Avaliação do processo de assoreamento no Porto de Tubarão, Vitória-ES

• Ano de defesa: 2021
• Autor(a) principal: Neves, Rafael Carvalho
• Tipo de documento: Dissertação
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal do Espírito Santo; BR; Mestrado em Oceanografia Ambiental; Centro de Ciências Humanas e Naturais; UFES; Programa de Pós-Graduação em Oceanografia Ambiental
• Palavras-chave em Português: Assoreamento; hidrodinâmica; batimetria; sedimentologia; geoquímica; isótopos; agrupamento de observações; portos; dragagem; subject.br-rjbn; Ciências Ambientais
• Link de acesso: http://repositorio.ufes.br/handle/10/14117

The importance of Brazilian waterways and ports for the country's foreign trade and the growing demand for improving port infrastructure to increase Brazil's competitiveness in the world inspired the main objective of this study to evaluate the siltation process in the Tubarão Port, Vitória-ES. Due periodic maintenance dredging necessity to keep its maritime area navigable, the understanding improvement of sedimentary dynamics in Tubarão Port area is imperative, in order to provide scientific basis for discussions, such as planning dredging projects and navigation safety. Starting from the integrated analysis of historical precipitation in Vitória-ES, flow in the Santa Maria da Vitória River and hydrodynamic and sedimentary data from Vitória Bay (BV) and Espírito Santo Bay (BES) and later integrating with bathymetric evolution between 2015 and 2018 at Tubarão Port, it was possible to identify the resulting flow from BV to BES as the main source of sedimentary material in the region. During the low precipitation period, between June 2015 and April 2017, there was a lower siltation rate in the port area (0.02 m/year) due the small sedimentary material supply from BV and the adjacent coastal region. While between May 2017 and April 2018, the highest siltation rate was observed in the port area (0.35 m/year) due the increased rainfall and currents acting preferentially to NE/E at BES, associated with rise of SE/S waves frequency. The sedimentological and geochemical results of the 91 superficial sediment samples collected at BES and the surrounding areas were analyzed by Cluster Analysis with distribution the samples into 4 statistically different groups. The high levels of organic matter (MO), total organic carbon (COT), total nitrogen (NT) and nitrogen stable isotope (δ15N), such as high carbon to nitrogen (C/N) ratio observed in all BV and Passagem Channel (CP) areas suggest the anthropized terrestrial sediment predominance in this region. At BES, the sediment found in inner portion near Camburi beach is trapped in this region due the action of rock outcrop, present in the central region, as an obstacle to sediment effective exchange between the innermost and outside bay areas. In central and external areas of BES, there is a mix between marine and terrestrial sediment from BV. The COT and NT high values found in the sediment inside the port’s channel also suggest the MO and fine sediment contribution from BV to the Tubarão Port area. Results and discussions presented in this study show the continuous meteo-oceanographic and sediment quality monitoring importance as basis for understanding the complex sediment dynamics observed in port regions.