Acúmulo de nutrientes e decomposição do palhiço de cana em função de doses de vinhaça

Understanding the influence of vinasse application on trash decomposition and its effects on soil chemical attributes and sugar cane culture is essential for the good management of the production system. The objective of this study was to assess the time of decomposition and nutrient cycling of the green ratoon cane's trash, and their effects on soil fertility and technological components of crops, in terms of vinasse doses. The study was developed in the northwest region of Sao Paulo State - Brazil, under Eutrophic Ultisol, using the RB855453 variety. The experimental design was randomized blocks with split plot in time. The treatments were composed of four doses of vinasse (0, 50, 100 and 200 m(3) ha(-1)). There was a 20.9% reduction in the amount of crop residue remaining after one year review. The vinasse doses increased the ratoon cane's yield, without interfering in the raw material quality. The green cane system, in which the trash is deposited on the soil and vinasse application, changes the dynamics of the trash decomposition and modifies the soil fertility, contributing positively to the crop yield.

Distribuição natural de espécies arbóreas em áreas com diferentes níveis de antropização e relação com os atributos químicos do solo

With the emergence of areas degraded by human activities, the chemical soil properties and silvicultural characters became important in understanding the succession process of tree species and planning of landscape restoration. This study aimed to evaluate the distribution of tree species in areas with different levels of human disturbance, relating silvicultural aspects to the soil chemical properties and characterizing the type of vegetation, for integration of genetic conservation program in situ. The study was conducted in the area of Research and Extension Experimental Farm (FEPE) from UNESP, Ilha Solteira, in Selviria - MS. Through transect, 64 plots were marked 50 m equidistant with dimensions of 10 x 10 m, where: 29 plots were in an highly disturbed area (HDA), five in moderately disturbed area (MDA), 15 in lowly disturbed area (LDA), six in riparian stream of Vestia river (Riparian Forest) and nine in the legal reserve. Soil samples were collected at two depths (0.0 to 0.20 and 0.20 to 0.40 m) for the chemical analysis and the assessment of silvicultural characters, such as height, diameter at breast height (DBH) and shape. The study of the natural distribution of tree species and edaphic condition in the different evaluated areas showed that: the soil chemical properties associated with the level of human disturbance and conservation of the areas are influencing the natural occurrence, species diversity and development of the trees. Height, DBH and shape are good indicators to assess the growth of the tree community and relate them to soil chemical properties; LDA and legal reserve presented higher natural occurrence, number of individuals and number of species. In the riparian forest, basal area values, height, shape and chemical soil properties were higher. From the 97 species found, six have the potential to be used in a program of genetic conservation in situ. They are: Astronium fraxinifolium, Terminalia argentea, Curatella americana, Cupania vernalis, Qualea jundiahy and Andira cuyabensis.

Mapeamento do fósforo adsorvido por meio da cor e da suscetibilidade magnética do solo

The objective of this work was to evaluate the possibility of mapping adsorbed phosphorus through soil color and magnetic susceptibility. The experiment was done in a 380-ha sugarcane area, which included four types of Oxisols, with different texture and natural fertility. Two hundred and forty-one soil samples were collected at 0.00-0.25-m depth. The soil redness index was calculated from sample values of hue, value, and chroma, obtained with diffuse reflectance spectroscopy. Regression models were adjusted between adsorbed phosphorus and soil magnetic susceptibility or redness index. Data spatial dependence was evaluated with geostatistics. Magnetic susceptibility is significantly correlated to adsorbed phosphorus, which allows it to be used as a component in pedotransfer functions for indirect quantification of soil adsorbed phosphorus. The redness index and the magnetic susceptibility show spatial dependency with adsorbed phosphorus. Soil magnetic susceptibility and redness index, evaluated with diffuse reflectance spectroscopy, can aid in the mapping and identification of areas with different phosphorus adsorption potential.

