南海重要珊瑚礁过渡性水域软骨鱼类的组成与分布

2004年5—7月和2005年3—4月采用深水三重刺网在南海的羚羊礁、华光礁、银砾滩、东岛、滨湄滩、排洪滩、本固暗沙、比微暗沙、武勇暗沙、海鸠暗沙、双子群礁、中业群礁、鲎藤礁、美济礁、仁爱礁、仙宾礁、南方浅滩、棕滩、大渊滩、永署礁、南薰礁、牛轭礁、道明群礁等23座重要珊瑚礁过渡性水域进行了2个航次专业调查，其中有21座岛礁共渔获到7目15科33种408尾软骨鱼类，而美济礁和南方浅滩没有渔获到软骨鱼类。根据调查资料，通过物种各分类阶元的分布、优势度（IRI）和单位努力量渔获量等几个方面分析南海重要珊瑚礁过渡性水域软骨鱼类的组成与分布，旨在为南海珊瑚礁渔业资源的开发和管理提供科学依据。结果表明，西沙群岛的重量单位努力量渔获量范围为73～499kg／10^4m^2，其优势种类是迈氏条尾虹、灰六鳃鲨和黑梢真鲨；中沙群岛的重量单位努力量渔获量范围为114～245kg／10^4m^2，其优势种类是迈氏条尾虹、灰三齿鲨；南沙群岛除了美济礁和南方浅滩外其重量单位努力量渔获量范围为51～846kg／10^4m^2，其优势种类是黑梢真鲨、灰三齿鲨。

Composition and distribution of Cartilaginous fishes in the adjacent waters area of main Islands and reefs of South China Sea

From May to July 2004 and March to April 2005,two fishery resources survey cruises were carried out using trammel net in the adjacent waters area of 23 main Islands and reefs of South China Sea:Lingyang reef,Huaguang reef,Yinli bank,Dong island,Binmei bank,Paihong bank,Bengu shoal,Biwei shoal,Wuyong shoal,Haijiu shoal,Shuangzi reefs,Zhongye reefs,Houteng reef,Meiji reef,Renai reef,Xianbin reef,Nanfang bank,Zong bank,Dayuan bank,Yongshu reef,Nanxun reef,Niue reef and Daoming reefs.A total of 408 Cartilaginous fishes of 33 species from 7 orders and 15 families were caught in the adjacent waters area of 21 main Islands and reefs of South China Sea,except Meiji reef and Nanfang bank.Based on the data,this paper analyzed composition and distribution of Cartilaginous fishes in the adjacent waters area of main Islands and reefs of South China Sea using distribution of species diversity of fishes in systematic order, index of relative importance and catch per unit effort.It can be used as a reference for fishery resources exploitation and management of coral reefs of South China Sea.The results show that Taeniura meyeni,Hexanchus griseus and Carcharhinus limbatus were preponderant species,and CPUE ranged from 73 kg/10~4 m~2 to 499 kg/10~4 m~2 in the Xisha Islands;Taeniura meyeni and Triaenodon obesus were preponderant species,and CPUE ranged from 114 kg/10~4 m~2 to 245 kg/10~4 m~2 in the Zhongsha Islands;Carcharhinus limbatus and Triaenodon obesus were preponderant species,and CPUE ranged from 51 kg/10~4 m~2 to 846 kg/10~4 m~2 in the Nansha Islands except Meiji reef and Nanfang bank.