根据2007年在北部湾进行的4季渔业资源底拖网调查资料,对该海域鱼类的种类组成、物种多样性和优势种的时空变化进行分析。本次调查共捕获鱼类323种,隶属于18目101科,以发光鲷(ACrOPOMA JAPOnICuM)、黄斑鲾(lEIOgnATHuS bInduS)、竹鱼(TrACHuruS JAPOnICuS)、二长棘鲷(PArArgyrOPS EdITA)和大头白姑鱼(ArgyrOSOMuS MACrOCEPHAluS)为主要优势种。分析结果表明,北部湾鱼类的优势种更替明显,总体趋势为k选择种类(以红笛鲷和黑印真鲨等为代表)被r选择种类(发光鲷、鲾科和天竺鱼科等为代表)所替代,即寿命长、个体大和营养级高的鱼类种类减少,寿命短、个体小和营养级较低的种类增多。鱼类的SHAnnOn-WIEnEr多样性指数(H’)以共同渔区北部海域最高(3.60),东北部海域次之(3.58),共同渔区南部海域最低(2.35),四季多样性指数为2.96~3.77,平均3.31。2007年多样性指数比1992-1993年低,但高于1998-1999年,表明近年来该海域捕捞压力有所减缓,使得渔业资源有一定的恢复。本研究旨在了解北部湾生物多样性和优势种的动态变化及演替状况,为该海域渔业资源的合理开发与可持续利用对策提供科学依据。Based on data collected by quarterly otter trawl surveys in the Beibu Gulf in 2007,the species composition,diversity and dominant species of fishes were analyzed.A total number of 323 fish species belonging to 101 families and 18 orders were collected.The dominant species were Acropoma japonicum,Leiognathus bindus,Trachurus japonicus,Parargyrops edita and Argyrosomus macrocephalus.Data analysis shows an apparent succession of the dominant species with an overall trend of the k-selection species (such as Lutjanus sanguineus and Carcharhinus menisorrah) being replaced by r-selection species (such as Acropoma japonicum,Leiognathus,and Apogonichthys).The abundances of long-lived,large-size,and high trophic level fishes decrease,while those of the short-lived,small-size,and low trophic level increase.The Shannon-Wiener diversity index (H') in the northern common fishing zone (3.60) was the highest,followed by that of the northeast Beibu Gulf (3.58),and the lowest (2.35) appeared in southern common fishing zone..The seasonal variation of the diversity index ranged from 2.96 to 3.77 with an average of 3.31.The diversity index was lower in 2007 than that in 1992-1993,but higher than that in 1998 1999.This indicates that fishing intensity has alleviated in the recent years and has resulted in recovery of the fishery resources.农业部近海渔业资源调查项目(070404);中央级公益性科研院所基本科研业务费专项资金(中国水产科学研究院南海水产研究所)项目(2007TS08;2009TS08;2010YD10);我国近海海洋综合调查与评价专项(908-01-ST09);广东省海洋渔业资源综合评价项目(GD908-02-05
