Efficiency of phosphorus accumulation by plankton, periphyton developed on submerged artificial substrata and metaphyton: in-situ observation in two shallow ponds

Phosphorus overenrichment of shallow ponds prevailing in wetlands leads to their eutrophication causing the collapse of those vulnerable habitats. The potential of phosphorus accumulation by periphyton developed on artificial substrata has been investigated in two shallow ponds (Baracka and Siroki Rit) in northwest Serbia and compared to the same ability of plankton and metaphyton. The periphyton substrate carrier has been submerged from May to October. Both continuously (CS) and monthly developed (MS) periphyton were sampled. Autotrophic component of all investigated communities has been qualitatively assessed. Maximum accumulation of only 14.7 mg TP/m2 was recorded in three-month exposed periphyton CS. MS exposed from July to August reached maximal 12.7 mg TP/m2. Plankton community that was characterized by more diverse and abundantly developed algal component was more effective in phosphorus accumulation (0.7 mg/g dry weight) in comparison with dominantly inorganic and diatom-dominated periphyton in Baracka. Unstable conditions caused by recent revitalization (dredging organic matter and mud from pond basin—redigging) as well as rapid desiccation of Siroki Rit disabled making an unambiguous conclusion about the efficiency of phosphorus accumulation among different communities, but suggested slight potential of phosphorus harvesting by metaphyton in this pond. Due to the shorter exposure time that brings the reduced risk of unpredictable changes in the ecosystem, as well as the considerable amount of accumulated phosphorus, large-scale application of one-month exposed periphyton developed on artificial substrates would be more advisable for phosphorus harvesting in nutrient affected shallow ponds.