云贵高原湖泊夏季浮游植物组成及多样性

Phytoplankton community structure and biodiversity in summer Yunnan-Guizhou Plateau lakes

浮游植物是水生生态系统中重要的初级生产者,对维持水生态系统的平衡起着十分重要的作用.根据2008年云贵高原湖泊丰水期浮游植物调查数据,系统地分析了云贵高原13个湖泊中浮游植物的种群密度、生物量、组成及其多样性.云贵高原13个湖泊中共鉴定出浮游植物7门109种(绿藻52种、蓝藻23种、硅藻20种、其他14种).13个湖泊浮游植物Shannon-Wiener指数在0.5-2.2之间,其值大小与单个环境因子无显著相关.相关分析发现浮游植物总量与总氮、总磷、CODMn、硝态氮含量显著正相关,物种丰富度与总氮、总磷(0.1mg/L范围内)、CODMn含量亦显著正相关.另外,研究也发现各湖泊间浮游植物组成的相似性与各湖泊间营养状态差异显著负相关.由此可见,湖泊的营养状态不仅影响浮游植物的总量、组成以及物种丰富度,而且也影响各湖泊物种组成的相似性.

Phytoplankton is very important to keep the balance of aquatic ecosystems as one of primary producers.In the present study,phytoplankton in 13 lakes of Yunnan-Guizhou Plateau were investigated during the summer June–August of 2008,and phytoplankton abundance,biomass,community structure and biodiversity were analyzed.A total of 109 taxa （52 green algae,23 cyanobacteria,20 diatoms,14 others） were found in the lakes.Shannon-Wiener indexes of phytoplankton in the 13 lakes were ranged from 0.5 to 2.2,which were not significant correlations with any single factor.Furthermore,phytoplankton abundance and biomass were obviously correlated with TN,TP,CODMn and NO3-N,and species richness was remarkably correlated with TP （0.1mg/L）,TN and CODMn.In addition,there was significantly negative correlation between Soreson similarity of community structure and variation of trophic states in the 13 lakes.Our results indicated that trophic states of lake can influence phytoplankton abundance,biomass,species richness and Soreson similarity of community structure.