Ecosystem complexity described with ontological tool for a multi-scale, multi-model approaches in distributed environment

International audienceAquatic ecosystems are natural complex systems. They are the site of a great number of phenomena. Thus, many studies model each of these phenomena, using law-based approach (most of the time differential equations) or rulebased approach (individual-based models in particular). Owing to their complex nature, aquatic ecosystems are hard to study and resist a reductionist approach. We based our model on the holarchic (non directional hierarchic) nature of the ecosystems. First, aquatic ecosystems are crossed by structuring fluxes (light radiation, mass transport, etc.) which are mainly conveyed by fluid flow. So, we propose to model these fluid flows with a multi-scale simulation detecting emergent formation and managing them on different scales. Second, a part of aquatic ecosystems are species organizations called food chain. These ones are themselves interacting complex subsystems with multi non-directional retroactions between them and their environment. These retroactions can be modeled at different levels. Thus, we propose an hybrid holarchic compartmental model. This one aims at easing the gathering of phenomenon in a multi-model, multilevel simulation for studying food chain. We finally present a fluid-flow simulation and a food chain simulation using the proposed models