Les amendements organiques forestiers sont préférables pour la mitigation des émissions de N2O tout en conservant les sol organiques cultivés contre l'érosion éolienne
Citation
Ross-Blevis L., Pelster D., Masse J., Whalen J.K. 2023. Les amendements organiques forestiers sont préférables pour la mitigation des émissions de N2O tout en conservant les sol organiques cultivés contre l'érosion éolienne. Présentation orale dans le cadre de la conférence annuelle de la CSSS, Truro, Canada, 26 au 29 juin 2023
Résumé en langage clair
Application of organic mulch can mitigate erosion of arable organic soils. However, mulch application may stimulate microbial activity and denitrification, the dominant source of nitrous oxide (N2O) emited from arable organic soils. This study compared N2O emissions following application of mulches to arable organic soils under letuce production in Sainte-Clotilde, Québec. The experiment was designed with mulch (switchgrass, miscanthus, ash, larch, willow), fall-seeded rye, no-till, and bare fallow. During two field seasons (May-October 2021 and 2022), we assessed N2O, CO2, and CH4 flux, soil moisture and temperature, and NH4 and NO3 availability. Wood mulch produced similar cumulative N2O emissions, and grass mulch produced more N2O emissions, than the control. This was related to the higher C:N ratio of wood mulch, which affected microbial activity and denitrification.
Résumé
Application of organic mulch can mitigate erosion of arable organic soils. However, mulch application may stimulate microbial activity and denitrification, the dominant source of nitrous oxide (N2O) emited from arable organic soils. This study compared N2O emissions following application of mulches to arable organic soils under letuce production in Sainte-Clotilde, Québec. The experiment was designed with mulch (switchgrass, miscanthus, ash, larch, willow), fall-seeded rye, no-till, and bare fallow. During two field seasons (May-October 2021 and 2022), we assessed N2O, CO2, and CH4 flux, soil moisture and temperature, and NH4 and NO3 availability. Wood mulch produced similar cumulative N2O emissions, and grass mulch produced more N2O emissions, than the control. This was related to the higher C:N ratio of wood mulch, which affected microbial activity and denitrification.