Towards farm-level net-zero greenhouse gas emissions: Contributions of climate mitigation actions – A study of four European crop and dairy farms

Achieving net-zero greenhouse gas (GHG) emissions in agriculture is a central objective of climate policy frameworks such as the Paris Agreement. This study explored the feasibility and trade-offs of achieving net zero at the farm level by combining life cycle assessment with modeling of soil organic carbon (SOC) stocks. Four case-study farms, two crop and two dairy, in Italy, the United Kingdom (UK), France, and Germany, and 11 mitigation actions were assessed under two 20-year eco-design scenarios: one maintaining >= 90% of baseline productivity (PM), and one achieving net zero. The scenarios combined nature-based solutions (e.g., organic fertilization, cover crops) with technological interventions (e.g., feed additive, solar power). Estimated GHG emissions decreased greatly, but SOC sequestration alone was insufficient to achieve net zero while maintaining productivity. Under the PM scenario, the Italian, French, and German farms still emitted 51%, 62%, and 84% of baseline emissions, respectively. The UK crop farm achieved net zero under the PM scenario, but had the highest ecotoxicity impact per ha, 11% higher than that of the Italian crop farm. Mitigation effectiveness depended on soil- and crop-management practices, baseline GHG emissions, and carbon inputs. Assumptions about the 20-year amortization window, nutrient cycling, and indirect GHG emissions influenced trade-offs between environmental impacts and productivity. Net zero may be pursued more effectively through cooperation among farms at the landscape or sector level. Assessing the entire agricultural value chain, improving model calibration, and supporting long-term transitions through policies will be essential for developing climate mitigation actions adoptable across European agriculture.