The cost of culture [role of natural resources in maintaining Xhosa customs in the Eastern Cape]

afrique du sud biodiversidad biodiversity biodiversité comportement culturel conducta cultural conservación de la naturaleza conservation de la nature cultural behaviour degradación degradation drug plants dégradation natural resources nature conservation pauvreté plantas medicinales plante médicinale pobreza poverty recursos naturales ressource naturelle rural areas south africa sudáfrica zonas rurales zone rurale