马鞍列岛及其东部海域鱼类群落格局与环境因子之间的关系

Fish community structure and its relationship with environmental factors in the Ma’an Archipelago and its eastern waters

为探究岛礁海域渔业资源群落格局,于2016年8月、12月及2017年2月和5月对马鞍列岛及其东部海域进行了渔业资源季度调查。利用聚类分析、非度量多维标度(nMDS)和生物环境相关分析(BIOENV)等方法,对该海域的鱼类群落组成、时空动态及其与环境因子的相关性进行了研究。共采集鱼类96种,隶属于12目47科77属,其中鲈形目占比最大,其生物量和丰度占比均超过50%。龙头鱼为全年优势种,春季优势种包括刺鲳、黑鳃梅童鱼和宽体舌鳎;夏季优势种为小黄鱼、带鱼和六丝矛尾虾虎鱼;秋季和冬季优势种相同,为棘头梅童鱼和凤鲚。聚类分析和nMDS结果显示,马鞍列岛及其东部海域鱼类群落可分为站位组I(岛礁周围站点为主)、站位组II(邻近岛礁站点为主)和站位组III(远离岛礁站点为主)。除春季站位组I与站位组III、站位组II与站位组III外,鱼类群落种类组成在各季节不同站位组之间皆存在显著差异。BIOENV分析显示,在底层水温、底层盐度和水深3个因素中,底层水温对鱼类群落影响最大。

To study the fish community structure in islands area,a fishery-independent survey was conducted in August and December of 2016,February and May of 2017.The cluster analysis,nonmetric multidimensional scaling(nMDS)and biological environment correlation analysis(BIOENV)were used to study the composition of fish community in our study area.A total of 96 species were collected,which belonged to 77 genera,47 families and 12 orders.The Perciformes has maximum ratio,which accounted for more than 50%of their biomass and abundance.Harpadon nehereus was the dominant species throughout the year.In addition,the dominant species in spring were Psenopsis anomala,Collichthys niveatus,and Cynoglossus robustus;the dominant species in summer were Larimichthys polyactis,Trichiurus lepturus,and Chaeturichthys hexanema;the dominant species in autumn and winter were Collichthys lucidus and Coilia mystus.The fish community in the Ma’an Archipelago and its eastern waters can be divided into group I(the sites sorrounding island and reef),group II(the sites adjacent to reef),and group III(the sites far off island and reef).There were significant differences in species composition between groups,and seasons(R=0.651~0.977),except the spring group I and group III,group II and group III.BIOENV analysis showed that the bottom water temperature had the most significant impact on the fish community compared to bottom salinity and water depth.