Banca de QUALIFICAÇÃO: EDVAGNER DE OLIVEIRA

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
DISCENTE : EDVAGNER DE OLIVEIRA
DATA : 30/07/2024
HORA: 14:00
LOCAL: CELBE e de forma remota
TÍTULO:

EFFECTS OF CASCADE HYDROELECTRIC DAMS ON MERCURY ACCUMULATION IN BIOTIC AND ABIOTIC COMPARTMENTS IN THE AMAZON

PALAVRAS-CHAVES:

Bioaccumulation; Cascade hydropower; Total mercury,

PÁGINAS: 80
GRANDE ÁREA: Outra
ÁREA: Ciências Ambientais
RESUMO:

Mercury (Hg) is a global pollutant and ranks among the top ten most harmful pollutants, being the third most concerning for human health. In biota, especially in aquatic biota, Hg causes neurological, physiological, and reproductive adversities. Aquatic environments, particularly lotic systems such as hydroelectric reservoirs, amplify contamination by this metal. The global and Brazilian energy demand has led to the creation of numerous hydroelectric power plants, including four plants with large cascading reservoirs on the Teles Pires River, a tributary of the Tapajós Basin in the Brazilian Amazon. Contaminations by Hg were analyzed in predatory and non-predatory fish, sediments, and soil downstream and in the Sinop, Colíder, Teles Pires, and São Manoel reservoirs. This study also includes control points on the Teles Pires River and the Juruena River. This thesis is presented in two articles and aims to evaluate the effect of hydroelectric reservoirs on fish, sediments, and soil. The first article presents an analysis of Hg contamination in predatory and non-predatory fish from the four hydroelectric reservoirs on the Teles Pires River. Predatory fish downstream showed higher concentrations compared to the reservoirs. There was also an increase in Hg concentrations along the river flow, when comparing only the reservoirs. Approximately 53% of the reservoir fish were above the 500 μg kg-1 w.w. limit recommended by the WHO, while 89% downstream exceeded this limit. Non-predatory fish showed no amplification trend, being similar in the sampled environments. The second article presents an analysis of total mercury (THg) in sediments and soil from the four hydroelectric reservoirs on the Teles Pires River. Sediments from the hydroelectric reservoirs showed higher THg concentrations compared to their downstream directly. We also observed that total THg concentrations in sediments increased following the river flow. The lateral soils of the hydroelectric reservoirs increased following the flow of the reservoirs, from the Sinop reservoir to the Teles Pires reservoir, decreasing at the last sampling point (São Manoel reservoir). There is a positive trend between THg concentrations in soil and sediment, suggesting possible Hg transfer during reservoir filling.

MEMBROS DA BANCA:
Presidente - 83200001 - AUREA REGINA ALVES IGNACIO
Externo à Instituição - JOAO HENRUQUE FERNANDES AMARAL - UR
Interno - 71440008 - MANOEL DOS SANTOS FILHO
Interna - 110049004 - MARIA APARECIDA PEREIRA PIERANGELI
Externa à Instituição - THAÍS DE CASTRO PAIVA - UFMG