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Efeito da calagem na mineralização de 14C-glifosato em solos; Effect of liming on the mineralization of 14C-glyphosate in soils

ARANTES, Sayonara Andrade do Couto Moreno; LAVORENTI, Arquimedes; TORNISIELO, Valdemar Luiz
Fonte: Editora da Universidade Federal de Lavras Publicador: Editora da Universidade Federal de Lavras
Tipo: Artigo de Revista Científica
POR
Relevância na Pesquisa
36.23%
A calagem é uma prática de manejo da fertilidade muito utilizada e considerada essencial em solos tropicais. Essa prática, por influenciar as propriedades físicas, químicas e biológicas dos solos, pode também alterar o comportamento de moléculas orgânicas. Objetivou-se, neste estudo, avaliar o efeito da calagem na mineralização do herbicida glifosato em um Latossolo Vermelho (LE) e em um Neossolo Quartzarênico (RQ) e também na atividade microbiana dos mesmos solos. Os experimentos foram conduzidos em delineamento inteiramente casualizado em esquema fatorial 2 x 2, correspondendo a dois solos e a duas condições de manejo (com e sem calagem). Para o ensaio de mineralização, técnicas radiométricas foram utilizadas para avaliar a evolução do 14CO2 a intervalos de 7 dias, durante 70 dias. O estudo de atividade microbiana foi conduzido paralelamente ao experimento de mineralização, usando a metodologia de glicose radiomarcada (14C-glicose), a qual foi avaliada a intervalos de quatorze dias, durante 70 dias. Pelos resultados, foi possível verificar que nos dois solos estudados, a calagem aumentou significativamente a mineralização do 14C-glifosato e a atividade da microbiota.; Liming is a widely used soil fertility management practice and essential in tropical soils. This practice...

Acidity and Aluminum Speciation as Affected by Surface Liming in Tropical No-Till Soils

ALLEONI, Luis R. F.; CAMBRI, Michel A.; CAIRES, Eduardo F.; GARBUIO, Fernando J.
Fonte: SOIL SCI SOC AMER Publicador: SOIL SCI SOC AMER
Tipo: Artigo de Revista Científica
ENG
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Aluminum toxicity is one of the major soil factors limiting root growth in acidic soils. Because of the increase in organic matter content in the upper few centimeters of soils under no-till systems (NTS), most Al in soil solution may be complexed to dissolved organic C (DOC), thus decreasing its bioavailability. The aim of this study was to evaluate the effects of surface liming on Al speciation in soil solution in Brazilian sites under NTS. Field experiments were performed in two regions with contrasting climates and levels of soil acidity: Rondonopolis, Mato Grosso State, on a Rhodic Haplustox, and Ponta Grossa, Parana State, on a Typic Hapludox. The treatments consisted of a control and three lime rates, surface applied to raise the base saturation to 50, 70, and 90%. Soil solution was obtained at soil water equilibrium (1:1 w/w soil/water ratio). The effects of surface liming on soil chemical attributes and on the composition of the soil solution were dependent on weather conditions, time under NTS, and soil weathering. Most Al in soil solution was complexed to DOC, representing about 70 to 80% of the total Al at pH <5.0, and about 30 to 4096 at pH >5.0. Under pH 5.5, the results were closely correlated with the solubility line for amorphous Al. Organic complexes may control Al(3+) release into soil solution at pH <5.5. Results suggest that in areas under NTS for a long period of time...

