Effect of poultry,cattle, sheep manures and sewage sludge on N mineralisation

The effects of various organic wastes on nitrogen mineralisation in soil were investigated. For this purpose, poultry (pl), cattle (ct), sheep (sh) manures and sewage sludge were used as organic wastes. This study was conducted as a laboratory incubation experiment with a calcareous soil. Organic wastes (3%) were added to pots of soil and incubated at 28°C for 16 weeks under non-leaching conditions. The cumulative mineralised N was then fitted to a single exponential model. Maximum nitrogen mineralisation was determined in the second week of incubation in soil treated with poultry manure. Overall, the results showed that the amount of mineral nitrogen in soil treated with different organic wastes was controlled by the type of manure. The results indicated that among the organic wastes, sewage sludge induced the highest quantities of net N mineralisation. Generally, organic wastes increased the amount of N mineralisation in the studied soil and the values of N₀ and k in treated soil varied depending on the type of organic waste. The highest N₀ and k values were found in poultry-treated soil.