Phosphorus Desorption from Fe and Al Oxides Mediated by Soil Microorganisms

• Published in: Communications in Soil Science and Plant Analysis Vol. 46; no. 5; pp. 633 - 640
• Main Authors: De Araújo, Lílian Maria César, Sampaio, Everardo Valadares De Sá Barretto, De Araújo, Maria Do Socorro Bezerra
• Format: Journal Article
• Language: English
• Published: Philadelphia Taylor & Francis 09-03-2015; Taylor & Francis Ltd
• Subjects: aluminum; aluminum oxide; Brazilian tropical soils; carbon; carbon dioxide; desorption; Fe and Al oxide paper strips; glucose; iron; microbial activity; phosphorus; soil; soil microorganisms
• ISSN: 1532-2416; 0010-3624; 1532-2416; 1532-4133
• DOI: 10.1080/00103624.2015.1005218

The capacity of soil microorganisms to desorb phosphorus (P) adsorbed to iron (Fe) and aluminum (Al) oxides was determined by impregnating paper strips with these oxides, adding P in quantities equivalent to the null points, and incubating the strips in Argisol and Latosol samples receiving increasing doses of glucose (0 to 10 mg g soil ⁻¹). Glucose stimulated microbial activity and at the end of the incubation period 69 and 41 percent of the added carbon (C) had been released as carbon dioxide (CO ₂) in the Argisol and Latosol. This stimulated activity resulted in increasing P desorption, reaching 66 and 67 percent of the adsorbed P in the Fe strips and 49 and 80 percent in the Al strips for the Argisol and Latosol, respectively. Therefore, microorganisms can desorb P adsorbed to Fe and Al oxides when stimulated by an easily assimilated C source. Fe- and Al-oxide-impregnated paper strips technique provided an adequate method to measure soil P desorption, as mediated by microorganisms.