1950—2016年赣江径流量变化特征及其影响因素分析

Analysis on annual runoff variation characteristics of Ganjiang River and its influence factors from 1950-2016

为了阐明赣江径流近50多年的变化特征及影响因素,以赣江外洲水文站1950-2016年水文资料为基础,利用距平累积法分析赣江径流年际变化特征,结合Mann-Kendall检验法和滑动T检验法对赣江径流特征进行突变性检验,采用Morlet小波分析法对径流序列进行周期性分析,并对导致赣江径流序列产生这种特征及其变化趋势的原因进行了讨论。结果表明:(1)赣江10a径流量呈现增加趋势,10a径流量最小值发生在20世纪60年代,最大值发生在2010-2016年;(2)1962-1963年和2010-2011年的赣江径流累积距平和年均径流量均呈现显著下降状态,且前者的变化特征比后者更加显著;(3)Mann-Kendall检验结果和滑动T检验结果均表明赣江年均径流在1991年前后存在着明显的突变性特征;(4)17a、6a和3a这3个周期的波动控制着赣江外洲水文站在1950-2016年这整个时间域内的变化特征;(5)赣江径流受气候变化和人类活动共同作用,气候变化主要影响径流长期变化趋势,径流变化的突发点与人类活动关系更大。研究结果可为鄱阳湖流域赣江水资源科学、合理的规划及利用提供一定的参考依据。

In order to clarify the annual runoff variation characteristics of Ganjiang River and its influence factors over the past 50 years,a mutation test on the runoff characteristics of Ganjiang River is made through combining the method of Mann-Kendall test with the method of Moving t-test by means of analyzing the annual runoff variation characteristics of Ganjiang River on the basis of the hydrological data from 1950 to 2016 obtained from Waizhou Hydrological Station of Ganjiang River,and then the periodic feature of the runoff series is analyzed with the method of Morlet wavelet analysis,while the causations of the characteristics of the runoff series of Ganjiang River and the variation trends are discussed herein as well.The results show that(1)the mean 10a runoff of Ganjiang River exhibits an increasing trend with the maximum value in 2010-2016 and the minimum value in 1960s;(2)both of the cumulative departure and the mean annual runoff are significantly declined during 1962-1963 and 2010-2011,and the characteristics of the former is more significant than that of the latter;(3)the results from both Mann-Kendall test and Moving t-test show that obvious mutation characteristics before and after 1991 are there for the annual runoff of Ganjiang River;(4)the variation characteristics of the mean annual runoff at Waizhou hydrological station of Ganjiang River within the whole time domain from 1950 to 2016 are controlled by the three periodic fluctuations of 17-years,6-years and 3-years;(5)the runoff of Ganjiang River is under the impacts of both the climate change and the human activities;for which the climate change mainly impacts the long-term changing trend,while the mutation point of the runoff variation is more related to the human activities.This study result can provide a certain referential basis for the scientific and reasonable planning and utilization of the water resources of Ganjiang River within Poyang Lake Basin.