Legume tree-based farming systems sit at a crucial nexus of agroecological sustainability. Their capacity to support microbial N2 fixation can increase soil nitrogen (N) availability and therefore improve soil fertility, crop yields, and support long-term stewardship of natural resources. However, increasing N availability oftentimes catalyzes the release of N into the surrounding environment, in particular nitrous oxide (N2O) — a potent greenhouse gas. We summarize current knowledge on the agroecological footprint of legume-based agroforestry and provide a first appraisal of whether the technology represents a pathway toward sustainable development or an environmental hazard.
Rosenstock, T.S.; Tully, K.L.; Arias-Navarro, C.; Neufeldt, H.; Butterbach-Bahl, K.; Verchot, L.V. Agroforestry with N2-fixing trees: sustainable development’s friend or foe? Current Opinion in Environmental Sustainability (2014) 6: 15-21. [DOI: 10.1016/j.cosust.2013.09.001]