摘要
全球气候变化引起极端洪水频发和强度增大,增加流域洪水风险。甘河是嫩江尼尔基水库上游最大的支流,其洪水演变关乎下游尼尔基水库的防洪调度。本研究基于甘河1958~2018年的逐日气温、降水和径流等数据,利用块最大值模型和超阈值模型,在对洪水事件提取的基础上,分析了洪水事件发生次数、发生时间和洪峰流量的演变特征,并探究了洪水演变与降水、气温关系。结果表明:甘河流域洪水频发,61 a间共发生了124次洪水事件,且主要集中在5~10月。年最大洪峰流量总体呈增加趋势,增加速率为4.6 m^(3)/(s·a);年最大洪峰发生时间均有提前趋势,增加速率为0.37 d/a。洪水与气温相关性较弱,与降水密切相关,甘河流域易形成暴雨型洪水;洪峰发生前10 d的降水频率和强度与洪水的相关性最为密切,且年最大7日洪量和最大7日降水量变化趋势大致相当。研究成果可为甘河洪水风险管理和下游尼尔基水库的防洪调度与水安全保障提供参考。
The extreme floods caused by global climate change increase the flood risk in basins in a global scale.The Ganhe River is located in the upper reaches of Nenjiang River,and it is the largest tributary upstream of the Nierji Reservoir.The flood evolution pattern of Ganhe River is very important for the flood safety of the downstream Nierji Reservoir.The daily temperature,precipitation and runoff data of Ganhe River from 1958~2018 were collected and the flood events were extracted by the POT model and the BMM model.The evolution characteristics of flood event frequency,occurrence time and peak discharge were analyzed.The correlation between flood evolution and precipitation and temperature were determined.The results showed that the Ganhe River had experienced frequent flood events(124 times)that mainly concentrated in the wet season(May to October)for the past 61years.The annual maximum peak flow showed a significant increasing trend,with an increasing rate of 4.6 m^(3)/(s·a),and the annual maximum flood peak occurred earlier with an increasing rate of 0.37 d/a.Flood events were closely correlated with precipitation and were prone to the formation of flash floods.The precipitation frequency and intensity of 10d before the flood peaks were most closely correlated with floods,and the trends of annual maximum 7d flood volume and maximum 7d precipitation were roughly equivalent.The results can provide some supports for flood risk management in Ganhe River and flood control and water security of the downstream Nierji Reservoir.
作者
章清松
陈伟
吴燕锋
章光新
戴长雷
ZHANG Qingsong;CHEN Wei;WU Yanfeng;ZHANG Guangxin;DAI Changlei(School of Hydraulic and Electric Power,Heilongjiang University,Harbin 150080,China;Northeast Institute of Geography and Agroecology,Chinese Academy of Sciences,Changchun 130102,China;Songliao Water Conservancy Commission of Ministry of Water Resources,Changchun 130021,China)
出处
《人民长江》
北大核心
2023年第9期99-105,共7页
Yangtze River
基金
国家重点研发计划项目(2021YFC3200203)
国家自然科学基金项目(41877160,42101051)
中国博士后科学基金项目(2021M693155)。
