2014年冬季西太平洋雅浦海山与大洋海域大型浮游动物群落比较研究

2014年冬季对西太平洋雅浦Y3海山区和从西太平洋暖池区到黑潮源区之间的大洋海域的浮游动物进行了调查研究,分析了海山区和大洋海域大型浮游动物群落的物种组成、丰度和分布,并比较了两个海域大型浮游动物群落的差异,结合温度、盐度和叶绿素a浓度等环境因子数据,分析了海山对大型浮游动物群落的影响。结果表明,Y3海山区和大洋海域的大型浮游动物群落物种组成存在差异,二者的群落相似度系数为68.4%,两个海域的优势种/类群也不尽相同,海山区的优势种/类群是磷虾各期幼体、尖额磷虾和蛮𧊕,而大洋海域的优势种/类群分别是磷虾后期幼体、手磷虾、蛮𧊕、尖额磷虾和莹虾。大型浮游动物群落在海山区的平均丰度和最大丰度都要高于大洋海域,但海山区的生物多样性指数、均匀度指数和生物量占比都低于大洋海域,因而Y3海山对大型浮游动物群落的海山效应不明显。通过相关性分析和主成分分析结果可以看出,海山区的首要影响环境因子是盐度,而大洋海域则是温度;海山区和大洋海域的大型浮游动物丰度分别与200m层盐度和平均温度呈负相关关系,并且在两个调查海域均未发现大型浮游动物的丰度和生物量分布与叶绿素a浓度之间存在显著的相关关系。

COMPARATIVE STUDIES OF MACROZOOPLANKTON COMMUNITIES IN THE WESTERN PACIFIC OCEAN AND YAP SEAMOUNT AREA IN WINTER 2014

Zooplankton communities in Yap seamount Y3 area (the seamount area) and the western Pacific Ocean from the warm pool to the Kuroshio area (the ocean area) in winter 2014 were investigated. The species composition, abundance, and distribution of the macrozooplankton communities in the seamount area and the ocean area were studied. Differences between the macrozooplankton communities of the two areas were compared. Combined with the environmental factors such as seawater temperature, salinity, and chlorophyll a concentration, the effects of seamount on macrozooplankton community were analyzed. The results show that the species composition and dominant species/groups of macrozooplankton communities in the seamount area and the ocean area were different. The Sørensen coefficient of similarity between the two communities was 68.4%. The dominant macrozooplankton species/groups in the two areas were also different. Euphausiid lavae, Euphausia diomedeae and Lestrigonus spp. were the dominant species/groups in seamount Y3 sea area, while euphausiid post-lavae, Stylocheiron sp., Lestrigonus spp., Euphausia diomedeae, and Lucifer spp. were the dominant species/groups in the ocean area. The average and maximum abundance of macrozooplankton community in the seamount area were higher than those in the ocean area, but the Shannon-wiener index, Pielou evenness index and the proportion of biomass in the seamount sea area were lower than those in the ocean area. The "seamount effect" of seamount Y3 on macrozooplankton community was not obvious. Results of correlation analysis and principal component analysis show the principal environmental factor in the seamount sea area was seawater salinity, while that in the ocean area was seawater temperature. The abundances of macrozooplankton in the two areas were negatively correlated with seawater salinity of 200 m layer and average seawater temperature, respectively. Furthermore, there was no significant correlation between the abundance-biomass of macrozooplankton and the chlorophyll a concentration in the two sea areas.