Pampean Wetlands

Abstract

The Pampean wetlands encompasses three geological-geomorphological environments: tectonic depressions, fluvial paleobelts, and deflation corridors/ hollows. Shallow lakes, overflow fans, floodplains, deltaic forms, and dunes, often coexist within these wetlands, exhibiting a close relationship between surface and groundwater systems. In this chapter, we analyse wetlands in the south of Córdoba province where two large hydrological environments have been identified: (1) Mountainous, Piedmont, and Middle Fluvial-Aeolian Plains, which are the main hydrological recharge areas and flow circulation; and (2) Eastern-Southeastern Depressed Areas, which receive water and sediments from the higher lands. The main wetlands, occupy major tectonic depressions and present a variable range of water salinity (~ 0.8–19.0 g/L). Small wetlands range from subsaline to saline (~ 0.02–5.0 g/L) and are associated with fault zones in piedmonts/middle plains, paleochannels, and deflation hollows. Since the beginning of the twentieth century, human activities such as land use changes, deforestation, dams building, and channelization have affected the wetlands. The analysis of three important wetlands, Bañados del Saladillo, Bañados del Tigre Muerto and Bañados de La Amarga, shows that their function as a discharge and storage area for water and sediments has been partially or entirely transformed into a transit area for hydrologic excesses.