Representación espacial de la oferta y la demanda de los servicios ecosistémicos vinculados al agua

Abstract

Many of the contributions of nature to people are embodied or mediated by water. This article explores and exemplifies the spatial representation of the supply and demand of ecosystem services related to water and its application to the different needs of environmental management and policy, with particular focus in the Argentine case. The supply of these services can be mapped by combining different sources of geographic and satellite information supported by pre-established protocols or models. Their demand, even for highly subjective services such as the cultural ones, can be mapped using public photo databases or social networks. Representing supplydemand links often requires spatial abstractions or distortions. One possibility is to discretize the territory into sections and generate an exchange matrix for multiple services among them. Another one is the continuous quantification of the production and consumption of services along watersheds. Representations of ‘virtual water’ transport associated with the exchange of products can be related to the flow of water-related ecosystem services only if the water sources involved are distinguished (e.g., rain or ‘green water’ vs. irrigation or ‘blue water’ for agricultural products) and valued according to the context of the origin and destination. Each spatial representation is better adapted to different environmental management situations. Maps are valuable for land use planning. Exchange matrices are suggested to explore conflicts and cooperation opportunities. Continuous representations of watersheds are useful for evaluating hydraulic or green interventions. Finally, the analyses of virtual water exchange between countries constitute a valuable element for international negotiations. The representation of water-related ecosystem services is a pillar of nature governance, ideally co-constructed by scientists and decision makers.