摘要
洪水遭遇是指干支流或区域内多源洪水在短时间内叠加的水文现象。基于1953—2020年逐日观测水文数据,构建长江-鄱阳湖-五河系统的Copula洪水遭遇模型,并结合MIKE 21水动力模型,分析不同历时洪水过程的遭遇概率及其对湖区水位的影响。结果表明:鄱阳湖东部饶河与长江干流的洪水遭遇概率最高,洪水遭遇概率呈“北高南低、东高西低”的空间格局;100 a一遇的1、15和30 d最大洪水过程遭遇概率分别为0.026×10^(-3)、0.265×10^(-3)和0.746×10^(-3);赣江与长江干流同时发生洪水时,湖区水位上升最显著,92.86%的区域水位增幅超0.1 m;三峡水库汛期蓄水显著降低了洪水遭遇风险,使不同历时(1、15和30 d)100 a一遇洪水的遭遇概率分别下降了57.14%、89.10%和84.41%。
Flood encounter is a hydrological phenomenon where floods from multiple sources coincide within a short timeframe.Based on daily hydrological observation data from 1953 to 2020,this study constructed a Copula-based flood encounter model for the Yangtze River-Poyang Lake-Five Tributaries system.Combined with the MIKE 21 hydrodynamic model,We analyzed the encounter probabilities of flood process with different durations(1-day,15-day,30-day maximum floods)and their impacts on lake water levels.The results show that the encounter probability exhibited a spatial distribution pattern of“high in the north and east,but low in the south and west”,peaking with that of the Raohe and the mainstream of Yangtze River.The 100-year flood encounter probabilities for durations of 1,15,and 30 days were 0.026×10^(-3),0.265×10^(-3),and 0.746×10^(-3),respectively.The simultaneous occurrence of floods in the Ganjiang and the Yangtze mainstream caused the most significant water level rise in the lake area,with 92.86%of the region experiencing an increase exceeding 0.1 m.It is evident that the Three Gorges Reservoir flood-season storage significantly reduced the risk of flood encounter.Specifically,the encounter probabilities of 100-year floods for durations of 1,15,and 30 days decreased by 57.14%,89.10%and 84.41%,respectively.
作者
孙童
李相虎
黄幸
宋雅妮
徐力刚
SUN Tong;LI Xianghu;HUANG Xing;SONG Yani;XU Ligang(State key Laboratory of Lake and Watershed Science for Water Security,Nanjing Institute of Geography and Limnology,Chinese Academy of Sciences,Nanjing 211135,China;University of Chinese Academy of Sciences,Beijing 100049,China;Poyang Lake Wetland Observation and Research Station,Naning Institute of Geography and Limnology,Chinese Academy of Sciences,Jiujiang 332899,China)
出处
《水资源与水工程学报》
北大核心
2025年第6期19-26,34,共9页
Journal of Water Resources and Water Engineering
基金
国家重点研发计划项目(2022YFC3204102)
赣鄱俊才支持计划项目(20232BCJ22011)
江西省科技计划项目(20252ABF010001、20244BCF61001)
九江市科技计划项目(2025_000773)
国家自然科学基金项目(42171037)。
