Effect of Drying on Phosphorus Distribution in Poultry Manure

Trade or manufacturers' names mentioned in the article are for information only and do not constitute endorsement, recommendation, or exclusion by the USDA‐ARS.

Abstract

Laboratory drying may alter manure phosphorus (P) distribution. The effects of freeze, air (22°C), and oven (65°C) drying on sequentially fractioned poultry manure P were examined. Higher drying temperatures resulted in lower percentage of dry matter. Increased H₂O‐ and decreased sodium bicarbonate (NaHCO₃)‐extractable P with drying provided evidence that drying increases poultry manure P solubility. Labile fractions were predominantly inorganic P (P_i), whereas sodium hydroxide (NaOH) and hydrochloric acid (HCl) fractions had significant amounts of organic P (P_o). Drying altered H₂O‐ and NaHCO₃‐extractable P_i but had no consistent effect on P_o in these fractions. This work suggests that variations due to drying should be taken into consideration when evaluating manures for P availability or when comparing data in which different drying methods have been utilized.

Keywords:

• Inorganic phosphorus
• manure drying
• organic phosphorus
• phosphorus
• poultry manure
• sequential phosphorus fractionation
• total phosphorus

Notes

Trade or manufacturers' names mentioned in the article are for information only and do not constitute endorsement, recommendation, or exclusion by the USDA‐ARS.