EM - Escola de Minas

URI permanente desta comunidadehttp://www.hml.repositorio.ufop.br/handle/123456789/6

Notícias

A Escola de Minas de Ouro Preto foi fundada pelo cientista Claude Henri Gorceix e inaugurada em 12 de outubro de 1876.

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Filtros

2016 - 2019112020 - 202111

Configurações

Autor: search.filters.author.Galvão, Paulo Henrique FerreiraTem arquivos: Sim

Resultados da Pesquisa

Agora exibindo 1 - 10 de 22
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    Determining groundwater availability and aquifer recharge using GIS in a highly urbanized watershed.
    (2021) Conicelli, Bruno Pirilo; Hirata, Ricardo; Galvão, Paulo Henrique Ferreira; Luiz, Mariana Bernardino; Simonato, Mateus Delatim; Abreu, Marcio Costa; Aranda, Nataly; Terada, Rafael
    Extensive urbanized areas, characterized by waterproofed soils, increase runoff, which reduces the rainwater infiltration into the ground. However, water, sewer, and rainwater distribution systems leak, as there is excess irrigation in green areas, resulting in anthropic recharging in urban aquifers larger than in rural areas with equivalent climates. This scenario occurs in the Upper Tietˆe Watershed (UTW), an area of 5,868 km2 that drains the principal rivers of the Sao ̃ Paulo’s metropolitan region in Brazil, where groundwater plays a complementary role for domestic, industrial, and agricultural supplies, totalizing extraction rates higher than 11 m3 /s. In this paper, a Geographical Information System (GIS) was established to assess regional groundwater availabilities using adaptations of classic recharge methods such as soil water budget calculations and estimation of minimum sustainable river flow. For this, a surface runoff map, based on soil and slope terrain data, was evaluated using the information on water and sanitation infrastructure and meteorological data. We found that recharge in urban areas (with water and sewer mains) was 437 mm/yr and 106–407 mm/yr in rural areas. Considering the need to maintain a minimum historical flow of 20 m3 /s in the hydrographic basin of the Tietˆe River, the total exploitable groundwater is 33 m3 /s. The compilation of various GIS methods can help decision-makers develop alternative water security management plans in complex urbanized-regions such as in the metropolis of Sao ̃ Paulo.
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    Natural hydrogeochemical background levels in the carste Lagoa Santa protection unit, Minas Gerais, Brazil.
    (2021) Cardoso, Frederico Aragão; Velásquez, Leila Nunes Menegasse; Galvão, Paulo Henrique Ferreira; Vieira, Luísa Costa
    The identification of hydrogeochemical anomalies in karst water resources represents a crucial step in Brazil’s water management plans. Accelerated urban and industrial development occurs in the region that includes the Carste Lagoa Santa Protection Unit, State of Minas Gerais, which may negatively impact its water quality. This paper establishes Natural Background Levels (NBL) of waters collected from deep tubular wells and springs for Si4+, Ca2+, Mg2+, Na+, K+, HCO3 − , SO4 2 , Cl− to understand sources of possible geogenic and anthropogenic anomalies. Areas with surpassed thresholds were compared with geological, hydrogeochemical, and land use data. Every parameter, except for chloride, showed elevated concentrations due to lithologic origin. The NBLs for waters of wells and springs are, respectively, 17.9 and 12.7 mg/L (silica), 97.0 and 91.5 mg/L (calcium), 4.9 and 2.9 mg/L (magnesium), 6.2 and 3.8 mg/L (sodium), 1.0 and 0.3 mg/L (potassium), 285.5 and 254.6 mg/L (bicarbonate), 9.4 and 13.6 mg/L (sulfate). Chloride, analyzed only in groundwater, presented 6.7 mg/L indicating a possible influence of upstream urban areas of Lagoa Santa and Pedro Leopoldo municipalities. Volatile and Semivolatile Organic Compounds were also analyzed, but all of them were below the detection limit. This work is important to comprehend the NBL of major elements, reveal geogenic anomalies, and distinguish carbonate aquifer units from the impure ones.
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    Karst hydrogeological controls and anthropic effects in an urban lake.
    (2021) Alves, Michele Aparecida Gomes; Galvão, Paulo Henrique Ferreira; Aranha, Paulo Roberto Antunes
