基于Copula函数的大通站水沙特征分析  

Analysis of runoff and sediment characteristics of Datong Station based on Copula function

作　　者：黄宇明 缴健[1] 窦希萍[1] 郭海军 丁磊[1] HUANG Yuming;JIAO Jian;DOU Xiping;GUO Haijun;DING Lei(Key Laboratory of Port,Waterway and Sedimention Engineering of MOT,Nanjing Hydraulic Research Institute,Nanjing 210029,China;State Key Laboratory of Water Resources and Hydropower Engineering Science,Wuhan University,Wuhan 430072,China)

机构地区：[1]南京水利科学研究院港口航道泥沙工程交通行业重点实验室,江苏南京210029 [2]武汉大学水资源与水电工程科学国家重点实验室,湖北武汉430072

出　　处：《水利水运工程学报》2022年第4期37-45,共9页Hydro-Science and Engineering

基　　金：国家自然科学基金资助项目(51979172);水利部三峡后续工作项目(12630200100020J001)。

摘　　要：长江口受人类活动影响较为强烈,其水沙序列一致性遭到破坏。以大通站1965—2019年逐月径流量和来沙量资料为基础,采用滑动窗口算法结合Copula理论的方法,研究长江口来水来沙变化特征及丰枯一致性问题,并分析水沙联合分布模型边缘函数选取不确定性问题。结果表明:(1)受人类活动的影响,大通站水沙组合在1965—2019年间均呈减少趋势,并且在1979和2000年发生突变,水沙序列1965—1979年和1980—2000年阶段最优函数模型均为Clayton模型,2001—2019年则为Frank模型;(2)大通水文站3个阶段水沙序列同步频率分别是84.52%、84.40%和83.20%,远大于丰枯异步频率,揭示了长江上游来水来沙条件具有较强的一致性;(3)PE3-PE3边缘分布组合的95%置信区间小于PE3-GPD组合,说明采用PE3-PE3组合可以减少函数选取的不确定性。通过探讨大通站来水来沙联合变化特征,可为长江口水域水资源管理、河道整治等工作提供参考。The Yangtze River estuary has been strongly influenced by human activities,and the consistency of its runoff-sediment sequence has been damaged.Based on the monthly runoff and sediment data from 1965 to 2019 at Datong Station,a sliding window algorithm based on Copula is applied to investigate the variation characteristics of runoff and sediment in the Yangtze estuary and the consistency of its abundance-depletion,and the uncertainty of the marginal distribution selection for the joint runoff-sediment distribution model is also analyzed.The results show that:(1)The runoff-sediment combination at Datong Station shows a decreasing trend from 1965 to 2019 due to human activities,and changes abruptly in 1979 and 2000.The optimal function models for the runoff-sediment series in 1965—1979 and 1980—2000 are Clayton,while 2001—2019 is best modeled by Frank;(2)the synchronous frequencies of the runoff-sediment series in the three periods are 84.52%,84.40%and 83.20%respectively,which are much greater than the asynchronous frequencies of abundance-depletion,revealing the strong consistency of the incoming runoff-sediment in the upper reaches of the Yangtze River;(3)the 95%confidence interval of the PE3-PE3 marginal distribution combination is smaller than that of the PE3-GPD combination,indicating that the PE3-PE3 combination would reduce the uncertainty of function selection.By exploring the joint variation characteristics of incoming runoff and sediment at Datong station,this study provides a reference for water resources management and river regulation in the Yangtze estuary.

关 键 词：长江口 大通站 滑动Copula函数 水沙组合 联合分布 不确定性分析 

分 类 号：P333[天文地球—水文科学]