2019-09-042019-09-042014NOBRE, Ana Carolina Lemos. Caracterização hídrica e sedimentar da sub-bacia de Melgaço – Pará. Orientador: Marcelo Rollnic. 2014. 66 f. Trabalho de Curso (Bacharelado em Oceanografia) - Faculdade de Oceanografia, Instituto de Geociências, Universidade Federal do Pará, Belém, 2014. Disponível em: http://bdm.ufpa.br/jspui/handle/prefix/1960. Acesso em:.http://bdm.ufpa.br/jspui/handle/prefix/1960The Amazon region is composed of a series of dense and complex drainage networks that are responsible for transporting a large amount of water and sediment to the Atlantic Ocean. Among these drainage networks can cite the Portel / Melgaço basin, located in the intermediate between the Amazon and Tocantins/Araguaia basins. A few studies have been conducted in this region, especially those related to local hydrodynamics. Thus, the objective of this work is to analyze the water and sedimentary contribution of thePortel/Melgaço basinto the Marajó Bay. With this proposal, collections were made in the region of Melgaço (Portel/Melgaço basin) in two separate campaigns: June 2013 and March 2014, where campaigns were conducted over a tidal cycle (13 hours) for measuring tide, turbidity, suspended particulate matter (SPM), bathymetry profile and water balance. The tide was measured with a pressure sensor (Datalogger) anchored in the collection site. Turbidity was measured with an OBS (Optical Backscatter Sensor) and the MPS sensor was measured by filtering water (collected with a Van Dorn bottle) by gravimetric method; both by performing vertical profiles through the two margins and the middle of the river. The water balance was measured by the realization of cross-sections from one margin to other with a current profiler (ADCP). The bathymetric profiles were done with the aid of an echo sounder, making a mesh previously established with 200 meters of distance between each bathymetric profile. In the first campaign the tide height was 0.66 meters and in the second, 0.56 meters, which is a variation of 0.10 meters between the campaigns. The bathymetric profile showed great variation between the left margin (city Melgaço-PARA), with an average of 1meter, and the right margin and middle of the river (where is located the main channel), where the maximum obtained was 27 meters. In the first campaign the turbidity values of the right margin and middle of the river were higher than those of the left margin. In this period the average turbidity was 24 FTU and 27 FTU, respectively for surface and bottom; the average of ebb tide was 12 FTU and 10 FTU for the flood. The MPS in this campaign were higher in the botom and lower in the surface, with an average of 3 mg.L-1 and 9 mg.L-1for surface and bottom, respectively; the ebb and flow average were 4mg.L-1 and 7 mg.L-1, respectively. The water balance analysis showed that in this collection period occurred the entry of water into the Portel/Melgaço basin, with the mean for the tidal cycle of -822 m3.s-1. The longitudinal velocity (ū) was higher in this campaign, with a maximum value of 0.4 m.s-1. In the second campaign the turbidity values were lower than in the first, with the right margin presenting the highest values. The average for surface and bottom were, respectively, 5 FTU and 9 FTU and the means of ebb and flood tide were similar (5 FTU). The values of MPS in this period were higher than in the first campaign. The averages for surface and bottom were, respectively, 5 mg.L-1and 12 mg.L-1; the ebb and flood tide averages were 10 mg.L-1, 7 mg.L-1. The water balance showed that in this campaign occurred the water output of the basin, with an average of 622 m3.s-1. The longitudinal velocity (ū) had maximum value of 0.3 m.s-1, being lower compared to the first campaign. Thus, the variation of parameters analyzed is mainly influenced by the inflow and outflow of water from the basin, which can be derived from Portel/Melgaço basin orfrom the Amazon basin.Acesso AbertoBalanço hidrícoMelgaçoTurbidezCNPQ::CIENCIAS EXATAS E DA TERRA::OCEANOGRAFIA::OCEANOGRAFIA GEOLOGICATrabalho de Curso - Graduação - Monografia