基于SRI的浑河流域水文干旱特征分析

Analysis on Drought Characteristics in the Hunhe River Basin Based on SRI

以浑河流域为研究对象,以标准化径流指数(SRI)为工具,选择流域内3个代表性水文站1975—2014年的逐月径流量为实验数据,计算不同时间尺度的SRI,采用游程理论和Mann-Kendall趋势性检验法,分析了流域水文干旱时空演变特征。研究表明:自1975年以来浑河流域干旱化呈减弱趋势,旱涝过程具有较好的周期性,平均每14~16年经历一次旱涝过程;流域的干旱在时间上呈现季节特征,春、夏、冬季干旱化趋势减弱,秋季呈现不显著的干旱化趋势,降水对流域水文干旱趋势和季节差异具有较大影响;流域发生干旱的频次由大到小依次为中游、下游、上游区域,上、中游以轻旱和中旱为主,下游较上、中游更可能发生重旱和特旱。

Based on the monthly runoff data of 3 typical hydrological stations in the Hunhe River Basin from 1975 to 2014,this paper calculates the standardized runoff index(SRI)at different time scales,and analyzes the spatial-temporal characteristics of hydrological drought by the Mann-Kendall test and the run-time theory.The results show that:since 1975,the aridification of the Hunhe River Basin has presented a weakening trend,and the drought and flood process has showed a good periodicity,with an average of one drought and flood process every 14~16 years.In terms of time,the drought in the basin presented seasonal characteristics,with a weakening trend of aridification in spring,summer and winter,and an insignificant trend of aridification in autumn.Precipitation had a greater impact on the hydrological drought trend and seasonal differences in the basin.The frequency of drought in the basin ranged from large to small in the middle,lower and upper reaches.The upper and middle reaches were dominated by light and medium droughts,while the lower reaches were more likely to suffer severe and extreme droughts than the upper and middle reaches.