帆张网渔获物组成及其多样性分析

根据2007年12月～2008年6月在东海北部和黄海南部海域调查所获取的资料,分析了帆张网作业渔获物组成及其多样性特征。结果显示,调查采获的鱼类41种,甲壳类22种,头足类3种。其中主要渔获物由小黄鱼（Pseudosciaena polyactis）、带鱼（Trichiurus haumela）、细条天竺鱼（Apogon lineatus）、太平洋褶柔鱼（Todarodes pacificus）、长枪乌贼（Loligo bleekeri）和细点圆趾蟹（Ovalipes punctatus）等10个种类组成,其质量占总样品质量的79.86%。对小黄鱼和带鱼进行体长和体质量组成分析得出,其幼鱼比例分别为97.20%和61.00%。物种种类丰度和多样性指数值显示,鱼类1月较高,而4、5和6月相对较低;甲壳类在5月较高,而4月相对较低。现行的帆张网渔获物中幼鱼比例较高,对经济幼鱼资源的损害较严重。

Analysis of composition and diversity of catches by stow net

According to the survey data obtained in northern East China Sea and southern Yellow Sea from Dec.2007 to Jun.2008,we studied the composition and diversity of catches by stow net.The results show that there are 41 kinds of fish,22 crustaceans and 3 cephalopods.The catches are mainly composed of 10 species such as Pseudosciaena polyactis,Trichiurus haumela,Apogon lineatus,Todarodes pacificus,Loligo bleekeri and Ovalipes punctatus.Their weight occupies 79.86% of the total catches.After analyzing the composition of length and weight of small yellow croaker and hairtail juveniles,we find they occupy 97.20% and 61.00% of the catches,respectively.The species abundance and diversity index indicate that the value of fish is rather high in January while relatively low in April,May and June.Crustaceans have higher value in May and lower one in April.Juveniles occupy a relatively high proportion of the catches by stow net,which damages the commercial larval resource rather seriously.