Banca de QUALIFICAÇÃO: MARIANA DE AGUILAR SANTOS

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
STUDENT : MARIANA DE AGUILAR SANTOS
DATE: 30/11/2021
TIME: 14:00
LOCAL: Campus VI - Mestrado de Tecnologias de Prodiutos e Processos
TITLE:

EVALUATION OF CHEMICAL AND BIOLOGICAL ATTRIBUTES OF CONSTRUCTED NICHES USING IRON ORE TAILING: an alternative for the revitalization of degraded areas.

KEY WORDS:

Constructed niche, iron ore tailings, bentonite clay and fungi biocomposite.

PAGES: 70
BIG AREA: Outra
AREA: Multidisciplinar
SUMMARY:

The iron ore extraction industry is one of the important sectors for the Brazilian economy, standing out in the Quadrilátero Ferrífero region in Minas Gerais. This activity generates a significant environmental impact in Campos Rupestres (CR) and the disposal of the generated tailings is a current socio-environmental problem, especially after the collapse of the two tailings dams in the state. The use of Constructed Niche (NC) is a technique recently presented, which has as its constituent iron ore tailings, topsoil and binder. The application of the CN technique aims to mimic pre-existing ecological niches in areas degraded by mining activity, by bringing biotic components from the area of interest. So far, this study aimed to characterize the topsoil of a non-degraded area of CR in terms of chemical and mineralogical composition (DRX and FRX) and fertility; evaluate the effects of new CN constituents (such as bentonite clay and fungal mycelium biocomposite) on their mechanical properties and biological attributes, such as: microbial biomass carbon (MBC), basal respiration (BR) and metabolic quotient (qCO2 ); observe the presence of photobionts organisms during the incubation period with a maximum duration of 180 days; and extracting topsoil DNA to characterize microbial diversity. The CNs were made by adding different proportions of topsoil from the Serra da Piedade CR, iron ore tailings (30%), cement (5%), clay (10%) and biocomposite (10%). Topsoil RDX and FRX analyzes showed mineralogical components such as hematite, quartz and goethite and high proportions of iron oxide and silicon dioxide. Fertility analyzes showed low concentration of nutrients, including Ca, K and P, and acidic pH. These features observed are typical of CR topsoil from geological sites in the QF region. The new binders used in the CNs did not provide resistance to the material and new proportions of these binders should be tested in future studies. Higher values of MBC and BR were observed in the clay and biocomposite modules after seven days of incubation, indicating that these binders do not affect the presence of life after their manufacture. The opposite was observed in the modules with cement. The growth of photobionts such as bryophyte gametophyte and angiosperm seedlings in the topsoil and topsoil+tailings samples, and of fungi were observed in the CNs with 60 days of incubation. DNA was extracted from topsoil and will be sequenced using some markers such as ITS and 16S, to assess microbial biodiversity. After 180 days, new analyzes of fertility and biological attributes will be performed and it is expected that, with the increase in incubation time, their results will indicate that the new CNs proposed in this study can act as stimulators of life development with greater efficiency and, therefore, be a significant tool in the restoration of impacted areas.

BANKING MEMBERS:
Presidente - PATRICIA SUELI DE REZENDE
Externa à Instituição - FLÁVIA FIGUEIRA ABURJAILE - UFMG