DEPOSITIONAL BARS IN THE FLUVIAL DYNAMICS OF THE CÓRREGO SETE DE SETEMBRO WATERSHED - MATO GROSSO

Abstract

This study analyzes the dynamics of depositional bar formation in the Sete de Setembro Stream, located in the municipality of Reserva do Cabaçal, southwestern Mato Grosso, Brazil, based on well-established principles of Fluvial Geomorphology. The research is grounded on systematic sediment sampling conducted on lateral and central bars along the channel, combined with laboratory grain-size analyses, allowing textural characterization and the interpretation of the active hydrosedimentological processes. The results indicate that the formation of these landforms is directly linked to seasonal variations in discharge, flow energy, and sediment transport capacity. A predominance of medium to coarse sands was observed, along with a significant presence of pebbles in certain reaches, evidencing high hydraulic energy pulses responsible for the remobilization and redistribution of bed material. The alternation between periods of enhanced deposition and sediment remobilization reflects the continuous morphodynamic adjustment of the channel to the hydrological conditions of the basin. Depositional bars thus stand out as important landforms that indicate the current fluvial dynamics, influencing channel geometry, the dissipation of flow energy, and hydro-sedimentological connectivity. This study reinforces the relevance of these features for understanding fluvial processes in headwater environments and for supporting the planning and sustainable management of the Sete de Setembro Stream watershed.