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1.
Sci Total Environ ; 946: 174494, 2024 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-38969111

RESUMEN

Gypsum plays a prominent role in agriculture, being considered an effective alternative to alleviate subsurface acidity due to its higher solubility and containing sulfur. However, another significant aspect is which pose long-term risks of groundwater contamination due to excessive applications of salts, pesticides, and other chemicals that will be leached, or even soil chemical depletion. So far, no study has focused on understanding the impacts of the atmospheric gypsum plume originating from gibbsite mining and processing on the leaching of soil bases and chemical degradation surrounding these sites. In this study, we evaluated the behavior of chemical characteristics in soil profiles distributed along the dispersion of the atmospheric plume and in areas without interference from the industrial sector in the state of Maranhão, Northeast Brazil. Fifty-three sampling points were collected at 7 locations based on the dispersion of the dust plume through wind drift. Each sampling point was represented by three composite soil samples at depths of 0.0-0.20, 0.40-0.60, and 1.00-1.20 m, where the chemical soil characteristics were evaluated. The average levels of Ca, Mg, and K in the studied layers are classified as low, with minimum values below the method's detection limit, and they also show imbalance due to higher concentrations of Ca in the surface layer in areas affected by atmospheric dispersion. The sum and saturation of bases at all depths are classified as low. Higher aluminum saturation values were observed in the deeper soil layers. The gypsum dust altered the soil's chemical characteristics at the evaluated depths; therefore, it is necessary to seek means to mitigate gypsum dust release during gibbsite extraction and processing and ensure that the soils in areas near these enterprises maintain their natural characteristics.

4.
Appl Biochem Biotechnol ; 194(2): 694-708, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34506005

RESUMEN

This study aimed to investigate the phytoremediation potential promoted by Baccharis dracunculifolia DC. and Baccharis trimera (Less.) DC. in copper mining tailing area, in the Southern part of Brazil. The plants were selected considering their spontaneous growth in tailing area. The phytoremediation indexes including translocation factor (TF), bioconcentration factor (BCF), metal extraction ratio (MER), and plant effective number (PEN) were assessed. Both species showed higher concentrations of heavy metals in the roots than to the shoots. B. trimera has potential for phytoextraction of Zn, Cd, Cr, and Pb and phytostabilization of Ba and Ni, whereas B. dracunculifolia demonstrated potential for phytoextraction of Pb and phytostabilization of Cu, Zn, and Ba. B. trimera showed higher potential in phytoremediation of the metals such as Cu > Zn > Cr > Ni and Cd than the B. dracunculifolia plants. A smaller number B. trimera plants was required to remove 1 g of Cu, Zn, Cr, Pb, Ni, and Cd than B. dracunculifolia plants, and implies that B. trimera is more efficient for decontamination of the metals. Both species showed potential for phytoremediation of metals in the mining tailing area under study.


Asunto(s)
Biodegradación Ambiental
5.
J Cosmet Dermatol ; 21(2): 827-835, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33834606

RESUMEN

BACKGROUND: There is currently a great interest not only in developing products for the protection and recovery of chemically damaged hair, but also in developing effective protocols to investigate the impact of chemical treatments and attest the efficacy of innovative hair care products. Among the most relevant cosmetic treatments for hair are bleaching and coloring, which have been shown to significantly impair mechanical and structural properties. OBJECTIVES: This study aimed to characterize the damage induced by hair bleaching and coloring and to evaluate the protective effects of a hair care treatment based on integral silk proteins (fibroin and sericin) and vegetable-derived polysaccharides from linseed (Linum usitatissimum L.). METHODS: Hair swatches were subjected to different treatment protocols in order to evaluate the protective effect of proposed and benchmark products during bleaching and coloring processes. Tensile tests were performed to assess mechanical properties and improvement in resistance to breakage. Goniophotometric measurements were applied to determine improvement in luster. Hair fiber surface and relief were evaluated by SEM image analysis. RESULTS: Swatches bleached and treated with both evaluated products had a significant increase in resistance and reduced structural damage. Swatches colored and treated with both evaluated products showed reduced structural damage, and a significant increase in resistance and luster after the 1st and 5th washes. CONCLUSIONS: The proposed product was effective in protecting and repairing bleached and colored swatches, improving resistance and luster and reducing structural damage. By applying complementary techniques within a reliable evaluation protocol, it was possible to attest the protective properties of the product under study.


