昌黎生态监控区夏季浮游植物群落年际变化特征分析

Yearly Changes of Phytoplankton Community in the Ecology-monitoring Area of Changli,Hebei in Summer

为研究昌黎生态监控区夏季浮游植物群落结构特征及其与环境因子关系，采用2005～2013年夏季（8月）昌黎生态监控区海域浮游植物及环境因子的监测资料，基于ArcGIS10．0和Canoco软件平台，运用典范对应分析方法，对浮游植物群落结构进行分析．结果表明，近9a共鉴定出浮游植物3门23科39属105种，其中，硅藻门16科32属90种，占浮游植物总数的85．7％；甲藻门共6科6属14种，占总种类数的13．3％；金藻门1种．各年的优势种存在很大差异，按照优势度l，值的大小包括辐射圆筛藻（Coscinodis cusradiatus）、柔弱角毛藻（Coscinodiscus debilis）、笔尖根管藻（Rhizosolenia styliformis）、柏氏角管藻（Cerataulina bergoni）、威氏圆筛藻（Coscinodiscus wailesii）、海链藻（Thalassiosira sp．）、三角角藻（Ceratium tripos）、洛氏角毛藻（Coscinodiscus wailesii）、中肋骨条藻（Ceratium tripos）等．夏季细胞丰度年际变化较大，呈现逐渐降低的趋势．浮游植物的多样性指数H’值介于0．015～3．889，均匀度指数J值介于0．009～1，年际变化幅度较小；各站位间物种分布不均匀，优势种较少且优势度较大．对浮游植物群落与环境因子进行典范对应分析（CCA），结果表明影响夏季浮游植物群落结构变化的环境因子包括水温、营养盐（磷酸盐、硝酸氮、氨氮）、盐度等，且是各个环境因子相互作用的结果．

Based on the investigation of phytoplankton and water body nutrient concentration in the ecology-monitoring area of Changli in summer from 2005 to 2013, the phytoplankton community structure was analyzed. The result showed that in recent 9 years, 3 phyla including 23 families, 39 genera and 105 species of phytoplankton were identified, in which 85.7% were diatoms and 13.3% were dinoflagellate. Only one species was found belonging to golden algae. There was great difference in dominant species among different years. According to the value of dominance, there were Cosclnodiscus radiatus, Coscinodiscus debilis, Rhizosolenia styliformis, Cerataulina bergoni, Coscinodiscus wailesii, Thalassiosira sp. , Ceratium tripos, Chaetoceros lorenzianus, Skeletonema costatum. The cell abundance was decreased yearly. The Shannon-Wiener index of phytoplankton community ranged from 0. 015 to 3. 889, and the evenness index ranged from 0. 009 to 1, which showed little yearly change. And phytoplankton species were unevenly distributed among the 19 sites, there were relatively low amount of dominant species, but the dominance was relatively high. Canonical Correspondence Analysis （CCA） results of the phytoplankton community and its environmental factors showed that the environmental factors influencing the change of phytoplankton community structure in summer included water temperature, nutrients （TP, TN and NO3^- -N, NH4^＋ -N） and salinity, and the structural change was the result of the interactions of different environmental factors.