南沙群岛渚碧礁大型底栖动物群落特征

Macrobenthic community characters of Zhubi Reef,Nansha Islands,South China Sea

利用2002年5月12日至5月21日在南沙群岛渚碧礁用轻潜水(SCUBA)方法于该礁盘不同位置设立的4个定量取样站采集的调查资料,采用IRI指数、ABC曲线方法和大型多元统计分析软件PRIMER对渚碧礁大型底栖动物进行等级聚类分析(CLUSTER)和非度量MDS标序,研究群落结构格局以及用Shannon-Wiener指数、物种丰富度指数和物种均匀度指数分析物种多样性和群落种类组成的相似程度,对渚碧礁大型底栖动物的群落结构进行了初步研究。结果表明:调查获得渚碧礁调查站大型底栖动物总种数314种,平均栖息密度为357.94个/m2,平均生物量为64.85g/m2;群落中主要的重要种或优势种为粗糙毛壳蟹(Pilodius scabriculus)和鼓虾(Alpheus spp.),但IRI指数相对较低;群落结构聚类分析和MDS标序表明,4个取样站的群落结构非常相似,Bray-Curtis相似性系数达到80%以上。

Based upon examination of material collected in 2002 from five sampling stations within the Zhubi Reef, Nanshan Islands, southern South China Sea, the main characters of the coral reef macrobenthic community were defined, using CLUSTER, MDS and DIVERSE functions of the software PRIMER. The results show that 314 macrobenthic species occurred in the stations, including 130 mollusc species, 110 crustaceans and 30 polychaetes. The dominant species were Pilodius scabriculus and Alpheus app., the IRis of the dominant species were low ; the structure of the macrobenthic communities in the stations 5 - 8 were very similar, and the Bray-Curtis similarity was up to 80%.