|
|
|
| Registros recuperados: 18 | |
|
|
| Moreira,Cindy Silva; Alleoni,Luís Reynaldo Ferracciú. |
| The adsorption of heavy metals in soils affects their behavior in the environment and their bioavailability to plants. The knowledge of the adsorption mechanisms in competitive systems allows a more realistic evaluation of the metals' behavior in the soil than the single metal adsorption. The objectives of this study were (i) to evaluate Cd, Cu, Ni, and Zn adsorption in 14 surface samples (0-0.2 m) of representative soils of the Brazilian humid-tropical region, in competitive and non-competitive systems, and (ii) to establish metal affinity sequences for each soil, based in the maximum adsorption capacity (MAC) estimated by the Langmuir model. The Rhodic Eutrudox, the Kandiudalf Eutrudox, the Arenic Hapludalf, the Arenic Hapludult and the Typic Argiudoll... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Heavy metals; Competition; Tropical soil. |
| Ano: 2010 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162010000300008 |
| |
|
|
| Mendes,Kassio Ferreira; Alonso,Felipe Gimenes; Mertens,Tatiane Beatriz; Inoue,Miriam; Oliveira,Marcelo Gomes de; Tornisielo,Valdemar Luiz. |
| ABSTRACT The application of sewage sludge (SS) in agriculture is a practice used worldwide, and it is commonly applied in sugarcane to supply nutrients, with beneficial effects on crop productivity and soil; but SS can increase sorption and decrease desorption of herbicides. However, in tropical soils such as in Brazil, there are no studies regarding the behavior of pre-emergent herbicides, mainly aminocyclopyrachlor and mesotrione, in SS-amended soil. The aim of the present study was to determine the effect of municipal SS applied in agriculture on the sorption–desorption of aminocyclopyrachlor and mesotrione in clay soil. Aminocyclopyrachlor (pyrimidine-2-14C-aminocyclopyrachlor) and mesotrione (cyclohexane-2-14C-mesotrione) sorption–desorption was... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Organic amendments; Tropical soil; Leaching potential; Weak acid. |
| Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87052019000100131 |
| |
|
|
| Jarquín-Sánchez,Aarón; Salgado-García,Sergio; Palma-López,David J; Camacho-Chiu,Wilder. |
| The objective of this study was to predict the concentration of soil organic matter (SOM) in tropical soils using near-infrared spectroscopy (NIRS) for samples measured within a polyethylene bag and without a bag. One hundred and fifty six soil samples from the humid tropics of Tabasco, Mexico with contrasting chemical characteristics were selected. The samples were dried, ground, and sieved through 2 mm and 5 mm screens, and their SOM contents were determined using the Walkley-Black method. The soil samples were packed in polyethylene bags, and SOM was measured directly with and without a bag using a quartz probe (FOSS 5000 model of NIRsystems, DK-3400 Hillerod,Denmark) for a range from 1100 to 2000 nm to obtain a prediction model of SOM. The model for... |
| Tipo: Journal article |
Palavras-chave: Chemical analysis; Tropical soil; Optical fiber; Model; Organic matter prediction. |
| Ano: 2012 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0718-16202012000200015 |
| |
|
|
| Souza,M.D. de; Basssoi,L.H.; Bacchi,O.O.S.; Reichardt,K.; Hermes,L.C.; Abakerli,R.B.; Pilotto,J.E.. |
| Atrazine displacement was studied in a soil profile as a function of water movement and time after herbicide application, taking into account possible influence of preferential flow on leaching. The experiment consisted of two 7 x 7m plots of a dark red latosol (Kanduidalfic Eutrudox), located at Piracicaba, SP, Brazil (22º 43'S and 47º 25'W), 250km inside continent, at an altitude of 580m. One plot was previously treated with 1,000 kg/ha of lime, in order to increase base saturation to 88%, and 500kg/ha of gypsum. Each plot was instrumented with tensiometers, neutron probe access tubes and soil solution extractors, in order to monitor water and atrazine flows. Atrazine was applied at the high rate of 6 kg/ha of active principle. Results showed intensive... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Atrazine; Leaching; Preferential flow; Adsorption; Herbicide; Tropical soil. |
| Ano: 1997 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90161997000300013 |
| |
|
|
