南麂列岛邻近海域贝类生态分布的初步研究

Preliminary study on the distribution of mollusca ecology in sublittoral area of Nanji Islands

对南麂列岛邻近海域贝类生态分布的初步研究表明，在该海域共发现贝类４２种，广温广布种占５２．４％，亚热带种占２８．５％，热带种和暖温带种各占１１．９％和７．１％。优势种有江户明樱蛤Ｍｏｅｒｅｌａｊｅｄｏｅｎｓｉｓ、圆筒原盒螺Ｅｏ－ｃｙｌｉｃｈｎａｃｙｌｉｎｄｒｅｌａ、经氏壳蛞蝓Ｐｈｉｌｉｎｅｋｉｎｇｌｉｐｉｎｉ等。春、秋两季平均生物量为４．４０ｇ／ｍ２，平均栖息密度为５７．２６个／ｍ２，数量分布不均匀，并有明显季节变化。种类和数量变动与海流、温度、盐度、潮流、底质等因子有关。

otal 42 species of mollusca were identified in the sublittoral area of Nanji Islands. Among these Moerella jedosensis (Lischke), Eocylichna cylindrella (A.Adams), Philine kinglipim Tchang are dominant species. Most species are eurytropic species, occupying 52 4%, and subtropic species, tropic species and warm temperate species ocupy 28.5%, 11 9% and 7 1% respectively. Biomass and density vary with seasons obviously. Their average are 4 40 g/m 2 and 57 26 ind/m 2 respectively in spring and autumn. Moreover, species compasition and distribution of biomass are relative to tidal current, salinity, seabed sediment factors and so on.