Knowing the soil: new challenges for managing rural land.

Soil knowledge and care have apparently lost most of their importance for french agriculture during the last decades. This was due to the agronomy and industry success in fertility management, water management and mechanisation. Nowadays changes in economic conditions and agriculture policy, environment issues and seek for sustainability are generating a reverse trend. More precise and exhaustive informations on soil properties and their spatial variations become necessary to face the new challenges for agriculture: saving costs, improving products qualities, reducing pollutions, protecting biodiversity and preventing long terme soil degradations. New tools are also required to use this more complex amount of informations in an efficient way. Modelling, data bases and GIS have to be linked in decision helping systems. For farmers technical assessment, land planning and policy decision making at different scales. Soil knowledge and data, bases must be integrated in such systems in France. Availables geographic soil data bases are for too poor to answer these needs. New programmes are developped to complete a national soil data base with a multiscale purpose and set up a soil quality observation network.