    Reduction in volume of surface water bodies can sometimes be associated with hydraulic connections to groundwater aquifers. This is often the case in karstic aquifers that are used for water supply. This paper analyzed possible karst hydrogeological controls and anthropic effects in the depletion of a 1 km2 lake in the municipality of Sete Lagoas, Minas Gerais, Brazil. Several techniques were used for the analyses: long-term pumping test coupled with stable isotopic samplings ( 18O and 2 H) to analyze for hydraulic connections and estimation of groundwater-lake water mixture proportion; geophysical surveys (electrical resistivity image, and vertical electrical sounding) for mapping subsurface discontinuities; potentiometric maps (static and dynamic levels) and urban-industrial expansion of well pumping rates; climatological water budget from 1961 to 2019 for climate variation analyzes; and a 3D-karst hydrogeological modeling. Results show climatic variation combined with urban-industrial expansion increases the demand for water in the region and directly impacts local potentiometric surfaces, and hence the lake water level. Geophysical surveys indicate that lake is karstically structured and identified preferential flowpaths for water infiltration and mixing. The pumping test shows a drawdown stabilization, from a transient-flow regime to a steady-state, indicating a hydraulic connection with a water source that isotopically is more evaporated (common in surface water), which contributes 13% to the mixture.
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    Determining groundwater availability and aquifer recharge using GIS in a highly urbanized watershed.
    (2020) Conicelli, Bruno Pirilo; Hirata, Ricardo; Galvão, Paulo Henrique Ferreira; Luiz, Mariana Bernardino; Simonato, Mateus Delatim; Abreu, Marcio Costa; Aranda, Nataly; Terada, Rafael
    Extensive urbanized areas, characterized by waterproofed soils, increase runoff, which reduces the rainwater infiltration into the ground. However, water, sewer, and rainwater distribution systems leak, as there is excess irrigation in green areas, resulting in anthropic recharging in urban aquifers larger than in rural areas with equivalent climates. This scenario occurs in the Upper Tietê Watershed (UTW), an area of 5,868 km2 that drains the principal rivers of the Sao ˜ Paulo’s metropolitan region in Brazil, where groundwater plays a complementary role for domestic, industrial, and agricultural supplies, totalizing extraction rates higher than 11 m3 /s. In this paper, a Geographical Information System (GIS) was established to assess regional groundwater availabilities using adaptations of classic recharge methods such as soil water budget calculations and estimation of minimum sustainable river flow. For this, a surface runoff map, based on soil and slope terrain data, was evaluated using the information on water and sanitation infrastructure and meteorological data. We found that recharge in urban areas (with water and sewer mains) was 437 mm/yr and 106–407 mm/yr in rural areas. Considering the need to maintain a minimum historical flow of 20 m3 /s in the hydrographic basin of the Tietê River, the total exploitable groundwater is 33 m3 /s. The compilation of various GIS methods can help decision-makers develop alternative water security management plans in complex urbanized-regions such as in the metropolis of São Paulo.
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    An approach to map karst groundwater potentiality in an urban area, Sete Lagoas, Brazil.
    (2020) Gomes, Rafael Magnabosco de Almeida; Galvão, Paulo Henrique Ferreira; Carvalho, Ana Maciel de
    Due to complex hydrogeological contexts, mapping groundwater potential zones in karst regions is a difficult task. This study was conducted on a karst terrain in Sete Lagoas, Brazil, where rapid urban growth without adequate water resources management resulted in the drilling of unproductive wells and possible aquifer over-exploitation due to the concentration of wells. The objective was to develop a method for mapping groundwater potentiality for karst aquifers, serving as water resources management tool, based on 3D geological modelling, field work and pumping test data, remote sensing, geophysics analysis and production of thematic maps, resulting in the hydrogeological conceptual model. The groundwater potentiality map showed that most potential zones are on the central area, limited by grabens, where limestones are in contact with unconsolidated sediments, on areas with higher density of morphostructural and geophysical lineaments, mainly in east–west and north–east directions, near karst surface features, on thicker karstified zones, with higher recharge rates.
