Using environmental conservation units as reference for evaluating contamination in river basins - Silva, Paulo Roberto Bairros da; Iglesias, Camilo Jose Viera; Parizotto, Denise; Cruz, Lurian Aparecida Domingos da; Dressler, Valderi; Minella, Jean Paolo Gomes; Schnitzler, Danielle Caroline; Mauad, Frederico Fábio (Journal of South American Earth Sciences, 2025)