Abstract We have determined how Crustacea, zebra mussels (Dreissena polymorpha), fish and nutrients affect the trophic state in mesocosms filled with water collected from the pelagic zone of a eutrophic lake. We hypothesized that the pool of nutrients would increase both directly due to the input of phosphorus and nitrogen and/or indirectly due to the introduction of animal biomass. We used trophic state indices based on the abundance and species structure of rotifers to assess changes in the trophic state in mesocosms. The role of small detritophages in rotifer communities increased as a result of treatments. Our results clearly demonstrated that D. polymorpha was able to reduce the trophic status of mesocosm waters as indicated by reduced rotifer trophic state indices regardless of interactions with other treatment factors. Contrary to our expectations, neither the nutrients added at the beginning of the experiment nor the introduction of crustaceans or fish affected the rotifer trophic indices.

中文翻译：

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使用轮虫营养状态指数显示水生生物和养分对中宇宙中水营养状态的影响

摘要 我们已经确定甲壳纲、斑马贻贝（Dreissena polymorpha）、鱼类和营养物质如何影响充满从富营养化湖泊的远洋区收集的水的中层世界中的营养状态。我们假设养分池将直接由于磷和氮的输入和/或由于动物生物量的引入而间接增加。我们使用基于轮虫丰度和物种结构的营养状态指数来评估中宇宙中营养状态的变化。由于治疗，小碎屑噬菌体在轮虫群落中的作用增加。我们的结果清楚地表明，无论与其他处理因素的相互作用如何，D. polymorpha 都能降低中宇宙水域的营养状态，如轮虫营养状态指数降低所表明的那样。