Título: | PREDICTING MERCURY CONCENTRATION IN TUCUNARÉ USING MASS BALANCE AND BIOENERGETICS | |||||||
Autor: |
YSRAEL MARRERO VERA |
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Colaborador(es): |
ROBERTO JOSE DE CARVALHO - Orientador ZULEICA CARMEN CASTILHOS - Coorientador MARIA JOSEFINA REYNA KURTZ - Coorientador |
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Catalogação: | 18/MAR/2005 | Língua(s): | PORTUGUESE - BRAZIL |
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Tipo: | TEXT | Subtipo: | THESIS | |||||
Notas: |
[pt] Todos os dados constantes dos documentos são de inteira responsabilidade de seus autores. Os dados utilizados nas descrições dos documentos estão em conformidade com os sistemas da administração da PUC-Rio. [en] All data contained in the documents are the sole responsibility of the authors. The data used in the descriptions of the documents are in conformity with the systems of the administration of PUC-Rio. |
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Referência(s): |
[pt] https://www.maxwell.vrac.puc-rio.br/projetosEspeciais/ETDs/consultas/conteudo.php?strSecao=resultado&nrSeq=6133&idi=1 [en] https://www.maxwell.vrac.puc-rio.br/projetosEspeciais/ETDs/consultas/conteudo.php?strSecao=resultado&nrSeq=6133&idi=2 |
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DOI: | https://doi.org/10.17771/PUCRio.acad.6133 | |||||||
Resumo: | ||||||||
The mercury used in the artisanal mining (garimpo) of
gold in the Amazon
region is emitted to the atmosphere, soil and rivers. Once
in the atmosphere, the
metal is oxidized and immediately deposited. In the water,
the transformation to
methylmercury takes place mostly due to the action of
microorganisms. The
formation of methylmercury increases the dispersion and
bioavailability of the
element in the aquatic environment. The methylmercury can
be assimilated by
the plankton and enters the food chain. The concentration
of the metal increases
further up in the trophic levels of the chain and reaches
the highest values in
carnivorous fishes like tucunaré. Thus, the mercury
emissions cause the
contamination of natural resources and enhance the risks
to the health of regular
fish consumers. The objective of this work is to test a
model for bioaccumulation
of mercury in fishes. The model calculates concentrations
in top predators of the
food chain and can be used as a tool for the management of
aquatic ecosystems
potentially contaminated with mercury. This objective was
accomplished through
the combination of the Trudel mass balance and Wisconsin
bioenergetics
models, applied to tropical species of the Cichla
(tucunaré) genre of the Tapajós
river basin. The Wisconsin bioenergetics model was
utilized to determine the
rates of food consumption from estimated fish growth data.
The parameters used
in the models were found in the literature. The ability of
the models to predict
mercury contents in tucunarés was evaluated by comparison
with the field data,
obtained in 1992 and 2001, in the Tapajós River and in the
Maicá lakes. The best
results were attain ed for specimens collected in 1992
what seems to be related to
a better estimate of mercury concentration in the food in
this year.
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