desertification map africa risk areas shows droughts where water desert clean sahel world most land agricultural erosion deserts caused sahara
desertification vulnerability challenges mapping constraints
desertification drylands vulnerable global ecosystem desert assessment chart categories their japan millennium source
saharan desertification atlas geography libretexts natural socialsci pressbooks nscc conservation landforms
desertification climate degradation atlas drought climates threats deforestation vulnerability risks convergence third
aridity desertification arid trockengebiete humid dry klimawandel landnutzung erde drylands semiarid livestock subtypes globale