Cadmium Uptake by Lettuce (Lactuca sativa L.) as Basis for Derivation of Risk Limits in Soils

Melo, Leônidas Carrijo Azevedo; Alleoni, Luis Reynaldo Ferracciú; Swartjes, Frank Albert; Silva, Evandro Barbosa da
Fonte: TAYLOR & FRANCIS INC; PHILADELPHIA Publicador: TAYLOR & FRANCIS INC; PHILADELPHIA
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
36.05%
The availability and uptake of Cd by lettuce (Lactuca sativa L.) in two common tropical soils (before and after liming) were studied in order to derive human health-based risk soil concentration. Cadmium concentrations ranging from 1 to 12 mg kg(-1) were added to samples from a clayey Oxisol and a sandy-loam Ultisol under glasshouse conditions. After incubation, a soil sample was taken from each pot, the concentration of Cd in the soil was determined, lettuce was grown during 36 d, and the edible parts were harvested and analyzed for Cd. A positive linear correlation was observed between total soil Cd and the Cd concentration in lettuce. The amount of Cd absorbed by lettuce grown in the Ultisol was about twice the amount absorbed in the Oxisol. Liming increased the soil pH and slightly reduced Cd availability and uptake. CaCl2 extraction was better than DTPA to reflect differences in binding strength of Cd between limed and unlimed soils. Risk Cd concentrations in the Ultisol were lower than in the Oxisol, reflecting the greater degree of uptake from the Ultisol. The derived risk Cd values were dependent on soil type and the exposure scenario.; Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP); Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP) [07/56350-9]

Calagem e formas de alumínio em três localidades sob sistema de plantio direto.; Liming and aluminum forms in three places under no-tillage system.

Cambri, Michel Alexandro
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 16/08/2004 PT
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No Brasil existem diversas áreas agrícolas sob sistema de plantio direto (SPD), cujos solos apresentam pH baixo e teor alto de alumínio trocável. Apesar da aparente condição desfavorável ao cultivo agrícola de tais áreas, geralmente ocorrem altas produções e ausência de resposta das culturas à calagem. Isto está ligado, possivelmente, ao comportamento químico do alumínio em solos manejados no SPD, em que o acúmulo de matéria orgânica (MO) e as interações entre compostos orgânicos solúveis e os minerais do solo geram condições para a complexação do alumínio, deixando-o numa forma menos tóxica às plantas. Estudou-se o comportamento químico do alumínio no SPD em amostras de experimentos de três localidades brasileiras situadas em Rondonópolis/MT, Ponta Grossa/PR e Botucatu/SP, correlacionando-o com a matéria orgânica (quantidade e qualidade) e com a constituição mineralógica dos solos, bem como com a produção das culturas a campo. O alumínio foi estudado em diferentes condições de pH, obtidas após adição de calcário em superfície. Foi realizada a especiação química do Al na solução do solo, e separação e identificação dos ligantes orgânicos de maior efeito na redução da toxidez do elemento. A complexação do Al pela matéria orgânica foi estudada após extração com CuCl2 0...

Calagem e as propriedades eletroquímicas e físicas de um latossolo em plantio direto; Liming effect on electrochemical and physical properties of a no-tilled oxisol

Costa, Falberni de Souza; Bayer, Cimelio; Albuquerque, Jackson Adriano; Fontoura, Sandra Mara Vieira
Fonte: Universidade Federal do Rio Grande do Sul Publicador: Universidade Federal do Rio Grande do Sul
Tipo: Artigo de Revista Científica Formato: application/pdf
POR
Relevância na Pesquisa
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Neste estudo, avaliou-se (i) o efeito da calagem nas propriedades eletroquímicas e físicas de um Latossolo Bruno há 21 anos em plantio direto (PD), bem como (ii) o efeito do revolvimento do solo para a incorporação de calcário sobre as suas propriedades físicas. A calagem aumentou o potencial elétrico superficial do solo, independente do modo de aplicação de calcário, cujos valores estimados variaram de (–) 90 mV a (–) 118mV. Entretanto, a argila dispersa em água não aumentou, o que pode ter sido devido à sua relação inversa com o carbono orgânico total (COT) (r2=0,80) e Ca+Mg (r2=0,56), cujos maiores teores foram verificados na camada superficial do solo. O diâmetro médio geométrico (DMG) dos agregados não foi afetado pela calagem, e teve uma relação positiva com os teores de COT (r2=0,89) das diferentes camadas de solo. Após 5 anos, não se verificou efeito negativo do revolvimento do solo para a incorporação de calcário sobre o DMG dos agregados e na porosidade deste solo argiloso (690g kg-1 argila) e de mineralogia predominantemente gibsítica. Além das condições favoráveis à atividade microbiana, maiores teores de COT e de Ca e Mg na camada superficial de solos em PD contribuem para a mitigação do efeito dispersivo da calagem.9; In this study there has been an evaluation of (i) the liming effect on some electrochemical and physical properties of a no-tilled Oxisol (Haplohumox) for 21 years...

