调水调沙对黄河三角洲切变锋及冲淡水扩散的影响  

Characteristics of Shear Fronts and Dispersal of Diluted Water During the Water-Sediment Regulation Scheme in Yellow River Delta

作　　者：王柯萌 孙永福 宋玉鹏 徐丛亮 董立峰 WANG Ke-meng;SUN Yong-fu;SONG Yu-peng;XU Cong-liang;DONG Li-feng(First Institute of Oceanography,MNR,Qingdao 266061,China;Laboratory for Marine Geology and Environment,Pilot National Laboratory for Marine Science and Technology(Qingdao),Qingdao 266237,China;Institute of the Yellow River Estuary and Coast Science,Dongying 257000,China)

机构地区：[1]自然资源部第一海洋研究所,山东青岛266061 [2]青岛海洋科学与技术试点国家实验室海洋地质过程与环境功能实验室,山东青岛266237 [3]黄河河口海岸科学研究所,山东东营257000

出　　处：《海洋科学进展》2019年第4期551-564,共14页Advances in Marine Science

基　　金：国家重点研发计划——水合物形成与分解过程微观结构与宏观力学特性(2017YFC0307305);山东省自然科学基金项目——天然气水合物开采引起的地层沉降对海床稳定性的影响(ZR2017QD004);海洋公益性行业科研专项——近海海底地质灾害预测评价及防控关键技术研究(201005005);黄河口及邻近海域生态系统管理关键技术研究与应用(201105005)

摘　　要：基于Delft3D构建了包含利津以下河段的黄河口三维水动力数值模型,通过2011年调水调沙期间的大面站观测资料对模型进行了验证,结果表明模型可以很好地描述研究区的流场特征和盐度分布。通过3个工况,分析调水调沙对切变锋位置、强度、历时的影响,总结出地形成因和径流成因的两类切变锋。表层低盐中心位于入海口东北外海,与径流入海后形成的顺时针环流一致。底层淡水受地形成因切变锋面抑制,主要被限制在口门右侧的河口前缘,并沿岸线向ES—S扩散,形成底层低盐中心。高径流时表层冲淡水向北侧扩散更远且偏转半径更大;低径流时盐水楔位于河道内,外海盐度波动较弱。平流作用与水体净输移有关,提供了绝大部分的淡水通量;潮泵作用在近岸更为强烈,反映了口门两侧不同位置、层位截然相反的盐度-潮流相位关系。Based on Delft3 D, this study established a 3-D hydrodynamic numerical model for Yellow River delta and downstream river from Lijin. The model has been calibrated by field investigation data obtained during water-sediment regulation scheme in 2011, and it can be used to well reflect the hydrodynamic condition and salinity distribution in the study area. By analyzing three cases, this study indicated the influence of regulation scheme on the position, strength and duration of shear fronts caused by topography and runoff. Low-salt area, located at the northeast of inlet, was consistent with clockwise residual circulation in surface layer. Diluted water in bottom layer, limited by topography-induced shear front, dispersed to south and southeast along the coast in nearshore area, and formed a bottom low-salt area. On the contrary, diluted water could disperse to further north with a larger rotation radius as the result of increasingly discharge. Saline wedge was situated at river channel, and salinity changes in open sea were slight under low discharge. Advective flux, related to Eulerian residual transport velocity, made the greatest contribution of fresh water transport, while tidal pumping flux reflecting the phase lag between salinity and tidal current was noticeable only at the two sides of inlet.

关 键 词：黄河口 调水调沙 切变锋 冲淡水 数值模型 

分 类 号：P736[天文地球—海洋地质]