钱塘江河口尖山滩地短期演变及其影响因素  

Short-term Evolution of Jianshan Tidal Flat in Qiantang River Estuary and Its Influencing Factors

作　　者：朱沈鸣 李颖 陈刚[3] 潘冬子[3] ZHU Shen-ming;LI Ying;CHEN Gang;PAN Dong-zi(Qiantang River Basin Center of Zhejiang Province,Hangzhou 310020,China;School of Geomatics and Municipal Engineering,Zhejiang University of Water Resources and Electric Power,Hangzhou 310018,China;Zhejiang Institute of Hydraulics and Estuary,Hangzhou 310020,China)

机构地区：[1]浙江省钱塘江流域中心,浙江杭州310020 [2]浙江水利水电学院测绘与市政工程学院,浙江杭州310018 [3]浙江省水利河口研究院,浙江杭州310020

出　　处：《水电能源科学》2024年第6期73-77,共5页Water Resources and Power

基　　金：浙江省自然科学基金项目(LZJWY22E090006,LZJWZ22E090002);国家自然科学基金项目(42176214);浙江省水利河口研究院院长基金重点项目(ZIHE21Z001);浙江省水利科技计划重大项目(RA2210)。

摘　　要：滩槽冲淤演变是潮汐河口研究关注的重点问题之一。尖山河段位于钱塘江河口的过渡段,受径流和潮流共同作用,滩地冲淤变化幅度大、主槽摆动频繁。以往研究多局限于物理模型或数值模拟,缺乏与现场实测资料的对比分析。因此,以尖山滩地2020~2021年的实测地形数据为基础,结合近期水动力过程,分析滩面坡度、地形冲淤和典型断面高程的变化,并研究径潮动力对近期滩地演变的影响。结果表明,滩地呈现阶段性冲淤交替,汛前滩地成台阶状分布,横向存在多级陡坎;汛中近岸边滩大幅冲刷,离岸心滩略有淤积;汛后滩地普遍淤涨,近岸水流集中形成冲刷潮水沟。下泄径流和上溯潮流是尖山滩地演变的主要控制因素,径潮动力与滩地相互作用,形成“洪冲潮淤、大冲大淤”的形态格局。The evolution of flats and channels resulting from erosion and sedimentation is one of the key issues in the study of tidal estuaries.Jianshan Reach is located in the transition section of the Qiantang River estuary.Due to the combined effect of runoff and tidal current,the erosion and sedimentation of tidal flats vary greatly,and the main channel swings frequently.Previous studies were mostly limited to physical models or numerical simulations,lacking comparative analysis with on-site measured data.Based on the measured terrain data of Jianshan tidal flat from 2020 to 2021,combined with recent hydrodynamic processes,this paper analyzed the changes in flat slope,terrain erosion and sedimentation,and typical section elevation,and studied the impact of runoff and tidal dynamics on the recent evolution of the flat.The results show that the tidal flats exhibit periodic alternation of erosion and sedimentation,and are distributed in a stepped shape before the flood season,with multi-level steep ridges in the horizontal direction.During the flood season,there was significant erosion of the nearshore flats and slight sedimentation of the offshore channel bars.After the flood season,the floodplain generally silts up,and the nearshore water flow concentrates to form a scouring tidal channel.The main controlling factors for the evolution of the Jianshan tidal flat are the discharging runoff and upwelling tidal current.The interaction between the runoff and tidal dynamics and the tidal flat forms a morphological pattern of"flood erosion as well as tidal deposition,and large deposition after large erosion".

关 键 词：潮滩演变 钱塘江 潮汐 径流 强潮河口 

分 类 号：TV148[水利工程—水力学及河流动力学]