Unidades Geomorfopedológicas da bacia hidrográfica do Ribeirão das furnas (Indianópolis - MG).

Abstract

The geomorphological approach contributes to understanding the evolution of the relevance and spatial distribution of soils, integrating geological, geomorphological and pedological data. The Ribeirão das Furnas watershed, located in the mesoregion of Triângulo Mineiro and Alto Paranaíba, is located in the municipality of Indianópolis and plays a significant role in the region's productive agricultural system. Furthermore, its drained area is home to a high percentage of the Indianópilis-Celso Bueno plateau, which has elevation levels level with the Uberaba-Uberlândia plateau, consistent with the South American Surface. Its set of lands presents a geomorphopedological context marked by tabular tops and erosive scarps, with different lithotypes that control the dynamics of the areas relief and soils. This variation results in the formation of different classes of soils, which range from less developed soils such as Neossolos, to thick latosolized profiles and hydromorfic soils in a veredas environment. With this, the research aimed to identify the geomorphopedological units of the Ribeirão das Furnas watershed, in order to contribute to the genetic discussion on relief and soils, as well as to create data that support environmental planning. The methodology was guided by the first two levels of approach of the morphopedological compartmentalization proposal, originating from French geomorphologists and adapted by Brazilian geopedology. At the first level, bibliographical and cartographical reviews were carried out, followed by the organization of intermediate mappings, which were later used to identify geomorphopedological units on a 1:50,000 scale. The second level involves field work to arrive at previously organized mappings, as well as for the morphological description of soil profiles, with sample collection for granulometric and morphoscopic analyses. Still at this second level, fieldwork supported the production of a longitudinal section (transect) and a block diagram that intersects the units mapped at the first level. In its results, the work addressed the influence of relevance on soil formation, therefore presenting the identification of the following geomorphological compartments positioned in the Morphostructural unit of the Paraná Sedimentary Basin: Wide Tabular Interfluves (I), Extended Smoothly Convexized Slopes (II), Aptf (III), Convexized Stepped Slopes (IV) and Embedded Valleys (V). Secondly, associating these geomorphological compartments with the lithological and pedological framework, four geomorphological units were recognized: the Gleizada and Paludizada Humid Unit (I); to the Wide Interfluves and Smoothly Convexized Latossolized Slopes (II); as stepped slopes with outcrops and pedogenized colluvium ramps (III); and the Regolithic and Rocky Encased Valleys (IV). The work also presents in its results the genetic discussion on different Oxisols identified in the area as LA, LV1 and LV2, specifically with the geomorphic surfaces, the source materials and the morphological and experimental data (genulometry and morphoscopic). With this, it is understood that the spatial distribution of soils in the Furnas river basin has a direct connection with the evolution of geomorphic surfaces (S1, S2 and S3) and with the development and mobilization of alteration profiles originating from different lithotypes ( Cenozoic covers, rudaceous and basaltic deposits).