Grazing and forest economy

arid zones bosques ciencias forestales conduite des herbages densidad density economia economics economie especies forest grazing forest resources forest stands foresterie forestry forests ganado grassland management grasslands grazing herbage livestock manejo de praderas mechanical damage methode methods migration nomadism nomadisme nomadismo pastizales pastoreo pastoreo en el bosque pastures peuplement forestier praderas recursos forestales rodales silvicultural systems sistemas silviculturales species state intervention temperate zones tropical zones zona templada zona tropical zone aride zone tropicale