胶州湾大型底栖软体动物物种多样性研究

Species diversity of macrobenthic mollusk fauna in Jiaozhou Bay, Shandong

1998年2月至2004年11月,共7年27个航次对胶州湾10个站进行综合调查,研究了其大型底栖软体动物的多样性现状(菲律宾蛤仔(Ruditapesphilippinarum)除外)并探讨其成因。结果表明:在胶州湾共发现62种底栖软体动物,优势种是滑理蛤(Theoralubrica)和豆形胡桃蛤(Nuculafaba)。从1998年至2004年期间物种多样性指数(H′)年际间波动幅度不大,且无明显的规律性变化;但季节变化明显,秋季和冬季较高,春季和夏季较低。物种均匀度指数(J)则为秋季最高(0.87),夏季最低(0.58)。物种丰富度指数(D)除夏季相对较低(1.82)外,其他三个季节差别不大。

Macrobenthic mollusk is one of the common marine benthic groups in the Jiaozhou Bay, which plays a very important role in food chains in the area. There has been much ecological research on macrobenthos of Jiaozhou Bay, but few studies on the species diversity of macrobenthic mollusk in detail. Based on the data collected from ten sampling stations from Febuary 1998 to November 2004, we studied the species diversity of macrobenthic mollusk fauna. Sampling was conducted in spring （May）, summer （August）, autumn （November）, and winter （February）, using a 0.1 m2 grab and then preserving samples in 75% alcohol. We identified, counted, and weighed the samples. Because of the large-scale aquaculture of Ruditapes philippinarum on the edge of the bay, it was difficult to distinguish natural populations from cultured ones, so this species was not included in the present study. A total of 62 species were found, of which the dominant species were Theora lubrica and Nucula faba. Common species were Moerella jedoensis, Raetellops pulchella, Eocylichna cylindrella, Nassarius succinctus, Cycladicama tsuchii, and Moerella iridescens. The Shannon-Wiener index （H′） showed no remarkable fluctuation during 1998 to 2004, but demonstrated distinct seasonal variations： the average he indices were higher in autumn and winter than in spring and summer. Pielou＇s evenness index （J） peaked in autumn （0.87）, and was lowest in summer （0.58）. The species richness index （D） was relatively lower in summer （1.82）, but no remarkable difference existed in other seasons.