Poster Presentation Society for Freshwater Science 2026 Annual Meeting

Effects of deforestation on water quality, with a focus on Total Organic Carbon (TOC), from Amazon streams (135805)

Flávio H. Souza 1 , Sylvia H. Masuno 1 , Gabriel O. Ferraz 2 , Silvio F. Ferraz 2 , Leonardo T. Maeoka 2 , Debora R. Carvalho 3 , Cecília G. Leal 3 , Ricardo H. Taniwaki 1
  1. Universidade Federal do ABC - UFABC, Santo André, São Paulo, Brazil
  2. Departamento de Ciências Florestais, Escola Superior de Agricultura “Luiz de Queiroz”, Universidade de São Paulo, Piracicaba, São Paulo, Brasil
  3. Lancaster Environment Centre, Lancaster University, Lancaster, England

Deforestation in the Amazon region has increased over the decades, with one of its main impacts being the destruction of vegetation cover due to agricultural activities. These land-use changes can affect carbon concentrations in the fluvial systems that are part of this biome. Therefore, the study aimed to identify areas vulnerable to environmental degradation and to understand how deforestation and land use influence carbon dynamics. Sampling was conducted between July and August 2024 in forty eight streams, and samples were analyzed  using a dissolved carbon analyzer (TOC-L, Shimadzu, Japan). Results showed a tendency toward higher carbon concentrations in forested areas, although no statistically significant differences were detected (p = 0.1), possibly related to subsurface carbon inputs or anthropogenic carbon inputs in deforested areas. Overall, the findings indicate that multiple factors control carbon dynamics in Amazonian streams and, consequently, water quality, reinforcing the importance of continuous, integrated monitoring to support sustainable management of Amazonian water resources.

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