Chemical characterization of fresh and composted livestock manures

Effect of composting on the extractability of plant nutrients in organic wastes is essential for their recycling in sustainable soil fertility management. Therefore, an experiment was carried out to determine the concentrations of total C, total N, extractable P, K, Na and B in five types of fresh and composted manures (namely buffalo, camel, cow, goat and poultry). Laboratory results showed that the extractability of elements varied considerably with the type of composted manure. Total C varied in the order cow > goat > buffalo > poultry > camel while total N was in the order buffalo > poultry > cow > camel > goat. Total C, total N, extractable K and Na decreased with composting, whereas extractable P and B increased. Goat manure had higher pH and EC values than cow and poultry manures whether in fresh or composted samples. A marked increase in the EC value was observed in composted manures, whereas pH was reduced with composting.