Occurrence of a single-species cyanobacterial bloom in a lake in Cyprus: monitoring and treatment with hydrogen peroxide-releasing granules

Abstract Background Excess loads of nutrients finding their way into waterbodies can cause rapid and excessive growth phytoplankton species lead to the formation cyanobacterial harmful algal blooms (cyano-HABs). Toxic cyanobacteria produce a broad range bioactive metabolites, some which are known as cyanotoxins. These metabolites negatively impact ecosystem, human animal health, thus presence needs be closely monitored mitigated. This study aimed monitor St. George Lake (Athalassa National Forest Park, Cyprus) for its water quality characteristics, initiate new methodology control bloom that occurred in lake during summer 2019, by comparing hydrogen peroxide treatment with novel metallic granules source peroxide. Results monitoring showed pH, salinity, total dissolved solids conductivity varied throughout year, concentration was high, indicating eutrophic lake. The cyanobacterium Merismopedia sp. bloomed between June September comprising up 99% biovolume. microcystin synthase encoding gene ( mcy B, mcyE) documented, however microcystins were not detected tandem mass spectroscopy. Treatment liquid concentrations 1 5 mg L −1 had no effect on phycocyanin fluorescence (Ft) quantum yield PSII (Fv/Fm) an ineffective dense (1 million cells mL ± 20%). Metallic tested H 2 O releasing capacity water, showing CaO released higher therefore have better mitigation efficiency than MgO granules. Conclusion present highlights importance several parameters conclude different actions taken limit eutrophication catchment area. findings demonstrated testing genes involved cyanotoxin production may sufficient follow cyanotoxins it should accompanied analytical confirmation. experiments indicated slow release from alternative when applied appropriate doses, but further investigation is needed before at field. Graphic