Banca de QUALIFICAÇÃO: JOAO BEZERRA FACUNDO

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
STUDENT : JOAO BEZERRA FACUNDO
DATE: 03/09/2024
TIME: 09:00
LOCAL: https://meet.google.com/wav-mpdv-dmu
TITLE:

RETROSPECTIVE STUDY OF MERCURY BIOACUMULATION IN MARSUPIALS AND RODENTS: ASSESSMENT OF ENVIRONMENTAL CONTAMINATION AND ECOLOGICAL IMPLICATIONS

KEY WORDS:

Small terrestrial mammal, Environmental impact, Madeira River, heavy metal, mining

PAGES: 35
BIG AREA: Ciências Biológicas
AREA: Ecologia
SUMMARY:

This study aimed to determine the mercury concentration in rodents and marsupials collected and rescued from 2012 to 2017 between Nova Mutum Paraná and Porto Velho in the region of direct and indirect influence of the Santo Antônio HPP, Rondônia. The research aimed to analyze the bioaccumulation of mercury in different species of small terrestrial mammals and the possible influence of the environment on these concentration levels. To perform the analysis, 69 hair samples were selected, seven from individuals of the order Didelphimorphia and 62 from the order Rodentia, collected from the dorsal region between the scapulae of the animals. Total mercury (HgT) concentrations were quantified by atomic absorption spectrophotometry coupled to a cold vapor generator. To perform the statistical analysis, the R software version 4.4.1 was used. Descriptive statistics were used in each group to calculate the mean, minimum value, maximum value and standard deviation of the mercury concentrations obtained in the analyzed samples. To assess the normality of the distribution of these concentrations in each group, the Shapiro-Wilk test was applied. In the samples that did not present normal distribution, the Kruskal-Wallis test was performed to identify significant differences in mercury concentrations among the specimens analyzed. The results indicate that rodents have low mercury concentrations with an average of 0.08 mg.kg ¹, probably due to ⁻ their positioning in lower trophic levels, suggesting a lower bioaccumulation of the metal. On the other hand, two individuals of marsupials of the genus Marmosa (2.57 mg.kg ¹) and ⁻ Marmosops, (3.38 mg.kg ¹) presented higher concentrations of HgT. Within the order ⁻ Rodentia, the genus Nectomys had the highest HgT concentration with 0.32 mg.kg ¹. ⁻ Analysis of HgT concentrations revealed that, in general, the observed levels were relatively low. This trend of low concentrations can be attributed to the fact that rodents occupy lower trophic levels in the food chain. To understand the variations in HgT levels among species, it is essential to examine specific details. Diet plays an important role in the amount of accumulated mercury; insectivorous marsupials may have higher mercury levels when compared to frugivores and granivores. In addition, the interaction between the environment and the animals' diet is complex, with the ingestion of contaminated food reflecting on mercury levels. Investigations into the diet and habits of these animals in the region are necessary to understand these dynamics and develop strategies to protect wildlife and human health.

COMMITTEE MEMBERS:
Presidente - 1427035 - WILSON GOMEZ MANRIQUE
Interno - 359961 - WANDERLEY RODRIGUES BASTOS
Externo ao Programa - ***.574.687-** - JOSEPH ALBERT MEDEIROS EVARISTO - UENF