Viçosa, Brazil
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Victor Hugo Alvarez A.,Federal University of Viçosa | Santos A.F.,DPS UFV | dos Santos G.L.A.A.,State University of Mato Grosso do Sul | da Matta P.M.,DPS UFV
Revista Brasileira de Ciencia do Solo | Year: 2014

The recommendation of a fertilizer dose for a crop depends on nutrient gain-loss balance in the agricultural system (Restitution Law). At the Federal University of Viçosa (UFV), this balance has been modeled for liming and fertilizer recommendations for eucalyptus (NUTRICALC), pineapple, cotton, rice, banana, coffee, sugarcane, coconut, orange, melon, maize, pastures, soybean, tomato (FERTICALC), and for teak (FERTI - UFV). Fertilization and nutrition of tropical ornamental plants is based on the knowledge of growers and fertilizer manufacturers. This study was developed to establish an experimental technique for determining: recovery rates of available forms of macro and micronutrients by extractors; nutrient demand and recovery rates of ornamental plants; as well as nutrient doses and contents in fertilizer which supplies plant requirements. The modeling focused on two modules. Plant module, in which nutrient demand and requirement for a given yield are obtained; and substrate module, that allows to calculate nutrient supply from the pot or bed used for cultivation. Modeling enabled to outline a new research method for lime and fertilizer recommendations of crops with insufficient information, particularly for tropical ornamental plants. The requirement - supply method allows to determine nutrient dose and content of supply fertilizer (SF) that meets plant requirement. The method is iterative and was developed in three approaches. The first one considered the production of orchid seedlings. In the second, growth curves with SF were determined for violets cultivated in pots containing substrate. In the last, criteria to define nutrient recovery rates in plants and substrate chemical extraction were determined. Finally, the proposed experimental technique is presented.

Leite F.P.,Celulose Nipo Brasileira S.A. CENIBRA | Novais R.F.,Federal University of Viçosa | Silva I.R.,Federal University of Viçosa | Barros N.F.,DPS UFV | And 4 more authors.
Revista Brasileira de Ciencia do Solo | Year: 2014

Eucalyptus Shoot Blight in the Vale do Rio Doce (ESBVRD) is an anomaly that leads to reduced growth and, in more extreme cases, to death of eucalyptus plants. Initially diagnosed in plantations in the region of the Vale do Rio Doce, in the State of Minas Gerais, Brazil, this problem has also been found in plantations in other regions of the country and even in other countries. Although the symptoms of this anomaly are well-known, its causes are not yet understood. The aim of this study was to evaluate the cause-effect relationship between accumulation of manganese (Mn) in eucalyptus clones and ESBVRD. Characterization of the environment in areas of greater occurrence of this problem in regard to soil, climate and fluctuation of the water table was undertaken in eucalyptus plantations of the Celulose Nipobrasileira S.A. (Cenibra) company in the region of the Vale do Rio Doce. Plant tissues were sampled in two situations. In the first situation, diagnosis occurred in the initial phase of the anomaly in clones with differentiated tolerance to the problem; in the second situation, diagnosis was made in a single clone, considered to be sensitive, in two time periods - in the phase with the strong presence of symptoms and in the recovery phase, in areas of occurrence and in areas of escape from the problem. The most ESBVRD-sensitive clone showed much higher (4.8 times higher) leaf Mn contents than more tolerant clones. In plants with the anomaly, Mn leaf contents were greater than 3,070 mg kg-1, much greater than the quantity found in those without the anomaly (734 mg kg-1). In the period in which the symptoms began to wane, there was a sharp decline in leaf Mn contents, from 2,194 to 847 mg kg-1. Manganese content in the above ground part and plant litter (44.4 g ha-1) in the area of occurrence of the anomaly was three times greater than that found in these same components (14.1 g ha-1) in the area of absence of the symptom. Based on the evidence found, such as the existence of environmental conditions favorable to high Mn availability to the plants in the areas of greatest incidence of ESBVRD, greater uptake of Mn in sensitive clones and in plants with symptoms, and a synchronism between the intensity of symptoms of ESBVRD and leaf Mn contents, it may be inferred that temporary excess of Mn in eucalyptus plants is closely related to ESBVRD.

