness and concentration degree were calculated.Then Mann—Kendall test and cumulative filter method were employed to detect the trend of intra-annual runoff.[Results]（1）Generally,seasonal runoff distribution was bimodal with two peak values in August and March.The annual runoff distribution was very uneven with its maximum in August,which accounted for 37.63%of annual runoff.The minimum runoff in January only accounted for 0.65% of it.（2）The unevenness and concentration degree of runoffs in 1960 sand 1970sreached the maximum,and they hit the lowest in 1980 s.The maximum runoff occurred in late July to mid-August,relatively concentrated.（3）Monthly runoff had an obvious declining trend from 1966 to 2010.[Conclusion]Resulted from climatic change and human activity,the annual runoff showed an uneven distribution and the monthly runoff had a declining trend.