Aplicação da metodologia de superfície de resposta na remediação de um solo arenoso contaminado artificialmente com cobre

Soil flushing is an alternative remediation technology for soils contaminated with heavy metals, which the main contaminant removing process consists in percolating an extraction solution. This work aimed to use the response surface methodology to point out combinations among the parameters of the extraction solution (Na2EDTA concentration, volume e pH) in order to reduce the concentration of copper in a sandy soil to risk levels lower than the intervention levels for exposure scenarios adopted by the Environmental Company of Sao Paulo State. Thus, a series of tests in leaching columns were carried out using a Fluvisol artificially contaminated (1257,3 mg kg-1). The tests were conducted in triplicate and setup a central composite rotatable design with 15 different parameters combinations of the extraction solution and one replicate in the center point. Using 5% significance level, the adjusted model (R2 = 0,98) indicated combinations of Na2EDTA concentration, pH and volume of the extraction solution which allow reduction of copper concentration below levels reported by environmental agency of Sao Paulo State for industrial, residential, agricultural or maximum exposure scenarios.

Métodos de interpolação para estimar o ph em solo sob dois manejos de café Arábica

There are many methods used to estimate values in places no sampled for construction of contours maps. The aim of this study was to use the methods of interpolation kriging, inverse of the square of the distance and polynomial in the representation of the spatial variability of the pH of the soil in the organic and conventional management in the culture of the coffee plantation. For that, irregular meshes were built for soil sampling in the depth of 0-0,10 meters, totaling 40 points sampling in each area. For gauging of the interpolation methods they were solitary 10% of the total of points, for each area. Initially, the data were appraised through the classic statistics (descriptive and exploratory) and spatial analysis. The method inverse square of the distance and kriging has low error in estimating dados. The method of kriging presented low variation around the average in different managements.

Desempenho de semeadora-adubadora em função do prepa ro de solo e espa çamento da cultura do milho

The performance of machines and agricultural implements are of fundamental importance, especially when subjected to different types of soil tillage, and have to adapt to these conditions, in order to promote good operational performance. The objective of this study was to analyze the operational performance of a Marchesan Supreme Cop grain drill, equipped with four rows, spaced 0.90 m, according to three types of tillage: conventional tillage (plowing and two harrowing series), reduced tillage (scarification with a roller), and no-tillage, in areas previously seeded with maize (Zea mays L.), at two spacing measures (0.90 m and 0.45 m). The results indicate that the demand for power, tensile stress, and motor rotation, in the sowing operation, were not influenced by tillage and maize crop. The tractor wheel slip showed different results, being lower in no-tillage and higher in conventional and reduced tillage.

Atributos químicos do solo e produtividade da cultura de soja em área de semeadura direta após calagem superficial

This study was carried out to evaluate the effects of surface application of lime rates on soil chemical attributes and soybean yield in a no-tillage system. It was installed a field experiment in a factorial 2×4, and the factors were: two types of lime (calcitic and dolomitic); four rates (0.0 - 0.5 - 1.0 and 1.5 t ha-1 of CaCO3), in a completely randomized blocks experimental design, with four replications. The experiment was located in Matupá, Mato Grosso State, Brazil, being the work developed between November 2006 and May 2007. The evaluations were chemical attributes in the soil layers (0,0-2,5 cm, 2,5-5,0 cm and 5,0-10,0 cm), and the productive characteristics of soybean. Application of lime increased the soil pH (CaCl 2), the exchangeable Ca and Mg, the effective CEC and the base saturation only in the soil surface layer. The two limes were different only for Ca and Mg values in the first layer of soil, and only for the Mg values in the layer of 2,5-5,0 cm. The surface liming in no-tillage system did not change soybean yield.

