Leveraging agrobiodiversity for sustainable transition in greenhouse-based intensive agriculture across Mediterranean drylands

Dryland regions cover more than 40% of Earth's land, support around one-third of the global population, and are continuously expanding because of Climate Change and other drivers of Global Change. To overcome the harsh conditions for agriculture development and sustain food security, dryland regions have adopted intensive agricultural practices, notably greenhouse-based groundwater-dependent horticulture. The southern coastal plains of Almería, SE Spain, the driest region of the entire European continent, exemplifies this agricultural model by hosting the second largest concentration of greenhouses in the world. Since its origin in the 1960's, greenhouse horticulture in Almería has been considered a model of success, producing millions of fresh produce, contributing to the economic prosperity and social structuring, and adapting to the growing requirements of quality and safety. However, the once-celebrated "Almería's economic miracle" is currently facing signs of socioeconomic collapse and environmental exhaustion, driven by the depletion of natural resources, especially water, sand and soil, waste management challenges, e.g., plastic and biomass, and significant threats to (agro)biodiversity. We explore here a possible transition in Almería's agricultural model towards a more sustainable paradigm based on leveraging agrobiodiversity for crop diversification. This tentative model will be supported by agroforestry systems based on perennial woody crop species, which may offer high added value, adaptability to the changing and stressful conditions driven by Global Change, and potential for ecological restoration of degraded lands. We believe Almería is positioned as an ideal “laboratory” for proposing a new agricultural model that reconcile food security and environmental sustainability. • Mediterranean dryland regions have adopted greenhouse-based agricultural models. • We examine the sustainability challenges of the above model in Almería, SE Spain. • Agrobiodiversity and crop diversification can foster a sustainable shift of the model. • Almería is positioned as an ideal “laboratory” for testing this new agriculture model.