Regional Integrations in Arid Central West Argentina: Trends and Expectations from a Human Paleoecological framework

ADOLFO GIL, MERCEDES CORBAT, ATILIO ZANGRANDO, GUSTAVO NEME, CLARA OTAOLA, LAURA SALGAN, LEANDRO DAVID ROJO, VALERIA CORTEGOSO, VÍCTOR DURÁN, MARTIN SANTIAGO PALMA

Southampton

Workshop; ‘Regional integration of past records for management of modern resources and landscapes’PAGES/LWEC 4; 2010

University of Southampton

Central west Argentina is a semiarid but highly heterogeneous landscape (Figure 1). This area is located between 30° and 37° S, and can be subdivided into three environments: the western mountain area and the south western volcanic plateau of La Payunia, characterised by a mean annual precipitation ranging between 200 and 400 mm, and piedmont, depressions and oriental with a mean annual precipitation below 250 mm. The area is located over the South American Arid Diagonal and within the inversion zone of precipitation regimes. It is affected by the action of the Atlantic anticyclone (piedmont, depressions and oriental plains) and the Pacific Ocean anticyclone (western mountains and volcanic plateau). From the morpho-climatic aspects, the subregions within Cuyo are highly contrasting due to their relief, the dominant masses of maritime air and the season of dominant precipitation. Due to the great distance travelled, the humid winds of the Atlantic produce little precipitation, mainly in summer, while the winds from the Pacific bring precipitation, principally in winter, at the mountain range of the Andes and volcanic plateau. As these winds cold adiabatically and lose moisture by rain shadow effect on western area, they gain heat and arrive at eastern lowlands generally dry and warm. In phytogeographic terms, there are four types of deserts vegetation: Altoandino, Puna and Patagonia distributed along mountains and plateau where grasses and cushion plants with Adesmia spp., Mulinum spp., amongs others as dominant that characterise the physiognomy; and Monte in lowlands characterised by shrub steppes with dominance of Larrea spp. (Zygophyllaceae) and species of Prosopis in open woodlands where groundwater is available (Figure 2, 3, 4, 5). Today, the highest human density demography is localized in some “oasis” mostly in fluvial valleys. The human settlement is very heterogeneous with regular size urban centres and a high number of spread households. The economy is variable, farming and pastoral activity occupying the biggest area. However, mining and other industries are being developed today.