澄碧河流域径流年内分配变化规律分析

基于澄碧河流域坝首和平塘水文站1963－2014年逐日实测径流资料，计算其径流年内分配的不均匀系数、完全调节系数和集中度等八个特征指标，分析了近52 a来该流域径流年内分配的均匀度，在此基础上，采用线性倾向估计、Mann-Kendall趋势检验法和R/S分析法研究了澄碧河流域径流年内分配特征指数的变化趋势。结果表明：近52 a来澄碧河流域径流年内分配不均匀性较强，变化幅度较大；径流年内分配的的洛伦兹不对称系数呈现增加趋势，其余特征指标均呈现减少趋势；年内集中期主要在7月，流域径流年内分布不均匀的主要原因是个别月份径流量较大；八个特征指数的Hurst值均大于0.5，故可预测澄碧河流域径流年内分配的特征指数序列呈现正持续性，与过去整体变化趋势保持一致；随着时间推移，澄碧河流域径流年内分配不均匀性越来越低，逐渐由不均匀向相对均匀转变。 Eight intraannual indexes of runoff,including non-uniform adjustment coefficient and concentration ratio,were calculated for Bashou and Pingtang stations during 1963-2014 in the Chengbi River Basin.,The trend of annual runoff was detected with linear regression,Mann-Kendall trend test and R/S analysis.The results show that the intraannual runoff distribution is highly uneven in the past 52 years and varies with time in the Chengbi River Basin.The inhomogeneity of runoff distribution is increasing,and all other indices decrease.The concentration period is mainly in July,and Lorenz asymmetry coefficient shows that the main cause of uneven annual runoff distribution is the months with larger runoff.The Hurst values of eight indices are all greater than 0.5,which can be used to predict the annual distribution of runoff in the Chengbi River Basin.A positive continuity is consistent with the overall trend of the past.The intraannual distribution of runoff became lower and lower as time goes,which gradually transform from non-uniformity to homogeneity processes in the Chengbi River Basin. 国家自然科学基金（51569003；51609041）；广西自然科学基金（2017GXNSFAA198361）