Effects of floating bed plants on remediation of eutrophic ponds and cultured species of Cyprinus carpio

Abstract

In recent decades, cyanobacterial blooms have emerged as a major constraint on the sustainable development of freshwater aquaculture. Due to their capacity for biological self-purification, ecological floating beds have been widely utilized in the remediation of eutrophic water bodies. However, most existing studies have focused on the nutrient removal capacities of floating bed plants, with limited attention to their effects on algal community dynamics. In this study, three common aquatic plants—Eichhornia crassipes, Pistia stratiotes, and Ipomoea aquatica—were selected to investigate their overall effects on eutrophic pond remediation. All three species exhibited good tolerance to cyanobacterial blooms and significantly enhanced the anti-oxidative stress response of Cyprinus carpio. The cyanobacterial inhibition rates were 87.92 %, 70.07 %, and 96.32 %, respectively, whereas the relative abundance of green algae increased, most notably with I. aquatica. It is speculated that, in addition to plant-derived allelochemicals, toxin-degrading bacteria from the phyla Proteobacteria, Bacteroidetes, Myxococcota, and Bdellovibrionota may have contributed to the suppression of cyanobacteria. These findings improve understanding of the ecological roles of different floating bed plants in eutrophic pond restoration and offer a theoretical basis for species selection and future application of floating bed systems in aquatic ecosystem management.