Effects of Algal Utilization of Dissolved Organic Phosphorus by Microcystis Aeruginosa on Its Adaptation Capability to Ambient Ultraviolet Radiation

Phosphorus (P) plays an important role in eutrophication and algal adaptation to environmental stresses; therefore, a better understanding of the impact P is essential control cyanobacterial bloom. In this study, Microcystis aeruginosa treated with 5 h ambient irradiation culture medium different availabilities dissolved organic (DOP) matter (DOM) explore physiological responses. Compared photosynthetically active radiation (PAR), UV-A UV-B exerted oxidative stresses has inhibitive effects on growth photosynthesis M. aeruginosa. However, had strong capability, negative UV can be alleviated DOM addition DOP-rich medium. The waters mainly achieved through hydrolysis DOP metabolism inorganic (DIP), utilization behaviors might greatly affect capability. without DOM, great inactivation alkaline phosphatase (APase) after could result worse affinity for DOP, slower uptake lower cellular quota. Consequently, demand not satisfied processes, including decreasing UV-induced damages promoting self-repair. act as antioxidant significantly decrease APase UV-radiated by M.aeruginosa treatments promoted its adaptation, such enhanced production photosynthetic pigments, increased superoxide dismutase (SOD) activity, recovery efficiency, etc. Overall, our findings indicate close relationship between typical cyanobacteria DIP-limited DOP-enriched natural waters.