Structure of phytoplankton community and its relationship with environmental factors at the estuary of Maixi River in Baihua Reservoir,Guizhou Province

2009年7月至2010年6月, 以每月一次的频率对百花湖(水库)麦西河河口浮游植物群落结构和环境因子进行调查.监测到浮游植物66种(属), 浮游植物主要由绿藻、硅藻和蓝藻组成, 夏秋季湖泊假鱼腥藻(Pseudanabaena limnetica)为优势浮游植物, 而冬春季梅尼小环藻(Cyclotella meneghiniana)为主要优势藻.浮游植物丰度在1.17×104-3.35×107cells/L之间, 2010年4月最低, 2009年7月最高, 浮游植物种群在4-9月主要由蓝藻组成, 冬季由硅藻和甲藻组成.运用典型对应分析研究结果表明:温度是影响麦西河河口浮游植物群落结构动态变化的最主要环境因子, 其次为营养盐;蓝藻的大部分种类和裸藻受水温和浊度等影响较大, 而硅藻和绿藻的大部分种类受氮磷营养盐浓度影响较大。;Phytoplankton and environmental factors at the estuary of Maixi River in Baihua Reservoir were investigated monthly from July 2009 to June 2010.Results showed that there were 66 species(genus),which were mainly composed of the chlorophyta,ba-cillariophyta and cyanobacteria.The phytoplankton community was dominated by Pseudanabaena limnetica in summer and fall and by Cyclotella meneghiniana in winter and spring.The abundance of phytoplankton ranged from 1.17×104 to 3.35×107 cells/L.The minimum phytoplankton abundance occurred in April of 2010,and the maximum occurred in July of 2009.The phytoplankton abundance composition was dominated mainly by cyanobacteria from April to September, but by bacillariophyta and pyrrophyta from October to March.Canonical correspondence analysis showed that temperature was the most important driving factor in regulating the composition and feature of phytoplankton community at the estuary.Nitrogen and phosphorus were the second important driving factors for the structure of phytoplankton community.Euglenophyta and a majority of cyanobacteria were affected by water tempera-ture and turbidity,but chlorophyta and bacillariophyta were affected by the concentrations of nitrogen and phosphorus among these environmental factors.