Lo Monaco P.A.V.,Federal University of Viçosa | De Matos A.T.,DPS UFV | Andrade Ribeiro I.C.,Federal University of Viçosa | Da Silva Batista A.P.,Federal University of Viçosa | And 2 more authors.
Revista Caatinga | Year: 2014

The use of natural coagulants and organic filters locally produced and low financial cost can provide attenuation problems in discharge of wastewaters, without treatment, into watercourses. Was evaluated in this study the efficiency of the coagulation process, using the Ca(OH)2 in the preparation of Moringa seed extract, followed by filtration sawdust in the treatment of sewage. In the tank of 150 L containing sewage was added a solution of the moringa seed extract prepared with Ca(OH)2 0.011 mol L-1 at a concentration of 2.2 grams of seed per liter of wastewater to be treated. The coagulated effluent was applied to organic filter and the filtrate volume was converted in pore volume. Physical and chemical analyses were carried out in the influent and effluent of the two treatment structure for the evaluation of treatment efficiency. The treatments by coagulation followed by filtration provided removals of 98.0, 75.3, 75.8, 75.0, 79, 7, 59.0 and 88.3% of turbidity, Total Solids, Total Fixed Solids, Total Volatile Solids, Total Suspended Solids, Suspended Solids Fixed and Volatile Suspended Solids and of 51.2, 88.7, 72.6; 33.5 and 38.5% of Biochemical Oxygen Demand, Chemical Oxygen Demand, Phosphorus, Nitrogen and Sodium.

Cunha J.C.,Federal University of Pernambuco | Ruiz H.A.,Federal University of Espirito Santo | Freire M.B.G.S.,Federal Rural University of Pernambuco | Alvarez V. V.H.,Federal University of Viçosa | Fernandes R.B.A.,DPS UFV
Revista Brasileira de Ciencia do Solo | Year: 2014

The electrical charges in soil particles are divided into structural or permanent charges and variable charges. Permanent charges develop on the soil particle surface by isomorphic substitution. Variable charges arise from dissociation and association of protons (H+), protonation or deprotonation, and specific adsorption of cations and anions. The aim of this study was to quantify the permanent charges and variable charges of Reference Soils of the State of Pernambuco, Brazil. To do so, 24 subsurface profiles from different regions (nine in the Zona da Mata, eight in the Agreste, and seven in the Sertão) were sampled, representing approximately 80% of the total area of the state. Measurements were performed using cesium chloride solution. Determination was made of the permanent charges and the charges in regard to the hydroxyl functional groups through selective ion exchange of Cs+ by Li+ and Cs+ by NH4 +, respectively. All the soils analyzed exhibited variable cation exchange capacity, with proportions from 0.16 to 0.60 and an average of 0.40 when related to total cation exchange capacity. © 2014 Revista Brasileira de Ciencia do Solo. All rights reserved.

Vasconcelos B.N.F.,DPS UFV | Ker J.C.,Federal University of Viçosa | Schaefer C.E.G.R.,Federal University of Viçosa | Poirier A.P.P.,Federal University of Minas Gerais | Andrade F.V.,Federal University of Espirito Santo
Revista Brasileira de Ciencia do Solo | Year: 2013

