长江口碎波带浮游植物群落结构特征

2009年5月至2010年4月,按月对长江口碎波带浮游植物群落结构和环境因子进行调查。采集到浮游植物64属123种,主要由硅藻、绿藻和蓝藻组成。主要优势种为小环藻,常见种为硅藻门的直链藻（Melosira sp.）、中肋骨条藻（Skeletonema costatum）、膜状舟形藻（Navicula membranacea）,蓝藻门的小颤藻（Oscillatoria tenuis）、小席藻（Phormidium tenue）以及绿藻门的小球藻（Chlorella vulgaris）。浮游植物丰度在8.07×10^4cells/L～1.39×10^6cells/L之间,2009年8月最高,12月最低。浮游植物群落在7—8月份主要由蓝藻组成,其他月份主要由硅藻组成。统计分析细胞丰度与环境因子相关性显示：pH值与绿藻门和蓝藻门的细胞丰度显著负相关（P〈0.05,r〈0）,透明度与绿藻门和蓝藻门的细胞丰度显著正相关（P〈0.05,r〉0）;温度与硅藻门的细胞丰度显著负相关（P〈0.05,r〈0）。

Ecological features of phytoplankton community in the surf zones of the Yangtze River estuary

Community structure of phytoplankton and environmental factors were collected monthly in the surf zones of the Yangtze River estuary from May 2009 to April 2010. 123 species from 64 genera were identified in the surf zones of the Yangtze River estuary. The main dominant species were Melosira sp.,Skeletonema costatum,Navicula membranacea,Oscillatoria tenuis and Phormidium tenue.Chlorella vulgaris of Chlorophyta was also common in the dominant species. The abundance of phytoplankton was from 8. 07 × 10^4to1. 39 × 10^6 cells /L,the highest in August,and the lowest in December. The phytoplankton was mainly constituted of Cyanophyta in July and August,and in other months was constituted of Bacillariophyta. The correlation analysis between cell abundance and environmental factors showed that the pH value had a significant negative correlation with the cell abundance of Chlorophyta and Cyanophyta（ P〈0.05,r〈 0）,the transparency had a significant correlation with the cell abundance of Chlorophyta and Cyanophyta（ P〈0.05,r〉 0）,the temperature showed the significant negative correlation with the cell abundance of Bacillariophyta（ P〈0. 05,r 〈0）.