北部湾底拖网软体动物的种类组成及其环境影响

Species composition of trawling mollusk in Beibu Gulf and its environmental effect

2006年和2007年,厦门大学海洋与环境学院租用中科院南海所实验2号科考船,首次对北部湾进行全面的生态综合考察。生物组对16个站位进行四个季度的底拖网,共获得底拖网软体动物125种,其中双壳类59种,腹足类56种,头足类9种,掘足类1种。地理分布上,软体动物丰度北部最高,中部次之,南部最低,分别为42.1个/站、14.0个/站和10.7个/站。北部明显高于南部。生物-环境分析表明盐度在四个季度中均是影响软体动物组成的主要环境因子,但除了冬季的相关值较高外,其他季节的相关值均低于0.4,说明盐度对底拖网软体动物组成的影响不显著。优势种波纹巴非蛤(Paphia undulata)丰度与溶解氧、粘土和叶绿素含量呈显著正相关;赛氏毛蚶(Scapharc a satowi)丰度与水深、底盐呈显著负相关,与溶解氧和叶绿素呈极显著正相关;浅缝骨螺(Murex trapa)丰度与水深、底盐呈显著负相关,与底温、粘土和叶绿素含量呈显著正相关。

The comprehensive ecological research was carried out in Beibu Gulf on a scientific surveying ship during 2006-2007 for the first time.Bottom trawl surveys were taken place in 16 stations in four seasons and 125 species of mollusk,including 59 species of bivalve,56 gastropod,9 cephalopod and 1 scaphopod were obtained.Geographically,the abundance of mollusk in the north of Beibu Gulf was much higher than those in the center and the south.Bio-environment analysis showed that salinity exerted a key factor on the species composition of mollusk.However,the correlation coefficients in all seasons except for winter were lower than 0.4,revealing that the influence of salinity on trawling mollusk was not significant.Further more,the abundance of Paphia undulata had a significant positive correlation with DO,clay and chlorophyll content.The abundance of Scapharca satowi had a significant negative correlation with the depth of water and bottom salinity,as well as a very significant positive correlation with DO and chlorophyll.The abundance of Murex trapa had a significant negative correlation with the depth of water and bottom salinity,as well as a significant positive correlation with the bottom temperature,clay and chlorophyll.