Amal H. Mahmoud, Maher E. Saleh and Ahmed A. El-Refaey ( 2017). Evaluation of Poultry Manure and Acidified Water for Improving Phosphorus Utilization from Bone Char: A Comparative StudyEgypt. J. Soil Sci. Vol. 57, No. 2, pp. 233 - 245 (2017)
Abstract: bone char (BC) is, recently, evaluated as one of potentially sustainable sources of phosphate fertilizer to face the accelerated depletion of mined phosphate rock (PR). Further explorations are needed to investigate its behavior when applied to soils in comparison with direct application of PR. Column leaching and greenhouse experiments were carried out to evaluate and compare the behavior of both BC and PR. Results of column leaching experiments showed that water soluble phosphorus (WSP) released from BC-filled columns represented 5 to 476 folds of that released from PR columns throughout the experiment period. Mixing poultry manure (PL) with BC or PR enhanced rate of columns leaching of WSP particularly with increasing the rate of application. Leaching by acidified water significantly increased the solubility of BC-P and PR-P compared with those released in water leachates. Similar increases were only obtained in PL:BC mixtures whereas the increases in acidified WSP were observed only in PR columns and did not occurred in PL:PR mixtures. Besides the occurrence of organic fractions of P in BC, poultry litter degradation derivatives are, probably, serve as potential complexing legends with calcium and cause a further release of P from BC in water leachate. While the huge amounts of protons (H+) in acidified water play a crucial role in apatite dissolution in both sources (BC and PR). Results of P availability after leaching showed that Olsen-P was greatly higher in all columns of BC than PR. In BC columns, concentrations of formic acid-P and citric acid-P resulted from water leached columns were higher than those resulted from acidified water leached ones while; there was no significant changes in PR columns. The higher solubility and availability of BC-P than PR-P were translated in higher biomass and grain yield of maize treated by BC-P in comparison with those treated with PR-P and their mixtures with PL.
Keywords: (Animal waste, Sustainable phosphate source, Poultry litter, Phosphate rock, P availability.)
