吉安地区典型景观湖泊浮游植物群落特征及其与水环境因子的关系

Community structure of phytoplankton and its relationship with aquatic environmental factors in typical landscape lakes of Ji'an,Jiangxi Province

2012年8月至2013年7月,对吉安地区将军湖、龙湖、庐陵湖和挹翠湖4个景观湖泊水体浮游植物群落及其主要水环境因子进行了调查,并利用生物多样性指数法(Shannon指数H、Margalef指数D和Pielou指数J)和主成分分析(PCA)法分别对湖泊水质和水环境因子进行了评价。结果表明:4个湖泊共鉴定浮游植物7门82属163种,主要优势种为硅藻或绿藻;浮游植物细胞丰度呈季节性变化,秋夏居高,冬春季偏低,平均丰度变化范围为25.45×10~6~54.04×10~6cells·L^(-1);将军湖、龙湖、庐陵湖和挹翠湖的H值分别为1.26~2.08、1.82~2.61、2.27~2.62和1.10~2.32;D值分别为2.03~3.51、2.36~3.71、2.48~3.93和3.12~3.96;J值分别为0.45~0.69、0.59~0.80、0.67~0.77和0.50~0.84。综合评价结果显示,4个湖泊处于富营养化状态、中等污染水平。而对污染较重的庐陵湖水环境因子PCA分析结果表明,水温(WT)、溶解氧(DO)和总氮(TN)是影响小型封闭景观水体浮游植物群落变化的主要因素。建议对小型封闭景观水体进行必要的治理和生态修复。

From August 2012 to July 2013,phytoplankton communities and the main aquatic environmental factors were investigated in four landscape lakes（ Jiangjun Lake,Long Lake,Luling Lake and Yicui Lake） in Ji ＇an,Jiangxi Province. The water quality was evaluated by using biodiversity indexes（ Shannon index H,Margalef index D and Pielou index J）,and the water environmental factors were analyzed by principal components analysis（ PCA）. The results indicated that a total of 163 species of phytoplankton were identified,which belonged to 7 phyla and 82 genera. Phytoplankton species in four landscape lakes were mainly composed of Bacillariophyta and Chlorophyta. Phytoplankton cell abundance varied seasonally with values ranging from 25.45× 10^6 to 54. 04 × 10^6cells·L^（-1）,which were high in summer and autumn but low in winter and spring. In Jiangjun Lake,Long Lake,Luling Lake and Yicui Lake,the H value of phytoplankton was 1.26-2.08,1.82- 2.61,2.27- 2. 62 and 1. 10- 2. 32,respectively; the D value was 2. 03-3.51,2.36-3.71,2.48-3.93 and 3.12-3.96,respectively; the J value was 0.45-0.69,0.59-0.80,0.67- 0. 77 and 0. 50- 0. 84,respectively. Based on this investigation,it was considered that the four lakes were under eutrophic situation and at moderate pollution level. According to PCA of Luling Lake with relatively serious pollution,water temperature（ WT）,dissolved oxygen（ DO） and total nitrogen（ TN） were the most important environmental factors influencing the distribution of phytoplankton in small enclosed landscape water body. It is suggested that some necessary management and ecological remediation should be strengthened for the small closed landscape water.