IDENTIFICATION OF RIVER STYLES IN THE RIACHO GRANDE WATERSHED, ALAGOAS
Landscape Connectivity; Fluvial Geomorphology; River Environment
Fluvial dynamics acts as one of the main agents in the sculpting of the landscape, through mechanisms of erosion, transport and sediment deposition that shape forms together with a complexity of numerous active processes. The so-called dry lands present a surprising paradox: while they present a scarcity of precipitation, their landscapes are configured as a product of fluvial action. Several methodologies can be applied to understand these dynamic and non-linear river environments. Thus, this research makes use of the Fluvial Styles methodology, which proposes to use various temporal and spatial scales in a holistic way, dividing the channels into fluvial typologies to understand their character and behavior. Despite the possibility of working through multiple scales, the research is restricted to stretches of the main channel of the Riacho Grande watershed in the contemporary period, taking into account the fluvial morphologies and how they respond to the geological context and the history of land use and occupation in the basin. The use and occupation of land is one of the main points of the analysis of this methodology, since human interferences cause imbalances in the river landscape, which are expressed through changes and creation of associated forms, such as bars and floodplains. The main objective is based on the application of fluvial typologies proposed for the construction of knowledge about the character and behavior of the river and to understand how the channel responds both to the configuration of the natural physical environment and to human influences. Thus, in addition to the fluvial styles methodology, the work relies on the application of morphometric parameters that can indicate the structural and lithological control in the configuration of the highlighted landscape, such as the Slope-Length Index (SL Index) and the sinuosity index for indicate deposition environments. To define the typologies, land use and land cover mapping, geomorphological mapping and landscape units are also used. In this way it will be possible to trace relationships between fluvial dynamics and its interference by anthropogenic factors.