Comparison of Nitrogen Loss Weight in Ammonia Volatilization, Runoff, and Leaching Between Common and Slow-Release Fertilizer in Paddy Field

摘要

Nitrogen (N) loss from paddy fields contributes to air and water pollution, which has been a serious challenge to agriculture and the environment. In situ field experiments were conducted to monitor ammonia (NH3) volatilization, surface runoff, and leaching loss in common nitrogen fertilizer and slow-release nitrogen fertilizer treatments. The total N loss by ammonia volatilization, leaching, and runoff was 38.27 +/- 4.23 similar to 113.54 +/- 7.66 kg ha(-1) among the different treatments. Results indicated that slow-coated urea could reduce ammonia volatilization (24.69 similar to 29.54%), N surface runoff loss (20.05 similar to 25.37%), and leaching loss (21.86 similar to 38.05%) compared with common fertilizer. Of the different nitrogen loss pathways monitored in paddy fields, ammonia volatilization was the greatest (68.98 similar to 75.27% of the total N loss), followed by (in descending order) runoff (16.43 similar to 23.07%) and leaching (7.67 similar to 8.86%). Ammonia volatilization and N runoff loss were predominantly attributed to surface ammonium nitrogen (NH4+-N) concentration and precipitation. In addition, 42 +/- 2.48% of N runoff loss was a result of wet deposition, while 58 +/- 3.11% was attributed to nitrogen hydrolysis. There is obvious vertical nitrogen migration in the soil profile, among which NO3--N leaching loss is the predominant form (69.94 similar to 90.12%).