Work

Contribution of denitrification and ammonia oxidation to nitrous oxide emissions from three organic soilless substrates

Year: 2025

Type: article

Abstract: Nitrous oxide (N 2 O) emissions from soilless growing substrates are significantly greater per production area than crops grown in mineral soil. To understand and identify the N 2 O production pathways in soilless substrates, fir bark, peat, and peat:fir bark substrates were treated with labeled 15 N fertilizers. The volumetric water content (VWC) of the soilless substrate was maintained near container capacity, and gas samples were collected every other day for 21 days and analyzed for 15 N-N 2 O content. Fir bark and peat:fir bark substrates had significantly greater total N 2 O emissions than peat substrate when fertilized with NH 4 NO 3 . Denitrification was the main pathway of N 2 O emissions from all substrates and it was more pronounced in the fir bark and peat:fir bark substrates. In the peat substrate, the contribution of ammonia oxidation to N 2 O emissions started on day 11 and continued to increase until the end of the experiment, contributing to 6 % of the total N 2 O emitted from this substrate. Overall, reducing denitrification-derived emissions from soilless substrates is critical to mitigate the impact of container-plant production on global warming. Future research should focus on developing strategies to reduce these emissions.

Source: The Science of The Total Environment

DOI: 10.1016/j.scitotenv.2025.179899

Authors: Bruno J.L. Pitton, Lorence R. Oki, Richard Y. Evans, Xia Zhu-Barker

Institutions: University of California, Davis, University of Wisconsin–Madison

Language: English

Topic: Soil Carbon and Nitrogen Dynamics

Subfield: Soil Science

Field: Agricultural and Biological Sciences

Domain: Life Sciences

SDGs: Climate action, Responsible consumption and production

Open Access status: hybrid

Estimated APC paid: $4,250