The fate of nitrogen forms of nitrogen fertilizers under alternate leaching and drying conditions

A soil column leaching experiment was conducted in two texture of calcareous soils to evaluate the fate of nitrogen froms of coated urea, urea and ammonium nitrate The results showed that recovery of total N (included total N in the leacheate, fertilizer N adsorbed by soil and residual fertilizer N) accounted for 90.5%, 74.2% and 93.5% of total N applied in gravel calcareous soil(the ratio of soil and gravel was 1:1.2) and 91.5%, 58.5% and 91.1% of total N applied in clay loam calcareous soil with coated urea, urea and ammonium nitrate, respectively; and cumulative NO3--N in 1750 mL of leacheate was more than 90% of total leacheate N Soil N ( NH4+-N and NO3--N) was not more than 2.1% of total N applied to the soils with different fertilizers after completion of 7 times alternate leaching and drying Nutrient released of coated urea was significantly longer than urea and ammonium nitrate, due to 62.7% and 70.8% of coated urea nitrogen presented in the soils as granular fertilizers Among three kinds of chemical nitrogen fertilizer, the ammonia volatilization loss of urea was possible higher and leaching loss of ammonium nitrate was faster in the soils