Asunto(s)
Cosméticos , Preparaciones para el Cabello , Cabello , Humanos , Polisacáridos/uso terapéutico , Proteínas
6.
Int J Phytoremediation ; 24(1): 59-65, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34033721

RESUMEN

Urban rivers are intensely impacted by pollution with metals resulting from anthropogenic activities, and these elements present in water and sediments can be ecofriendly phytoremediated. This study aimed to evaluate the levels of metals in the sediments and colonizing plants growing in point bars in the channeled bed of the Dilúvio Stream, Southern Brazil. Sediment and plants were sampled at five-point bars with consolidated vegetation. These point bars are formed mainly by sand, with increasing concentrations of clay plus silt, carbon, nitrogen, and metals (Zn, Cu, Cr, Ni, Pb, and Cd) downstream. The concentration of Zn (338 µg/g) and Cu (219 µg/g) in sediments were 1.6 and 1.11 above the probable effect level at the most downstream site. The translocation factor was low in all sites and for all potentially toxic metals evaluated (ranging from 0.01 to 0.63). However, bioaccumulation factor exhibited high values, especially for Cd (average of 2.51), Ni (1.62), Zn (1.49), and Cr (1.25), suggesting that the colonizing plants have more potential for phytostabilization and phytoaccumulation than phytoextraction. These plants can be considered as natural filtering reducing the environmental contamination and the flow of these contaminants in the drainage network. Statement of novelty: Colonizing plants growing in point bars of urban rivers are common around the world; however, their phytoremediation potential is poorly studied. Colonizing plants may be useful for phytoremediation of water, effluents, and sediments of the Dilúvio Stream (Southern Brazil), polluted by potentially toxic metals that originated from the urbanization.


Asunto(s)
Metales Pesados , Contaminantes Químicos del Agua , Efectos Antropogénicos , Biodegradación Ambiental , Brasil , Monitoreo del Ambiente , Sedimentos Geológicos , Metales Pesados/análisis , Contaminantes Químicos del Agua/análisis
7.
Ciênc. rural (Online) ; 52(11): e20210259, 2022. graf
Artículo en Inglés | VETINDEX | ID: biblio-1375136

RESUMEN

The animal production system has been affected in the Rio Grande do Sul State by low maize production, mainly non-ruminants. The total demand is not well known and official data are inaccurate and underestimated. This research characterized and analyzed the maize grain demand and supply for animal feed in the last 15 years at the Rio Grande do Sul State. The state supply was obtained from governmental harvests measurement. The demand was obtained by the total animals (swine, poultry and dairy and beef cattle), while the total state demand was obtained using the relative national consumption from these segments in relation to the total. The current maize grain demand was at the order of 6 million tons for the feeding of swine, poultry and cattle, while total demand was between 9 to 12 million tons in the Rio Grande do Sul State. The state maize production supplied near half of the total demand for the animal protein chain, characterizing a significant deficit for this sector, providing instability and making this productive chain economically unfeasible in the state.


Os sistemas de produção animal tem sido severamente afetada no estado do Rio Grande do Sul pela baixa oferta de milho produzido a nível estadual, especialmente não-ruminantes. A demanda do setor não é conhecida e as estimativas oficiais são imprecisas e subestimadas. Assim, o objetivo deste trabalho foi caracterizar e analisar a demanda e a oferta do milho produzido no estado para a alimentação animal nos últimos 15 anos. A oferta estadual foi obtida pelo acompanhamento governamental das safras. A demanda por segmento (aves, suínos e bovino de leite e corte) foi obtida pelo tamanho do rebanho gaúcho, enquanto que a demanda total foi utilizando a mesma proporção do consumo nacional de milho em relação aos segmentos avaliados. A demanda atual de milho para a alimentação de suínos, aves e bovinos no Rio Grande do Sul é da ordem de 6 milhões de toneladas e a demanda total do estado situa-se entre 9 a 12 milhões de toneladas. A oferta estadual de milho supre pouco mais da metade da necessidade para a cadeia da proteína animal, caracterizando um déficit significativo para este setor, proporcionando instabilidade e inviabilizando economicamente esta cadeia produtiva no estado, uma vez que há alta demanda de importação de milho de outros estados.


