拉尼娜事件前后北部湾鱼类群落结构变化研究  

Variation in fish community structure in Beibu Gulf before and after La Niña event

作　　者：李淼 许友伟[1,2] 孙铭帅[1] 范江涛[1] 李佳俊 张魁[1] 陈作志[1] LI Miao;XU Youwei;SUN Mingshuai;FAN Jiangtao;LI Jiajun;ZHANG Kui;CHEN Zuozhi(South China Sea Fisheries Research Institute,Chinese Academy of Fishery Sciences/Key Laboratory for Sustainable Utilization of Open-Sea Fishery,Ministry of Agriculture and Rural Affairs,Guangzhou 510300,China;College of Marine Sciences,Shanghai Ocean University,Shanghai 201306,China)

机构地区：[1]中国水产科学研究院南海水产研究所/农业农村部外海渔业可持续利用重点实验室,广东广州510300 [2]上海海洋大学海洋科学学院,上海201306

出　　处：《南方水产科学》2023年第2期1-11,共11页South China Fisheries Science

基　　金：国家重点研发计划项目(2018YFD0900906);广州市基础与应用基础研究项目(202201010639);中国水产科学研究院基本科研业务费专项资金(2020TD05)。

摘　　要：拉尼娜事件会影响鱼类的生活史和多样性,导致不同海域鱼类群落结构的演替。为掌握拉尼娜事件对北部湾鱼类群落结构的潜在影响,根据2006年7月和2008年7月北部湾海域底拖网渔业资源调查数据,分析拉尼娜事件发生前后鱼类群落结构的变化特征。结果表明,2006年夏季优势种为发光鲷(Acropoma japonicum)、竹荚鱼(Trachurus japonicus),2008年夏季优势种为竹荚鱼、蓝圆鲹(Decapterus maruadsi)、发光鲷,竹荚鱼和发光鲷为两航次共有优势种。多样性指数(H')与均匀度指数(E_(1)和E_(2))在年际间差异不显著,丰富度指数(D')差异显著。以发光鲷为代表的暖温性鱼类资源密度下降;以竹荚鱼、蓝圆鲹为代表的暖水性鱼类资源密度升高,并向北部湾沿岸方向移动,北部湾沿岸站点(C1—C22)的各指数在拉尼娜事件发生前后具有显著性差异(P<0.05)。聚类分析和非线性多维尺度排序结果表明,鱼类群落空间分布较为稳定,主要差异在海南岛西部沿岸。拉尼娜事件引起北部湾海域水温降低、初级生产力升高,导致竹䇲鱼、蓝圆鲹等小型中上层鱼类资源密度升高。在捕捞压力相对稳定的情况下,研究认为北部湾鱼类群落结构在拉尼娜事件前后存在显著的年际变化和物种更替现象。La Niña events will affect the life history and diversity of fish,leading to the succession of fish community structure in different sea areas.To understand the potential impact of La Niña events on the fish community structure in the Beibu Gulf,based on the bottom trawl survey data of fishery resources in July 2006 and July 2008,we analyzed the variation in the fish community structure in the Beibu Gulf before and after La Niña event.The results show that the dominant species were Acropoma japonicum and Trachurus japonicus in summer of 2006,and T.japonicus,Decapterus maruadsi and A.japonicum in summer of 2008.T.japonicus and A.japonicum were the common dominant species in the two years.The diversity index(H')and evenness index(E_(1) and E_(2))did not differ significantly between years,but the richness index(D')differed significantly.After the La Niña event,the density of warm-water fish resources,such as A.japonicum,decreased,while that of warm-water fish resources,such as T.japonicus and D.maruadsi,increased.Besides,T.japonicus and D.maruadsi moved towards the coast of the Beibu Gulf.The diversity index of the Beibu Gulf coastal sites(C1–C22)was significantly different before and after the La Niña event(P<0.05).The results of cluster analysis and non-metric multidimensional scale ranking show that the fish community spatial distribution was more stable,and the main difference was in the western coast of Hainan Island.The La Niña event resulted in a decrease in water temperature and an increase in primary productivity in the Beibu Gulf,causing an increase of the density in small pelagic fish stocks such as T.japonicus and D.maruadsi.In conclusion,when the fishing pressure is relatively stable,the significant variation in the fish community structure in the Beibu Gulf is closely related to the La Niña event.

关 键 词：拉尼娜事件 鱼类群落 生物多样性 优势种 北部湾 

分 类 号：S931.1[农业科学—渔业资源]