Biodiversity evidence for integrative policy and collaborative governance: nexus mechanisms across climate, food, water, energy, transport and health

Biodiversity loss and ecosystem degradation, exacerbated by climate change, represent one of the most urgent governance challenges of our time. Effective policy responses remain constrained by fragmented understanding of how biodiversity interacts simultaneously with climate, food, water, energy, transport, and health systems. This study addresses this gap through an evidence synthesis of 194 European studies examining biodiversity interactions across terrestrial, freshwater, marine, and multi-realm contexts. An impact archetype analysis was conducted with a causality visualisation tool to classify systems interactions according to their structure and complexity, including unidirectional influences, bidirectional reinforcing or balancing feedbacks, and multidirectional cascading or compounding effects, and to assess their direction (positive, negative, mixed) across seven nexus sectors. The findings show that biodiversity functions as an active component of the nexus, both as mediums and mediators through which other sectors interact in diverse forms of feedbacks and pathways. Positive-reinforcing feedbacks linking biodiversity conservation, ecosystem health, human behaviour, and cross-sectoral co-benefits are widespread but understudied and underleveraged. ... mehrConversely, negative cascades associated with agricultural intensification, fossil fuel consumption, land-use change, and transport infrastructure propagate across sectoral and realm boundaries, generating risks that cannot be effectively anticipated or managed through single-sector governance approaches. Biodiversity governance therefore requires coherent and integrative cross-sectoral policy that deliberately amplifies positive feedbacks, interrupts harmful cascades, and embeds co-benefits and trade-off analysis into policy planning and adaptive management. Biodiversity demands to be governed not as a sectoral externality, but as a dynamic nexus component central to achieving nature- and people-positive futures.