Abstract for: Addicted to Fertilizers - How soil mismanagement makes our food systems increasingly vulnerable

A System Dynamics model of the bio-physical dynamics involving soil organic matter and mineral nitrogen is used to analyse the implications of different farming practices, in particular in terms of mineral fertilizer use, on the sustainability of the farming system and land fertility. The analysis reveals how industrial agriculture practices in search of higher yield can backfire as the soil becomes ‘addicted’ to fertilizer, soil organic matter is degraded, and natural soil fertility is undermined. Our results indicate that an agricultural system that is highly dependent on synthetic fertilization, is not only unsustainable, but also vulnerable to the risk of a likely future scarcity in external inputs (e.g. as a result of rising energy prices). In the event of such fertilizer scarcity shock, a consequent transition from industrial to sustainable agriculture practices is going to be a lengthy and expensive process. Our analysis indicates that the sooner the transition happens, the quicker and the less costly it is going to be.