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    Nitrate contamination in Brazilian urban aquifers : a tenacious problem.
    (2020) Hirata, Ricardo; Cagnon, Fabiana Alves; Bernice, Aline Michelle; Maldaner, Carlos Henrique; Galvão, Paulo Henrique Ferreira; Marques, Carlos Henrique Gil; Terada, Rafael; Varnier, Claudia Luciana; Ryan, M. Cathryn; Bertolo, Reginaldo Antonio
    This study follows the geochemistry of nitrogen in a Cretaceous and unconfined sedimentary aquifer in the city of Urânia (Brazil) over 20 years. Although the sewer network was built in the 1970s, the nitrate contamination problem (>45 mg/L-NO3 −) persists to this day. The oldest urbanization areas located in the north of the city initially used cesspits for wastewater and currently present the highest nitrate concentrations (>120 mg/L-NO3 −), with the plume reaching the deeper aquifer portions (up to 100 m). The contamination is not as dramatic in the south part of the city, where urbanization including installation of the sewage network with PVC pipes that are more resistant to leak than the old ceramic networks occurred after 1985. Based on the constructive well profiles, three hydrogeochemical zones were established: shallow (60 m), with 17 mg/L-NO3 −. The current total nitrate mass in the aquifer exceeds 731 kg-NO3 −. Numerical flow (Modflow) and transport (MT3D) model scenarios support the hypothesis that the nitrate contamination is caused by substantial infiltration of nitrogen through the cesspits until the 1970s, but after the 1990s, leaks from the sewer network should be responsible for the maintenance of the recently observed high concentrations of nitrate.
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    Influência do uso do solo na taxa de infiltração da água na bacia hidrográfica dos Igarapés 54 E 7, Paragominas/PA.
    (2020) Galvão, Paulo Henrique Ferreira
    A infiltração é o fenômeno em que a água penetra no perfil do solo devido a este meio ser permoporoso, ou por capilaridade em solos pouco permeáveis. Se a percolação for mais profunda, a água contribuirá com a recarga do aquífero local. A taxa de infiltração pode ser diferente a depender do tipo e do uso e ocupação do solo, da cobertura vegetal (ou ausência dela) ou do grau de compactação do terreno (natural ou antropicamente induzido). O município de Paragominas, sudoeste do Pará, possui locais em que a combinação de diferentes tipos de solo, cobertura vegetal, manejo e de manutenção da mata ciliar podem resultar em diferentes taxas de infiltração da água, afetando na recarga dos aquíferos locais. A pesquisa avaliou possíveis mudanças nas taxas de infiltração de água em áreas de mata ciliar, pastagem e agricultura no igarapé 54 e no igarapé 7 e as comparou com os períodos seco e chuvoso. Parâmetros como granulometrias e teores de umidade de cada solo foram igualmente avaliados. Constatou-se uma estreita relação entre taxa de infiltração, teor de umidade, textura e tipo de manejo do solo. Em mata ciliar, o caráter argiloso do terreno e o papel da vegetação foram determinantes no baixo valor de infiltração; em pastagem, houve valores distintos de infiltração entre a seca e a chuva devido à baixa capacidade de retenção de umidade na camada superficial do solo, além da compactação devido ao pisoteio do gado; na área de agricultura (apenas no igarapé 54) houve um comportamento próximo nas duas estações, com a taxa de infiltração estabilizando aos 60 minutos.
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    Recharge sources and hydraulic communication of karst aquifer, São Miguel watershed, MG, Brazil.
    (2020) Lucon, Thiago Nogueira; Costa, Adivane Terezinha; Galvão, Paulo Henrique Ferreira; Leite, Mariangela Garcia Praça; Madeira, Thiago José Augusto; Nogueira, Leonardo Brandão
