澜沧江流域径流演变规律研究

Rules of Runoff Variation in Lancang River Basin

摘要: 根据澜沧江小湾水库和糯扎渡水库1953~2014年的年均径流量资料，采用年内分配完全调节系数、年内集中度进行年内分配特征分析，运用累积距平法、Kendall非参数秩次相关检验法分析了澜沧江流域年均径流的趋势性变化；运用Mann-Kendall法进行了澜沧江流域年均径流的突变性分析；最后采用小波分析方法分析了年均径流的周期性变化，最终得出了澜沧江流域径流演变规律。结果表明：1) 澜沧江流域1953年~2014年小湾站和糯扎渡站的年均径流存在着较明显的丰枯季变化，年内分配不均匀程度多年来变化不大；2) 澜沧江流域多年来年均流量整体变化趋势不明显，局部存在着一些上升或下降的波动；3) 1981年为小湾站和糯扎渡站年均径流的可能突变开始点；4) 小湾站和糯扎渡站的年均径流主要存在19a显著变化周期。

Abstract: According to the annual average runoff data at Xiaowan and Nuozhadu stations in the Lancang River basin from 1953 to 2014, the characteristics of distribution were analyzed with the adjustable parameters and distribution concentrations, and the long-term trend of runoff was analyzed using accumulated variance analysis methods and the non-parametric Kendall test. Mann-Kendall test method was used to analyze mutation points of the runoff; and wavelet analysis method was used to identify cycle of runoff. Then rules of runoff variation in Lancang River basin can be analyzed. The results showed that 1) the runoff showed obvious seasonal change and the yearly uneven degree of runoff distribution from 1953 to 2014 in Lancang River basin changed little over years; 2) the overall trend of runoff at the two stations was not obvious, with an increasing or decreasing tendency during some years; 3) the runoff mutation point may be in the 1981; 4) 19-year variation cycle existed in Lancang River basin.