Emissions of N2O following field incorporation of leguminous and non-leguminous cover crops
Year: 2024
Type: article
Abstract: Cover crop (CC) cultivation can reduce N leaching from agricultural fields. It has also recently been proposed as a measure to mitigate climate change due to its potential for increasing soil carbon (C) stocks and reducing soil nitrous oxide (N2O) emissions during CC growth. However, the input of immature, low C/N ratio plant material to the soil can increase the risk of N2O emission upon CC termination. In a field trial under humid temperate conditions, N2O emissions from two leguminous CC species – hairy vetch (Vicia villosa) and crimson clover (Trifolium incarnatum) – and from two non-leguminous CC species – oilseed radish (Raphanus sativus) and winter rye (secale cereale) – were measured in the spring from 24 days before incorporation to 54 days afterwards. The vetch had a significantly higher shoot N concentration and consequently lower C/N ratio than the other three species, but this did not increase N2O emissions relative to the fallow control. Indeed, oilseed radish was the only cover crop to significantly increase N2O emissions by 290 g N2O-N ha-1 during the measurement period relative to the fallow control. These results suggest that parameters other than the shoot C/N ratio, such as total biomass and biomass N content, may be of greater importance for predicting N2O emissions from immature cover crop residues.
Institution: University of Copenhagen
Language: English
Subfield: Soil Science
Domain: Life Sciences
Open Access status: hybrid
Estimated APC paid: $3,840
OpenAlex ID: W4403928094