Does phosphite accelerate the phosphorus cycle in freshwater ecosystems?

Abstract

Phosphite is supposed to an essential compound for the origin of early life, and exist as the main form of phosphorus (P) in the P cycle of ancient anoxic marine environments. Recent researches have discovered the presence of phosphite in contemporary aquatic ecosystems, considering its utilization by microorganisms via assimilatory and dissimilatory phosphite oxidation, as well as the indirect photooxidization to orthophosphate by ultraviolet light, which indicate the potential contribution of phosphite for P cycle in modern earth. Given its high solubility, phosphite is believed to expedite P transformations in freshwater aquatic environments, particularly in lacustrine systems. Compared to oceans, these systems have shallower waters, which favor the rapid transport of released phosphite from reducing sediments to surface water. This is especially significant if the sediment is a major production site for phosphite, indicating that its role in the P cycle might have been previously understated.