Long-term community management of agrobiodiversity zones reduces agricultural expansion and natural cover loss.

Anna Comacchio , Carolina Tovar, Sophie Jago, Sarah Jones, Natalia Estrada-Carmona, Elisabeth Fernandez Huaytalla, Cristina Quinatana Palacios, Dina Gutiérrez Reynoso, Tulio Medina Hinostroza, Michelle Koechlin Cuba, Oscar Olazábal, Ronald Catpo, Diego Sotomayor, James Borrell

Global food system resilience is weakened by over reliance on a narrow range of crops and the erosion of traditional farming knowledge. Agrobiodiversity Zones (ABDZs) in Peru represent a novel and globally unique, community-led legal instrument for in situ agrobiodiversity conservation. However, the long-term impact of community-led stewardship and associated traditional farming practices on landscape management has not been evaluated.

This study applies a counterfactual approach using high-resolution remote sensing data to characterise agricultural land use change between 2000 and 2022. We compare changes in agricultural expansion, natural cover loss, gross primary productivity (annual means and interannual variability) and mean field size between ABDZs and socio-ecologically matched control landscapes across the Peruvian Andes.

We find significantly less agricultural expansion and natural cover loss in ABDZs than in control areas, equivalent to ~3323 ha of avoided agricultural encroachment and ~3713 ha of avoided forest and grassland loss over the study period.

Field size remained stable, and gross primary productivity increased in both groups, but ABDZs showed significantly more interannual variability in gross primary productivity, suggesting divergence in agricultural management strategies.

These findings demonstrate that community-led area-based agrobiodiversity management can effectively limit agricultural land expansion and landscape simplification, providing a unique contribution to national food system and landscape management for wild and cultivated diversity conservation. The study provides a scalable, open-data-based framework for monitoring and evaluating area-based agrobiodiversity policy outcomes.