Asunto(s)
Zea mays , Producción de Cultivos/estadística & datos numéricos , Alimentación Animal/provisión & distribución , Brasil
8.
Acta Ortop Bras ; 29(4): 228-231, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34566484

RESUMEN

Femoral Shaft intramedullary nails were first described by the Aztecs in 16th century, but the modern use of intramedullary nails as the gold standard treatment for femoral shaft fractures began with Gerald Kuntcher in 1939. From the first Kuntcher's study in 1939, to the creation of interlocking nail, a long and some minor developments were described around the world. However, a major development is missing: the first nail to have a rotational and vertical stability locking system was described by Flavio Godoy Moreira, but was never published on an indexed journal for the correct historical reference. Level of Evidence V, Therapeutics Studies, Expert Opinion.


A história da haste intramedular bloqueada nas fraturas do fêmur se inicia com os Astecas no século 16, mas o uso moderno que a tornou o padrão ouro no tratamento destas fraturas se inicia com Gerald Kuntcher em 1939. Do estudo inicial de Kutcher até o desenvolvimento da haste bloqueada muitos pequenos desenvolvimentos foram descritos ao redor do mundo. Dentro deste desenvolvimento, a primeira haste a ter um controle vertical e rotacional foi descrito por Flavio Pires de Camargo, e nunca foi publicado em um jornal indexado que permita sua correta referência histórica. Nível de Evidência V, Estudos Terapêuticos, Opinião de especialista.

9.
Acta ortop. bras ; Acta ortop. bras;29(4): 228-231, Aug. 2021. graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1339051

RESUMEN

ABSTRACT Femoral Shaft intramedullary nails were first described by the Aztecs in 16th century, but the modern use of intramedullary nails as the gold standard treatment for femoral shaft fractures began with Gerald Kuntcher in 1939. From the first Kuntcher's study in 1939, to the creation of interlocking nail, a long and some minor developments were described around the world. However, a major development is missing: the first nail to have a rotational and vertical stability locking system was described by Flavio Godoy Moreira, but was never published on an indexed journal for the correct historical reference. Level of Evidence V, Therapeutics Studies, Expert Opinion.


RESUMO A história da haste intramedular bloqueada nas fraturas do fêmur se inicia com os Astecas no século 16, mas o uso moderno que a tornou o padrão ouro no tratamento destas fraturas se inicia com Gerald Kuntcher em 1939. Do estudo inicial de Kutcher até o desenvolvimento da haste bloqueada muitos pequenos desenvolvimentos foram descritos ao redor do mundo. Dentro deste desenvolvimento, a primeira haste a ter um controle vertical e rotacional foi descrito por Flavio Pires de Camargo, e nunca foi publicado em um jornal indexado que permita sua correta referência histórica. Nível de Evidência V, Estudos Terapêuticos, Opinião de especialista.

10.
J Cosmet Dermatol ; 20(7): 2190-2202, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33169920

RESUMEN

BACKGROUND: The use of the injectable products for soft tissue augmentation and treatment of skin aging is an uncomfortable, invasive and related to several complications, and chronic reactions, mainly after long-term application. Efforts to develop new topically active anti-aging products with fewer adverse effects are a huge challenge that should be faced. AIMS: We evaluated the anti-aging effects of a phytocosmetic preparation containing Thymus vulgaris associated with lecithin (ThymLec) on the facial wrinkles, expression lines, and face oval remodeling using a double-blind placebo-controlled clinical trial and in vitro cell culture assays. METHODS: A clinical trial was conducted to evaluate the effects of ThymLec 2% on the area, length, and depth of the perioral and crow's feet wrinkles, nasolabial and smile lines, as well as face oval remodeling in female volunteers using a sophisticated Bio3D Structured-light Scanner. In the in vitro studies using 3T3-L1 mouse embryonic fibroblasts, adiponectin was measured by immunoenzymatic assay, adipogenesis by the AdipoRed reagent method, and the PPAR-γ expression by RT-PCR analysis. RESULTS: Topical treatment with ThymLec 2% reduced facial wrinkles and expression lines promoting a face oval remodeling. In the in vitro studies, ThymLec upregulated the PPAR-γ expression increasing adiponectin production and stimulating the adipogenesis process. CONCLUSIONS: The phytocosmetic preparation containing Thymus vulgaris and lecithin is an innovative and safe topical anti-aging product promoting fat tissue augmentation by adipogenesis stimulation via the upregulation of PPAR-γ expression and adiponectin production.


