2010年夏季雷州半岛沿岸海域浮游动物群落结构特征

2010年7月对雷州半岛海岸带的浮游动物群落结构及相关环境因子进行了调查,共鉴定出浮游动物87种和34类浮游幼体,其中原生动物4种,占总种类数的4.6%;腔肠动物20种,占总种类数的23.0%;介形类1种,占总种类数的1.1%;枝角类2种,占总种类数的2.3%;桡足类37种,占总种类数的42.5%;十足类2种,占总种类数的2.3%;毛颚动物7种,占总种类数的8.0%;被囊动物6种,占总种类数的6.9%;浮游软体动物8种,占总种类数的9.2%。优势种有13种和3类浮游幼体,孔雀强额哲水蚤和小毛猛水蚤是该海域重要的优势种群,几乎在全海域均为优势种,桡足类幼体为全海域优势类群。半岛沿岸海域浮游动物种类数由近岸往远岸逐渐增多,浮游动物丰度分布则相反。浮游动物种类数由多到少的顺序为东北部、东南部、西北部和西南部、南部,丰度由大到小的顺序为西北部、西南部、东北部、东南部、南部,生物量由大到小的顺序为东北部、西南部、西北部、东南部、南部,浮游动物丰度和生物量的平面分布反映了人类对海岸带开发利用的活动概貌。多样性指数和均匀度平均值分别为2.96和0.57。相关分析表明:浮游动物丰度与水温、细菌总数、浮游动物生物量均呈极显著的正相关关系,与磷酸盐呈显著的负相关关系;浮游动物生物量与TOC、细菌总数、叶绿素a、浮游植物丰度均呈极显著的正相关关系,与pH呈显著的正相关关系,与盐度呈显著的负相关关系。

Zooplankton community in the coastal zone of Leizhou Peninsula in summer 2010

We investigated the community structure of zooplankton and the associated environmental factors in the coastal area of Leizhou Peninsula, Guangdong Province, in the summer of 2010. A total of 87 species of zooplankton and 34 species/assemblages of planktonic larvae were identified. Among which, Copepoda (37 species) was the most abundant, accounting for 42.5% of all species, followed by Coelenterata (20, 23.0%), molluscs (8, 9.2%), Chaetognatha (7, 8.0%), Tunicata (6, 6.9%), Protozoa (4, 4.6%); Cladocera and Decapoda (2 each, 2.3%) and 1 species of Ostracoda (1.1%). The dominant species included 13 species of zooplankton and 3 assemblages of planktonic larvae. Copepod larvae were the only dominant assemblages that spread throughout the coastal area. Two copepods, Pavocalanus crassirostris and Microsetella norvegica, were the important dominant species in almost the entire coastal area. Zooplankton species richness increased from landward zone to seaward zone, but the abundance decreased from landward zone to seaward zone. Species richness was highest in the northeast area, followed by the southeast, northwest, southwest and south areas in sequence; the highest zooplankton abundance was found in the northwest area, followed by the southwest, northeast, southeast and south areas; and the highest zooplankton biomass was obtained in the northeast area, followed by the southwest, northwest, southeast and south areas. The horizontal distributions of zooplankton abundance and biomass corresponded well with human activities in the development and utilization of coastal zones. The average diversity index and evenness of species were 2.96 and 0.57 respectively. Correlation analysis indicated that zooplankton abundance was positively correlated with water temperature, total bacterial density and zooplankton biomass, negatively correlated with phosphate; Zooplankton biomass was positively related to TOC, total bacterial density, Chl a, phytoplankton cell abundance and pH, negatively related to salinity.