南沙群岛渚碧礁鱼类分类多样性研究

根据1999-2018年南沙群岛渚碧礁礁栖鱼类流刺网和手钓调查资料,分析了渚碧礁礁栖鱼类物种组成及分类多样性,计算了其平均分类差异指数(Δ^+)及分类差异变异指数(Λ^+)。结果显示,渚碧礁礁区共记录礁栖鱼类11目43科93属152种,其中鲈形目鱼类占绝对优势(76%);渚碧礁鱼类的Δ^+为58.75,Λ^+为102.60。与国内外其他生态系统鱼类群落组成的对比发现,渚碧礁鱼类的Δ^+高于赵述岛、米尔恩湾和圣何塞岛,低于东海陆架、南沙群岛西南陆架、北部湾和大亚湾,而Λ^+则均低于其他群岛。研究表明渚碧礁鱼类群落物种间的亲缘关系比东海陆架、南沙群岛西南陆架、北部湾和大亚湾更为接近,但比赵述岛、米尔恩湾和圣何塞岛远。物种多样性较高而分类多样性较低是渚碧礁礁栖鱼类多样性分布格局的主要特征。但该礁易受到人类活动的干扰,应及时给予保护。

Study on taxonomic diversity of fish in Zhubi Reef of Nansha Islands

According to the survey data of gill net and hand fishing in Zhubi Reef of Nansha Islands in 1999-2018,we analyzed Zhubi Reef fish species composition and the classification of diversity,calculated the average classification difference index(Δ^+)and classification difference variation index(Λ^+).Altogether 152 species of reef fish belonging to 11 Orders,43 Families and 93 Genera had been found.Among them,Perciformes fish accounted for an absolute advantage(76%).TheΔ^+andΛ^+of Zhubi Reef fish were58.75 and 102.60,respectively.Compared with the composition of fish communities in different ecosystems at home and abroad,theΔ^+of the fish in Zhubi Reef was higher than those in Zhaoshu Island,Milne Bay and San Jose Island,but lower than those in the East China Sea Shelf,the South China Shelf of Nansha Islands,Beibu Gulf and Daya Bay.TheΛ^+of the fish in Zhubi Reef was lower than those in the other islands.It is indicated that the genetic relationship among the species in Zhuubi Reef fish community is closer than those in the East China Sea Shelf,the southwest shelf of Nansha Islands,Beibu Gulf and Daya Bay,but farther than those in Zhaoshu Island,Milne Bay and San Jose Island.The fish diversity of Zhubi Reef is characterized by higher species diversity but lower taxonomic diversity.However,the reef is vulnerable to human activities and should be protected in a timely manner.