    The main public water supply in the São Miguel watershed (MG, Brazil) comes from a well-developed karst region, where information about hydraulic communications between caves entrances, sinkholes, recharge and discharge areas are still unknown. The study aims to identify regional hydrogeological processes describing groundwater hydrochemical evolution, interactions between meteoric, surface and ground waters, recharge and discharge sources, and possible hydraulic communications for proper management of water resources. Geophysical data were analyzed and water samples (meteoric, surface, and groundwater) throughout the watershed were collected for stable isotopes (18O and 2 H) and major ions analyzes. Results indicated strong influences of regional geological structures in the karst water flow directions; high concentrations of major ions in the central region of the watershed are common; karstification processes and aquifer recharge are more active during the rainy season, while in the dry season the watershed is supplied by groundwater.
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    Cadmium behavior in a karst environment hydrological cycle.
    (2020) Lucon, Thiago Nogueira; Costa, Adivane Terezinha; Galvão, Paulo Henrique Ferreira; Leite, Mariangela Garcia Praça
    Karst regions are important water providers, supplying approximately 25% of the world population. These areas present higher vulnerability to contamination due to hydrodynamics, which hampers the natural depuration of these waters until reaching the underground environment. High concentrations of cadmium (Cd) are observed in the São Miguel watershed, state of Minas Gerais, Brazil. This toxic element is generally and predominantly released into the atmosphere by burning materials that have Cd in their composition, potentially contaminating surface and groundwater. Therefore, the objective of the study is to map Cd concentrations in the hydrological cycle of the São Miguel karst watershed and, through natural background level values (NBL 90%) of rainwater, surface water and groundwater, to understand the seasonal behavior of this element, and to identify the most vulnerable areas to contamination. To achieve this goal, rainwater, surface, and groundwater seasonal monitoring were conducted in 87 sampling stations. A total of 335 samples were collected, distributed over a watershed area of 520 km2 . Concentrations of cadmium above 1 μg/L were found in 21.49% of samples during the rainy season. The origin and distribution of Cd were related to rainfall. For rainwater samples, 90% presented Cd concentration of 3.06 μg/L. When these waters precipitate, they contaminate surface waters (NBL 90% = 1.50 μg/L) and groundwater (NBL 90% = 2.81 μg/L). This study presented a hydrochemical cycle map and proposed NBL values of Cd for surface water and groundwater, helping to understand how the environment is contaminated by this element.
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    Natural background levels and validation of the assessment of intrinsic vulnerability to the contamination in the Carste Lagoa Santa Protection Unit, Minas Gerais, Brazil.
    (2020) Cardoso, Frederico Aragão; Velásquez, Leila Nunes Menegasse; Galvão, Paulo Henrique Ferreira; Tayer, Thiaggo de Castro; Lucon, Thiago Nogueira; Azevedo, Úrsula Ruchkys de
    The contamination of karst aquifers by anthropogenic activities causes a major issue regarding environmental policies, since they present high sensitivity, influenced by unique features such as dolines, swallow holes, and conduits. This paper is focused on the Carste Lagoa Santa Protection Unit, MG, Brazil, and presents three main objectives: to determine the natural background levels of chloride, nitrate, sulfate, and phosphate; to indicate the locations where the concentrations of those parameters exceed the natural background levels in the existing vulnerability map and, finally, to determine the proportion of the areas (in percentage) where this surpassing occurs, according to the vulnerability classes (high, moderate and low). Results have shown values (90th percentile) of 2.4 mg/L, 1.0 mg/L, 5.3 mg/L, and 0.1 mg/L, for Cl−, NO3−, SO4−2, and PO4−3, respectively, indicating that for all four parameters, there were areas (mainly distributed within moderate vulnerability portions) where the values were surpassed, which suggests anthropogenic activity due to the presence of urban settlements and agricultural activities. Therefore, the proposal of natural background levels was essential to understand the hydrochemistry of the studied region.