Banca de DEFESA: LYNDYANNE DIAS MARTINS

Uma banca de DEFESA de MESTRADO foi cadastrada pelo programa.
DISCENTE : LYNDYANNE DIAS MARTINS
DATA : 17/03/2021
HORA: 09:00
LOCAL: GOOGLE MEET
TÍTULO:

FLOW OF METALS IN PARTICULATED MATERIAL IN SUSPENSION: CONTRIBUTION TO MONITORING OF ENVIRONMENTAL CHANGES IN THE DELTA DO RIOPARNAÍBA

PALAVRAS-CHAVES:

Flows and mass balance, MPS, Trace Metals, Delta do Parnaíba.

PÁGINAS: 66
GRANDE ÁREA: Outra
ÁREA: Ciências Ambientais
RESUMO:

The determination of MPS in estuarine waters comprises valuable information, since it this geochemical fraction has a high capacity to adsorb pollutants. Main objective of this research was to quantify the flows of Cadmium (Cd), Cobalt (Co), Lead (Pb), Zinc (Zn),, and Ferro (Fe) associated with MPS in the waters of the Parnaíba Delta estuarine system under prolonged drought condition. A sampling campaign carried out at low tide quadrature (September 2019) included a spatial (Langrangean) and temporal evaluation (Eureliana) in tidal cycle (ebb / flow). The parameters pH, dissolved oxygen (DO), oxygen saturation (% OD), temperature (T), salinity (PSU) and electrical conductivity (Ec) were determined in situ with portable multisort. In the laboratory, concentration of MPS by gravimetry and the trace metals associated with it, for flame atomic absorption spectrophotometry. Multivaried chemometric analyzes (PCA and HCA) were used to infer the origin and behavior of trace metals and the interrelationships with physical-chemical parameters. From the flow calculation, it was proposed a mass balance aiming to estimate the net discharges of MPS and trace metals between the estuary and the adjacent coast. The hydrochemical parameters were found to be similar for the two tide regimes analyzed, with pH, OD, Ec and S values, with an upward trend following the fluvial-marine gradient. The mean values of MPS ranged between 0.01 and 0.71 mg / L for the flood tide and 0.02 and 0.81 mg / L for the ebb tide, presenting values lower than those reported for tropical estuaries on the Brazilian northeast coast. Iron was the most detected metal in the campaign with average concentrations ranging from 0.74 to 30.89 mg / kg in the flood tide and 0.85 to 33.52 mg / kg in the ebb tide, presenting concentrations higher at the points closest to the mouth of the river, especially at Point 3. The balance sheet estimates showed that the estuary of the Parnaíba River retains both the levels of MPS (104.9 ton / day) and trace metals Cd (5.55 g / day), Co (4.74 g / day), Pb (0.27 kg / day), Zn (2.10 kg / day), Fe (4.03 kg / day), thus serving as a material drain.

MEMBROS DA BANCA:
Presidente - 1513585 - FRANCISCO JOSE DE PAULA FILHO
Interno - 1751179 - PAULO RENATO ALVES FIRMINO
Externo à Instituição - FRANCISCO JOSE DA SILVA DIAS - UFMA