Modeling of Nitrogen Losses Through Ammonia Volatilization in Second-season Corn
2019
Minato, Evandro Antonio | Besen, Marcos Renan | Cassim, Bruno Maia Abdo Rahmen | Mazzi, Fabrício Linares | Inoue, Tadeu Takeyoshi | Batista, Marcelo Augusto
Knowledge on the behavior of cumulative N-NH₃ volatilization is important for defining the strategies to reduce the N losses, as well as increasing the efficiency of nitrogen fertilization in different environments. The present study, which uses nonlinear models, aims at assessing the cumulative N-NH₃ losses through volatilization by applying different rates of urea over time to two soils cultivated with second-season corn. Two experiments were carried out; one in a clayey Oxisol, and another in a sandy-clay loam Ultisol in a randomized block experimental design. N-NH₃ volatilization was quantified by using semi-open static chambers and spectrophotometry (salicylate blue). The cumulative N-NH₃ losses were similar at both rates of urea and in both soils assessed, ranging from 34.04% to 43.15% of the N applied. The highest N-NH₃ volatilization occurred from 1.03 to 6.48 days after applying the fertilizer, and the highest volatilization rates ranged from 0.90 to 2.91 kg ha⁻¹ d⁻¹. The shortest time to reach the highest volatilization rate, associated with the highest daily rate of N-NH₃ volatilization, was seen in the Ultisol. Although the volatilizations accumulated in both soils were similar, this result was only seen due to the climatic conditions after applying the fertilizer, which contributed to minimize the N-NH₃ losses. The use of nonlinear models has shown an appropriate data adjustment, providing parameters that help to understand the behavior of N-NH₃ volatilization accumulated over time in second-season corn.
显示更多 [+] 显示较少 [-]