鄱阳湖流域年际径流及丰枯变化分析

Variation Characteristics of Annual Average Runoff and Evolution Law of High and Low in Poyang Lake Basin

基于鄱阳湖流域1956-2012年6个水文站的逐日流量资料,利用变差系数、年际极值比、Kendall秩次相关检验、距平百分率、Markov过程多种分析方法,分析了鄱阳湖流域的径流年际及丰枯变化规律。结果表明,鄱阳湖流域的流量年际变化相对稳定,年径流量呈不显著的增加趋势;出现连枯水年的概率高于连丰水年概率;在丰枯转移的Markov过程中,平水年的自转移概率最大,重现期最短;丰水年与枯水年互转的概率最大,且出现枯水和偏枯水的概率大于出现丰水和偏丰水的概率;无论年径流处于何种初始状态,其向平水年转移的概率最大。

Based on the daily flow data of six stations in Poyang lake basin from 1956 to 2012, the coefficient of variation, inter-annual extremum ratio, the methods of Kendall trend test, anomaly percentage, the basic theory of Markov process are adapted to study the variation characteristics of annual average runoff and the evolution law of high and low in Poyang lake basin. The results shows that the inter-annual variability of Poyang lake basin is relatively stable, and the increasing trend of annual runoff is not significant; the occurrence probability of low year is higher than high year; in the Markov transfer process of high and low year, self-transition probability of the average year is the largest and return period is the shortest; while the maximum probability of transform occurs in high and low years, and the probability of low year or partial low year is greater than that of high year or partial high year; no matter how the initial state of annual runoff is, it prefers to transfer the state of average water.