Asunto(s)
Envejecimiento de la Piel , Thymus (Planta) , Adipogénesis , Animales , Factores de Transcripción con Cremalleras de Leucina de Carácter Básico , Método Doble Ciego , Femenino , Fibroblastos , Ratones
11.
Forensic Sci Int ; 315: 110459, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32853973

RESUMEN

The Marihuana Polygon production of Cannabis sativa L. supplies the northeastern region of Brazil and represents 30% of the nation's market. The international trend of indoor cultivation is also occurring in Brazil, and the Brazilian Federal Police (BFP) has been increasing its apprehension of cannabis seeds sent by mail. The present work aims to assess the utility of the multi-element composition of different cannabis plant parts and soil samples where the plants were cultivated to determine their geographic origin. Statistical tools were applied to classification of marijuana samples from distinct geographic regions within northeastern Brazil, including indoor cultivated samples. The multi-element quantification was determined using inductively-coupled plasma - optical emission spectrometry (ICP-OES), and the data were compared by the Kruskal-Wallis H test, and subsequently, multiple discriminant analysis (MDA). The results of the multi-element concentration of cannabis plant samples were also subjected to a principal component analysis (PCA) and an orthogonal partial least squares discriminant analysis (OPLS-DA). The cannabis plant samples from the Marihuana Polygon could be clearly separated from those cultivated indoors, and the distance between them was detectable. The MDA revealed that phosphorus, calcium, magnesium, selenium, and arsenic concentrations were used as variables for this separation. Our results demonstrate that multi-element composition analysis can be used to indicate the origin or cultivation location of cannabis plants. Routine laboratory analyses consisting of multi-element composition combined with statistical analyses provide a reliable tool by which C. sativa movement, cultivation, and interdiction efforts in Brazil may be assessed.


Asunto(s)
Cannabis/química , Tráfico de Drogas , Arsénico/análisis , Brasil , Calcio/análisis , Análisis Discriminante , Humanos , Magnesio/análisis , Fósforo/análisis , Análisis de Componente Principal , Selenio/análisis , Análisis Espectral/métodos
12.
Int J Legal Med ; 134(5): 1603-1612, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32583082

RESUMEN

According to the Brazilian Federal Police (BFP), the Brazilian Cannabis sativa illicit market is mainly supplied by drugs originated from Paraguay and Northeastern Brazil (Marijuana Polygon region). These two known routes, the increasing indoor cultivations (supported by online market), and drugs from Uruguay are also in BFP's sight. Forensic tools to aid police intelligence were published in the past years. In genetics, microsatellites have gained attention due to their individualization capability. This study aims to evaluate the effectiveness and efficiency of two STR multiplex systems previously proposed in 94 Cannabis sativa samples seized in Brazil. Principal coordinate analyses (PCoA), forensic parameters, and genetic structure analysis were executed. Both panels were effective in individualizing and origin discriminating all samples, and the system proposed in 2015 demonstrated better results. For this marker set, the probability of identity for a random individual is approximately one in 65 billion; also, the PCoA shows a clear genetic distinction among samples according to its origin. Bayesian inference populational structure analysis indicated a significant genetic diversity among seizure groups, matching with its origin. Overall, the STR multiplex systems were able to achieve its purpose in individualizing and differentiating, according to geographic region, Brazilian Cannabis sp. samples.


Asunto(s)
Cannabis/genética , Sitios Genéticos , Genotipo , Repeticiones de Microsatélite , Reacción en Cadena de la Polimerasa Multiplex , Brasil , Tráfico de Drogas/prevención & control , Genética Forense , Estructuras Genéticas , Humanos , Aplicación de la Ley/métodos , Análisis de Componente Principal
13.
Ci. Rural ; 50(6): e20190831, May 11, 2020. graf
Artículo en Inglés | VETINDEX | ID: vti-29107

