Location: Poultry Production and Product Safety Research
Title: Long-term effects of alum-treated litter, untreated litter and NH4NO3 application on phosphorus speciation, distribution and reactivity in soils using K-edge XANES and chemical fractionationAuthor
ABDALA, DALTON - Laboratorio Nacional De Luz Sincrotron | |
Moore, Philip | |
RODRIGUES, MARCOS - Universidade De Sao Paulo | |
HERRERA, WILFRAND - Universidad De Sao Paulo | |
PAVINATO, PAULO - Universidad De Sao Paulo |
Submitted to: Journal of Environmental Management
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 2/1/2018 Publication Date: 2/28/2018 Citation: Abdala, D.B., Moore Jr, P.A., Rodrigues, M., Herrera, W., Pavinato, P.S. 2018. Long-term effects of alum-treated litter, untreated litter and NH4NO3 application on phosphorus speciation, distribution and reactivity in soils using K-edge XANES and chemical fractionation. Journal of Environmental Management. 213:201-216. Interpretive Summary: Although soil test data can provide some information on the fertility of soils, microscopic information can provide unique insights into the chemical processes occurring in soils. The objective of this study was to determine the long-term effects of normal poultry litter, alum-treated litter or ammonium nitrate (NH4NO3) on phosphorus (P) solubility and chemistry in soils. This study utililized soil test data, sequential chemical fractionation (SCF) of P, and P K-edge XANES and µ-fluorescence spectroscopies to evaluate soil samples from a 20 year study conducted in Fayetteville, AR. Soil water extractable P data demonstrated that application of alum to poultry litter was a very effective treatment for reducing P solubility. The data from the P fractionation showed that most of the P was in the sodium hydroxide extractable fraction, regardless of the fertilizer source. Phosphorus XANES indicated that P in soil was predominantly associated with Fe>Al>Ca>organic molecules, regardless of the treatment or applied rates, though the formation of Porg-Al complexes was only found in soils that received application of alum-treated litter and was positively related to the applied rates. The combination of P-XANES with P fractionation or u-fluorescence data was shown to provide valuable information about P reactivity and distribution in soils. Technical Abstract: Whereas soil test information on the fertility and chemistry of soils has been important to elaborate safe and sound agricultural practices, microscopic information can give a whole extra dimension to understand the chemical processes occurring in soils. The objective of this study was to evaluate the effects that the consecutive application of normal poultry litter, alum-treated litter or ammonium nitrate (NH4NO3) had on P solubility in soils over 20 years. For this, we used soil test data, sequential chemical fractionation (SCF) of P, and P K-edge XANES and µ-fluorescence spectroscopies. Water extractable P data indicated that application of alum to poultry litter was a very effective treatment for reducing P solubility. On the basis of our SCF of P data, P was primarily found within the 0.1 M NaOH pool across the applied rates and regardless of the treatment, where application of alum-treated litter accounted for as much as 59 ±2% of the total, followed by NH4NO3, 49 ±4%, and normal litter, 40 ±2%. It was also shown that in soils where alum-treated litter was applied, the Resin pool accounted for 10 ±1% of the total, followed by NH4NO3, 13 ±4%, and normal litter, 18 ±2%, indicating that P was less readily available in soils where alum-treated litter was applied. Phosphorus XANES indicated that phosphate was predominantly associated to Fe>Al>Ca>organic molecules, regardless of the treatment or applied rates, though the formation of Porg-Al complexes was only found in soils that received application of alum-treated litter and was positively related to the applied rates. The combination of P-XANES with SCF or µ-fluorescence data was shown to provide valuable information about P reactivity and distribution in soils and should thus be used to address the fate of applied P amendments in soils. |