Influência da aplicação de vinhaça na capacidade de Infiltração de um solo de textura franco arenosa

The objective of this study was to analyze effects in different depth in soil water infiltration and to verify the Horton and Kostiakov-Lewis models adequacy in infiltration rate estimate. The treatments were five doses of vinasse (0, 200, 250, 300 and 350 m3?ha1?. The vinasse application reduced the soil erosion risk increasing the possibility of runoff. The Horton model had the best adjustment on the observed data, and the Kostiakov-Lewis model overestimated the infiltration rate values.

Variabilidade espacial de atributos químicos do solo cultivado com café arábica (Coffea arabica L.) sob diferentes manejos

The objective of this work was to assess the spatial variability of the chemical attributes of two coffee areas, managed in conventional and organic crop systems, and to calculate the percent of variation between them. In each area, a 40-point-mesh was sampled at 0-0.10 m and 0.10-0.20 m layers, within the crown projection, for pH, SB, K, P, Ca and Mg analysis. The data were analyzed through descriptive statistics and geostatistics. From the soil chemical attributes map, the percent of variation between the systems' chemical attributes was determined by GIS algebraic operations. The results show that the soil chemical attributes present a spatial dependence in both systems and layers. Analysis of the soil chemical attributes showed less spatial variability in the organic system, in relation to the conventional, indicating homogeneous zones for different fertilizer applications. The percent of variation of the chemical attributes in the conventional system, in relation to the organic, at 0-0.10 m and 0.10-0.20m layers are 54.80% and 35.61%, respectively.

Determinação da massa seca, teor de nutrientes e cobertura do solo de espécies semeadas no outono-inverno

Culture options for the autumn-winter season are a major problem for production systems under low rainfall. The aim of this study was to evaluate the effect of the sowing season on dry matter yield, nutrient content of the shoot and soil covering percentage of coverage plants on the soil on the intercrop: grain sorghum, rattlepods, pearl millet brachiaria grass and an area with weeds (fallow). The experiment was conducted under field conditions on an Oxisol (Haplustox), clay texture, in Selvíria, Mato Grosso do Sul, Brazil. The experimental design was a randomized block design with eight replications, two sowing seasons and five coverage treatments. When the sorghum culture of the first sowing season reached the harvest stage, the dry matter yield on the other treatments was evaluated. Results showed that sowing in March results in higher dry mass yield and higher soil coverage percentage in the studied species. In the first sowing season, Brachiaria brizantha presents higher dry matter yield and macronutrients extraction.

Carbono orgânico e carbono residual do solo em sistema de plantio direto, submetido a diferentes manejos

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Atributos químicos do solo sob plantio direto afetado por sistemas de culturas e fontes de adubação

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Análise temporal do uso do solo e comparação entre os índices de vegetação ndvi e savi no município de Santa Cruz do Rio Pardo - SP usando imagens landsat-5

This work aims to analyze the land use evolution in the city of Santa Cruz do Rio Pardo - SP through supervised classification of Landsat-5 TM satellite images according to the maximum likelihood (Maxlike), as well as verifying the mapping accuracy through Kappa index, comparing NDVI and SAVI vegetation indexes in different adjustment factors for the canopy substrate and determining the vegetal coverage percentage in all methods used on 2007, May 26 th; 2009, January 7 th and 2009, April 29 th. The Maxlike classification showed several spatial changes in land use over the study period. The most appropriated vegetation indexes were NDVI and SAVI - 0,25 factor, which showed similar values of vegetal coverage percentage, but discrepant from the inferred value for Maxlike classification.

Avaliação das propriedades químicas em solo de cerrado SOB reflorestamento ciliar

The rapid growth of agriculture, promoted by public government initiatives, favored an out of control deforestation of our forests; today, reforestation of permanent preservation areas are necessary for the conservation of our natural resources, and recovery of such areas are required by public laws. In an area of 5.26 acres of riparian reforestation in the savanna soil chemical properties were evaluated after twenty years of planting. It was analyzed the following variables: (P, organic matter (MO), pH, K, Ca, Mg, H+Al, Al and S) in 13 modules, with three replicas in two depths (0 - 20 and 20 - 40 cm) in a randomized block design in hierarchical scheme. Reforestation with tree species on the edge of Parana river in Selvíria (MS) contributes to chemical soil attributes, under riparian reforestation, as similar as a soil without human disturbance in this region; it is also possible to verify that forestry plantation promotes deposition of organic material which is essential for nutrient cycling, which keep the chemical properties of such soil in good condition for the establishment of riparian vegetation.

