Volatilization of ammonia in stabilized slow-release nitrogen fertilizer under controlled conditions

The loss of nitrogen through volatilization leads research to the search for new technologies that release nutrients in a manner synchronized with the crop demand, minimizing losses and increasing efficiency of its use in agriculture, as is the case with the stabilized slow-release nitrogen fertilizer. This work sought to evaluate the losses of volatilized N-NH 3 in stabilized slow-release nitrogen fertilizer applied to the soil. The treatments followed a 5 3 2 factorial as follows: five nitrogen fertilizer sources (conventional urea -CU; urea combined with zeolite -UZ; sulfur coated urea -US; NBPT coated urea -U NBPT , and urea combined with organic material -OU); three application times; and two managements (surface and incorporated applications) with three replications. The experiment was conducted using a collection chamber to capture NH 3 for 25 days, with samples taken at 2, 4, 7, 9, 11, 14, 16, 18, 21, 23 and 25 days after the start of the experiment. The ascending order of N-NH 3 volatilization was: UZ < US < CU < U NBPT < OU, regardless of the time and management adopted. For all the sources used there was a loss reduction from 20.45% to 12.29%, when N sources were parceled, and from 19.63% to 13.95% when they were incorporated.