The introduction of legume-based crop rotations: an impact assessment on cereal cropping farms in Finland

Grain legume production offers multiple environmental benefits and can enhance the sustainability of farming, but the legume area has been small and declining over the last decades in most European countries. Recently, grain legumes have gained importance because of the increases in prices of feed and food proteins, fertilizers and fuel, in addition to sustainability concerns. This study investigated the impacts of introducing grain legumes [faba beans (Vicia faba L.)] in cereal-dominated crop production systems typical for southwestern Finland. To investigate the economic effects as well as the effect grain legumes have on production and land use a dynamic optimization model was used. The results suggest significant crop yield gains if farmers consistently utilize the pre-crop value of legumes and other crops in crop rotations over several years. The farm economic gains of diversified legume rotations were found to be positive but relatively small assuming past prices, but they can be significantly higher if legume and nitrogen fertilizer prices increase in the future. Overall, faba bean-based rotations have positive long-term implications on soil quality and biodiversity and thus future viability and societal reputation of farming.