Socio-Ecological Systems and Biodiversity Outcomes

Abstract

Socio-ecological systems (SES) -- coupled human-nature systems in which social processes and ecological dynamics interact as a single integrated system -- represent the dominant framing for understanding and managing biodiversity in the Anthropocene, where the separation of 'human' and 'natural' systems is conceptually inadequate and practically misleading. The SES framework, pioneered by Elinor Ostrom's work on common-pool resource governance, has expanded from its origins in fisheries and forestry into a broad analytical framework applied to protected area management, traditional ecological knowledge, payment for ecosystem services, community-based conservation, and indigenous land management. Yet the empirical evidence base linking specific SES characteristics -- governance structure; stakeholder participation; equity; tenure security -- to measurable biodiversity outcomes remains fragmented across case studies without systematic synthesis. This study synthesises 247 SES-biodiversity outcome assessments from 84 countries, applying Ostrom's SES framework and multi-level governance analysis to identify the social, institutional, and governance conditions most strongly predicting biodiversity outcomes in managed landscapes. Community-based governance with secure tenure was the strongest predictor of positive biodiversity outcomes (partial R2 = 0.47; p < 0.001), outperforming state-managed protected areas (R2 = 0.28) and outright privatisation (R2 = 0.12) in areas where communities had long-term resource use rights. Equity in benefit sharing was the second strongest predictor (R2 = 0.38; p < 0.001), confirming that conservation initiatives that exclude local communities from resource benefits systematically underperform those that share economic benefits equitably.