Integrated hydrogeological study of surface and ground water resources in the southeastern Buenos Aires province, Argentina

ABSTRACT

This paper gives an account of the implementation of geomorphological, hydrogeological, hydrochemical and isotopic techniques to understand groundwater-surface water interactions in a multiple use area, Los Padres-La Brava Corridor [SE of Buenos Aires Province, Argentina]. The isophreatic map reveals a regional flow from the SW to NE sector, and allowed us to define the effluent-influent behavior of the permanent wetlands in the area. Hydrochemistry and isotopic analysis confirm this flow system in the unconfined aquifer and the relationships among the different water sources. Obtained data indicate that the recharge to the aquifer is influenced by the natural rainfall input, wetland discharge and the concentration of surface run-off from the range fringes to inter-range depressions. Wetlands in the corridor are considered recharge areas for the aquifer system. Moreover, they contribute to water quality as well as groundwater and stream availability. This study proposes a holistic approach to water resources management recognizing most of the components of the hydrological cycle and its interactions with other natural resources and ecosystems, both aquatic and terrestrial ones. In this sense, the idea of water resources assessment in an integrated way for an efficient management, including wetlands, streams and groundwater, is reinforced in this work