Sandrine ALLAIN (UMR AGIR, INRA) : When should we spatialize indicators for ex ante assessments and why? An illustration in quantitative water management

Sustainable management of natural resources often involves a governance that is landscape-scale, participatory and future-oriented. In this context, ex ante assessments constitute useful methods to envision the consequences of different management options and to empower local actors with the capability to state their opinion about the management situation and its possible alternatives for the future. Ex ante assessments generally mobilize indicators. An indicator is a variable which value provides information on a specific issue. The information supplied by indicators is both descriptive (indicators are quantifiers or qualifier of a management option’s effects) and normative (indicators are arguments to express a value-judgment about a management option). When the resource is distributed in space (e.g. water, ordinary biodiversity, forest resources) the spatial distribution of management effects may provide a relevant information for the decision-making process, just as much as the range of these effects. Spatializing indicators has a descriptive function that is today well established; however, its normative function has not been studied yet.

We used a set of indicators built to assess scenarios of quantitative water management in an agricultural landscape (the downstream of the Aveyron watershed, South-Western France). We considered together the normative and descriptive functions of spatialization in order to clarify when to spatialize indicators, for what purpose and at which conditions.

The 154 indicators constituting our dataset were included in a database specifying their definition, meaning, estimation method, representation and normative use. For spatial indicators, we specified in addition the spatial extent and resolution at which information is estimated, at which it is represented and if it can be used to differentiate value-judgments across space. We focused on indicators for which the spatial dimensions of estimation, representation, and evaluation do not coincide – e.g. an indicator which estimated value vary in space while judgments based on this indicator should/could only be made for the entire landscape – and tried to explain why.

We found out that spatialization can be used for different purposes – gathering data, bettering knowledge about a scenario’s effect, facilitating the appropriation of information, allowing value-judgments to be differentiated across space – that are independent the one from another. We also suggest that the spatial configuration of the assessed entities, the type of issues indicators are expected to inform and the way indicators reflect real-world processes are key-elements to appreciate the descriptive and normative relevance of spatialization.