论文部分内容阅读
为了掌握荆江三口入洞庭湖径流泥沙演变规律,运用Mann-Kendall非参数检验法、小波分析以及均值差异t检验法等方法,对荆江三口(松滋口、太平口和藕池口)入洞庭湖1951—2011年年径流量和年输沙量进行了分析,在总结三口水沙过程演变规律的基础上,探讨了荆江三口入洞庭湖径流泥沙变化规律及其影响因素。结果表明:①荆江三口径流量发生显著变化集中在1960年代和1970年代,而输沙量突变点发生在1950年代,此后三口水沙演变始终表现出显著的递减趋势;②太平口和藕池口的径流量和输沙量演变周期保持一致,均为31 a的周期变化,松滋口和宜昌站的径流量和输沙量分别具有相同的周期性,分别为16 a和33 a的周期变化;③人为因素只是加速荆江三口分流分沙衰减趋势,但并不是致使其水沙演变发生突变的原因。
In order to grasp the evolution of runoff and sediment in Dongting Lake from three reservoirs in Jingjiang River, using the methods of Mann-Kendall nonparametric test, wavelet analysis and mean difference t-test, The annual runoff and annual sediment transport volume from 1951 to 2011 were analyzed. Based on the summary of the evolution of the three water and sediment processes, the variation of runoff and sediment flow into the three Dongjing Lake into the Jingjiang River and its influencing factors were discussed. The results show that: (1) Significant changes of runoff in Jingjiang River three occurred in the 1960s and 1970s, while the abrupt change of sediment discharge occurred in the 1950s, and the water and sediment evolution of the three had a decreasing trend all the time; (2) The runoff of sediment and runoff are the same, which are all 31-year cycle variation. The runoff and sediment transport of Songzikou and Yichang stations have the same periodicity, which are respectively 16 and 33 a cycles. ③ Human factors only accelerate the decay trend of diversion and sediment in the three ports of Jingjiang River, but it is not the reason that causes the sudden change of water and sediment.