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

• Published in: Biology and fertility of soils Vol. 44; no. 4; pp. 581 - 588
• Main Authors: Ciampitti, Ignacio A., Ciarlo, Esteban A., Conti, Marta E.
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer-Verlag 01.03.2008; Springer Nature B.V
• Subjects: Agriculture; Biomedical and Life Sciences; Bradyrhizobium japonicum; Crops; Decomposition; Emissions; Glycine max; Growing season; Life Sciences; Nitric oxide; Nitrous oxide; Original Paper; Soil moisture; Soil Science & Conservation; Soils; Soybeans; Studies; Denitrification; Greenhouse effect; Nitrogen; Nitrification
• ISSN: 0178-2762; 1432-0789
• DOI: 10.1007/s00374-007-0241-7

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 N 2 O emissions from the soil. Gas emissions were evaluated at field conditions by the static-chamber method. Nitrogen fertilization increased N 2 O emissions significantly ( P  < 0.05). The variable that best explained cumulative N 2 O 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 N 2 O 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 N 2 O emissions during the residue decomposition period. The relationship between soil variables and N 2 O emissions depended on crop phenological or stubbles decomposition stages.