RESUMEN

The lowland soils are characterized by high susceptibility to water saturation. This anaerobic condition is usually reported in paddy fields and alters the decomposition process of soil organic compounds. The aim of this study was to evaluate the soil microbial and enzymatic activity of a lowland soil at different soil moisture contents. A poorly drained Albaqualf cultivated with irrigated rice was used to evaluate microbial and enzymatic activity in treatments with different levels of soil moisture, being: i) 60% of field capacity (FC) (60%FC); ii) 100% of FC (100%FC); iii) flooded soil with a 2 cm water layer above soil surface, and iv) soil kept at 60%FC with late flood after 29 days the incubation. The greater soil microbial activity was observed in the 100%FC treatment, being 41% greater than 60%FC treatment and only 2% higher than flooded treatment. The enzymatic activity data by fluorescein diacetate (FDA) hydrolysis corroborated the higher CO2 release in treatments with higher soil moisture content. Differently from the results reported, the main methodologies to evaluate microbial activity still recommend maintenance of the soil with a moisture content close to 60% of the FC. However, in lowland soil with history of frequent paddy fields, the maintenance of moisture close to 60% of the FC can limit the microbial activity. The soil respiration technique can be used to evaluate the microbial activity in flooded soil conditions. However, further studies should be conducted to understand the effect of the cultivation history on the microbial community of these environments.(AU)


Os solos de várzea são caracterizados pela alta suscetibilidade à saturação por água. Esta condição anaeróbica é geralmente encontrada em solos arrozeiros e altera o processo de decomposição dos compostos orgânicos do solo. O objetivo deste estudo foi avaliar a atividade microbiana e enzimática de um solo de várzea sob diferentes teores de umidade no solo. Um Planossolo historicamente cultivado com arroz irrigado foi utilizado para avaliar a atividade microbiana e enzimática em tratamentos com diferentes níveis de umidade do solo, sendo: i) 60% de capacidade de campo (CC) (60%CC); ii) 100% da CC (100%CC); iii) solo inundado com uma camada de água de 2 cm acima da superfície do solo; e iv) solo mantido a 60%CC com inundação após 29 dias da incubação. A maior atividade microbiana do solo foi observada no tratamento 100%CC, sendo 41% maior que o tratamento 60%CC e 2% maior que tratamento inundado. Os dados da atividade enzimática pela hidrólise do diacetato de fluoresceína (FDA) corroboraram a maior liberação de CO2 nos tratamentos com maior umidade do solo. Diferentemente dos resultados encontrados, as principais metodologias para avaliação da atividade microbiana ainda recomendam manter o solo com umidade próxima a 60% da CC. No entanto, em solos de várzea com históricos de cultivos de arroz, a manutenção de umidade próxima a 60% da CC pode limitar a atividade microbiana. A técnica de respiração do solo pode ser usada para avaliar a atividade microbiana em condições de solo inundado. No entanto, mais estudos devem ser realizados para entender o efeito do histórico de cultivo na comunidade microbiana nesses ambientes.(AU)


Asunto(s)
Oryza/microbiología , Humedad del Suelo , Microbiología del Suelo
14.
Int J Phytoremediation ; 22(12): 1216-1223, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32297807

RESUMEN

The aim of this study was to investigate the phytoremediation potential promoted by Enydra anagallis at anthropogenic polluted area - Santa Bárbara Stream, south Brazil. The watercourse was selected considering it is the main source of water to Pelotas city and the presence of high levels of nutrients and toxic metals. The phytoremediation indexes as bioconcentration factor (BCF), translocation factor (TF), and plant effective number (PEN) were estimated. The results highlighted the possibility of application of E. anagallis in phytoextraction of Ca, K, Mg and P, showing the ability of maintaining high levels of elements in aerial parts of the plant. It was also detected the rhizofiltration mechanism (BCF > 1.0 and TF < 1.0), with possible application for the removal of aluminum, arsenic, chromium, copper, iron, manganese, sodium, nickel, lead, sulfur, vanadium and zinc. Regarding the Plant Effective Number (PEN), it can be highlighted the values found for Al (55 plants), P (38 plants) and S (56 plants), being the number of plants needed for removal of 1 g. Thus, E. anagallis showed natural potential for removing contaminants from the aquatic environment and along with further studies, it could be a good recovery alternative for other contaminated watercourses.


