Dramatical hydro-sedimentary changes induced by bamboo fences over mangrove tidal flat of the largest delta in Beibu Gulf, southwestern China  

作　　者：Zuming Huang Zhijun Dai Riming Wang Xiaoyan Zhou Wenhong Pang Jiejun Luo Bingbin Feng Baoqing Hu 

机构地区：[1]Guangxi Key Laboratory of Marine Environmental Change and Disaster in Beibu Gulf,Qinzhou 535011,China [2]State Key Laboratory of Estuarine and Coastal Research,East China Normal University,Shanghai 200062,China [3]Key Laboratory of Coastal Science and Engineering/Qinzhou Key Laboratory for Eco-Restoration of Environment,Beibu Gulf University,Guangxi 535011,China [4]Key Laboratory of Environment Change and Resources Use in Beibu Gulf(Nanning Normal University),Ministry of Education,Nanning 530001,China

出　　处：《Acta Oceanologica Sinica》2023年第7期103-115,共13页海洋学报（英文版）

基　　金：The National Natural Science Key Foundation of China under contract No.41930537;the Key Research and Development Plan of Guangxi under contract No.AB21076016;the Marine Science Program for Guangxi First-Class Discipline,Beibu Gulf University;the China Postdoctoral Science Foundation under contract No.2022M721150.

摘　　要：Mangrove forest is one of the most important ecological and environmental resources by effectively promoting tidal flat deposition and preventing the coastal region from typhoon.However,there have been mass loss of mangrove forests due to anthropogenic activities.It is an urgent need to explore an effective way for mangrove restoration.Here,three rows of bamboo fences with hydro-sedimentary observation set over Aegiceras corniculatum mangrove tidal flat of the Nanliu Delta,the largest delta of Beibu Gulf,China,were conducted to analyze the hydro-sedimentary variations induced by bamboo fences.Results identified that the mean horizontal velocity Um per burst(20 min)decreased by as much as 71%and 40%in comparison with those without bamboo fences in March and November,respectively,when the tidal current entering the bamboo area during flood.The maximum of mean horizontal flow velocity Um-max at bamboo area was 50%–75%of that without bamboo fences during ebb tide.The suspended sediment concentration of bamboo area suggested a maximum reduction of 57%relative to bare flat during flood,and was 80%lower than bare flat at ebb peak.Moreover,the turbulent kinetic dissipationεat flood tide was significantly higher than that at ebb tide,while the bamboo fences greatly increased the turbulent kinetic dissipationεby 2 to 5 times relative to bare flat,resulting in an increase of the bed elevation by inhibiting the sediment incipient motion and intercepting suspended sediment.The siltation rate at the bamboo area was 140%and 29.3%higher than that at the bare flat and the region covered with A.corniculatum,respectively.These results highlight that bamboo fences can effectively attenuate tidal current and thus promote siltation over mangrove flat,which contribute great benefit to mangrove survival.

关 键 词：mangrove tidal flat bamboo fences hydro-sedimentary process bed siltation 

分 类 号：P736.21[天文地球—海洋地质]