Abstract

SAMANTHA ALCARAZ, Omar Daniel; TADEU-VITORINO, A. Carlos  and  SANNIER, Christophe. Relations between hidrogeomorphic attributes of the Dourados basin-Brazil and their enviromental signficance. Agrociencia [online]. 2011, vol.45, n.3, pp.267-279. ISSN 2521-9766.

The study of the morphometry within of catchment boundaries allowed to quantify aspect of the fluvial system in relation to geology, geomorphology and hydrology of the basin of Dourados river, Brazil, making possible to analyse the relations between hydrographic and environmental properties like the first step to better understand the processes taking place within the catchment area. The drainage network was described using qualitative and dimensional observations, from which significant quantitative attributes were derived, including interpolated drainage density and drainage frequency. Environmental data such as geology, geomorphology and soils type were acquired to allow an interpretation of their relationships with the drainage network. The geomorphologic and hydrologic characteristics confirm that the drainage system is strictly dependent on the nature of the bedrock, and on its regional and local structural control. Basaltic lava flow and associated soils shape tabular landforms where dendritic network of low drainage density and low density of dissection are develop. On sandstone and residual basal conglomerate, the drainage frequency is lower but the relief variation is locally increased by erosion processes that create deep and narrow valleys. The drainage network does not appear strongly influenced by regional tectonic control. Nevertheless, lineaments on NW-SE and NE-SW trends could be related to structural constraints affecting the western area of the sedimentary Paraná basin, in relation to the Andine orogeny. To highlight the influence of soil distribution on the drainage network, a smaller area of interest would need to be selected.

Keywords : hydrogeomorphology; watershed; catchment.

        · abstract in Spanish     · text in English     · English ( pdf )