Alterações nos atributos químicos de um Latossolo distroférrico decorrentes da granulometria e doses de calcário em sistemas plantio direto e convencional

Mello, J. C. A.; Villas Bôas, R. L.; Lima, E. V.; Crusciol, C. A. C.; Bull, Leonardo Theodoro
Fonte: Sociedade Brasileira de Ciência do Solo Publicador: Sociedade Brasileira de Ciência do Solo
Tipo: Artigo de Revista Científica Formato: 553-561
POR
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Atualmente, percebe-se o interesse na calagem superficial, sem prévia incorporação, para instalação do sistema plantio direto (SPD). Dessa forma, objetivou-se determinar os efeitos de granulometria e doses de calcários no SPD, em fase de implantação, e no sistema de plantio convencional (SPC) sobre o pH, H + Al, Ca2+ e Mg2+. O experimento foi realizado no ano agrícola de 1998/99, na FCA/UNESP-Botucatu (SP), em Latossolo Vermelho. O delineamento experimental foi de blocos ao acaso, com parcelas subsubdivididas e quatro repetições. As parcelas representaram os sistemas de plantio (SPD e SPC); as subparcelas, a granulometria dos calcários [grosso (PRNT = 56 %) e fino (PRNT = 90 %)], e as subsubparcelas, as doses de 2, 4 e 6 t ha-1 (calcário grosso) e 1,2; 2,4 e 3,6 t ha-1 (fino). O solo foi amostrado, a 0-5, 5-10, 10-20 e 20-40 cm de profundidade, 1, 3 e 12 meses após a aplicação dos corretivos. A análise de variância não detectou interação tripla entre os fatores. A aplicação de calcário superficial no SPD, independentemente da granulometria e da dose, alterou positivamente os atributos químicos do solo (0-5 e 5-10 cm), 12 meses após a calagem. O corretivo continuou reagindo, independentemente do sistema de plantio...

Boron adsorption in lowland soils from Parana State, Brazil

Steiner, Fabio; Lana, Maria do Carmo; Zoz, Tiago; Fey, Rubens; Frandoloso, Jucenei Fernando
Fonte: Universidade Estadual de Londrina (UEL) Publicador: Universidade Estadual de Londrina (UEL)
Tipo: Artigo de Revista Científica Formato: 1391-1401
ENG
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Boron adsorption by soil is the main phenomenon that affects its availability to plants. This, the present study investigated the effect of liming on B adsorption by lowland soils of Parana State, and to correlate these values with the physical and chemical properties of the soils. Surface samples of three lowland soils [Gleissolo Haplico (GX), Plintossolo Haplico (FX) and Cambissolo Haplico (CX)], with different origin material and physicochemical properties were used. Samples with or without liming application were incubated during 60 days. Boron adsorption was accomplished by shaking 4.0g soil samples, for 24 h, with 20 mL of 0.01 mol L-1 CaCl2 solution containing different concentrations of B (0, 1, 2, 4, 8 and 16 mg L-1). Sorption was fitted to non-linear form of the Langmuir adsorption isotherm. The adsorption isotherms indicated that the B adsorption increased with its increasing concentration in the equilibrium solution. Maximum adsorption capacity of B ranged from 3.0 to 13.9 mg kg(-1) (without liming) and 14.7 to 35.7 mg kg(-1) (with liming). Liming increased the amount of adsorbed B in Gleissolo Haplico and Plintossolo Haplico soils, although the bonding energy has decreased. The amount of adsorbed B by Cambissolo Haplico soil was not affected by liming application. The most important soil properties affecting the B adsorption in lowland soils were pH...

