Soils 3,073 Soil surveys 2,993 Études pédologiques 1,164 Sols 709 Soil-surveys 133 Soil conservation 131 Maps 52 more ... Water conservation 42 Soil 38 Soil erosion 36 Conservation 35 soil surveys 30 Erosion 21 Eau 19 Land use 17 Conservation of natural resources 13 Érosion 13 Classification 11 Irrigation 10 Planning 10 Research 10 Utilisation du sol 10 Agriculture 9 Gestion 9 Land use, Rural 9 Reclamation of land 9 Soil conservation districts 9 Soil science 9 Drainage 8 Water districts 8 less ...