Résumé
This Ph.D. thesis studies crop-livestock complementarities enabled by legumes in the region of western France. Economic and environmental assessment of these complementarities is performed from the farm scale to the regional scale. The main contribution of this research is the development of the bio-economic model SYNERGY, which represents local exchanges of crops (including legumes) and manure between crop-oriented farms and livestock-oriented farms. This model represents the pre-crop effect of legumes and includes alternative rations with these high-protein crops. The main simulation results show that coupled subsidies to legumesincrease their production but do not lead to better valuation of technical complementarities. One way to increase the use of legumes in animal feed is to label GMO-free animal products. However, since the simulated local exchanges of legumes remain low, these crops are largely imported from outside the region. Thus, the economic and environmental results do not improve at the regional scale, and protein self-sufficiency decreases.Finally, at the scale of the agro-food chain, exchanges of legumes lead to high transaction costs, which current contracts reduce only slightly. Developing markets that value local resources could foster legume production.increase their production but do not lead to better valuation of technical complementarities. One way to increase the use of legumes in animal feed is to label GMO-free animal products. However, since the simulated local exchanges of legumes remain low, these crops are largely imported from
Source: http://www.theses.fr/2020NSARE054
.