枸杞岛海藻场两种大型海藻碎屑分解和沉降特征  

Decomposition and sedimentation of two species of macro algae detritus at the Gouqi Island seaweed beds

作　　者：夏艳芳 章守宇 王凯[1,2] 徐鹏 李娜[1,2] 李训猛 XIA Yanfang;ZHANG Shouyu;WANG Kai;XU Peng;LI Na;LI Xunmeng(School of Marine Ecology and Environment,Shanghai Ocean University,Shanghai 201306,China;Engineering Research Center of Marine Ranching,Shanghai Ocean University,Shanghai 201306,China)

机构地区：[1]上海海洋大学海洋生态与环境学院,上海201306 [2]上海海洋大学,海洋牧场工程技术研究中心,上海201306

出　　处：《水产学报》2023年第3期75-84,共10页Journal of Fisheries of China

基　　金：国家自然科学基金(41876191);现代农业产业技术体系专项(CARS-50);上海海洋大学科技发展专项(A2-2006-20-200207)。

摘　　要：岛礁水域海藻场是近岸海域典型的生态系统,大型海藻分解产生的碎屑是海藻场生态功能的重要基础。为探究大型海藻碎屑对海藻场生态功能潜在规模的贡献,本研究以枸杞岛海藻场孔石莼和舌状蜈蚣藻为对象,通过现场挂袋实验和室内静水沉降测试,分析了两种海藻碎屑的组分、粒径和沉降特征。结果显示,分解过程中舌状蜈蚣藻和孔石莼的碎屑密度均逐渐减小,且各自在不同分解时期无显著差异。舌状蜈蚣藻碎屑中有机C含量和有机N含量对密度变化影响不显著,孔石莼碎屑中有机C含量对密度没有显著影响,而有机N含量对密度有显著影响。孔石莼碎屑的δ^(13)C和δ^(15)N对其密度有显著影响,舌状蜈蚣藻碎屑的密度只受δ^(13)C影响。两种海藻碎屑的密度都受木质素含量的显著影响,受纤维素含量的影响不显著。粒径是两种海藻碎屑沉降速度的决定性要素之一,研究表明,舌状蜈蚣藻大型碎屑(粒径>0.830 mm)、中型碎屑(0.380~0.830 mm)和小型碎屑(0.180~0.380mm)的沉降速度分别为0.016~0.023、0.008~0.015和0.004~0.005 m/s,孔石莼碎屑相应的沉降速度分别为0.011~0.014、0.005~0.006和0~0.003 m/s。本研究为探寻大型海藻碎屑特征和海藻场的生态辐射范围提供了参考依据。The amount and species diversity of fish and other biological resources in island and reef waters are significantly higher than those in the surrounding waters,which is closely related to seaweed beds.As a typical offshore aquatic plant near islands and reefs,more than 90%of its energy enters the food chain in the form of detritus,providing an extremely important energy basis for the conservation and production of biological resources in island and reef waters.In order to explore the decomposition process of macroalgae,the composition and sedimentation characteristics of algal debris,and explore the contribution of macroalgae detritus to the potential scale of ecological functions of the seaweed beds,detritus of Ulva pertusa and Grateloupia livida from the seaweed beds of Gouqi Island was collected by on-site bag hanging and laboratory hydrostatic sedimentation process,and then analyzed in its composition,particle size and chemical characteristics.Results of the present study showed that the detritus density of U.pertusa and G.livida decreased gradually during the decomposition process,and there were no significant differences among different decomposition stages(P>0.05).The content of organic C and organic N in the detritus of G.livida had no significant effect on the change in density(P>0.05),while the content of organic C in the detritus of U.pertusa had no significant effect on its density(P>0.05),whereas the content of organic N had a significant effect on this index(P<0.05).U.pertusa fragmental δ^(13)C and δ^(15)N had a significant effect on its density(P<0.05),and the density of G.livida detritus was only affected by δ^(13)C(P<0.05).In the decomposition process,the lignin and cellulose contents of the fragments of the two seaweeds showed a downward trend,and the contents of the two components of the fragments of U.pertusa were higher than those of C.ligulate.The density of both algal detritus was significantly affected by lignin content(P<0.05),while the cellulose content had no significant effect on th

关 键 词：舌状蜈蚣藻 孔石莼 碎屑 沉降特征 粒径 密度 枸杞岛 

分 类 号：S932.7[农业科学—渔业资源]