- - - - - - download - - - - - -
Studies about sustainable development imply to jointly consider, at the time horizon of a generation, systems with processes of diverse kinds, relevant to diverse scientific disciplines, at diverse scales (from the small ecosystem to the whole planet). A common way to perform a necessary integration is the coupling of models that have already been formulated and implemented in the different disciplines. In some cases, the intrinsic complexity of the models to couple, some theoretical incoherencies between them, or the number of parameters to jointly estimate make it a difficult way. Here I propose an alternative way, less ambitious. Having looked for common features in ecological and economic processes that are involved in the exploitation of marine ecosystems, I suggest a common model to represent them and I analyze its effective implementation in several case studies. The approach f propose is based on a focus on equilibration processes in ecological and economic processes, on their interplay, the identification of possible synergies, the formalism of networks and therefore the emphasis on structural constraints, rather than on deterministic relationships, and the use of several tools from the modern mathematical theory of optimization, mainly the variational inequality and complementarity problems.