Document Type
Article
Publication Date
10-28-2014
Keywords
phosphorus, redox chemistry, phosphonates, element cycling, biogeochemistry
Digital Object Identifier (DOI)
https://doi.org/10.1073/pnas.1408134111
Abstract
The element phosphorus (P) controls growth in many ecosystems as the limiting nutrient, where it is broadly considered to reside as pentavalent P in phosphate minerals and organic esters. Exceptions to pentavalent P include phosphine—PH3—a trace atmospheric gas, and phosphite and hypophosphite, P anions that have been detected recently in lightning strikes, eutrophic lakes, geothermal springs, and termite hindguts. Reduced oxidation state P compounds include the phosphonates, characterized by C−P bonds, which bear up to 25% of total organic dissolved phosphorus. Reduced P compounds have been considered to be rare; however, the microbial ability to use reduced P compounds as sole P sources is ubiquitous. Here we show that between 10% and 20% of dissolved P bears a redox state of less than +5 in water samples from central Florida, on average, with some samples bearing almost as much reduced P as phosphate. If the quantity of reduced P observed in the water samples from Florida studied here is broadly characteristic of similar environments on the global scale, it accounts well for the concentration of atmospheric phosphine and provides a rationale for the ubiquity of phosphite utilization genes in nature. Phosphine is generated at a quantity consistent with thermodynamic equilibrium established by the disproportionation reaction of reduced P species. Comprising 10–20% of the total dissolved P inventory in Florida environments, reduced P compounds could hence be a critical part of the phosphorus biogeochemical cycle, and in turn may impact global carbon cycling and methanogenesis.
Rights Information
Was this content written or created while at USF?
Yes
Citation / Publisher Attribution
Redox Chemistry in the Phosphorus Biogeochemical Cycle, v. 111, issue 43, p. 15468-15473
Link to the publisher: https://doi.org/10.1073/pnas.1408134111
Scholar Commons Citation
Pasek, Matthew A.; Sampson, Jacqueline M.; and Atlas, Zachary, "Redox Chemistry in the Phosphorus Biogeochemical Cycle" (2014). School of Geosciences Faculty and Staff Publications. 1492.
https://digitalcommons.usf.edu/geo_facpub/1492
