Estudo sobre a evolução do aporte natural e antrópico de matéria orgânica para sedimentos de um sistema estuarino- lagunar tropical (Mundaú-Manguaba, Alagoas) utilizando lipídios como marcadores moleculares

• Autor(a) principal: Araujo, Michelle Passos
• Data de Publicação: 2010
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da UERJ
• Texto Completo: http://www.bdtd.uerj.br/handle/1/13915
• topic: Organic matter; Lipids; Core; Fecal contamination; Molecular markers; Matéria orgânica; Lipídios; Testemunhos; Contaminação fecal; Marcadores moleculares; CNPQ::CIENCIAS EXATAS E DA TERRA::OCEANOGRAFIA::OCEANOGRAFIA QUIMICA

This thesis presents a study on the accumulation of organic matter in the sediments of the complex estuarine lagoon Mundaú Manguaba (CELMM) using lipids (fatty acids, sterols and linear alcohols) as molecular markers to evaluate the sources (natural and anthropogenic) and spatial and temporal variation in the composition of sedimentary organic matter, as well as the influence of diagenetic processes on the quality and preservation of it. The CELMM is characterized by a high potential for recycling and storage of materials and is subject to various anthropogenic activities, including urbanization and practice of monoculture of cane sugar, in addition to suffering an accelerated process of environmental degradation. By multivariate analysis was possible to discern sources of lipids, and from this, identify the contributions of organic matter - plankton (phytoplankton and zooplankton), terrigenous and bacterial - for different sectors CELMM. It was possible to identify an increase in the accumulation of organic matter of autochthonous origin in the lagoons in recent years. This effect was more significant in Mundaú, reflecting the higher level of anthropogenic disturbance at the pool. The level of fecal contamination - assessed through fecal sterols - may be considered medium to low compared with other sites that also have significant human influence. The diagenetic transformation of organic matter as measured by the reasons stanol / sterol, showed that bacterial activity in CELMM is significant even in the water column or sediment-water interface, but that after the burial of organic matter is preserved.