摘要
2018年至2021年黄河河口春季生态调水与2次罕见大洪水,导致时段内入海水沙过程和水沙通量发生变化。为了解滨海地貌变化特征,根据海域实测地形资料,结合同期利津水文站来水来沙数据,分析了河口滨海区2、5和10 m等深线变化及冲淤演变,比较了现河口各汊三角洲前缘发育情况。结果表明:2018年至2021年河口年均入海水沙分别为362亿m^(3)和2.81亿t,是2002年至2017年入海水沙均值的2倍;4 a间入海泥沙共11.67亿t(包括尾闾河道冲刷0.42亿t),其中有8.58亿t(6.13亿m^(3))落淤在现行河口滨海区;洪峰呈漫流入海,入海汊口稳定性变差,加速河口出汊摆动演变,口门前方形成长轴平行岸线、短轴垂直岸线的椭圆形连续狭长淤积带,三角洲前缘得到充分发育;大洪水期间,河口在东北向自然出汊,东汊和东北汊成为入海主汊。
The ecological water regulation in spring and the occurrence of two rare floods in the area of the Yellow River Estuary from 2018 to 2021 led to the changes in water and sediment flux and process.In order to know the changes in geomorphological characteristics in the coastal area of the estuary,the changes of 2 m,5 m and 10 m isobaths,the evolution of erosion and deposition,as well as the development of delta fronts of each branch of the current estuary are analyzed and compared,according to the measured bathymetric data and combined with the water and sediment data of Lijin Hydrological Station in the same period.The results show that the average annual amount of water and sediment delivered into the sea from 2018 to 2021 is 36.2 billion m3 and 281 million tons respectively,being twice of that from 2002 to 2017.In the 4-year period a total of sediment delivered into the sea is 1,167 billion tons(including 42 million tons from the tail river channel erosion),of which approximately 858 million tons(about 613 million m3)of the sediment are deposited in the coastal area of the current estuary.At the flood time the flood peak flows into the sea in the form of diffuse flow and the stability of the tributary mouths is weakened.As a result,the branching and oscillating evolution of the estuary is accelerated and an elliptical,continuous and narrow silting zone with its horizontal axis parallel to the shoreline and its short axis vertical to the shoreline is formed in front of the tributary mouths.The delta fronts are fully developed due to the sufficient water and sediment supply.During great flood,the estuary can naturally branch in the northeast and the east branch and the northeast branch become the main branches into the sea.
作者
吴文娟
范勇勇
WU Wenjuan;FAN Yongyong(Institution of the Yellow River Estuary and Coast Science,Dongying 257091,China)
出处
《海岸工程》
2023年第1期52-60,共9页
Coastal Engineering
基金
国家自然科学基金项目(U2243208)
国家自然科学基金委员会与山东省人民政府联合资助项目(U1706214)。
关键词
水沙情势
大洪水
滨海冲淤
黄河口
water and sediment regime
great flood
erosion and accretion
Yellow River Estuary
