Phosphorus liberation by aquatic microorganisms

UNCW Author/Contributor (non-UNCW co-authors, if there are any, appear on document)
Stephen Gill (Creator)
The University of North Carolina Wilmington (UNCW )
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Abstract: The conventionally accepted route for cycling of inorganic phosphorus (P) was previously thought to be the long-term processes of abiotic physical and chemical weathering and subsequent physical exchange reactions with minerals. The ability of microorganisms to influence the liberation of labile P, from otherwise insoluble or sparingly soluble sources, in aquatic environments has been shown here to be capable of supporting appreciable biomass. The causal agents bringing about P liberation within the microcosm systems employed in this investigation were organic acids, principally gluconic acid, and [H+] ions. The effects of chelation by organic acids as opposed to dissociation purely as a result of protonation were addressed and biologically inoculated microcosms yielded significantly more labile P than would be anticipated by the corresponding change in pH alone. Maximal rates of liberation of P of up to 320 ┬Ámol P g-1 day-1 were observed. Acid production and the subsequent liberation of otherwise refractory forms of P appeared to be an active process as it was not solely dependent on biomass, implying that organic acid production was either selective or that microbial population shifts occurred as a response to P limitation.

Additional Information

A Thesis Submitted to the University of North Carolina at Wilmington in Partial Fulfillment of the Requirement for the Degree of Masters of Science
Language: English
Date: 2009
Microorganisms, Phosphorus

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