Assessing the Complexity of Social-Ecological Systems: Taking Stock of the Cross-Scale Dependence

Human demands and activities introduce cross-scale pressures in different systems and scales, affecting the provision of ecosystem services and causing an unbalanced effect on human well-being within the territory. The existing institutions are frequently considered panaceas since they do not take into account the different spatial and jurisdictional scales of the social-ecological systems (SES). This paper aims to broaden the existing DPSIR (Drivers–Pressures–State–Impact–Response) assessment frameworks to strengthen the ecosystem approach and promote an integrated cross-scale perspective. The concept of the Cross-scale Ecosystem-Based Assessment (DIET) was developed and applied to a case study on the demand of seafood provisions. The assessment has indicated that the activities related to the specified demand occur at different scales and generate cumulative impacts and pressures on other scales, especially in the coastal zone. The existing responses to address this issue are highly fragmented, both spatially and among sectors. DIET was applied here to the land–sea interface to illustrate how coastal zone governance and management can be improved and how the impact of certain drivers or activities in the SES can be reduced. DIET may help to reduce the governance morbidity and prevent panaceas by fostering the integration of institutions in pursuing flexible, adaptive and fit-for-purpose policies to address complex issues so as to secure social-ecological justice and well-being for all humans.