Navegando por Assunto "Groundwater"

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Acesso aberto (Open Access)
Análise de intrusão salina e qualidade de água em aquífero costeiro na Vila de Algodoal (Ilha de Maiandeua, Pará)
(Universidade Federal do Pará, 2023-09-22) PEREIRA, Lucas Yan de Oliveira; KAWAKAMI, Silvia Keiko; http://lattes.cnpq.br/5306256489815710; https://orcid.org/0000-0002-0548-7976; RANIERI, Leilanhe Almeida; http://lattes.cnpq.br/3129401501809850; https://orcid.org/0000-0002-9870-4879
The increasing urbanization of coastal areas increases the demand for water resources and consequently leads to intensive exploitation of groundwater and anthropogenic impacts that result in groundwater quality degradation. The objective of this research was to assess potential saline intrusion and groundwater contamination in a marine protected area of sustainable use, Algodoal Village (Maiandeua, PA). For the first stage of the research, the quality of groundwater used for human consumption was evaluated based on current regulations (CONAMA Resolution 396/2008; Ministry of Health Ordinance 888/2021). Groundwater characterization was carried out using well water collected during rainy and less rainy periods (between 2021 and 2023), with in-situ physicochemical, microbiological, and major ion parameter analyses by chromatography. Topographic measurements and water table level measurements were also conducted. For the second stage, the results of a socio-environmental questionnaire applied to village residents were analyzed to ascertain their perception of water quality-related issues. Samples from the coastal aquifer presented average electrical conductivity (EC) values of 453 ± 1 µS/cm and total dissolved solids (TDS) of 225.8 ± 1 mg/L. The Cl⁻ ion showed an average concentration of 60 ± mg/L, with several wells exceeding the acceptable potability limit. Significant differences were observed for data collected in the first rainy period (March 2022), where EC averaged 290 µS/cm and TDS was 145 mg/L. The relationship between redox potential, ranging from 0.14 to 0.54 mV, and pH, ranging from 3.2 to 6.7, indicated a tendency toward a reducing acidic environment, typical of a subterranean transitional environment. All analyzed wells were contaminated with total and thermotolerant coliforms. Out of the 34 administered questionnaires, 52% indicated perception of some water quality problem, such as brackish water, for example. Poor water quality is locally associated with the process of saline intrusion and bacterial contamination due to proximity to septic tanks. The shallow depth of the wells (average of 12 m) exacerbates the poor groundwater quality in the village. It is concluded that the aquifer water is not recommended for human consumption, and saline intrusion occurs throughout the year, being more intense in the dry period.
Acesso aberto (Open Access)
Índices de qualidade das águas subterrâneas de abastecimento público da Ilha do Mosqueiro, município de Belém - PA
(Universidade Federal do Pará, 2015-02-09) LOPES, Raynner Menezes; SANTOS, Maria de Lourdes Souza; http://lattes.cnpq.br/1604134738302499
Acesso aberto (Open Access)
Recarga do aquífero livre na Universidade Federal do Pará, campus Belém
(Universidade Federal do Pará, 2023-02-06) SILVA, Salim Rodrigues da; PENNER, Giovanni Chaves; http://lattes.cnpq.br/3110276957027781
In Brazil urban supply, rural supply, industry, mining, thermoelectric, animal and irrigation consume approximately 61.46 billion m³/year of fresh water, with the greatest demand being urban supply (25%). In Belém, groundwater collection to feed the Water Supply System has been increasing. Despite this, the low quality of its distribution ends up stimulating the capitation of water without any criteria, contributing to the overexploitation of aquifers. In the field of scientific research, in the State of Pará, the amount of work to estimate underground recharge is incipient, making the development of new research urgent. Therefore, this work aims to estimate the recharge of the aquifer free of primary porosity located in an alluvial deposit, underlying the Federal University of Pará (UFPA), Belém campus. The recharge estimate was carried out using the Water-Table Fluctuation (WTF) method in 8 monitoring wells distributed in the so-called health and professional sectors of the Federal University of Pará. The mean water level variation in the study area was between 0.76 and 2.27 m (discrete and continuous monitoring). A specific yield (Sy) was determined through a pumping test, which provided data that were analyzed in the AQTESOLV Demo software, using the Tartakovsky-Neuman analytical solution. The Sy result of the pumping test was 0.1 (10%). The estimated recharge for discrete monitoring was between 101.40 mm and 371.60 mm (year 2020), between 75.50 mm and 552.60 mm (year 2021) and between 19.50 mm and 140.50 mm (year 2022), with an average of 583.51 mm, which represents 6.93% of the precipitation in the study period (8,419.14 mm) and for continuous monitoring, it was between 40.00 mm and 87.90 mm (year 2020) and between 19.30 mm and 218.80 mm (year 2021), with an average of 539.45 mm, which corresponds to 38.86% of the precipitation of the study period (1,338.10 mm). Thus, based on discrete and continuous monitoring data, the average recharge for the study area corresponds to approximately 22.89% of the total precipitation. The results referring to the correlation between water table fluctuation and rainfall showed an average determination coefficient of 22.49%. Both the recharge and the correlation proved to be consistent with the other surveys carried out in Brazil. As explained above, continuous assessment of aquifer recharge is recommended for the sustainable use of groundwater resources, in order to ensure their multiple uses.
Acesso aberto (Open Access)
Retenção do dimetoato e sua relação com pH e teores de argila e matéria orgânica nos sedimentos da zona não-saturada de uma microbacia no nordeste paraense
(Instituto Nacional de Pesquisas da Amazônia, 2007-06) LIMA, Lilianne Maia; SOUZA, Eliene Lopes de; FIGUEIREDO, Ricardo de Oliveira
On smallholder farms of eastern Amazonia, in particular the northeast of the Pará state, heavy by pesticide applications at industrial half-perennial crops are very common. Due to their large use, mainly the dimethoate, in the catchment of the Cumaru stream, Igarapé-Açu county, we evaluated the retention process of this compound in samples of the non saturated zone, as well as verified the effects of soil pH and clay and organic mater contents in this process. Among the main pesticides the farmers use in this region, dimethoate was selected for this study, due to its larger leaching potential according to the GUS (Groundwater Ubiquity Score) index. A sorption experiment was carried out to evaluate the retention of the dimethoate in sediments in the non saturated zone. The experiment showed that the sorption of the dimethoate varied from 2.5% to 36.2% (initial concentration of 20 mg.l-1) and from 6.2% to 31.0% (initial concentration of 10 mg.l-1). These data demonstrate a high contamination potential of the groundwater by this compound, mainly due to its high mobility and low retention capacity. The dimethoate sorption rates were positively related to organic matter content in the sediments. On the other hand, values have an inverse relationship with the sorption rates of dimethoate, while clay content did not produce any effect on its retention.