Leaching and Recovering of Nitrogen Following N Fertilizers Application to the Soil in a Laboratory Study

ABSTRACT

Following soil fertilization, nitrogen (N) is partially lost. The objective of this study was to evaluate leaching and recovery of N after addition of fertilizers to the soil. Two experiments were conducted in leaching columns submitted to frequent water percolations. In the leaching experiment, urea, ammonium nitrate, and six coated N fertilizers were utilized; in the N recovery experiment, treatments consisted of urea, potassium nitrate, ammonium sulfate, and ammonium nitrate, combined or not with percolation. Percolations were performed weekly with quantification of ammonium and nitrate in the percolated. The recovered N was obtained by summing total N percolated with N in the soil. Nitrate leaching was highest from amide-N fertilizers, with no differences between them showing that coating urea was not efficient to decrease N leaching. Nitric fertilizers had the lowest recovery of N, probably due to the occurrence of denitrification caused by the frequent water percolation.

KEYWORDS:

• Coated urea
• nitrogen losses
• slow release fertilizer
• water percolation