EFFECT OF AGRICULTURAL SULFUR AND POULTRY MANURE ON AMMONIA VOLATILIZATION FROM UREA FERTILIZER IN TWO DIFFERENT SOIL TEXTURES

A pot experiment was conducted under plastic house conditions to study the effect of agricultural sulfur (2 tons ha(-1)) and poultry waste (1%) on the volatilization of ammonia from urea fertilizer that was added to the soil at the level of 160 kg nitrogen ha(-1). The experiment was carried out using two soils of different textures (clay loam and sandy loam) from the city of Mosul. The amount of volatile ammonia from the soil surface and the volatilization velocity were measured at four periods, 5, 10, 15 and 30 days from the date of adding the urea. The results showed that the degradation of urea fertilizer through the volatilization of ammonia appeared in the two studied soils, where the highest amount of volatilization was in the sandy loam soil. It was also found that the first stage that followed the addition of fertilizer gave the highest deterioration of the fertilizer, after that a gradual decrease was recorded in the amount and speed of volatilization. The results also indicated that the addition of agricultural sulfur and poultry waste led to a significant decrease in the speed and accumulated amount of volatile ammonia from urea fertilizer in all measurement periods.