| Silva Júnior,Mário Lopes da; Desjardins,Thierry; Sarrazin,Max; Melo,Vânia Silva de; Martins,Paulo Fernando da Silva; Santos,Elaine Rodrigues; Carvalho,Claudio José Reis de. |
| Soil plays an important role in the C cycle, and substitution of tropical forest by cultivated land affects C dynamic and stock. This study was developed in an area of expansion of human settlement in the Eastern Amazon, in Itupiranga, State of Pará, to evaluate the effects of native forest conversion to Brachiaria brizantha pasture on C contents of a dystrophic Oxisol. Soil samples were collected in areas of native forest (NF), of 8 to 10 year old secondary forest (SF), 1 to 2 year old SF (P1-2), 5 to 7 year old SF (P5-7), and of 10 to 12 year old SF (P10-12), and from under pastures, in the layers 0-2, 2-5 and 5-10 cm, to evaluate C levels and stocks and carry out separation of OM based on particle size. After deforestation, soil density increased to a... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Soil carbon stock; Particle-size fractions; Tropical soil; Amazon rain forest. |
| Ano: 2009 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832009000600009 |
| |
|
|
| Silva,Hernani Alves da; Moraes,Anibal de; Carvalho,Paulo César de Faccio; Fonseca,Adriel Ferreira da; Caires,Eduardo Fávero; Dias,Carlos Tadeu dos Santos. |
| Although integrated crop-livestock system (ICLS) under no-tillage (NT) is an attractive practice for intensify agricultural production, little regional information is available on the effects of animal grazing and trampling, particularly dairy heifers, on the soil chemical and physical attributes. The objective of this study was to evaluate the effects of animal grazing on the chemical and physical attributes of the soil after 21 months of ICLS under NT in a succession of annual winter pastures (2008), soybeans (2008/2009), annual winter pastures (2009), and maize (2009/10). The experiment was performed in the municipality of Castro (PR) in a dystrophic Humic Rhodic Hapludox with a clay texture. The treatments included a combination of two pasture (annual... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Tropical soil; Integrated production system; Conservationist agricultural; Soil acidity. |
| Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1806-66902014000500010 |
| |
|
|
| Silveira,Maria Lucia Azevedo; Alleoni,Luís Reynaldo Ferracciú. |
| Cu adsorption, at concentrations between 0 to 800 mg L-1, was evaluated in surface and subsurface samples of three Brazilian soils: a heavy clayey-textured Rhodic Hapludalf (RH), a heavy clayey-textured Anionic ''Rhodic'' Acrudox (RA) and a medium-textured Anionic ''Xanthic'' Acrudox (XA). After adsorption, two consecutive extractions were performed to the samples which received 100 mg L-1 copper. Surface samples adsorbed higher amounts of Cu than the subsurface, and exhibited lower Cu removed after the extractions, reinforcing the influence of the organic matter in the reactions. Cu adsorption was significant in the subsurface horizons of the Oxisols, despite the positive balance of charge, demonstrating the existence of mechanisms for specific... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Adsorption; Isotherms; Desorption; Tropical soil. |
| Ano: 2003 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132003000400006 |
| |
|
|
| Boschi,Raquel Stucchi; Bocca,Felipe Ferreira; Lopes-Assad,Maria Leonor Ribeiro Casimiro; Assad,Eduardo Delgado. |
| ABSTRACT: The aim of this study was to evaluate the performance of pedotransfer functions (PTFs) available in the literature to estimate soil bulk density (ρb) in different regions of Brazil, using different metrics. The predictive capacity of 25 PTFs was evaluated using the mean absolute error (MAE), mean error (ME), root mean squared error (RMSE), coefficient of determination (R2) and the regression error characteristic (REC) curve. The models performed differently when comparing observed and estimated ρb values. In general, the PTFs showed a performance close to the mean value of the bulk density data, considered as the simplest possible estimation of an attribute and used as a parameter to compare the performance of existing models (null model). The... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: REC curve; Model evaluation; Soil database; Tropical soil. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162018000100070 |
| |
|
| |
|
|
