江苏吴江市长漾湖浮游植物群落结构与水质评价

Community structure of phytoplankton and water quality evaluation in Lake Changyang,Wujiang,Jiangsu province

为掌握江苏吴江市长漾湖浮游植物群落结构及水质状况,于2011年7月-2012年6月进行了采样调查分析。结果显示:共检出浮游植物8门299种,其中绿藻门132种(占44.15%),硅藻门次之为66种(22.07%),蓝藻门48种(16.05%),优势种共30种,均为污染指示种。浮游植物生物量和数量分别为6.87～13.56 mg/L和1.46×106～23.15×106cells/L,生物量硅藻最高,而绿藻数量最多;浮游植物生物量季节变化表现为秋季>春季>夏季>冬季,而夏季数量最多,受滤食性鱼类影响,浮游植物变化规律与PEG模型有所差异。生物多样性和均匀度结果表明,浮游植物多样性较好,依其进行水质评价并参照污染指示种和浮游植物生物量,显示长漾水质在寡污和中污染间变化。

In order to study the community structure of phytoplankton and evaluate the water quality in Changyang Lake , an investigation had been conducted during July 2011 to June 2012. Results showed that 8 classes including 299 species had been found in the lake. Chlorophyta had 132 species （44.15% of the total species） , and baeillariophyta and cyanophyta had 66 species （22.07%） and 48 species （16.05%）, respectively. Thirty dominant species existed, and all of them were pollution indicators. The biomass and quantity of phytoplaukton ranged from 6. 87 mg/L to 13.56 mg/L and 1.46×106 eells/L to 23.15 x 106 cells/L, separalely. Chlorophyta was the largest in the quantity of phytoplankton. The maximum of biomass was Bacillariophyta instead of Chlorophyta. The biomass in the order of size was ： Autumn 〉 Spring 〉 Summer 〉 Winter, but the largest quantities of phytoplankton appeared in Summer. The seasonal succession of phytoplankton was slightly different from the PEG （ Plankton Ecology Group ） model because of filter - feeding fishes＇ grazing on zooplankton. Results showed that diversity and evenness of phytoplankton were in good status in the lake. The water quality was between oligotrophic and moderate pollution by assessing biodiversity index, pollution indicators and biomass.