Liming in Growing Mango Cultivar Keitt in Production

The tropical soil acidity is one of the main limiting factors for crop productivity. This study aimed to evaluate the effects of application of limestone dose to soil fertility, nutritional status of the crop, and productivity and quality of the fruits of mango, cultivar Keitt. The study was carried out at Selviria, state of Mato Grosso Sul, Brazil, in a Typic Haplustox (pH in CaCl2=4.7), cultivated with mango cultivar Keitt grafted on Coquinho pattern in the production phase (13years old). Treatments were composed of limestone doses (0, 1.55, 3.10, 4.65, and 6.20tha(-1)), arranged in blocks at random with three repetitions. The limestone was applied and incorporated in the surface layer of 0 to 5cm deep in the total area. We evaluated the chemical attributes of the soil [pH, hydrogen (H+) aluminum (Al), calcium (Ca), magnesium (Mg), potassium (K), and sum of bases and base saturation] at 16 and 28months after liming (layer 0 to 20cm deep), the nutrition of plants at 12months after liming, and quality of the fruit in two crop years. Liming promoted improvements in soil chemical attributes, reflected in the nutritional status, productivity, and quality of mango fruit. Also, there was a linear effect with the application of lime dose on the productivity of the fruit, but after the second year of evaluation.

Quality of wood and pulp from a clone of Eucalyptus grandis planted at three locations

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

Atributos químicos e físicos de um argissolo cultivado com Panicum maximum Jacq. cv. IPR-86 Milênio, sob lotação rotacionada e adubado com nitrogênio

A avaliação dos atributos químicos e físicos do solo é necessária em estudos que exploram intensivamente os sistemas de pastejo. No presente trabalho, objetivou-se avaliar as variações nos atributos físicos e químicos de um Argissolo cultivado com capim-milênio, sob pastejo, no intervalo compreendido entre outubro/2001 e maio/2002, no quinto ano de aplicação sucessiva das seguintes doses de N: 0, 150, 300 e 450 kg ha-1. Após os cinco anos de aplicação de 450 kg ha-1 de N, o teor de MO aumentou em 5 g dm-3, o que resultou em aumento da CTC. No período de outubro/2001 a maio/2002 houve diminuição nos valores de pH e de V com a aplicação de N. A densidade do solo variou pouco com a adubação nitrogenada; a percentagem de microporos aumentou e a de macroporos diminuiu na camada de 0-5 cm com o aumento das doses de N, mas a porosidade total permaneceu constante; e a resistência à penetração, quando o solo apresentava 90 g kg-1 de água, não foi afetada pelas doses de N e não foi restritiva ao crescimento das plantas.

Efeitos da disposição de lodo de ETE de indústria alimentícia no solo: estudo de caso

Pós-graduação em Geociências e Meio Ambiente - IGCE

Atributos químicos, bioquímicos e microbiológicos em solos com 18 anos de aplicações anuais de lodo de esgoto

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Ciclagem de carbono em área sob semeadura direta e aplicação de lodo de esgoto

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Avaliação de um sensor de resistencia eletrica e sua correlação com atributos do solo

The electrical measures of the soil have been used as variables that correlate with its characteristics. This study aimed at developing an electrical capacitance sensor of low cost, to evaluate its performance on the field and verify the correlation between the measurements of electrical capacitance with physical properties (sand, silt and clay) and chemical properties of soil (pH, MO, P resin, H + Al, K, Ca, Mg, SB, CTC and V%) and the moisture content. The data sampling was performed at the farm named "Capão da Onça" which belongs to the State University of Ponta Grossa. The samples collection was conducted in an area of approximately 13 hectares, totalizing 81 samples. In each sampling the electrical capacitance of the soil was measured. After the sensor withdrawal, soil samples were collected and sent to be analysed in the laboratory of the College of Agronomics Science of the Paulista State University. The measuring instrument used to collect data on electric capacitance of the soil a digital multimeter was used. The data were submitted to the analysis of correlation and regression. The developed system presented a low cost and it was capable to measuring variation of the electrical capacitance of the soil. The obtained measures satisfactorily correlated with the levels of clay and sand, and weakly with the moisture content. This had demonstrated the possibility to use a sensor to verify the soil texture in not homogeneous areas. The measures of the electrical capacitance of the soil obtained by the sensor had significantly correlated with the soil attributes: calcium, magnesium, pH, SB and CTC. These results had demonstrated the possibility to use a sensor for soil fertility control.

Desempenho agronômico do lodo de esgoto como fonte de nitrogênio em bananeiras

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Emissão de gases de efeito estufa e estoque de carbono no solo em função do manejo e correção de acidez

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

Comportamento do carbono orgânico e de atributos químicos, físicos e microbiológicos de um solo arenoso em área de conversão pastagem - Eucalipto

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Soil uses in the sugarcane fallow period to improve chemical and physical properties of two latosols (oxisols)

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

Nutrient recycling and physical indicators of an alley cropping system in a sandy loam soil in the pre-Amazon region of Brazil

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)