Wilhelm May

Policies that facilitate sustainability transformations require knowledge about the dynamics of complex socio-ecological systems, including biophysical mechanisms and diverse human-nature relationships. Such a comprehensive evidence base can only be built by integrating multiple types of knowledges. Ontology, epistemology, and semantics are a well-established terminology to structure and facilitate such knowledge integration. Co-creation with societal knowledge-holders can furthermore generate a more robust understanding of societal processes. Here, we present an approach that we call integrated policy assessment and use the case of Nordic forest policies to illustrate how such an integration can look in practice. We present three guiding principles to coordinate such transdisciplinary socio-ecological modelling: 1) a theory of change as a shared ontological ground about the structure of the system and causal mechanisms therein, 2) a modular architecture that integrates epistemologically distinct approaches and operationalizes data flows between various models, methods and scales, 3) a co-creative procedure that can create a shared problem understanding to semantically integrate knowledges from multiple stakeholders and address societal challenges in a relevant and legitimate way. The general idea of such co-creative modular architecture for integrated policy assessments can in principle be applied to any land use policy nexus.