Laboratory of Protistology and Aquatic Ecology, Ghent University, Krijgslaan 281 (S8), 9000 Gent, Belgium.
Eur J Protistol. 2013 Nov;49(4):538-51. doi: 10.1016/j.ejop.2013.06.001. Epub 2013 Jul 23.
Temperate shallow meso- to eutrophic lakes can exist in one of two alternative states with contrasting foodwebs, referred to as the clear-water and the turbid state. We describe the planktonic ciliate communities of such lakes based on a survey of 66 northwestern European lakes. Ciliates were enumerated and identified to species level according to the quantitative protargol staining technique. Ciliate biomass was on average twice as high in the turbid than in the clear-water lakes. The ciliate communities were dominated by oligotrichs and protostomatids, and no differences in functional composition or α-diversity could be detected between turbid and clear-water lakes, although β-diversity tended to be higher in the latter. At the species level, however, community structure strongly differed between turbid and clear-water lakes, and several indicator species could be identified for the different lake categories. Variation partitioning showed that nutrient status did not explain ciliate community structure independent of the alternative states, while lake area was identified as an additional structuring factor for the ciliate communities. These results stress the importance of the ecosystem structure in shaping ciliate communities in temperate shallow lakes and suggest that nutrient status has little direct effect on ciliate community structure in such lakes.
温带浅中型到富营养化湖泊可以存在于两种截然不同的食物网替代状态之一，分别称为清水态和浊水态。我们根据对 66 个西北欧湖泊的调查，描述了这种湖泊的浮游纤毛虫群落。根据定量原银染色技术对纤毛虫进行了计数和分类鉴定。浊水湖泊中的纤毛虫生物量平均是清水湖泊的两倍。纤毛虫群落主要由寡毛类和原生动物门组成，在浊水和清水湖泊之间，功能组成或 α 多样性没有差异，但 β 多样性在后者中往往更高。然而，在物种水平上，浊水和清水湖泊的群落结构差异很大，并且可以为不同的湖泊类别确定几个指示物种。变异分割表明，营养状况并不能独立于替代状态解释纤毛虫群落结构，而湖泊面积被确定为纤毛虫群落的另一个结构因素。这些结果强调了生态系统结构在塑造温带浅型湖泊中纤毛虫群落的重要性，并表明营养状况对这种湖泊中纤毛虫群落结构的直接影响很小。
