浙江省沿岸春秋季头足类群落结构变化分析

根据2014—2016年在春秋季(4月、5月、11月)浙江沿岸进行拖网调查,选取其中的头足类渔获,通过统计分析方法,分析了春秋季浙江沿岸在近年的种类组成和优势种,以及优势种的时空分布变化,并利用生态学方法对头足类群落结构变化进行了研究。结果显示,3年调查共鉴定头足类22种,隶属于3目7科10属,优势种主要为多钩钩腕乌贼、火枪乌贼、杜氏枪乌贼、剑尖枪乌贼、双喙耳乌贼、长蛸。浙江沿岸头足类群落分布呈现出时空差异,在春季(4—5月)北部站点以长蛸为主,其渔获率明显高于春季以剑尖枪乌贼为主的南部站点,秋季主要为多钩钩腕乌贼和火枪乌贼为主,2016年的渔获率明显低于前两年;聚类分析将不同年月和地区站点划分为两大群组,不同群落结构间存在显著差异,长蛸对群落区分度贡献最大,同时对群落空间结构起着决定性作用,而种群的洄游可能是影响浙江沿岸头足类群落结构季节性变化的主要因素。

Variation of community structure of Cephalopods in spring and autumn along the coast of Zhejiang Province

Coast of Zhejiang province is one of the important fishery production areas in China. As an important part of the marine ecosystem, cephalopods also play a very important role in the coastal fisheries of Zhejiang Province. Based on the trawl survey data in the coast of East China Sea during 2014-2016 in spring and autumn, all the cephalopods species were selected, we analyzed the species and dominant species composition using statistical methods, studied the spatial-temporal distribution of the dominant species, and also investigated the dynamic of community structure using the ecological methods. The results showed that a total of 22 species were captured and identified in the three-year survey, which belong to 3 orders, 7 families and 10 genus, dominant species were Abralia multihamata, Loliolus beka, Loligo duvauceli, Loligo edulis, Sepiola birostrata and Octopus minor. A spatial and temporal variation of cephalopod community were presented. Octopus minor dominated in the north station in spring, and its biomass density was higher than the south station, which dominated by Loligo edulis, Abralia multihamata and Loliolus beka were the dominant species in autumn, and the biomass density in 2016 is much less than the other two years before. Cluster analysis separated as two groups based on different years, months and stations, significant difference existed among community structures, Octopus minor made the largest contribution to the communities, and also made a decisive effect on the spatial community structure, individual migration may the main factor for the seasonal dynamic of community structures.