Abstract

Release of phosphorus (P) from terrestrial environments undermines water quality by contributing to eutrophication in lakes and rivers. Soil amendment is considered one of the best management practices to reduce P loss from sandy soils. Laboratory leaching experiments were conducted to evaluate the effectiveness of different soil amendments in reducing P leaching from a typical sandy masa soil in Japan. Burned and unburned poultry litters (PL) are commonly used as a fertilizer and amendment to improve soil productivity. Application of biosolids to meet the nitrogen requirements of crops can lead to accumulation of P in soils, which may result in P loss to water bodies. Long-term application of P with animal manure in amounts exceeding removal with crops leads to buildup of P in soil and to increasing risk of P loss to surface water and eutrophication. We investigated the mobility of P in burned and unburned PL samples from a sand dune Regosol and Masa Terrestrial Regosol (Japanese soils). Soils amended with either PL or poultry litter ash (PLA) differed greatly from those with no litter application. Poultry litter ash application to soils significantly increased the total P as compared to the soils amended with PL. Masa soil contained higher extractable P than sand dune soil. Manure amended soils differed for P release in the order of PLA masa > PLA sand > PL masa > PL sand > control. The higher P concentration in the ash resulted from elimination of the carbon during burning of the litter. The concentrations of K, Ca and Mg in leachate varied irrespective of the total amount applied with PL.

Key words: Phosphorus movement, poultry litter ash, soil fertility, metal ions leaching.