Effect of pH on boron adsorption in some soils of Parana, Brazil

Steiner, Fabio; Lana, Maria do Carmo
Fonte: Inst Investigaciones Agropecuarias Publicador: Inst Investigaciones Agropecuarias
Tipo: Artigo de Revista Científica Formato: 181-186
ENG
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Temporary B deficiency can be triggered by liming of acid soils because of increased B adsorption at higher soil pH. Plants respond directly to the activity of B in soil solution and only indirectly to B adsorbed on soil constituents. Because the range between deficient and toxic B concentration is relatively narrow, this poses difficulty in maintaining appropriate B levels in soil solution. Thus, knowledge of the chemical behavior of B in the soil is particularly important. The present study investigated the effect of soil pH on B adsorption in four soils of Parana State, and to correlate these values with the physical and chemical properties of the soils. Surface samples were taken from a Rhodic Hapludox, Arenic Hapludalf, Arenic Hapludult, and one Typic Usthorthent. To evaluate the effect of pH on B adsorption, subsamples soil received the application of increasing rates of calcium carbonate. Boron adsorption was accomplished by shaking 2.0 g soil, for 24 h, with 20 mL of 0.01 mol L-1 NaCl solution containing different concentrations (0.0, 0.1, 0.2, 0.4, 0.8, 1.2, 1.6, 2.0, and 4.0 mg B L-1). Sorption was fitted to non-linear form of the Langmuir adsorption isotherm. Boron adsorption increased as concentration increased. Boron adsorption was dependent on soil pH...

Short-term effects on soil properties and wheat production from secondary paper sludge application on two Mediterranean agricultural soils

Nunes, J. Rato; Cabral, F.; López-Piñeiro, A.
Fonte: Elsevier Publicador: Elsevier
Tipo: Artigo de Revista Científica
Publicado em //2008 ENG
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This study was conducted under greenhouse conditions to evaluate the potential use of SPS as a fertilizer, amendment and/or liming agent for wheat (Triticum aestivum L.). Two representative Mediterranean agricultural soils, a Cambic Arenosol (cmAR) and a Cromic Cambisol (crCM) were used. Treatments included four sludge rates ranging from 0 to 40 g kg 1 (equivalent of 0, 38, 88 and 120 Mg ha 1). A significant increment in soil pH, organic carbon, N total, available P and exchangeable K were observed in both soils. Sludge application significantly increased N and decreased Zn, Mn and Cu concentrations in wheat. Wheat grain yields were reduced by 33% and 37% when 120 Mg SPS ha 1 was applied to cmAR and crCM soils, respectively, due apparently to unavailability of Mg. However, straw yields, with much lower Mg requirements, increased significantly with SPS rates. Secondary pulp mill sludge seems to be a potential source of organic matter, N, P, K and a potential soil amendment liming agent for acid soils, when appropriate supplemental fertilizer was provided. For grain crops grown in these soils, addition of Mg is required for proper nutrient balance.

Availability of a soluble phosphorus source applied to soil samples with different acidicity levels

Viégas,Ricardo Almeida; Novais,Roberto Ferreira; Schulthais,Fernanda
Fonte: Sociedade Brasileira de Ciência do Solo Publicador: Sociedade Brasileira de Ciência do Solo
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2010 EN
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Considerations on the interactions of P in the soil-plant system have a long history, but are still topical and not yet satisfactorily understood. One concern is the effect of liming before or after application of soluble sources on the crop yield and efficiency of available P under these conditions. The aim of this study was to evaluate the effect of soil acidity on availability of P from a soluble source, based on plant growth and chemical extractants. Nine soil samples were incubated with a dose of 200 mg kg-1 P in soil with different levels of previously adjusted acidity (pH H2O 4.5; 5.0; 5.5; 6.0 and 6.5) and compared to soils without P application. After 40 days of soil incubation with a P source, each treatment was limed again so that all pH values were adjusted to 6.5 and then sorghum was planted. After the first and second liming the P levels were determined by the extractants Mehlich-1, Bray-1 and Resin, and the fractionated inorganic P forms. In general, the different acidity levels did not influence the P availability measured by plant growth and P uptake at the studied P dose. For some soils however these values increased or decreased according to the initial soil pH (from 4.5 to 6.5). Plant growth, P uptake and P extractable by Mehlich-1 and Bray-1 were significantly correlated...