The occupation and territorial dispersion of the first settlers in South America, especially in Brazil, are still little known and require continuous interdisciplinary studies involving anthropology, archeology, and soil science. Under natural limestone shelters, pre-Columbian populations lived for thousands of years, introducing and removing materials of different nature and from different origins, resulting in the development of very peculiar anthropogenic soils, which have been little investigated so far. To deepen the knowledge on this type of soil, we evaluated the physical, chemical and mineralogical properties of the soil of two limestone shelters, Lapa do Boquete and do Malhador, located in the National Park Cavernas do Peruaçu, in northern Minas Gerais, which is considered one of the most important archaeological regions of the country. The samples were subjected to the physical, chemical and mineralogical analyses, total attack, total organic carbon, and fractionation of inorganic P forms. The chemical properties of these soils are consistent with the calcareous nature of the local rock, with high pH values (> 7.7). The cation exchange complex consists almost entirely of exchangeable bases, especially Ca and Mg, reaching V valuesof 100 %. High P contents (131-749 mg dm-3) were also extracted (Mehlich-1). The predominant soil fraction was sand, with a loamy texture in all layers. The presence of oxides with magnetic attraction in all fractions is noteworthy, especially in the sand fraction, mainly associated with the carbonized layers. The soil matrix is made predominantly by 1:1 silicate minerals (kaolinite) associated with 2:1 minerals, mainly illite. According to the results, soil genesis is polycyclic, marked by pronounced climate changes, and associated with distinct periods of human occupation, resulting in the formation of pedogenetic layers that seem unrelated with each other.

Paes J.L.A.,DPS UFV | Ruiz H.A.,Alto Universitario | Fernandes R.B.A.,DPS UFV | Freire M.B.G.S.,Federal Rural University of Pernambuco | And 2 more authors.
Revista Brasileira de Engenharia Agricola e Ambiental | Year: 2013

To estimate clay dispersion the water dispersible clay is determined in the laboratory. This analysis may not correspond to reality in saline and saline-sodic soils, with high concentrations of salts in the solution. In this context, the dispersed clay was determined, using solutions of different electrical conductivities (0; 0.3; 0.6; 0.9 and 1.2 dS m-1) in seven representative soils of the State of Pernambuco, with the exchangeable-sodium-percentage adjusted in the range of 5-30%. The results showed that there was an increase of dispersed clay directly related to the increase in the exchangeable sodium percentage and the decrease of the electrical conductivity of the solution. The response to treatments was more pronounced in soils with higher proportions of more active clays compared to those with more iron oxides. The determinations of the water dispersible clay are accomplished with deionized or distilled water. However, in soils affected by salts, it is concluded that the determinations should be carried out with solutions of electrical conductivity different from 0 dS m-1 using solutions with values similar to those determined in the saturation extract.

Costa S.A.D.,DPS UFV | Ker J.C.,DPS UFV | Simoes D.F.F.,University of Pernambuco | Fontes M.P.F.,DPS UFV | And 2 more authors.
Revista Brasileira de Ciencia do Solo | Year: 2014

Located in the Midwest of the State of Minas Gerais, a region called Quadrilátero Ferrífero covers an area of approximately 7,000 km2. Since the seventeenth century, it is known as goldand iron-producing province, and the geological context is therefore one of the best-studied of Brazil. The regional topography is very rugged, with mostly poorly developed pedogenesis, especially Cambissolos Háplicos, Neossolos Litólicos and Neossolos Regolíticos. In a smaller proportion and on colluvial ramps (hilly relief), very Fe-rich Latossolos Vermelhos occur, formerly Latossolos Ferríferos. This study characterized the physical, chemical and mineralogical properties of samples from nine ferric and hyperferric Latossolo Vermelho profiles, developed from itabirite and related rocks in the Quadrilátero Ferrífero, with the objectives of improving the understanding of their genesis and establish taxonomic criteria for their differentiation in the SiBCS at lower categorical levels. The high particle density values in these soils are peculiar and along with the strong, very small and granular structure, are factors that contribute to underestimate clay and overestimate silt, resulting in a higher silt/clay ratio than proposed by SiBCS for Latossolos. Variations in the levels of SiO2, Fe2O3, Al2O3, TiO2, MnO, P2O5, and of some trace elements indicate the diversity in the chemical composition of itabirite or a probable mixture with phyllitic rocks of the region. The ratios of Fe2O3/TiO2 (non-molecular) and TiO2/Fe2O3 (molecular) reported in the literature for separation of Latossolos Vermelhos differed between soils developed from itabirite and from mafic rocks. The magnetic attraction in sand, silt and clay varied greatly; due to the presence of magnetite, magnetization was higher in the former two fractions. The values of isomorphic Al-for-Fe substitution ranged from 0.07 to 0.11 and from 0.09 to 0.38 mol mol-1 in the structures of hematite and magnetite, respectively.

