湛江港海域游泳动物群落结构及多样性分析

【目的】研究湛江港海域的游泳动物资源结构及多样性特征。【方法】根据2016—2017年湛江港海域4个季度的底拖网渔业资源调查数据,采用相对重要性指数(index of relative importance,IRI)、Margalef丰富度指数(D)、Shannon-Wiener多样性指数(H')、Pielou均匀度指数(J)和ABC曲线(abundance-biomass comparison curve)分析该海域游泳动物的种类组成、优势种和多样性水平等群落结构特征。【结果】该海域共发现游泳动物173种,隶属于16目68科116属;其中鱼类种类数最多(98种,占总种类数的56.7%),以底层鱼类和暖水性鱼类为主;其次是甲壳类(66种,占38.2%),头足类最少(9种,占5.2%)。4个季节的优势种累计有11种(鱼类6种、甲壳类5种),其中条纹叫姑鱼(Johnius fasciatus)是春、夏、秋3个季节的共同优势种。从时间维度上看,秋季的H'、D均为最高,而春季的J最高;从空间维度上看,湛江港口门处S6站位多样性水平相对较高。ABC曲线结果显示,湛江港海域游泳动物群落在冬季受干扰程度高于其它3个季节。【结论】湛江港海域游泳动物种类丰富,其中鱼类是主要的游泳动物类群。

Analysis of Nekton Community Structure and Diversity in Zhanjiang Harbour Waters

【Objective】To understand the key ecological processes in the coastal waters and their response to human activities.【Method】According to seasonal bottom trawl surveys were conducted from 2016 to 2017.The species composition,dominant species and diversity of nekton were analyzed by the indexes of relative importance(IRI),Margalef richness(D),Shannon-Wiener diversity(H'),Pielou evenness(J)and abundance-biomass comparison curve.【Result】A total 173 species were identified in the surveys.They consist of 16 orders,68 families and 116 genera.Among them,there were 98 fish species which account for 56.7%.They comprised mainly of demersal fish and warm-water fish.There were 66 species of crustacean,accounting for 38.2%and 9 species of Cephalopod accounting for 5.2%.The IRI results show that there were 11 dominant species,which including 6 species of fish,and 5 species of crustacean.Furthermore,Johnius fasciatus was the mutual dominant species in spring,summer and autumn.For temporal distribution,D and H'were the highest values in autumn,while J was the highest in spring.For spatial distribution,the diversity of station S6 is relatively higher,which is at the entrance of Zhanjiang Harbour.ABC curves show that the degree of disturbance for nekton communities is relatively higher in winter than the other three seasons.【Conclusion】The species of nekton in Zhanjiang Harbour waters were plentiful,and fish was the main group among them.