Banca de QUALIFICAÇÃO: MATEUS AUGUSTO DE CARVALHO SANTANA
Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.STUDENT : MATEUS AUGUSTO DE CARVALHO SANTANA
DATE: 29/11/2024
TIME: 14:00
LOCAL: Google Meet
TITLE:
WATER AND SEDIMENT QUALITY IN URBAN WATERSHEDS IN THE EASTERN AMAZON
KEY WORDS:
Environmental contamination; potentially toxic elements; human health risks; environmental risks.
PAGES: 50
BIG AREA: Ciências Agrárias
AREA: Agronomia
SUBÁREA: Ciência do Solo
SPECIALTY: Química do Solo
SUMMARY:
Several cities have been impacted by increased urbanization and industrialization in the Amazon, including the inappropriate discharge of effluents and household waste into the environment, which can compromise water quality and cause contamination by potentially toxic elements (PTEs) in urban watersheds. The study aimed to: i) characterize water quality parameters; and ii) determine the concentrations of PTEs in sediments from representative watersheds in the city of Belém, eastern Amazon. For this purpose, water and sediment samples were evaluated at 81 points, including 76 points in anthropized watersheds: Armas (ARM), Estrada Nova (ENO), Icoaraci (ICO), Mata Fome (MTF), Murucutum (MUR), Paracuri (PCR), Tamandaré (TAM), Tucunduba (TUC), Una (UNA), and Val-de-Cães (VAL); and 5 points in a reference water body (CHR). Water samples were collected using Van Dorn bottles and sediment samples using an Ekman-Birge sampler. Water was evaluated for temperature, pH, dissolved oxygen (DO), total dissolved solids (TDS), and electrical conductivity (EC) using a multiparameter probe. The concentrations of PTEs in sediments were extracted by acid digestion and quantified by microwave-induced plasma atomic emission spectrometry. Water quality parameters and PTE concentrations in sediments were interpreted based on the values defined in resolutions 357/2005 and 454/2012 of the Brazilian National Environmental Council (CONAMA). The results were statistically compared using the Kruskal-Wallis and Dunn tests (p < 0.05) to identify possible differences between watersheds. Temperature was lower in the TUC, VAL, and CHR watersheds. All watersheds presented pH within the range recommended by Brazilian legislation (6–9). The DO concentration was below that recommended by CONAMA (5 mg L−1) in all watersheds, except in the reference area. The TDS levels were below the limit defined by CONAMA (500 mg L−1), especially in CHR, with values statistically below the other watersheds. The EC was also lower in CHR (38.67 μS cm−1) than in the anthropized watersheds, especially when compared to ICO, which presented 476.67 μS cm−1. For sediments, CHR presented all PTEs at concentrations below the level 1 established by CONAMA, suggesting a low risk of adverse effects to the biota. On the other hand, concentrations above this limit were observed for copper in ARM, ICO, TAM, and UNA, cadmium in ARM, ENO, ICO, MUR, PCR, TAM, TUC, UNA, and VAL, chromium in ARM, lead in TAM, and zinc in ARM, ICO, and TAM, indicating the need for special monitoring. The results of this study highlight the impacts of anthropogenic activities on water and sediment quality in watersheds in the city of Belém, host of the 30th United Nations Climate Change Conference (COP30). Our study provides important information for the development of policies aimed at mitigating environmental damage and protecting the health of the ecosystem and population in the eastern Amazon.
COMMITTEE MEMBERS:
Presidente - 6388356 - ANTONIO RODRIGUES FERNANDES
Externo à Instituição - MARCIO SOUSA DA SILVA - ITV
Externo à Instituição - JOSÉ TASSO FELIX GUIMARÃES: - ITV