Understanding complexity in nature-based and human-dominated river delta ecosystems

Over the past centuries, human influence over nature has risen to the level that we are now considered to live in the Anthropocene. River deltas globally epitomize this increased influence, as places where abundant availability of freshwater and fertile soils has attracted high socio-economic activity and where humans gradually moved to shape the land to their needs. The human quest for control and the relatively stable environment nurtured a paradigm of steady-state thinking. Yet, with human-induced climate change and the severe impacts of that on low-lying, densely populated coastal areas, the steady-state paradigm is being rapidly replaced with a paradigm that sees social-ecological systems as dynamic, and that humans need to adapt. While approaches such as adaptive management and nature-based solutions offer partial solutions to do so, there are deeper questions regarding complexity that need to be addressed. This thesis therefore explores how complex adaptive systems thinking, within adaptive management and nature-based solutions approaches, can be used to improve the adaptive capacity of river delta ecosystems. Using mixed-methods approaches and case studies in the Rhine-Meuse Delta of the Netherlands and the Mekong Delta in Viet Nam, it investigates how local actors use elements of complexity within the realm of freshwater management, and how their interpretations of complexity can be used to inform an integrated, broad approach to understanding complexity. The study finds that interpretation of complexity-related aspects is highly case-specific, but that localized, spatiotemporal analyses of complexity can help in advancing the understanding of complex behaviour. Case studies can help in advancing application and assessment frameworks that are better informed by experience on the ground and the availability of data. An integrated approach across five identified dimensions of dealing with complexity can help in improving adaptive capacity of delta ecosystems in transition.