désert (3) History (3) Savannas (3) Plants (3) Human beings (3) désert (3) puits (2) végétation (2) temps (durée) (2) sol (2) spectacle (2) histoire (2) matière organique (2) continent (2) Commerce (2) Weathering (2) Time (2) Stability (2) Soils (2) Sahara (2) Population (2) Organization (2) History (2) Fire (2) Desert soils (2) Culture (2) Colloids (2) Climatology (2) Climate (2) Black (2)