陈桥东湖浮游植物群落结构与环境因子的关系

为研究陈桥东湖浮游植物群落的时空变化及其与环境因子之间的关系,于2017年1月、4月、7月和10月对陈桥东湖的4个样点进行采样调查.调查共发现浮游植物8门67属118种.其中绿藻种类最多,共47种,硅藻其次,共35种.浮游植物丰度变化为2.52～39.7×106 cells·L-1,平均丰度为8.54×106 cells·L-1,最高值出现在夏季.硅藻为陈桥东湖冬季的主要优势种类,绿藻和蓝藻则在夏、秋季节占优势.利用修正的卡尔森营养状态指数(TSIM)来评价水质,结果显示陈桥东湖整体呈现富营养化状况,且夏季水质最差,冬季相对较好,主要与人为干扰有关.浮游植物丰度与环境因子的相关性分析表明,蓝藻、绿藻与营养盐及水温极显著正相关(P0.01).金藻则与水温呈极显著负相关,与溶解氧呈极显著正相关(P0.01).典范对应分析(CCA)结果表明,溶解氧、水温、pH、总氮、透明度和化学需氧量是影响陈桥东湖浮游植物优势种变化的重要环境因子.

Relationship between phytoplankton community structure and environmental factors in Chenqiao East Lake

In order to study the spatio-temporal variations of phytoplankton community and its relationship with environmental factors in Chenqiao East Lake,four sites were sampled in January,April,July and October of 2017.During this period,118 phytoplankton species,from 8 phyla and 67 genera were recorded.The most diverse group was the green algae(47 spp,29 genera),followed by diatoms(35 spp.,15 genera).The abundance of the phyplankton was varied from 2.52×106 to 3.97×107 cells·L-1,the average abundance was 8.54× 106 cells·L-1,the highest value occurred in the summer.Bacillariophyta dominating during the winter,while Chlorophyta and Cyanophyta dominating during the summer and autumn.Using TSIMIndex to evaluated the water quality,the results showed that Chenqiao East Lake was eutrophication,with the worst in summer and the relatively good in winter,which was mainly related to human interference.Correlation analysis between phytoplankton abundance and environmental factors showed that,cyanobacteria and green algae were significantly positive correlation with nutrients and water temperature(P <0.01),Chrysophyta was significantly negative correlation with water temperature and significantly positive correlation with dissolved oxygen(P <0.01).Canonical correspondence analysis(CCA)results showed that dissolved oxygen,water temperature,pH,total nitrogen,transparency and Chemical oxygen demand are important environmental factors that affect the dominant species of phytoplankton in Chenqiao East Lake.