Environmental factors and dispersal can influence the structure of biological communities. Their effects can depend on the functional features of the species in the community. Since species belonging to the same trophic level, such as phytoplankton, may show functional differences, we investigated whether the effects of environment and dispersal differ among phytoplankton species from different functional groups. We analyzed data from a rainy and a dry period in 30 reservoirs in a subtropical region. In both periods, the environment as well as high and limited dispersal influenced the metacommunity structure. The functional groups had a low correspondence in their response to both dispersal and environment. Our results showed that the influence of the processes underlying the structure of the metacommunities, such as species sorting (environment influence), mass effect (high dispersal), and neutral dynamics (limited dispersal), depended on the functional characteristics of the organisms and could vary even among species of the same trophic level. These findings suggested that species at the same trophic level could not be considered ecological equivalents. This paper includes a Portuguese and Spanish version of the abstract in the online resources.

环境因素和扩散可以影响生物群落的结构。它们的影响可能取决于群落中物种的功能特征。由于属于同一营养级的物种（例如浮游植物）可能表现出功能差异，因此我们研究了来自不同功能群的浮游植物物种之间环境和扩散的影响是否存在差异。我们分析了亚热带地区 30 个水库的雨季和旱季数据。在这两个时期，环境以及高度和有限的分散都影响了元群落结构。功能组对分散和环境的响应的一致性较低。我们的结果表明，元群落结构背后的过程的影响，例如物种分类（环境影响）、质量效应（高扩散）和中性动力学（有限扩散），取决于生物体的功能特征，并且可以即使在同一营养级的物种之间也存在差异。这些发现表明，同一营养级的物种不能被视为生态等同物。本文在在线资源中包含葡萄牙语和西班牙语版本的摘要。