Effects of Value-added Urea on Ammonia Volatilization and Soil Urease Activity

Soil incubation under 25℃ was applied to study the ammonia volatilization and soil urease activity of normal urea and value-added urea which was manufactured by melted urea with different organic synergists.The results showed that the value-added urea F-5 and H-5 decreased the accumulation of ammonia volatilization by 15.2% and 13.3% compared to the normal urea.The peak of ammonia volatilization was deferred by the treatment F-5 and the peak value was brought down by the two treatments whose variation curves were relatively stable.The treatment F-5 and H-5 could inhibit the soil urease activity and prolong the release time of urea.Compared with normal urea,the effects of F and H value-added urea on the ammonia volatilization reduction and the soil urease activity inhibition were significant.