Nitrous oxide emissions from soil during soybean [(Glycine max (L.) Merrill] crop phenological stages and stubbles decomposition period

• DOI: 10.1007/s00374-007-0241-7
• Publication Date: 2007-10-05T11:59:16Z
• Authors: Ignacio A. Ciampitti; Esteban A. Ciarlo; Marta E. Conti
• Keywords: NITROGEN; 2. Zero hunger; GREENHOUSE EFFECT; 13. Climate action; https://purl.org/becyt/ford/4.1; 0401 agriculture, forestry, and fisheries; https://purl.org/becyt/ford/4; DENITRIFICATION; 04 agricultural and veterinary sciences; 15. Life on land; NITRIFICATION

The purpose of this study was to evaluate, during the phenological stages of inoculated soybean crop [Glycine max (L.) Merrill], the effect of different N fertilization levels and inoculation with Bradyrhizobium japonicum on N2O emissions from the soil. Gas emissions were evaluated at field conditions by the static-chamber method. Nitrogen fertilization increased N2O emissions significantly (P < 0.05). The variable that best explained cumulative N2O emissions during the whole soybean growing season was the soil nitrate level (r 2 = 0.1899; P = 0.0231). Soil moisture presented a greater control on N2O emissions between the grain-filling period and the crop commercial maturity (r 2 = 0.5361; P < 0.0001), which coincided with a positive balance of the available soil N, as a consequence of the decrease in crop requirements and root and nodular decomposition. Only soil soluble carbon (r 2 = 0.29; P = 0.019) and moisture (r 2 = 0.24; P = 0.039) were correlated with N2O emissions during the residue decomposition period. The relationship between soil variables and N2O emissions depended on crop phenological or stubbles decomposition stages.