Guaraguaçu River - Brazil

The Guaraguaçu River is a subtropical tidal coastal river located in Paraná State, Brazil. It spans a pronounced environmental gradient, beginning in a near-pristine floodplain nourished by clean waters from streams originating in a well-preserved mountain range. This region is characterized by the amphibious tree caixeta, a species deeply embedded in traditional cultures for its use in crafting musical instruments, shoes, and boats. As it flows downstream, the river passes through a region affected by human settlement, mining activities, and intense biological invasion by macrophytes. This stretch is paradoxically used both for effluent dilution and as a water source for local municipalities. Further along, the river reaches a well-preserved mangrove area near a major bay, where protected sites and indigenous villages are found along its margins. This final section supports fishing and seafood harvesting, activities deeply rooted in the traditional cultures of local communities.