Chagas C.S.,Rua Jardim Botanico | Fernandes Filho E.I.,DPS UFV | Rocha M.F.,Federal Rural University of Rio de Janeiro
Revista Brasileira de Engenharia Agricola e Ambiental | Year: 2010

In Brazil, the digital elevation models (DEMs) are usually produced by users themselves and little attention has been given to their limitations as source of spatial information. The objective of this study was to evaluate different DEMs to help in choosing an appropriate model to derive topographical attributes used in a digital soil mapping based on a neural networks approach. The evaluation consisted of the following analysis: determination of root mean square error (RMSE) of elevation; analysis of the spurious depressions; comparison between mapped drainage and numeric drainage and between derived contour lines and original contour lines; and analysis of the derived contribution basins. The results demonstrated that RMSE was not enough to evaluate the quality of these models. DEMs derived from contour lines (CARTA, obtained using the TOPOGRID module) presented better quality than those derived from remote sensors (ASTER and SRTM). These presented great amount of errors that can negatively affect the establishment of relationships between topographical attributes and local conditions of soils.

Oliveira D.M.S.,University of Sao Paulo | De Lima R.P.,University of Sao Paulo | Verburg E.E.J.,DPS UFV
Revista Brasileira de Engenharia Agricola e Ambiental | Year: 2015

The application in agriculture has been the main alternative to allocate the large volume of pig slurry (PS) generated in production environments. The aim of this study was to assess possible changes in physical properties of soil resulting from the management system and PS application. Five areas were sampled: native forest, pasture with mineral fertilizer and PS application, conventional tillage with mineral fertilizer and PS application, no-tillage with mineral fertilizer, no-tillage with mineral fertilizer and PS application. The evaluated physical properties of soil were: bulk density (Bd), total porosity (Pt), macroporosity (Ma), macro and microporosity ratio (Ma/Mi) and penetration resistance (PR). The adoption of different agricultural management systems altered the physical conditions of the soil, increasing the Bd and the PR and reducing the pore volume. The soil managed under pasture showed the highest values of PR. No changes were found in physical properties of soil by the application of PS in evaluated tillage systems. © 2015, Departamento de Engenharia Agricola - UFCG/Cnpq. All rights reserved.

Cunha J.C.,Federal Rural University of Pernambuco | Freire M.B.G.S.,Federal Rural University of Pernambuco | Ruiz H.A.,Brazilian National Council for Scientific and Technological Development | Fernandes R.B.A.,Brazilian National Council for Scientific and Technological Development | Alvarez V. V.H.,DPS UFV
Revista Brasileira de Engenharia Agricola e Ambiental | Year: 2014

Laboratories in different regions of Brazil do not standardize the procedures for particle size analysis. Solutions of sodium hydroxide (NaOH), sodium hexametaphosphate and sodium carbonate [(NaPO3)n + Na2CO3] are the most commonly used in the chemical dispersion of the particle of soil. Te high pH of the NaOH solution favors the dispersion in soils with clay minerals of variable-charge in the clay fraction, as oxides of iron and aluminum present in tropical soils. Based on this statement it was aimed to test the efficiency of NaOH (D1), [(NaPO3)n + Na2CO3] (D2) and [(NaPO3)n + NaOH] (D3) solutions as chemical dispersants in the particle-size analysis of two horizons of 26 reference soils of the State of Pernambuco. Te comparison between the dispersants was performed using the statistics test L&O. Te comparison of D2 = f (D1) and D3 = f (D1) showed no agreement between the dispersants. Te intercept in the linear regression equation for the clay fraction, significant at 0.01 and negative, showed highest clay values when using D1. Te NaOH solution was the most suitable dispersant to determine the texture of the analysed samples, representative of 82% of the total area of the state.

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