Faculdade de Oceanografia - FAOCE/IG
URI Permanente desta comunidadehttps://repositorio.ufpa.br/handle/2011/2802
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Navegando Faculdade de Oceanografia - FAOCE/IG por Autor "MONTEIRO, Sury de Moura"
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Item Acesso aberto (Open Access) Dinâmica sazonal de nutrientes em estuário amazônico(2015-04) MONTEIRO, Sury de Moura; EL-ROBRINI, Maâmar; ALVES, Igor Charles CastorThis paper shows the nutrients distribution in the Paracauari estuary over a Amazon hydrological cycle (2008), and at the end of the period of La Niña (April 2008). This estuary is influenced by the humid tropical climate and meso-tidal (3 to 4 m), semi-diurnal. Sampling was conducted at 10 stations in three distinct seasons: rainy (march), intermediate (june) and less rainy season (september). Were measured in situ physical and chemical parameters using a multiparameter probe; analyzed the dissolved nutrients (nitrate, nitrite, ammonia- -N, phosphate and silicate) by spectrophotometry and particulate matter suspension, gravimetrically. We observed large seasonal variations in the concentrations of the studied parameters. The water temperature (average of 28.58 °C) is quite homogeneous, typical of tropical waters. The pH ranged acid (5.80) to alkaline (7.86) and salinity between 0.06 to 7.56, with both maximum values at the mouth because of the greater marine influence. The waters are poorly oxygenated during the rainy season (2.35 mg.L-1) and at the very least rainy (6.55 mg.L-1). The concentrations of the suspended particulate matter and nutrients reached a maximum during the rainy season due to the natural inflow from adjacent areas. In this estuary, the nutrients are mainly controlled by the river discharge, rainfall, wind and tide and exceptionally by la Niña.Item Acesso aberto (Open Access) Geochemistry of suspended particulate matter in a tropical estuarine system, southeastern Brazil(Universidade Federal do Pará, 2017-09) MONTEIRO, Sury de Moura; SÁ, Fabian; RODRIGUES NETO, RenatoThe aim of this study is to assess the variation of the geochemistry of suspended particulate matter (SPM) in the tropical estuarine system composed of the adjacent Piraquê-Açu and Piraquê-Mirim (ES) rivers using SPM sampled with sediment traps (45 µm mesh) installed in the drainage channels. We collected SPM during different tidal stages and seasonal periods and analysed the metals using inductively coupled plasma mass spectrometry according to EPA 3051A, the mineralogy using X-ray diffraction, the particle size using laser ray diffraction, and organic matter (OM) using calcination. The traps collected enough SPM to perform analyses for each sampling period. The SPM consists of silt size particles, and the percentage of OM is between 20 and 40%. The particles are dominated by kaolinite and quartz, and gibbsite, haematite, goethite, and pyrite are also present. These materials are found in the Barreiras Formation, through which the drainage system cuts. The metal concentrations were higher in the summer: Al (3208.32 g kg-1), Pb (28.05 mg kg-1), Mn (676.35 mg kg-1), Cr (136.12 mg kg-1), and Cu (13.76 mg kg-1). The Piraquê-Açu River had higher metal concentrations than the Piraquê-Mirim River, and the geochemical indices of both rivers indicate that they naturally contribute to the estuarine system of the Piraquê-Açu and Piraquê-Mirim rivers (SEPAPM). However, anthropic interferences influence these indices at the confluence of the two channels.