Reduction of exchangeable calcium and magnesium in soil with increasing pH

Miyazawa,Mário; Pavan,Marcos A.; Ziglio,Cláudio O.; Franchini,Júlio C.
Fonte: Instituto de Tecnologia do Paraná - Tecpar Publicador: Instituto de Tecnologia do Paraná - Tecpar
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2001 EN
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A laboratory study was conducted with soil samples and synthetic solutions to investigate possible mechanisms related with reduction in KCl exchangeable Ca and Mg with increasing pH. Increasing soil pH over 5.3 with CaCO3 added to the soil and with NaOH solution added to soil/KCl suspension increased adsorptions of Ca and Mg. The reduction of Mg was greater than Ca and was related to the concentration of soil exchangeable Al. The decreases of soluble Ca and Mg following addition of Al in synthetic solution were at pH > 7.5. The isomorphic coprecipitation reaction with Al compounds may be the most possible mechanism responsible for the decrease of exchangeable Ca and Mg with increasing pH. Possible chemical reactions are presented.

Soil TPH Concentration Estimation Using Vegetation Indices in an Oil Polluted Area of Eastern China

Zhu, Linhai; Zhao, Xuechun; Lai, Liming; Wang, Jianjian; Jiang, Lianhe; Ding, Jinzhi; Liu, Nanxi; Yu, Yunjiang; Li, Junsheng; Xiao, Nengwen; Zheng, Yuanrun; Rimmington, Glyn M.
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Publicado em 16/01/2013 EN
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55.77%
Assessing oil pollution using traditional field-based methods over large areas is difficult and expensive. Remote sensing technologies with good spatial and temporal coverage might provide an alternative for monitoring oil pollution by recording the spectral signals of plants growing in polluted soils. Total petroleum hydrocarbon concentrations of soils and the hyperspectral canopy reflectance were measured in wetlands dominated by reeds (Phragmites australis) around oil wells that have been producing oil for approximately 10 years in the Yellow River Delta, eastern China to evaluate the potential of vegetation indices and red edge parameters to estimate soil oil pollution. The detrimental effect of oil pollution on reed communities was confirmed by the evidence that the aboveground biomass decreased from 1076.5 g m−2 to 5.3 g m−2 with increasing total petroleum hydrocarbon concentrations ranging from 9.45 mg kg−1 to 652 mg kg−1. The modified chlorophyll absorption ratio index (MCARI) best estimated soil TPH concentration among 20 vegetation indices. The linear model involving MCARI had the highest coefficient of determination (R2 = 0.73) and accuracy of prediction (RMSE = 104.2 mg kg−1). For other vegetation indices and red edge parameters...

Impaired Reduction of N2O to N2 in Acid Soils Is Due to a Posttranscriptional Interference with the Expression of nosZ

