Integrating soil and water resources in local development framework: the ASTUCE & TIC program.

Urban growth is a factor of productivity but urban spreading is a major threat for soil and water resources. Local development must consider a city with its hinterland (Figures 1 and 2). Soil and water resources are needed for food production, water supply and their degradation can impair the possibilities of cities to generate wealth and the economic resources for financing local development and managing public resources (Figure 3). Data are generally available but dispersed. There exist already numerous models, separately calibrated and checked, that allow the users to take into account land use change and climate change to evaluate the modifications of soil properties due to urbanization, the crop requirements of water and nutrients, the geochemical interactions between soils and water and economic models based upon cost/benefits approach. The ASTUCE & TIC program aims at showing that different models of the type above can be integrated to help policy-markers to cope more efficiently with urban spreading.