大庆库里泡浮游植物群落时空变化及其与环境因子的相关性

库里泡是黑龙江省大庆市重要的排污、泄洪湖库之一。近年来,由于大庆市生活及工业污水排放总量逐年增加,库里泡水体质量有所下降。为掌握库里泡浮游植物群落结构特征及水环境状况,于2019年春、夏、秋3季在库里泡共设置了13个采样点,对浮游植物群落及其与水环境变量的相关关系进行了研究。利用群落相似性分析(ANOSIM)检验浮游植物群落的组间及组内差异;采用相似性百分比(SIMPER)分析辨别对群落时空格局有显著影响的物种;通过冗余分析(RDA)确认环境变量及浮游植物优势种的生态分布特征,并对主要影响因子进行辨别。结果显示:研究期间共鉴定出浮游植物106种,隶属于6门8纲13目23科49属。库里泡的浮游植物群落组成为绿藻-硅藻型,而蓝藻、隐藻、甲藻、裸藻种类相对较少,占比仅为25%。其中,优势种有15种,主要为狭形纤维藻(Ankistrodesmus angustus)、四尾栅藻(Scenedesmus quadricauda)和梅尼小环藻(Cyclotella meneghiniana)等。ANOSIM和SIMPER分析结果表明,季节差异和生境差异对库里泡浮游植物群落结构的构建具有一定的驱动作用。RDA结果表明,影响库里泡浮游植物群落时空格局的主要环境变量为水温、总磷和总氮。营养状态指数评价结果显示,库里泡水质为中度富营养。经与近10年间的库里泡相关研究对比发现,库里泡水体浮游植物群落结构较为稳定,浮游植物优势类群略有改变。

Spatio-Temporal Changes of Phytoplankton Communities and Their Correlation with Environmental Factors in Kulipao Lake,Daqing City

Kulipao Lake is one of the important sewage and flood discharge lakes in Daqing City,Heilongjiang Province.In recent years,the total discharge of domestic and industrial sewage in Daqing City has increased,as well the water quality has declined.In order to understand the characteristics of phytoplankton community structure and state of water quality of Kulipao Lake,13 sampling points were settled in spring,summer and autumn of 2019,to study the correlation between phytoplankton community structure and its environmental factors.Analysis of community similarity (ANOSIM) was used to explore the differences between and within phytoplankton communities.The key species affecting the spatio-temporal pattern of the community were screened out by community similarity analysis (SIMPER).Redundancy analysis (RDA) was used to reveal the ecological distribution characteristics of phytoplankton community and identify the key influencing factors.The results showed that a total of 106 species of phytoplankton were identified during the survey,belonging to 49 genera,23 families,13 orders,8 classes,6 phyla.The community composition was mainly chlorophyta-diatom type,and the species of cyanobacteria,cryptophytes,dinoflagellates and gymnosperms were relatively few,accounting for only 25%.Among them,15 dominant species were mainly Cyclotella meneghiniana,Ankistrodesmus angustus and Scenedesmus quadricauda.ANOSIM and SIMPER analysis showed that seasonal and habitat differences had a certain driving effect on the spatio-temporal pattern of phytoplankton community in Kulipao Lake.The RDA showed that the main water environmental factors driving the spatiotemporal distribution of phytoplankton community in Kulipao Lake were water temperature,total phosphorus and total nitrogen.The comprehensive trophic level index evaluation showed that Kulipao water was moderately eutrophic.Compared with the related studies in Kulipao Lake in the past 10 years,it was found that the phytoplankton community structure in Kulipao Lake was relatively stable,and the dominant groups of phytoplankton changed slightly.