Banca de DEFESA: THIAGO FARIAS NÓBREGA

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
DISCENTE : THIAGO FARIAS NÓBREGA
DATA : 21/02/2019
HORA: 14:30
LOCAL: Sala de Reuniões, CB
TÍTULO:

USE OF NATIVE SPECIES IN ECOTOXICOLOGICAL ASSAY TO EVALUATE THE WATER AND SEDIMENT QUALITY OF THE DOCE RIVER WATERSHED, RN

PALAVRAS-CHAVES:

Metals; Ecotoxicology; Cladocera culture; Amphipod; Fresh water; Sediment; Semiarid.

PÁGINAS: 159
GRANDE ÁREA: Outra
ÁREA: Ciências Ambientais
RESUMO:

In the Doce River watershed (RDW), Brazilian Northeast, there is an unplanned occupation, pollution and high water deficit. These factors were aggravated by the drought that started in 2012, and lasted for 5 years. Studies already carried out on this watershed showed high levels of anthropization on their shells near the coast (Extremoz Lake and Doce river). However there are few information pertaining to their spring areas, in the Mudo and Guajiru rivers. This research sought to describe the chemical and ecotoxicological characteristics of the water and sediment, of eight reservoirs of water, located in the sub basins of the Mute and Guajiru Rivers, in 2016. In addition, this work proposes the use of Cladocera, that occurring naturally in the watershed, in ecotoxicological studies. This information is divided into three chapters.The first titled " Using Indigenous Cladocera from Doce River Watershed, Northeast of Brazil, as alternatives to exotic organisms in Ecotoxicological Studies.", deployed the culture and described the life story of two native species (Moina micrura and Ceriodaphnia cornuta), compared to a species already standardized and widely used in ecotoxicological studies (Ceriodaphnia dubia). As expected, the species Ceriodaphnia spp. exhibit similar life history variables. In intraspecific comparison, records indicate better results for the cultivation methodology used in this study compared to data available in the literature. It was noticed that M. micrura is more tolerant to the reference substance (NaCl), followed by C. cornuta and C. dubia. The increased tolerance to salinity of native species is a positive factor, with possibility of indication for their use in semi-arid climates, environments in which events of toxicity could be assigned with greater safety to other parameters not to salinity natural, common in reservoirs affected by prolonged droughts. The second chapter "Surface water quality of temporary reservoirs located between the semi-arid region and the Brazilian northeast coast", the aim of this work was to analyze physical, chemical and ecotoxicological characteristics in relation to rainfall, soil occupancy and water quality criteria. It was found that electrical conductivity (EC), hardness, Cd, Ni and chloride were significantly different between the sub basins, this is probably due, different lithologies. The Cd, Pb, Cu and Zn content, present disconformity to quality criteria for the protection of aquatic life, for human consumption and animal breeding. The Pb and EC also showed values higher than those indicated for irrigation. Toxic effects were also observed for the reproduction of M. micrura and Ceriodaphnia silvestrii, which suggests the bioavailability of Pb, Cu and Zn. The third chapter, " Shallow surface water reservoir in the Brazilian semiarid: ecotoxicological and geochemical analysis of sediment.", this study aimed to describe the behavior of metals (Fe, Cd, Ni, Cu, Mn Pb, Zn and Cr), organic matter (O.M.), carbonate and particle size, in relation to climate and lithology. Took into consideration possible toxic effects to the Hyalella azteca e H. meinerti, pollution indicative. It was observed that the behavior of metals over most sampling stations was not significantly affected by anthropogenic activities. However, in the sampling stations with the highest population densification, toxic effects were verified, with mortality higher than the 20%.

MEMBROS DA BANCA:
Interna - 2218942 - IVANEIDE ALVES SOARES DA COSTA
Externa à Instituição - MARIA CRISTINA BASÍLIO CRISPIM DA SILVA - UFPB
Externa à Instituição - ODETE ROCHA - UFSCAR
Presidente - 1298966 - RAQUEL FRANCO DE SOUZA
Interna - 1674709 - VIVIANE SOUZA DO AMARAL