Nitrogen fluxes from irrigated common-bean as affected by mulching and mineral fertilization.

• Main Author: CARVALHO, M. T. de M.
• Publication Date: 2013
• Other Authors: MADARI, B. E., LEAL, W. G. de O., COSTA, A. R. da, MACHADO, P. L. O. de A., SILVEIRA, P. M. da, MOREIRA, J. A. A., HEINEMANN, A. B.
• Format: Article
• Language: eng
• Source: Repositório Institucional da EMBRAPA (Repository Open Access to Scientific Information from EMBRAPA - Alice)
• Download full: http://www.alice.cnptia.embrapa.br/alice/handle/doc/964556
• topic: Óxido nitroso; Feijão; Phaseolus vulgaris; Brachiaria; Plantio direto; Cobertura morta; Cerrado; Nitrogênio; Óxido; Efeito estufa; Fertilidade do solo; Mudança Climática

The objective of this work was to measure the fluxes of N2O-N and NH3-N throughout the growing season of irrigated common-bean (Phaseolus vulgaris), as affected by mulching and mineral fertilization. Fluxes of N2O-N and NH3-N were evaluated in areas with or without Congo signal grass mulching (Urochloa ruziziensis) or mineral fertilization. Fluxes of N were also measured in a native Cerrado area, which served as reference. Total N2O-N and NH3-N emissions were positively related to the increasing concentrations of moisture, ammonium, and nitrate in the crop system, within 0.5 m soil depth. Carbon content in the substrate and microbial biomass within 0.1 m soil depth were favoured by Congo signal grass and related to higher emissions of N2O-N, regardless of N fertilization. Emission factors (N losses from the applied mineral nitrogen) for N2O-N (0.01-0.02%) and NH3-N (0.3-0.6%) were lower than the default value recognized by the Intergovernmental Panel on Climate Change. Mulch of Congo signal grass benefits N2O-N emission regardless of N fertilization.