Section: Application Domains

Environmental decision making

Keywords: environment, decision methods

The need for decision support systems in the environmental domain is now well-recognized. It is especially true in the domain of water quality. The challenge is to preserve the water quality from pollutants as nitrates and herbicides, when these pollutants are massively used by farmers to weed their agricultural plots and improve the quality and increase the quantity of their crops. The difficulty is then to find solutions which satisfy contradictory interests and to get a better knowledge on pollutant transfer.

In this context, we are cooperating with INRA (Institut National de Recherche Agronomique) and developing decision support systems to help regional managers in preserving the river water quality. This work began in ANR projects like APPEAU and ACASSYA or the PSDR GO CLIMASTER project (Changement climatique, systèmes agricoles, ressources naturelles et développement territorial).

The approach we advocate is to rely on a qualitative modeling, in order to model biophysical processes in an explicative and understandable way. The SACADEAU model associates a qualitative biophysical model, able to simulate the biophysical process, and a management model, able to simulate farmers’ decisions. One of our main contributions is the use of qualitative spatial modeling, based on runoff trees, to simulate the pollutant transfer through agricultural catchments.

The second issue is the use of learning/data mining techniques to discover, from model simulation results, the discriminant variables and automatically acquire rules relating these variables. One of the main challenges is that we face spatiotemporal data. The learned rules are then analyzed automatically in order to recommend actions to improve a current "unsatisfactory" situation.

Our main partners are the SAS INRA research group, located in Rennes and the BIA INRA and AGIR INRA research groups in Toulouse.

Ecosystem Management

The objective of ecosystem management is to ensure sustainable ecosystems even when submitted to various stressors such as natural disturbances or human pressures. Several studies have already demonstrated the interest of qualitative modelling for ecosystems [56] . In our case, we propose to couple a qualitative modelling with model-checking tools to explore marine ecosystems (as explained section 3.2). We applied our approach on a small-scale subsistence fishery in a coral reef lagoon (Uvea, New Caledonia). A well described foodweb model provides us with useful input data for steady-state biomass data and estimates of production and consumption. A timed automata model was developed using EcoMata to investigate the direct and indirect effects of various fishing strategies on a subset of the trophic network.

This work has been realized in collaboration with ecologists: Yves-Marie Bozec (today in position in Marine Spatial Ecology, University of Queensland, Australia) and Guy Fontenelle (Professeur at Agrocampus Ouest).

A second application has been studied in the dairy management area. Over an hydrid modelling on the grazing activities, four methods to generate the best grazing management activity has been proposed. The expert partners are researchers from the SAS INRA research group, located in Rennes.