Liu, Binbin; Frostegård, Åsa; Bakken, Lars R.
Fonte: American Society of Microbiology Publicador: American Society of Microbiology
Tipo: Artigo de Revista Científica
Publicado em 24/06/2014 EN
Relevância na Pesquisa
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Accumulating empirical evidence over the last 60 years has shown that the reduction of N2O to N2 is impaired by low soil pH, suggesting that liming of acid soils may reduce N2O emissions. This option has not gained much momentum in global change research, however, possibly due to limited understanding of why low pH interferes with N2O reductase. We hypothesized that the reason is that denitrifying organisms in soils are unable to assemble functional N2O reductase (N2OR) at low pH, as shown to be the case for the model strain Paracoccus denitrificans. We tested this by experiments with bacteria extracted from soils by density gradient centrifugation. The soils were sampled from a long-term liming experiment (soil pH 4.0, 6.1, and 8.0). The cells were incubated (stirred batches, He atmosphere) at pH levels ranging from 5.7 to 7.6, while gas kinetics (NO, N2O, and N2) and abundances of relevant denitrification genes (nirS, nirK, and nosZ) and their transcripts were monitored. Cells from the most acidic soil (pH 4.0) were unable to reduce N2O at any pH. These results warrant a closer inspection of denitrification communities of very acidic soils. Cells from the neutral soils were unable to produce functional N2OR at pH values of ≤6.1...

Lime-micronutrient studies with soils from Costa Rica and the eastern Llanos of Colombia

Rodriguez-Gomez, Marciano, 1936-
Fonte: Universidade da Flórida Publicador: Universidade da Flórida
Tipo: Artigo de Revista Científica Formato: xvii, 258 leaves : ill. ; 28 cm.
Publicado em //1974 ENGLISH
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(Thesis) Thesis (Ph. D.)--University of Florida, 1974.; (Bibliography) Includes bibliographical references (leaves 229-256).; Typescript.; Vita.; (Statement of Responsibility) by Marciano Rodriguez-Gomez.

Peanut response to lime and molybdenum application in low pH soils

Quaggio,J. A.; Gallo,P. B.; Owino-Gerroh,C.; Abreu,M. F.; Cantarella,H.
Fonte: Sociedade Brasileira de Ciência do Solo Publicador: Sociedade Brasileira de Ciência do Solo
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2004 EN
Relevância na Pesquisa
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Liming acid soils is considered to assure the availability of Mo in crops. Additionally, in peanuts (Arachis hypogaea L.) the positive response to liming is associated to a better supply of Ca+2, Mo for the nitrogenase-complex activity, and other non-nitrogen fixing activities of the crop. This study was thus undertaken to assess the effect of lime, Mo, and the lime-Mo interaction on peanut crop, on an acid Ultisol at the Mococa Experimental Station, Instituto Agronômico, São Paulo State, Brazil, from 1987 to 1990. A randomized complete block design with four replications, in a 4 x 4 factorial arrangement, was used in the study. The factors included four lime rates (0, 2, 4, and 6 t ha-1) broadcast and incorporated into the soil, and Mo (0, 100, 200, and 300 g ha-1) as (NH4)2MoO4 applied as seed dressing. Lime was applied once at the beginning of the study while Mo was applied at every planting. Peanut seed cv 'tatu' was used. Significant increase in peanut kernel yield with liming was only evident in the absence of Mo, whereas the peanut response to Mo was observed in two out of the three harvests. A higher yield response (28 % increase) was found when Mo was applied without liming. Soil molybdenum availability, as indicated by plant leaf analysis...

The leaching of trifloxysulfuron-sodium and pyrithiobac-sodium in soil columns as a function of soil liming

Guerra,Naiara; Oliveira Júnior,Rubem Silvério de; Constantin,Jamil; Oliveira Neto,Antonio Mendes de; Dan,Hugo de Almeida; Braz,Guilherme Braga Pereira
Fonte: Editora da Universidade Estadual de Maringá - EDUEM Publicador: Editora da Universidade Estadual de Maringá - EDUEM
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2013 EN
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36.18%
Scarce research has been published concerning the effect of soil pH on the leaching potential of herbicides in tropical soils. Thus, we designed this study to evaluate the influence of soil liming on the leaching of trifloxysulfuron-sodium and pyrithiobac-sodium after simulated rainfall depths in soil columns. In the study, two trials were conducted simultaneously; the first experiment evaluated trifloxysulfuron-sodium (7.5 g ha-1), while the second experiment evaluated pyrithiobac-sodium (70 g ha-1). Both experiments were conducted in a randomized block design with a 2 x 4 x 5 factorial scheme and four replications. The design's factors corresponded to 2 soil liming conditions (with or without liming), 4 simulated rainfall depths (0, 15, 30, and 45 mm) and 5 depths in the soil column (0-5, 5-10, 10-15, 15-20, and 20-25 cm). The trials were repeated, and only the source for the soil neutralization was changed, i.e., dolomitic limestone in Experiment 1 and calcium oxide in Experiment 2. Compared to trifloxysulfuronsodium, the herbicide pyrithiobac-sodium indicated a greater potential for leaching. With more acidic soils, the leaching potential in limed soils was greater for both herbicides. Only the liming that used calcium oxide provided a significant leaching of trifloxysulfuron-sodium for depths greater than 20 cm. Simulated rainfall > 15 mm provided leaching of pyrithiobac-sodium to a depth of 25 cm at near-neutral soil pH values.

