This proposal aimed to study the carbon dynamics, describing the biogeochemical cycle in Santos Estuarine System (SES), verifying the correlation between the organic and inorganic forms of carbon within the aquatic ecosystem, and identify associations between the various carbon and the effluent resulting from human activity. The SES was chosen for the study due to strong exposure of the environmental impacts of various origins, including steel, plaster and paper mills; cement and fertilizer factories; chemical, petrochemical and metallurgical industries; the most important port of the Latin...