大亚湾夏、冬浮游植物群落结构与环境因子

The Characteristics of Phytoplankton Community Structure and the Relationship With Environmental Factors of Daya Bay in Summer and Winter

根据2015-08和2015-12大亚湾海域的调查数据,对大亚湾浮游植物种类组成、丰度分布、多样性及与环境因子的关系等进行分析。结果显示:夏冬两季共鉴定出浮游植物5门39属102种,其中硅藻70种,甲藻27种,金藻和绿藻分别为2种,蓝细菌1种。浮游植物丰度夏季波动范围为(0.80～42.43)×10~6个/m^3,均值为10.70×10~6个/m^3;冬季波动范围为(0.13～43.80)×10~6个/m^3,均值为7.24×10~6个/m^3;浮游植物丰度组成夏季以硅藻为主,占总丰度的97.51%,冬季则以金藻和蓝细菌为主,占97.41%。夏季优势种为中肋骨条藻(Skeletonema costatum)、柔弱拟菱形藻(Peseudo-nitzschia delicatissima)和菱形海线藻(Thalassionema nitzschioides);冬季优势种为球形棕囊藻(Phaeocystis globosa)和束毛藻(Trichodesmium sp.)。冗余分析显示,影响大亚湾浮游植物分布的关键环境因子,夏季为透明度、氮磷比、温度和盐度,冬季为盐度、pH、温度和亚硝氮。

Two surveys were conducted at nineteen stations in Daya Bay in the South China Sea in August and December 2015, the species composition, abundance distribution and diversity of phytoplankton in Daya Bay, and the relationships with environmental factors were investigated.The results showed that 5 phyla, 39 genera and 102 species, including 70 diatom species, 27 dinoflagellate species and 3 other species (chlorophyte, chrysophyta and Cyanobacteria) were identified.The range of phytoplankton abundance in summer was 0.80×10 ^6 to 42.43×10 ^6 cells/m^ 3 , mean value was 10.70×10^ 6 cells/m ^3 .The range of phytoplankton abundance in winter was 0.13×10^ 6 to 43.80×10 ^6 cells/m^ 3 , mean value was 7.24×10^ 6 cells/m^ 3 .The composition of phytoplankton abundance in summer was dominated by diatoms, which contributed 97.51% to the total abundance average.While in winter, the composition of phytoplankton abundance was dominated by chrysophyta and Cyanobacteria, accounting for about 97.41%.The dominant species were Skeletonema costatum , Peseudo-nitzschia delicatissima and Thalassionema nitzschioides in summer, and those were Phaeocystis globose and Trichodesmium sp.in winter.The RDA indicated that the key environmental factors influenced phytoplankton assemblages in summer were transparency, Nitrogen phosphorus ratio, water temperature and salinity, while salinity, pH, water temperature and nitrite nitrogen (NO - 2 -N) played key roles in winter.