Crescimento do maracujazeiro-doce (Passiflora alata Dryand.) em função da calagem, classes de solo e tipos de muda

Fonseca, Elda Bonilha Assis
Fonte: Universidade Federal de Lavras; Programa de Pós-graduação em Fitotecnia; UFLA; brasil; Departamento de Agricultura Publicador: Universidade Federal de Lavras; Programa de Pós-graduação em Fitotecnia; UFLA; brasil; Departamento de Agricultura
Tipo: Tese de Doutorado
Publicado em 15/12/2015 POR
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Aiming to study the effect of the liming on the growth and nutrition of sweet passion fruit plants, two experiments were carried out in the greenhouse of the Agriculture Department of the Federal University of Lavras (UFLA). The statistical design used was randomized blocks in a factorial scheme (2x4) + 2, with four replications. The treatments involved two soil classes (Dystrophic Red-Yellow Latosol - LVAd and Dystrophic Red Latosol - LVd), four base saturation leveis (40%, 60%, 80% and 100%) and two more additional treatments, LVAd without liming and LVd without liming. The fírst experiment was carried out with seedlings (originated from seeds) and the second with cuttings. The experimental plot was constituted of four vases in the fírst experiment and two vases in the second. After 150 days, the stem length, number ofleaves, dry matter ofshoots and roots, the roots/shoots ratio, macro and micronutrients contents in the shoots dry matter and P, Ca and Mg in the roots dry matter were evaluated. It was concluded that in both experiments the largest growth happened in the LVd and the sweet passion fruit tolerates soils with low base saturation leveis. In the fírst experiment, with seedlings, the increase ofbase saturation leveis reduced vegetative growth ofplants in the LVd but had no influence in the LVAd. For both soil classes...

Liming and glyphosate effect in the microbial activity of different classes of soils; EFEITO DA CALAGEM E DO GLIFOSATO NA ATIVIDADE MICROBIANA DE DIFERENTES CLASSES DE SOLOS

Arantes, Sayonara Andrade do Couto Moreno; Escola Superior de Agricultura "Luiz de Queiroz" - Esalq; Lavorenti, Arquimedes; Escola Superior de Agricultura "Luiz de Queiroz"; Tornisielo, Valdemar Luiz; Centro de Energia Nuclear na Agricultura
Fonte: UFPR Publicador: UFPR
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; Artigo Avaliado pelos Pares Formato: application/pdf
Publicado em 19/02/2008 POR
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Management practice may influence the microbial activity of the soils. Liming is an essential practice and used very much for the cultivation of the brazilian soils. Glyphosate is widely used for weed management control of several cultures. The objective of this study was to verify the effect of liming practice and the use of glyphosate herbicide in the microbial activity of a Quartzarenic Neosol (RQ) and Red Latosol (LE) soils. The soil samples were collected in the area of Piracicaba, São Paulo State, in the 0 – 20 cm layer and incubated in Bartha flasks. The humidity of the soils was elevated to 60% of field capacity and incubated under temperature controlled.. The microbial activity was evaluated in the days 0, 14, 28, 42, 56 e 70, by the method of the radiorespirometry using 14C-glucose. The microbial activity varied along the 70 days of evaluation and all the treatments behaved in a similar manner. In the absence of the glyphosate, the liming increased significantly the microbial activity in LE and RQ. However, in the presence of herbicide, the liming had positive and significative effect only in LE. In the two soils treated with liming, the glyphosate reduced the microbial activity. Soil microbial activity was affected by liming as well as glyphosate.; O objetivo deste trabalho foi verificar o efeito da calagem e do herbicida glifosato na atividade microbiana em Neossolo Quartzarênico (RQ) e em Latossolo Vermelho (LE). As amostras dos dois solos foram coletadas na região de Piracicaba (SP)...