| Assis,Cristiane Pereira de; González-Vila,Francisco Javier; Jucksch,Ivo; González-Pérez,Jose Antonio; Neves,Júlio César Lima; Lani,João Luis; Mendonça,Eduardo de Sá. |
| Soil organic matter of a humic Oxisol has been characterized by analyzing litter and soil lipid composition under vegetal covers (coffee, pasture and fragment of native forest). Soil and litter samples were collected from each site at two depths (0-10 and 60-100 cm). Lipid composition was determined by gas chromatography-mass spectrometry (CG-MS). In the solvent extracts of the soil lipids, even-numbered n-alkanoic acids in the range of C16-C32 indicate a soil organic matter input from higher plant waxes. The major compound classes in both the soil and the litter included saturated n-alkanoic acids, with average values in the total spectrum of 58 and 53%, respectively Clear differences in lipid composition were found between the topsoil and subsurface.... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Soil and litter lipid; Soil management; Tropical soil; Grass; Coffee. |
| Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162011000200014 |
| |
|
|
| Vital,Marcos José Salgado; Abranches,Jacqueline; Hagler,Allen Norton; Mendonça-Hagler,Lêda Cristina. |
| The 240 yeasts isolated from soils of the Maracá Ecological Station in the Brazilian Amazon were identified and screened for mycocin production. These strains included 82% of ascomycetous and 18% basidiomicetous affinities and the prevalent species were Candida etchellsii, Candida famata, Candida robusta, Candida rugosa, Candida valida, Debaryomyces hansenii, Cryptococcus albidus, Cryptococcus laurentii, Rhodotorula glutinis, Rhodotorula minuta and Rhodotorula mucilaginosa. Mycocins able to kill some yeasts were produced by 6 strains identified as Issatchenkia sp., Saccharomyces exiguus?, Williopsis saturnus, var. subsufficiens, and 3 W. saturnus according to 26S rDNA D1/D2 region sequence and phenotypic data. |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Mycocins; Killer yeasts; Tropical soil; Issatchenkia; Saccharomyces; Williopsis. |
| Ano: 2002 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822002000300008 |
| |
|
|
| Fonseca,Adriel Ferreira da; Herpin,Uwe; Dias,Carlos Tadeu dos Santos; Melfi,Adolpho José. |
| In this study, an experiment under controlled conditions was carried out to determine the effects of secondary-treated sewage effluent (STSE) application on soil nitrogen concentrations (mineral and total), total carbon and soil pH. The soil and STSE used were collected at Lins, São Paulo State, Brazil. A completely randomized design was used, in completed factorial 4x11 (weekly application rates of 0, 100, 150 and 200 mL STSE per kg soil; and, eleven soil incubation periods from 0 to 10 weeks) with four replicates. The STSE was applied simulating common surface irrigation. Seven days after each incubation period, ammonium and nitrate contents were determined. Additionally, pH and total carbon and nitrogen contents were measured in the soil after 10 weeks.... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Treated sewage effluent; Nitrogen; Carbon; Tropical soil. |
| Ano: 2007 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132007000500001 |
| |
|
| |
|
|
| Ávila,Fabricio William; Faquin,Valdemar; Silva,Douglas Ramos Guelfi; Bastos,Carla Elisa Alves; Oliveira,Nilma Portela; Soares,Danilo Araújo. |
| The effects of foliar and soil applied phosphite on grain yield in common bean (Phaseolus vulgaris L.) grown in a weathered soil under low and adequate phosphate availability were evaluated. In the first experiment, treatments were composed of a 2 x 7 + 2 factorial scheme, with 2 soil P levels supplied as phosphate (40 e 200 mg P dm-3 soil), 7 soil P levels supplied as phosphite (0-100 mg P dm-3 soil), and 2 additional treatments (without P supply in soil, and all P supplied as phosphite). In the second experiment, treatments were composed of a 2 x 3 x 2 factorial scheme, with 2 soil phosphate levels (40 e 200 mg P dm-3 soil), combined with 3 nutrient sources applied via foliar sprays (potassium phosphite, potassium phosphate, and potassium chloride as a... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Phaseolus vulgaris; Tropical soil; Foliar fertilizer; Plant nutrition. |
| Ano: 2012 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1413-70542012000600006 |
| |
|
|
