Banca de QUALIFICAÇÃO: TARSSIA ALVES FERREIRA

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
STUDENT : TARSSIA ALVES FERREIRA
DATE: 29/09/2023
TIME: 14:00
LOCAL: Campus VI
TITLE:

NICHES CONSTRUCTED WITH FUNGAL BIOCOMPOSES: evaluation of ecotoxicity, mechanical properties and bioreceptivity

KEY WORDS:

Potentially Toxic Elements; germination; Acid leachates; Iron ore tailings.

PAGES: 52
BIG AREA: Outra
AREA: Multidisciplinar
SUMMARY:

The Constructed Niche (CN) is an ecological alternative proposed for the environmental recovery of areas degraded by iron mining. The technique aims to mimic pre-existing ecological niches, since they are made up of soil from the area to be restored, with the addition of iron ore tailing and an agglomerating agent. Among binders, biocomposites produced by microorganisms have been shown to be a sustainable choice over other synthetic polymers and cement. The present study aimed to evaluate the presence of potentially toxic elements in the CN constituents and the mechanical resistance of specimens of the CNs with fungal mass biocomposite. Leaching and phytotoxicity tests were carried out involving materials such as topsoil and iron ore tailings, and with CNs (mixture of topsoil, tailings and binders) using various acid extractors. The leachates obtained were submitted to analysis by atomic absorption spectrometry, resulting in the determination of the following elements: Fe, Al, Mn, Pb, Cu, Zn, Ni, Cd and Cr. Phytotoxicity was evaluated by germination test with plants and mechanical resistance by compression test. The concentrations of the quantified chemical elements were below the reference values established by CONAMA/COPAM. It should be noted that the elements Fe, Al and Zn are not subject to specific regulations, since they are natural constituents of the soils of the Iron Quadrangle. The contents of these metals did not significantly affect the germination of vegetable seeds, as the percentage of germination was greater than 70%, except for the leachate with acetic acid (pH 2.74). It is believed that germination inhibition and prolonged germination time are related to the acidic characteristics of the leachate. Furthermore, CNs with biocomposite in different proportions (5%, 10% and 15%) exhibited compressive strength four times lower than cement CN. The results obtained showed that the use of waste does not provide biotoxicity in CNs, however, the use of fungal mass as a binder still needs further studies.

COMMITTEE MEMBERS:
Presidente - LUZIA SERGINA DE FRANCA NETA
Externa ao Programa - ADRIANA DE ALMEIDA PINTO BRACARENSE