Evaluating the Potential of Legumes to Mitigate N₂O Emissions From Permanent Grassland Using Process‐Based Models

Summary

Abstract A potential strategy for mitigating nitrous oxide (N 2 O) emissions from permanent grasslands is the partial substitution of fertilizer nitrogen (N fert ) with symbiotically fixed nitrogen (N symb ) from legumes. The input of N symb reduces the energy costs of producing fertilizer and provides a supply of nitrogen (N) for plants that is more synchronous to plant demand than occasional fertilizer applications. Legumes have been promoted as a potential N 2 O mitigation strategy for grasslands, but evidence to support their efficacy is limited, partly due to the difficulty in conducting experiments across the large range of potential combinations of legume proportions and fertilizer N inputs. These experimental constraints can be overcome by biogeochemical models that can vary legume