| Pigozzo, Ana Tereza Jordão; UNESP; Lenzi, Ervim; UEM; Luca Júnior, Jorge de; UNESP; Scapim, Carlos Alberto; UEM; Vidigal Filho, Pedro Soares; UEM; Costa, Antônio Carlos Saraiva da; UEM. |
| A avaliação da disponibilidade de micronutrientes pela aplicação de lodo de esgoto foi realizada em campo, para uma safra de milho, em um Latossolo Vermelho distrófico, LVd, de textura média. O delineamento experimental foi de blocos casualizados, com os tratamentos em esquema de parcelas subdivididas, no tempo, sorteados, na parcela, seis doses de lodo de esgoto e, nas subparcelas, as cinco épocas de coleta de solo, com quatro repetições. O lodo de esgoto foi aplicado e incorporado na superfície (0-20 cm). Foram determinados os micronutrientes Fe, Mn, Cu e Zn, nas amostras de solo, e das plantas de milho. No solo, foram extraídas as amostras com solução de DTPA (ácido dietilenotriaminopentaacético) e nas plantas, mediante a digestão nitro-perclórica. A... |
|
Palavras-chave: 5.01.00.00-9 Agronomia lodo de esgoto; Disponibilidade de micronutrientes; Milho; Solo tropical. sewage sludge; Micronutrient availability; Maize; Tropical soil. |
| Ano: 2008 |
URL: http://periodicos.uem.br/ojs/index.php/ActaSciAgron/article/view/5320 |
| |
|
|
| ROCHA,SANDRA M.B.; ANTUNES,JADSON E.L.; ARAUJO,FABIO F. DE; MENDES,LUCAS W.; SOUSA,RICARDO S. DE; ARAUJO,ADEMIR S. F. DE. |
| Abstract: Different physiognomies across the Cerrado could influence the microbial C:N:P ratio in the soil since these physiognomies present different abundance and diversity of plant species. Thus, the aim of this study was to evaluate the microbial C:N:P ratio in soil across three different physiognomies of Cerrado in the Northeast, Brazil, namely campo graminóide (dominance of grasses), cerrado stricto sensu (dominance of grasses, shrubs, low trees, and woody stratum), and cerradão (dominance of woody stratum). Campo graminóide was characterized by lower values of total organic C, N, microbial C:P, N:P, and soil C:N. Cerrado stricto sensu presented average values for most of the measured parameters, while cerradão presented higher values of microbial C,... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Microbial biomass; Soil quality; Organic matter; Tropical soil. |
| Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652019000700857 |
| |
|
|
| Seben Junior,Getulio de Freitas; Corá,José Eduardo; Lal,Rattan. |
| Soils of the tropics are prone to a decrease in quality after conversion from native forest (FO) to a conventional tillage system (CT). However, the adoption of no-tillage (NT) and complex crop rotations may improve soil structural quality. Thus, the aim of this study was to evaluate the physical properties of an Oxisol under FO, CT, and three summer crop sequences in NT: continuous corn (NTcc), continuous soybean (NTcs), and a soybean/corn rotation (NTscr). Both NT and CT decreased soil organic carbon (SOC) content, SOC stock, water stable aggregates (WSA), geometric mean diameter (GMD), soil total porosity (TP), macroporosity (MA), and the least limiting water range (LLWR). However they increased soil bulk density (BD) and tensile strength (TS) of the... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: No-tillage; Soil organic carbon; Soil aggregate; Bulk density; Tropical soil; Cerrado. |
| Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832014000400021 |
| |
|
|
| Santos,Gláucia Cecília Gabrielli dos; Rodella,Arnaldo Antonio; Abreu,Cleide Aparecida de; Coscione,Aline Renée. |
| Phytoremediation is an attractive option to remove metal from contaminated soil since it is a simple, low-cost, and environmentally friendly procedure. To better examine the phytoremediation potential of kenaf (Hybiscus canabinnus), mustard (Brassica juncea), turnip (Raphunus sativus) and amaranth (Amaranthus crentus) plants, a greenhouse experiment was performed in which these species were grown on a soil contaminated with Zn, Cu, Mn, Pb and B. The translocation, the bioconcentration and the removal index, the transference factor and the time to reach 50% of element removal from soil, among other indicators, were used in order to identify a hyperaccumulator. Kenaf plants were more tolerant to the conditions tested, with the highest dry matter production... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Phytorremediation; Tropical soil; Heavy metal. |
| Ano: 2010 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162010000600014 |
| |
| Registros recuperados: 18 | |
|
|
|
