title: Characterization of phosphorus species in biosolids and manures using XANES spectroscopy.
abstract: Identification of the chemical P species in biosolids or manures will improve our understanding of the long-term potential for P loss when these materials are land applied. The objectives of this study were to determine the P species in dairy manures, poultry litters, and biosolids using X-ray absorption near-edge structure (XANES) spectroscopy and to determine if chemical fractionation techniques can provide useful information when interpreted based on the results of more definitive P speciation studies. Our XANES fitting results indicated that the predominant forms of P in organic P sources included hydroxylapatite, PO(4) sorbed to Al hydroxides, and phytic acid in lime-stabilized biosolids and manures; hydroxylapatite, PO(4) sorbed on ferrihydrite, and phytic acid in lime- and Fe-treated biosolids; and PO(4) sorbed on ferrihydrite, hydroxylapatite, beta-tricalcium phosphate (beta-TCP), and often PO(4) sorbed to Al hydroxides in Fe-treated and digested biosolids. Strong relationships existed between the proportions of XANES PO(4) sorbed to Al hydroxides and NH(4)Cl- + NH(4)F-extractable P, XANES PO(4) sorbed to ferrihydrite + phytic acid and NaOH-extractable P, and XANES hydroxylapatite + beta-TCP and dithionite-citrate-bicarbonate (DCB)- + H(2)SO(4)-extractable P (r(2) = 0.67 [P = 0.01], 0.78 [P = 0.01], and 0.89 [P = 0.001], respectively). Our XANES fitting results can be used to make predictions about long-term solubility of P when biosolids and manures are land applied. Fractionation techniques indicate that there are differences in the forms of P in these materials but should be interpreted based on P speciation data obtained using more advanced analytical tools.
authors.affiliation: Department of Soil and Water Science, Gulf Coast Research and Education Center, University of Florida, Wimauma, FL 33594, USA. alshober@ufl.edu
authors.forename: Amy L
authors.initials: AL
authors.lastname: Shober
authors.forename: Dean L
authors.initials: DL
authors.lastname: Hesterberg
authors.forename: J Thomas
authors.initials: JT
authors.lastname: Sims
authors.forename: Sheila
authors.initials: S
authors.lastname: Gardner
mesh_terms: D000042:Absorption; D000643:Ammonium Chloride / Q000737:chemistry; D064751:Ammonium Compounds; D000818:Animals; D001639:Bicarbonates / Q000737:chemistry; D017610:Calcium Compounds / Q000737:chemistry; D002951:Citrates / Q000737:chemistry; D019411:Clinical Laboratory Techniques; D017886:Durapatite / Q000737:chemistry; D005290:Ferric Compounds / Q000737:chemistry; D005459:Fluorides / Q000737:chemistry; D006878:Hydroxides / Q000737:chemistry; D008372:Manure / Q000032:analysis*; D010087:Oxides / Q000737:chemistry; D010710:Phosphates / Q000032:analysis / Q000737:chemistry; D010758:Phosphorus / Q000032:analysis* / Q000737:chemistry*; D010833:Phytic Acid / Q000737:chemistry; D000644:Quaternary Ammonium Compounds / Q000737:chemistry; D012989:Soil Pollutants / Q000032:analysis*; D013052:Spectrometry, X-Ray Emission; D013464:Sulfuric Acids / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D064751:Ammonium Compounds; D001639:Bicarbonates; D017610:Calcium Compounds; D002951:Citrates; D005290:Ferric Compounds; D006878:Hydroxides; D008372:Manure; D010087:Oxides; D010710:Phosphates; D000644:Quaternary Ammonium Compounds; D012989:Soil Pollutants; D013464:Sulfuric Acids; D014874:Water Pollutants, Chemical; D000643:Ammonium Chloride; D010758:Phosphorus; C024822:ammonium fluoride; D010833:Phytic Acid; D017886:Durapatite; C016538:lime; D005459:Fluorides