The role of red clover (Trifolium pratense L.) in mitigating greenhouse gas emissions: Insights from a temperate agricultural ecosystem

Agriculture, forestry, and land use contribute approximately 22 % of global anthropogenic greenhouse gas emissions, with nitrous oxide (N₂O), methane (CH₄), and carbon dioxide (CO₂) playing pivotal roles in climate change. This underscores the urgency of adopting sustainable practices such as crop rotation and cover cropping. Red clover, a nitrogen-fixing legume, offers potential for mitigating greenhouse gas emissions by enhancing soil fertility, reducing reliance on synthetic fertilisers, and improving soil health. This study examines the seasonal and management related dynamics of greenhouse gas emissions in temperate agricultural systems and evaluates the short-term and long-term effects of red clover cultivation on soil N₂O, CO₂, and CH₄ fluxes. In addition to crop specific effects, the study identifies key environmental and agronomic factors influencing emission patterns, including soil type, tillage system, farming system, and seasonal temperature and moisture fluctuations. Notably, red clover cultivation initially increased N₂O (7.06 g ha⁻¹ d⁻¹) and CO₂ (137.23 kg ha⁻¹ d⁻¹) emissions due to biological nitrogen fixation and elevated microbial activity, followed by emission fluctuations linked to organic matter mineralisation. In contrast, CH₄ fluxes remained consistently negative, indicating a methane sink effect (-6.54 g CH₄ ha⁻¹ d⁻¹ in year three). These findings highlight the complex interplay between management practices and environmental variables in regulating soil greenhouse gas emissions and underscore the need for further research on biomass contributions to support climate resilient agriculture. • Red clover cultivation affects soil GHG emissions, with initial N₂O and CO₂ increases. • Seasonal and management factors drive fluctuations in soil GHG fluxes. • Red clover fields act as a methane sink, reducing CH₄ emissions.