Asunto(s)
Arsénico/análisis , Metales Pesados/análisis , Contaminantes del Suelo/análisis , Anagallis , Biodegradación Ambiental , Brasil
15.
J Environ Manage ; 256: 109953, 2020 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-31989980

RESUMEN

The study evaluated plants with phytoremediation potential that occur spontaneously in an area of copper mining tailings in Southern of Brazil. Eleven plant species were investigated for heavy metal concentrations in its biomass. All species showed copper concentrations greater than 100 mg kg-1, and seven species highlighted for copper concentrations between 321 and 586 mg kg-1 and these species showed Cr concentrations between 25 and 440 mg kg-1. The species S. viarum Dunal and B. trimera Less were highlighted showing the highest concentrations of Cr (586 mg kg-1) and Cu (440 mg kg-1), respectively. Seven species showed Pb phytoextraction potential and four species showed Cu phytostabilization potential. It was concluded that the investigated species are adapted to low nutritional conditions and showed tolerance to heavy metals, mainly Cu, Pb and Cr in its biomass.


Asunto(s)
Metales Pesados , Contaminantes del Suelo , Biodegradación Ambiental , Brasil , Cobre , Minería , Raíces de Plantas
16.
J Forensic Sci ; 65(1): 259-265, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31411746

RESUMEN

DNA is one of the fastest growing tools in forensic sciences, increasing reliability in forensic reports and judgments. The use of DNA has increased in different areas of the forensic sciences, such as investigation of plant species, where plastid DNA has been used to elucidate and generate evidence in cases of traceability of genetically modified and controlled plants. Even with several advances and the practice of using DNA in forensic investigations, there are just few studies related to the identification of genetic tools for the characterization of drug and nondrug-types of Cannabis. Herein, the whole plastomes of two drug-type Cannabis are presented and have their structures compared with other Cannabis plastomes deposited in the GenBank, focusing in the forensic use of plastome sequences. The plastomes of Cannabis sativa "Brazuka" and of the hybrid Cannabis AK Royal Automatic presented general structure that does not differs from the reported for other C. sativa cultivars. A phylogenomic analyses grouped C. sativa "Brazuka" with the nondrug C. sativa cultivars, while the hybrid Cannabis AK Royal Automatic placed isolated, basal to this group. This suggests that the analysis of plastomes is useful toward genetic identification of hybrids in relation to C. sativa.


Asunto(s)
Cannabis/genética , Genoma de Plastidios , Plastidios/genética , ADN de Plantas , Bases de Datos de Ácidos Nucleicos , Ciencias Forenses , Secuenciación de Nucleótidos de Alto Rendimiento , Filogenia , Análisis de Secuencia de ADN
17.
Ciênc. rural (Online) ; 50(6): e20190831, 2020. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1133261

RESUMEN

ABSTRACT: The lowland soils are characterized by high susceptibility to water saturation. This anaerobic condition is usually reported in paddy fields and alters the decomposition process of soil organic compounds. The aim of this study was to evaluate the soil microbial and enzymatic activity of a lowland soil at different soil moisture contents. A poorly drained Albaqualf cultivated with irrigated rice was used to evaluate microbial and enzymatic activity in treatments with different levels of soil moisture, being: i) 60% of field capacity (FC) (60%FC); ii) 100% of FC (100%FC); iii) flooded soil with a 2 cm water layer above soil surface, and iv) soil kept at 60%FC with late flood after 29 days the incubation. The greater soil microbial activity was observed in the 100%FC treatment, being 41% greater than 60%FC treatment and only 2% higher than flooded treatment. The enzymatic activity data by fluorescein diacetate (FDA) hydrolysis corroborated the higher CO2 release in treatments with higher soil moisture content. Differently from the results reported, the main methodologies to evaluate microbial activity still recommend maintenance of the soil with a moisture content close to 60% of the FC. However, in lowland soil with history of frequent paddy fields, the maintenance of moisture close to 60% of the FC can limit the microbial activity. The soil respiration technique can be used to evaluate the microbial activity in flooded soil conditions. However, further studies should be conducted to understand the effect of the cultivation history on the microbial community of these environments.


