淤泥质潮间带植被-光滩沉积物稳定性研究——以长江口崇明东滩为例  

Study on sediment stability between vegetation and bare flats in a muddy intertidal flat:A case study for Chongming Dongtan in the Yangtze River Estuary

作　　者：张莹鑫 张文祥[1] 史本伟[1,2] 汪亚平 ZHANG Yingxin;ZHANG Wenxiang;SHI Benwei;WANG Yaping(State Key Laboratory of Estuarine and Coastal Research,East China Normal University,Shanghai 200241,China;Key Laboratory of Coastal Science and Integrated Management,First Institute of Oceanography,Ministry of Natural Resources,Qingdao,Shandong 266061,China)

机构地区：[1]华东师范大学河口海岸学国家重点实验室,上海200241 [2]自然资源部第一海洋研究所自然资源部海岸带科学与综合管理重点实验室,山东青岛266061

出　　处：《华东师范大学学报（自然科学版）》2022年第6期169-177,共9页Journal of East China Normal University(Natural Science)

基　　金：国家自然科学基金(42076170,U2240220);自然资源部海岸带科学与综合管理重点实验室开放基金(2021COSIMZ001);上海市教育委员会科研创新计划项目(2019-01-07-00-05-E00027)。

摘　　要：以典型淤泥质潮间带—长江口崇明东滩为例,通过现场采样和室内实验,对盐沼植被-光滩中沉积物的稳定性进行对比分析.结果表明:(1)在光滩区域,随着黏土含量的增加,沉积物稳定性增强.(2)受植被根系“加筋”作用,盐沼植被带沉积物稳定性明显高于光滩.(3)同一类型植被带的沉积物稳定性由地下生物量决定,地下生物量越高,沉积物越稳定;不同类型植被带的沉积物稳定性由植被根系特征决定,与具有较细根系的海三棱镳草相比,较粗根系的互花米草植被带内沉积物稳定性差.本研究结果不仅丰富了潮间带沉积物稳定性研究理论,而且还可为绿色海堤建设、海岸绿色防护措施制定提供科学依据.With the present global warming scenario,the erosion of intertidal flats in estuarine zones often occurs due to rising sea levels and an increase in human activities.Intertidal flats have an important ecological function and economic value,including for carbon sequestration,preventing flooding,water purification,attenuating waves,and tourism development.Hence,it is of great theoretical and practical significance to study the stability of the wetland ecosystem for intertidal flats.Previous studies mainly focused on the stability of intertidal bare flats,while the stability of salt marsh ecosystems has attracted relatively less attention.The mechanisms of their respective influencing factors are,as of yet,poorly understood.In this study,we took a typical muddy intertidal zone of Chongming Dongtan in the Yangtze River Estuary as an example and made a comparative analysis on sediment stability for both the salt marsh zone and the adjacent bare flat using in-situ sampling and laboratory tests.The results indicate that:(1)Sediment stability improves with an increase of clay content in the bare flat.(2)Sediment stability in the salt marsh zone is significantly higher than that in the adjacent bare flat because of the“reinforcing”effect of the root system.(3)Underground biomass determines sediment stability for the same type of vegetation.The sediment becomes more stable with an increase of the underground biomass in vegetation.The sediment stability of different vegetation is determined by characteristics of the vegetation root system.The sediment stability of Spartina alterniflora vegetation zone with coarser roots was worse than that of Scirpus mariqueter with finer roots.Our results not only advance theoretical research on sediment stability in intertidal flats,but also provide scientific guidance for the construction of Green Sea Defence and other coastal green protection measures.

关 键 词：沉积物稳定性 临界剪切应力 淤泥质潮间带 盐沼植被 沉积物粒度 

分 类 号：P737.121[天文地球—海洋地质]