49 results

Desorption, extraction and fractioning of manganese in oxisols

C. W. A. Nascimento, R. L. F. Fontes, J. C. L. Neves

01/Sep/2002

Conflicting results have been achieved by the evaluation of manganese availability in soil, largely a consequence of varying values denoted as available by different extractants. Knowledge on the element’s chemical forms in the soil and on relationships with the available concentrations are important to predict its behavior in the soil-plant system. In this study, six Oxisol soil samples were analyzed to evaluate the influence of liming and different manganese doses on desorption, extraction and fractioning. These soil samples, with and […]

Fractioning, desorption, and chemical extraction of zinc from oxisols

C. W. A. Nascimento, R. L. F. Fontes, J. C. L. Neves, A. C. F. D. Melício

01/Sep/2002

Knowledge of the chemical forms of Zn in the soil and the relationships with soil available concentrations are important for predicting its behavior. This work aimed to study the influence of zinc on the desorption, extraction and fractioning of Zn in samples from six Oxisols. The soil samples, with and without lime application, were kept incubated for 30 days after receiving Zn doses (0.0, 20, and 40 mg dm-3). After incubation, the micronutrient was extracted with Mehlich-1, Mehlich-3, DTPA and […]

Nutrient losses by erosion as affected by different methods of native grassland improvement in the state of Rio Grande do Sul, Brazil

E. A. Cassol, R. Levien, I. Anghinoni, M. P. Badelucci

01/Sep/2002

Growth stagnation on native grassland during the winter season has stimulated the introduction of winter species in order to increase forage offer for animals in the State of Rio Grande do Sul, Brazil. To determine the nutrient losses by erosion as affected by different methods of native grassland improvement, an experiment was carried out at the Agronomic Experimental Station of the Federal University of Rio Grande do Sul, in Eldorado do Sul. A mixture of the winter forage species black […]

Effects of compaction and CaCO3 on the kinetics of pyrite oxidation in coal mining spoil

E. R. Soares, J. W. V. Mello, M. L. T. Corrêa, L. M. Costa, C. E. G. R. Schaefer

01/Mar/2002

Acid drainage, resulting from sulfide oxidation, is an environmental problem which may impair soil and water sources quality. Such impact may occur in several environments, but it is commonly related to coal mining. This work was carried out to study the kinetics of pyrite oxidation in coal mining spoil from Candiota (RS) Brazil, under different conditions of atmospheric O2 access and pH. The study aimed to evaluate the possibility of adjusting carbonate dissolution rate to the sulfide oxidation rate in […]

Alternative use of super heavy harrow plow for soil acidity liming and black oat production

R. M. Prado, C. G. Roque

01/Mar/2002

Maximum liming efficiency depends not only on the quality of the corrective material but also on appropriate incorporation according to depth and homogeneity.Based on this, this work aimed to evaluate the effect of limestone incorporation ways on the production of black oat and on the correction of acidity in soil profile.An experiment was carried out in a Typic Acrustox loamy texture, in the area of the Triângulo Mineiro in Uberlândia (MG) from May 1995 to February 1996.The experiment was arranged […]

Liming influence on shoot dry matter yield of green manure green manure – cover crops under greenhouse conditions

P. R. Ernani, C. Bayer, S. M. V. Fontoura

01/Dec/2001

Amelioration of degraded soils is time-consuming and expensive. Green manure and cover crops have been widely used in this remediation process since these plants produce a large amount of phytomass at a low cost, especially if they are tolerant to soil acidity. This study was carried out to evaluate the effect of liming on dry matter yield of the following 16 species, under greenhouse conditions: eight winter crops (Lollium multiflorum, Avena strigosa, Lathyrus sativus, Lupinus angustifolius, Pisum sativum, Secale cereale, […]

Influence of phosphorus and liming combination on corn yield

P. R. Ernani, J. A. L. Nascimento, M. L. Campos, R. J. Camillo

01/Sep/2000

The existence of soil exchangeable Al in toxic levels inhibits root growth and elongation, with negative effects on water and nutrient uptake, especially of P. Thus, as soil P increases, plants become less dependent on a large root system, that may decrease crop response to liming. This study was carried out to evaluate the effect of liming and phosphorus fertilization on corn yield. The experiment was conducted in Lages, Southern Brazil, from 1994 to 1998, in a clayed Oxisol (Hapludox) […]

Physical and electrochemical properties of a Brown Latosol as affected by liming

J. A. Albuquerque, C. Bayer, P. R. Ernani, E. C. Fontana

01/Jun/2000

Liming influences some electrochemical properties of soils of variable charge that may affect clay dispersion and aggregate stability. This hypothesis was tested after five years of incorporation of increasing rates of limestone (0, 4.5, 9.0, 13.5 and 18 t ha-1) into a Brown Latosol (Haplohumox). Dolimitic limestone was plowed down to 17 cm depth into the soil during the spring of 1992 when field plots began to be cultivated annually with continuous corn. Soil samples used in this work were […]

Residual effect of lime on corn and soybean production in a Low Humic Gley soil

L. N. Miranda, J. C. C. Miranda

01/Mar/2000

Growing corn and soybean in acid soils requires lime application to raise the soil pH to reduce the aluminum toxicity and to add the nutrients calcium and magnesium. The residual effect of liming may last for several years of successive cropping. To evaluate this effect, an experiment was carried out in a Low Humic Gley soil in the EMBRAPA Cerrados Research Center, with the broadcasting application of lime levels of 0, 2, 4, 6 and 8 t ha-1, beginning in […]

Carbon, nitrogen and sulfur in particle size fractions of two oxisols submitted to the addition of liming and phosphorus

C. A. Silva, S. J. Anderson, F. R. Vale

01/Sep/1999

The amount and distribution of carbon, nitrogen, and sulfur in whole soil and in particle-size fractions were analyzed in two clayey Dark Red Latosols (LE1 and LE2). LE1 (forest as natural vegetation), from Cordeirópolis, São Paulo, cultivated with citrus since 1982 receiving two lime treatments, control and 18 t ha-1 applied twice in 1983 and 1994. Since 1976, LE2 (cerrado as natural vegetation) from Planaltina, Federal District (cerrado region), was cultivated with different crops (wheat, soybean, rice and sorghum) sown […]

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