Examining in this way, the Caatinga that is the true essence of the desert. Where if they come across the main nuclei of dryness of the Region. Providing a vegetation in the high one of its aggressiveness and the maximum of its convergence of adjustment to the climatic severity, to the extreme dryness of the place. Thus, the Wasteland and the High Hinterland are alleviated formats of the Caatinga. To the opposite of what one expects of the biggest natural adversity of the Hinterland is not the diminished pluviomtrica precipitation (between 250 and 6000 mm annual ones), but its irregular distribution, therefore rains are concentrated in only one station of the year (of December the May), regionally winter call. This ticket conditions the simple economic life, that if desestruturam completely when so believed rain it does not occur. It dries confronts already difficult social conditions, therefore the small owners do not have environment of if preventing.
The good proprietors only finance the resources to establish barrages, wells and dams. Thus, if come across with the emigration. Taking most of the sertanejos if to disarticulate for the coast and other regions of the country, especially the Southeast. In accordance with AB? TO KNOW, on advent of the climate in the Hinterland affirms. For daily of sertanejo and the survival of its family the more serious factor interferente inhabits in the periodic climatic irregularities that devastate the social space of the dry sertes. In the truth, the sertes northeasterns do not escape to a peculiar fact to all the half-barren regions of the world: the climatic variability. Thus, the average of annual precipitations of a locality any serves only for normatizao and reference, in face of gotten climatic data in many years. (AB? TO KNOW, P. 91). However, in heaths, adjacent humid lands of abundant rivers practise it policultura, in general, with commercial objectives.