Coastal systems in transition: The game of possibilities for sustainability under global climate change

To achieve ecological sustainability and sustainable development represents a crucial challenge for the human kind, which depends on numerous driving forces, frequently opposing each other. Nevertheless, when dealing for instance with estuaries and coastal areas, three major drivers may in any case be identified, which are the search for human well-being in its several aspects, the conservation of environmental equilibrium, essential to ecological sustainability, and systems' resilience in face of an increasing human pressure, resulting from population size and prosperity demand. To build and test environmental management scenarios involves therefore complex conceptual problems, demanding appropriate conceptual tools as for example the Ecological Sustainability Trigon (EST). Conceptually, the EST allows addressing the referred main drivers by using the human society view as a common currency, and to describe our behavior, energetics (economy), and dynamics based on ecological theory. Besides, the EST behaves promisingly as a gap analysis tool and a mean to address new research questions. Since its proposal, the EST has been further tested, namely in relation to the functioning and management of estuarine ecosystems and coastal areas, taking the Mondego Estuary (western Portugal) as core case study.