滇池春夏季浮游动物群落结构特征及与环境因子的关系

摘要

2013年3月和7月对滇池浮游动物群落结构及栖息环境进行调查，研究了滇池中浮游动物群落结构及与环境因子的关系。10个采样点共鉴定出浮游动物31种，轮虫类14种，占45．2％；枝角类9种，占29．0％；原生动物5种，占16．1％；桡足类3种，占9．7％。春季密度为1130ind／L，优势种为螺形龟甲轮虫（Keratella cochlearis）；夏季密度为1932ind／L，优势种为钟虫（Vorticella）和英勇剑水蚤（Cyclops strennus）。Pearson相关性分析结果显示，春季轮虫类密度与水温显著正相关，与CODMn显著负相关，夏季与水温、pH、DO显著正相关，与氮磷营养盐、电导率显著负相关；春季枝角类密度与TP显著负相关，夏季与氮磷营养盐、电导率显著正相关，与pH、DO、Chla显著负相关；桡足类密度与CODMn显著负相关，春季还与水温、DO、Chla、透明度、电导率呈显著正相关，原生动物与环境因子无显著相关性。浮游动物物种与环境因子的典范对应分析（CCA）结果表明：溶解氧、氮磷营养盐、叶绿素a、电导率是影响滇池浮游动物群落结构及分布的主要环境因子，其中春季的主要环境影响因子还有透明度、CODMn ，夏季水温和pH也是主要影响因子。%The relationship between zooplankton species composition and the environmental factors were studied in March and July 2013 in Dianchi Lake.A total of 31 zooplankton species were identified including 14 species of Ro-tifera (45. 2%),9 species of Cladocera (29%),5 species of Protozoa (16. 1%),and 3 species of Copepoda (9. 7%)in 10 sampling sites.The density of zooplankton was 1 130 ind/L and the dominant species was Keratella-cochlearis in spring;the density was 1932 ind/L and the dominant species was Vorticell and Cyclops strennus in summer.The Pearson correlation analysis revealed that water temperature was significantly positively related to roti-fers.Temperature was significant correlated to Rotifera.But chemical oxygen demand was negatively correlated to it in spring.Temperature,pH,and dissolved oxygen were significantly correlated to Rotifera.But nitrogen and phos-phorus nutrition,and conductivity were negatively correlated to it in summer.The total phosphorus was negatively related to Cladocera in spring.Nitrogen and phosphorus nutrition and conductivity were significantly correlated to it.But pH,dissolved oxygen,and chlorophyll were negatively correlated to it in summer.Chemical oxygen demand was negatively related to Copepoda,Temperature,dissolved oxygen,chlorophyll,and conductivity were significant-ly correlated to it in summer.According to the canonical correspondence analysis (CCA),the composition and dis-tribution of zooplankton were affected by dissolved oxygen,nitrogen and phosphorus nutrition,chlorophyll,conduc-tivity.Transparency and chemical oxygen demand were also the main environmental factors in spring.Water tem-perature and pH were also the fundamental environmental factors in summer.