RESUMO
River sediments have the capability to accumulate and absorb traces of anthropic environmental degradation. In this work, we investigated the effects of urban land use on the composition of physical sediment. For this purpose, sediment profiles were collected in the wet and dry seasons and in locations with mixed land-use. For the sediment analysis, particle size separation, organic matter degradation, visual analysis of the thickest fraction using a magnifying glass and stereomicroscope analysis of the particle size material corresponding to the sands were performed. It was observed that the sedimentation of synthetic materials and plastics (fragments and fibres) were the most frequently found materials. More intense urban occupation areas and with less riparian vegetation suffer more from this degradation than rural areas or areas with preserved riparian vegetation. The dam in the basin accumulates more materials (macro and microplastics) and has the role of containing and preventing these residues from being transported downstream. The importance of investing in environmental management measures is emphasized, and based on the sampled sites assessed, the restoration of riparian vegetation, greater inspection of inadequate waste disposal and public cleaning actions are suggested, including actions in the Tibiriçá dam.