Influência de diferentes sistemas de cultivo nos atributos físicos e no carbono orgânico do solo

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Atributos físicos do solo em diferentes condições de cobertura vegetal em área de plantio direto

The use of cover crops in the soil causes changes in soil attributes influencing in a series of hydro-physical processes, which also modify the ability of soil to support the many activities that it is intended. Thus, the objective of this study was to evaluate the effect of cover crops on physical attributes of the soil. For this, an experiment was carried out on a Typic Hapludox, Jaboticabal State, Brazil, using cover crops of millet, sunn hemp, jack bean, lab-lab and black velvet bean in no-tillage and fallow area (spontaneous vegetation). The characteristics evaluated were the bulk density, macroporosity, microporosity, total porosity, aggregate stability, penetration resistance and organic matter. The incorporation of cover crops has proved to be a beneficial practice for the physical attributes of the soil, allowing a greater aggregate stability compared to fallow in the depth of 0-0.05 m. All cover crops presented values of soil penetration resistance below the critical value of 2 MPa.

produção de mudas de maracujazeiro amarelo submetidas à salinidade em solo com biofertilizante bovino

The experiment was conducted in a greenhouse from May 1 to July 31, 2008, in Areia county, Paraiba State, PB, Brazil, in order to evaluate the effects of irrigation water salinity on initial growth of the passionfruit seedlings in non-saline substrate with and without bovine biofertilizer. The treatments were distributed in a completely randomized design, with three replications and twelve plants per plots, in a factorial arrangement 5 × 2 × 2, corresponding the former to the levels of salinity in the irrigation water: 0.5; 1.0; 2.0; 3.0 and 4.0 dS m-1, in soils with and without bovine biofertilizer applied at two moments (25 and 65 days after seedling emergence). The growth of the seedlings and the soil electrical conductivity were evaluated at the end of the experiment. The biofertilizer was diluted in a low saline water at a 1:1 ratio and was applied once two days before sowing, corresponding to 10% of the substrates volume. The increase in water salinity inhibited the growth in height of plants, leaf area and root length, but always to a lesser extent in the treatments with bovine biofertilizer. The increase in electrical conductivity of the irrigation water elevated the soil salinity, independently of the addition of biofertilizer.

Uso de Dois Espaçamentos Entre Gotejadores na Mesma Linha Lateral e Seus Efeitos Sobre a Formação do Bulbo Molhado no Solo e Parâmetros Físicos de Rabanete

The use of irrigation systems that consume lower water and energy in agriculture is important to supply the growing global demand for food. In this way, it's important to develop techniques that will increase the uniformity of water application on drip irrigation systems. The aim of the work was to compare the provision of lateral lines in drip irrigation, through the formation of wet bulbs in soil and physical parameters of radish, composed of single spacing between drippers in relation to lateral lines composed of two segments, each one composed by different spacing between emitters. Two distributions of evaluation were carried out: 1) conventional drip lateral lines with 20 cm emitter spacing were compared to proposed drip lines, with 24 emitter spacing in the initial section and 20 cm emitter spacing in the final section; 2) conventional drip lateral lines with 30 cm emitter spacing were compared to proposed drip lines, with 36 emitter spacing in the initial section and 30 cm emitter spacing in the final section. The experiment was carried out in a greenhouse of the Sao Manuel Experimental Farm, located at Sao Manuel, SP. The experimental design was entirely randomized, with six treatments and four replications. Results showed no difference among treatments for the most of the evaluated variables. So it is possible to conclude that the use of different spacing between emitters in the same lateral line can be used to increase the line length.