中文摘要：

根据2011年7、11月和2012年2、5月胶州湾北部海域的调查数据，对该海域的浮游植物群落结构特征进行了分析。共鉴定浮游植物2门38属80种，其中硅藻占物种总数的88．75％。群落优势种组成表现出明显的季节演替，与历史资料比较，出现新的优势种波状石丝藻（Lithodesmium undulatum）和刚毛根管藻（Rhizosoleniasetigera）。浮游植物细胞丰度介于2．36～416．08×10^4cells／m^3，平均值为124．66×10^4cells／m^3，硅藻占总丰度的99．76％，季节变化呈现出明显的“双周期型”特征，细胞丰度低于历史数据。Shannon—Winner指数、Pielou均匀度指数和Margalef丰富度指数显示该海域浮游植物多样性总体较好，群落结构较稳定。

英文摘要：

Based on the investigational data of Jiaozhou Bay from 2011 to 2012, the characteristics of the phytoplankton community structure were analyzed. A total of 80 taxa belonging to 38 genera of 2 phyla were identified. Bacillariophyta was the main phytoplankton group, representing 88. 75% of the total species. The dominant species changed with different seasons, and different from historical data. Lithodesmium undulatum and Rhizosolenia setigera were the new dominant species. The seasonal variation of phytoplankton cell abundance was a typical double period type. The cell abundance of phytoplankton varied from 2.36 104cells/m3 to 416.08 104cells/m^3 with an average of 124.66 10^4cells/m^3 which was lower than historical data. Bacillariophyta accounted for 99.76% of total abundance. The analytic results of Shannon-Wiener index, Pielou evenness index and Margalef richness index showed that the diversity was well and the community structure was stable in the area.