Author
 |
CODLING, ETON |
|
Submitted to: Soil Science
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 6/8/2006 Publication Date: 11/15/2006 Citation: Codling, E.E. 2006. Characterization of extractable phosphorus in poultry litter and poultry litter ash. Soil Science. 171:858-864. Interpretive Summary: One method for handling excess poultry litter (PL) is burning. Burning PL would reduce the volume of PL available for land application while generating electricity. Poultry litter ash (PLA) the by-product of burning PL. PLA contains large amount of phosphorus, calcium, potassium, magnesium and trace elements, which could be used as fertilizers for crops. Sequential extraction of PL with H2O, 0.5 M NaHCO3, 0.1 M NaOH and 1 M HCl has shown that the largest fraction of P was water-soluble, which could contribute to eutrophication of surface water. The different extractable P fractions for PLA, however, have not been determined. PL samples were collected from manure storage sheds of three poultry farms on the Maryland Eastern Shore and a portion of each PL sample was ashed at 550oc. An additional sample of PLA was obtained from a pilot study conducted by the Maryland Department of Natural Resources in which PL was burned in a wood-burning power plant. The effectiveness of four extractants in removing inorganic P (Pi) from three PL samples can be ranked from highest to lowest, as: H2O>HCl>NaHCO3>NaOH, where as PLA, the ranking was HCl>NaHCO3>NaOH=H2O. Total Pi extracted by water averaged 55% for PL and 2% for PL ashed at 550oc. Water extractable Pi from the wood burning power plant was <0.01%. Total Pi extracted by HCL fractions was 34% for PL and 82% for PLA. The low level of water soluble Pi and high level of HCl-Pi in the PLA suggest that poultry litter ash would be less of a water pollution problem with that of PL when used as fertilizer. Technical Abstract: One method for handling excess poultry litter (PL) is burning. Implementation of this practice would reduce the volume of PL available for land application while generating electricity. Poultry litter ash (PLA) the by-product of burning PL contains high concentrations of phosphorus, calcium, potassium and magnesium, which could be used as fertilizers for crops. Sequential extraction of PL has shown that the largest fraction of P was water-soluble, which could contribute to eutrophication of surface water. However, the different extractable P fractions for PLA have not been determined. PL samples were collected from manure storage sheds of three poultry farms on the Maryland Eastern shore and a portion of each PL sample was ashed at 550oc. An additional sample of PLA was obtained from a pilot study conducted by the Maryland Department of Natural Resources in which PL was burned in a wood-burning power plant. Phosphorus fractions of the PL and PLA were determined with a modified Hedley fractionation technique. The effectiveness of four extractants in removing inorganic P (Pi) from three PL samples can be ranked from highest to lowest, as: H2O>HCl>NaHCO3>NaOH, where as PLA, the ranking was HCl>NaHCO3>NaOH=H2O. Total Pi extracted by water averaged 55% for PL and 2% for PL ash at 550oc. Water extractable Pi from the wood burning power plant was <0.01%. Total Pi extracted by HCL fractions was 34% for PL and 82% for PLA. The low level of water soluble Pi and high level of HCl-Pi in the PLA suggest that poultry litter ash would be less of a water pollution problem with that of PL when used as fertilizer. |