MOBILITY OF THE ATRAZINE HERBICIDE IN SAMPLES OF RED LATOSOLS UNDER LIMING AND PHOSPHATE FERTILIZATION; MOBILIDADE DO HERBICIDA ATRAZINA EM AMOSTRAS DE LATOSSOLOS VERMELHOS SOB CALAGEM E ADUBAÇÃO FOSFATADA

VASCONCELOS, FERNANDA CARLA WASNER; Universidade Federal de Lavras; NÓBREGA, JÚLIO CÉSAR AZEVEDO; Universidade Federal do Piauí; GUERREIRO, MÁRIO CÉSAR; Universidade Federal de Lavras; JESUS, ELEN ALVARENGA DE; Universidade Federal de Lavras; JULIÃ
Fonte: UFPR Publicador: UFPR
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; Artigo Avaliado pelos Pares Formato: application/pdf
Publicado em 03/02/2009 POR
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The objective of this study was to evaluate the effect of liming and phosphate fertilization practices, separately or in set, on the atrazine leaching in Red Latosols samples with distinct iron oxide purports (in lysimeters), under laboratory conditions. The treatments had been ruled in totally randomized experimental design, factorial design 2 x 2, being the following factors tested: soils in two conditions of phosphorus (with and without phosphate), and two conditions of liming (with and without liming), with three repetitions, totalizing 12 experimental parcels for each soil. Atrazine was applied in dose corresponding to 6 L per hectar of Gesaprim 500® and had been simulated rains of 18.75 mm to each three days during the period of 30 days. The solid sampled material was prepared for extration of atrazine and quantified by gas chromatograph, equipped with detector of nitrogen and phosphorus (GC-NPD). The results showed that, independently of soils and liming and phosphate fertilization practices, atrazine presents mobility, because it was found in practically all the studied depths. Separately, liming and phosphate fertilization practices reduce the atrazine concentration in the ground, being this effect more significant when under liming in both soils. The liming and phosphate fertilization effects...

Application of sugar foam to vineyard acid soils under Mediterranean conditions

Olego,M.A.; Coque,J.J.R.; Garzón Jimeno,E.
Fonte: South African Journal of Enology and Viticulture Publicador: South African Journal of Enology and Viticulture
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2014 EN
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46.05%
Calcium (Ca) deficiency and aluminium (Al) toxicity are considered major chemical constraints that limit vine growth in vineyard acid soils under Mediterranean conditions. The main aim of this work was to evaluate the effects of three doses of sugar foam (900, 1 800 and 2 700 kg CaCO3/ha) on five soil properties (pH in water, Ca, Mg, K and Al exchangeable contents) and Ca concentrations in petioles and canes of one wine grape variety. Research was conducted over three seasons (2006 to 2008) in a random block design at León (Spain). The results for plants and soils were subjected to general lineal model analysis. As a result, one linear model, validated through a cross-validation procedure, has been proposed to predict exchangeable calcium levels in vineyard acid soils at véraison. Based on the results for the soils, the higher doses of sugar foam (1 800 and 2 700 kg CaCO3/ha) were the most effective doses in decreasing Al exchangeable and increasing Ca exchangeable contents. In addition, liming increased Ca content in petioles and decreased Ca content in canes, but in both cases these differences were not significant.