<p>Ecological floating beds are an economically sustainable green technology that can effectively improve water quality. This study investigated the species and functional diversity of planktonic ciliates communities within the ecological floating beds of <i>Sesuvium portulacastrum</i>. The results showed that the abundance of planktonic ciliates was higher in spring and summer&#xa0;but lower in autumn and winter, with the lowest diversity indices observed in spring. Salinity was identified as the most influential environmental factor affecting community structure and was significantly correlated with all diversity indices. Among community traits, the presence of lorica was the strongest predictor of community structure, followed by feeding type. Most species within the community exhibited positive correlations, while negative correlations were primarily observed between the dominant genera <i>Tintinnopsis</i> and <i>Strombidium</i>. These genera displayed opposing patterns in response to environmental factors. Different ciliate groups exhibited distinct responses to nutrient levels, further highlighting the potential of ciliates as ecological indicators.</p>