EFFECT OF LIMING AND POULTRY MANURE ADDITIONS ON C, N AND P MINERALIZATION IN AN ACID ULTISOL

Abstract

A laboratory incubation study was conducted over a period of 6 weeks at 30C to evaluate the effects of liming (pH 7.0) and varying rates of poultry manure additions (0, 0.25, 0.50 and 0.75%) on microbial respiration. NO₃-N and available P production in an acid (pH 4.8) Ultisol. The results indicated that liming, with and without poultry manure additions significantly increased microbial respiration NO₃-N and available P concentrations in the soil. Liming soil amended with poultry manure also significantly increased these parameters over the corresponding unlimed treatments. Nitrate N and available P production generally peaked at the end of the 4th week of incubation. The results further showed that NO₃-N production in poultry manure - amended acid soil can be predicted from the CO₂ evolution data