RESUMO: Os solos de várzea são caracterizados pela alta suscetibilidade à saturação por água. Esta condição anaeróbica é geralmente encontrada em solos arrozeiros e altera o processo de decomposição dos compostos orgânicos do solo. O objetivo deste estudo foi avaliar a atividade microbiana e enzimática de um solo de várzea sob diferentes teores de umidade no solo. Um Planossolo historicamente cultivado com arroz irrigado foi utilizado para avaliar a atividade microbiana e enzimática em tratamentos com diferentes níveis de umidade do solo, sendo: i) 60% de capacidade de campo (CC) (60%CC); ii) 100% da CC (100%CC); iii) solo inundado com uma camada de água de 2 cm acima da superfície do solo; e iv) solo mantido a 60%CC com inundação após 29 dias da incubação. A maior atividade microbiana do solo foi observada no tratamento 100%CC, sendo 41% maior que o tratamento 60%CC e 2% maior que tratamento inundado. Os dados da atividade enzimática pela hidrólise do diacetato de fluoresceína (FDA) corroboraram a maior liberação de CO2 nos tratamentos com maior umidade do solo. Diferentemente dos resultados encontrados, as principais metodologias para avaliação da atividade microbiana ainda recomendam manter o solo com umidade próxima a 60% da CC. No entanto, em solos de várzea com históricos de cultivos de arroz, a manutenção de umidade próxima a 60% da CC pode limitar a atividade microbiana. A técnica de respiração do solo pode ser usada para avaliar a atividade microbiana em condições de solo inundado. No entanto, mais estudos devem ser realizados para entender o efeito do histórico de cultivo na comunidade microbiana nesses ambientes.

18.
Eng. sanit. ambient ; Eng. sanit. ambient;24(6): 1095-1102, nov.-dez. 2019. tab
Artículo en Portugués | LILACS-Express | LILACS | ID: biblio-1056115

RESUMEN

RESUMO A produção de resíduos tem aumentado em proporção direta com a industrialização dos países. Sendo assim, a disposição adequada desses resíduos é uma questão largamente discutida entre os órgãos ambientais. Por isso, o objetivo deste trabalho foi estudar o efeito residual de adições sucessivas de resíduos de curtume e da mineração de carvão sobre as propriedades químicas do solo e o acúmulo de cromo (Cr) em mamoneira. Os tratamentos aplicados em condições de campo foram: T1 - controle, ou seja, solo sem adubação; T2 - solo adubado com nitrogênio-fósforo-potássio (NPK) + calcário para atingir pH 6,0; T3 - solo misturado com lodo de curtume em dose adequada para se atingir pH 6,0 + PK; T4 - solo receptor de duas vezes a dose de lodo de curtume utilizada no T3 + PK; T5 - solo misturado com resíduo carbonífero + NPK + calcário em quantidade adequada para atingir pH 6,0; T6 - solo misturado com resíduo carbonífero + lodo de curtume em dose adequada para atingir pH 6,0 + PK; T7 - solo misturado com serragem cromada + NPK + calcário em quantidade adequada para atingir pH 6,0; T8 - solo misturado com Cr mineral + lodo de curtume em dose adequada para se atingir pH 6,0 + PK. Em campo, o solo recebeu os diferentes tratamentos. Posteriormente, amostras desse solo foram acondicionadas em vasos e o experimento com as plantas foi conduzido em delineamento inteiramente ao acaso, com três repetições por tratamento. O rendimento de matéria seca mostrou que a aplicação de serragem cromada (T7) proporcionou o maior crescimento da mamoneira, bem como os maiores teores de P no seu tecido. Os teores de Cr na parte aérea das plantas não atingiram níveis que podem ser considerados de contaminação desses vegetais. A distribuição desse elemento nas diferentes partes das plantas de mamoneira demonstrou a possibilidade de utilização futura dos grãos para produção de biodiesel.


