Current conventional agriculture is considered unsustainable and inadequate to address great societal challenges such as climate change, environmental pollution, food security, dependence on fossil energy as well as the decline of natural resources and biodiversity. Many of these problems are related to agricultural specialization (i.e. monoculture) and the consequent simplification of the agroecosystem. In this respect, efforts aimed at improving individual agronomic techniques and at increasing the use efficiency of external inputs (e.g. synthetic inputs, fossil fuels), without modifying the structure and functions of the whole system, appear to be insufficient to achieve sustainability in most conventional and intensive farming systems. Current organic farming systems adopting the so-called input substitution approach remain intensive and highly specialized and not necessarily able to significantly improve their sustainability. This would require system diversification and redesign of the agroecosystem to increase the spatial and temporal diversification of all its components and promote positive ecological relationships between them. Agroforestry is an agricultural approach based on the diversification of the agroecosystem production components (woody perennials, such as trees or shrubs, plus crops and/or livestock) and on the intensification of the agroecological relationships between these components. As such, it has transformative potential, providing an opportunity for increasing the sustainability of organic farming. In this article, we review how the adoption of agroforestry practices could contribute to increasing sustainability in organic farming, and discuss the challenges and opportunities of this adoption.
