侵蚀浪条件下沉水植被对沙坝-潟湖海岸的冲淤影响研究  

Study of the erosion and deposition in a sandbar-lagoon system influenced by submerged vegetation under erosion wave conditions

作　　者：丛新 匡翠萍[1] 武云龙 夏子龙 CONG Xin;KUANG Cuiping;WU Yunlong;XIA Zilong(Tongji University,Shanghai 200092,China)

机构地区：[1]同济大学,上海200092

出　　处：《热带海洋学报》2022年第4期31-37,共7页Journal of Tropical Oceanography

基　　金：国家自然科学基金面上项目(41976159);国家重点研发计划项目(2019YFC1407900)。

摘　　要：全球海岸生态系统正遭受气候变化及人类活动带来的威胁,本文基于沙坝-潟湖系统海岸典型剖面形态,通过设计实施动床波浪水槽试验,定量研究了侵蚀浪条件下沉水植被对该系统海岸冲淤的影响。结果表明:沉水植被明显削弱了沙坝前坡波浪破碎区前缘的波高增大幅度,并使坝后波高衰减;植被作用使波浪反射和透射系数减小、耗散系数增大;侵蚀浪作用下,沙坝坝顶冲刷较明显,潟湖内呈淤积趋势,海岸前丘受波浪冲刷呈陡坎形态。植被影响下沙坝和前丘区域最大侵蚀厚度均减小;植被可减少沙坝净侵蚀量、潟湖内淤积量及离岸输沙量,对海岸前丘有较好的保护作用。Global coastal ecological system is being threatened by climate change and human activities.Based on a typical profile of sandbar-lagoon system and designed wave flume experiments with moving bed,we carried out a quantitative analysis on the effects of submerged vegetation on erosion and deposition under erosion wave conditions.The results show that the submerged vegetation obviously weakens the wave height that increaes in the margin of surf zone on the fore slope of sandbar,and wave attenuation occurs behind the sandbar.Wave reflection and transmission coefficients reduce and wave dissipation coefficient increases due to submerged vegetation.Under the action of erosion waves,the sandbar crest was eroded distinctly,the lagoon showed a deposition trend,and the coastal foredune was eroded in a scarp form.With the influence of vegetation,the maximum erosion thickness of sandbar and foredune zone decreases.In general,vegetation can reduce the net sandbar erosion,the deposition in the lagoon and the offshore sediment transport,which has a good protective effect on the coastal foredune.

关 键 词：侵蚀浪 沉水植被 沙坝-潟湖 冲淤 波浪衰减 

分 类 号：P737.13[天文地球—海洋地质]