ABSTRACT The production of waste has been increasing in direct proportion to the industrialization of the countries. Therefore, the adequate disposal of these wastes is an issue widely discussed among environmental agencies. Thus, the aim of this work was to study the residual effect of successive additions of tannery and coal mining waste on the chemical properties of the soil and the accumulation of chromium in castor bean plants. The treatments applied under field conditions were: T1 - control, that is, soil without fertilization; T2- soil fertilized with nitrogen-phosphorus-potassium (NPK) + limestone to reach pH 6.0; T3 - soil mixed with tannery sludge at a dose adequate to reach pH 6.0 + PK; T4 - soil receptor of twice the dose of tannery sludge used in treatment 3 + PK; T5 - soil mixed with coal residue + NPK + limestone in an amount adequate to reach pH 6.0; T6 - soil mixed with coal residue + tannery slurry at a dose adequate to reach pH 6.0 + PK; T7 - soil mixed with chrome sawdust + NPK + limestone in adequate quantity to reach pH 6.0; T8 - soil mixed with mineral Cr + tannery sludge at a dose adequate to reach pH 6.0 + PK. In the field, the soil received the different treatments. Subsequently, samples of this soil were conditioned in pots and the experiment with the plants was conducted in a completely randomized design, with three replicates per treatment. Subsequently, samples of this soil were placed in pots and the experiment with plants was conducted in a completely randomized design, with three replications per treatment. The dry matter yield showed that the application of chrome sawdust (T7) provided the highest growth of the castor bean, as well as the higher levels of P in its tissue. Chromium content in the aerial part of the plants did not reach levels that can be considered as contamination of these plants. The distribution of chromium in the different parts of the castor bean plants demonstrated the possibility of future use of the grains to produce biodiesel.

19.
Environ Sci Pollut Res Int ; 26(23): 24132-24142, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31228062

RESUMEN

Mining tailing areas may contain metal minerals such as Cu, Pb, Zn, Cr, and Cd at high concentrations and low nutrients for the growth of plants. This kind of conditions of the area, as well as lack of tailing structure, may limit the development of plants on these areas. Thus, the present study determined the metal, macronutrient, and micronutrient concentrations in the tissues of the roots and shoots of the Solanum viarum Dunal species as well as it evaluated the potential use of the plant for phytoremediation of mining tailing areas contaminated with heavy metals. The macronutrients, micronutrients, and heavy metals in the roots and shoots were determined by the digestion method with nitric and perchloric acid (HNO3-HClO4) and quantified by the ICP-OES. In S. viarum, the average concentrations of the metals presented in the dry biomass varied between the shoots and roots, being higher in the roots for metals such as Cu (229 mg kg-1), Zn (232 mg kg-1), Mn (251 mg kg-1), Cr (382 mg kg-1), Ni (178 mg kg-1), Pb (33 mg kg-1), and Ba (1123 mg kg-1). S. viarum indicates the possibility of a potential application in phytoremediation and treatment of areas contaminated with heavy metals.


Asunto(s)
Restauración y Remediación Ambiental/métodos , Metales Pesados/análisis , Minería , Contaminantes del Suelo/análisis , Solanum/química , Biodegradación Ambiental , Biomasa , Brasil , Metales Pesados/farmacocinética , Raíces de Plantas/química , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/metabolismo , Brotes de la Planta/química , Brotes de la Planta/efectos de los fármacos , Brotes de la Planta/metabolismo , Contaminantes del Suelo/farmacocinética , Solanum/efectos de los fármacos , Solanum/metabolismo , Distribución Tisular
20.
Int J Phytoremediation ; 21(11): 1145-1152, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31088309

RESUMEN

The evaluation of plants occurring naturally at contaminated environments are essential for applying this species in remediation techniques. In this context, the Sagittaria montevidensis with potential for phytoremediation was studied at an anthropogenic polluted stream in southern Brazil. The nutrients and heavy metal content were determined in the phytomass. The phytoremediation indexes were evaluated such as bioconcentration factor (BCF), translocation factor (TF), plant effective number (PEN), and potential phytoremoval (mg m-2). The S. montevidensis was then detected as presenting natural phytoextraction ability for potassium and calcium elements and also demonstrated rhizofiltration potential for phosphorus, manganese, aluminum, vanadium, sulfur, iron, arsenic, copper, magnesium, zinc, sodium, lead, cadmium, nickel, chromium, considering its ability of bioaccumulating these contaminants and retain high levels in the roots. The highest potential for bioremoval (mg m-2) of the S. montevidensis was detected for potassium and calcium (recommending thus the use for phytoextraction) and for aluminum, phosphorus, iron, magnesium, sulfur, and sodium, along with heavy metals (recommended for rhizofiltration). The S. montevidensis decontamination ability, along with its biomass production and its adaptability represents a great advance in order to the recovery of this degraded area and possible application in other contaminated watercourses in Brazil.


Asunto(s)
Metales Pesados , Sagittaria , Contaminantes del Suelo , Biodegradación Ambiental , Brasil , Nutrientes
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