Resource management in drylands. Results of the Pre-Congress Symposium at Stuttgart 23-25 Aug, 1984 on occasion of the 25th International Geographical Congress 1984

abastecimiento de agua approvisionnement en eau arena development projects environmental factors erosion facteur du milieu factores ambientales land resources land use natural resources proyectos de desarrollo reclamation recursos de la tierra recursos naturales ressource en eau ressource naturelle sable sand utilisation des terres water resources water supply