3290 results

Growth of seedlings of pigeon pea (Cajanus cajan (l.) millsp), wand riverhemp (Sesbania virgata (cav.) pers.), and lead tree (Leucaena leucocephala (lam.) de wit) in an arsenic-contaminated soil

Luiz Eduardo Dias, Roseli Freire Melo, Jaime Wilson Vargas de Mello, Juraci Alves Oliveira, Walter Lee Daniels

01/Jun/2010

Phytoremediation strategies utilize plants to decontaminate or immobilize soil pollutants. Among soil pollutants, metalloid As is considered a primary concern as a toxic element to organisms. Arsenic concentrations in the soil result from anthropogenic activities such as: the use of pesticides (herbicides and fungicides); some fertilizers; Au, Pb, Cu and Ni mining; Fe and steel production; coal combustion; and as a bi-product during natural gas extraction. This study evaluated the potential of pigeon pea (Cajanus cajan), wand riverhemp (Sesbania virgata), […]

Performance and environmental impact of antibiotics in animal production in Brazil

Jussara Borges Regitano, Rafael Marques Pereira Leal

01/Jun/2010

Antibiotics are used in large quantities in livestock. Many of these molecules are not fully metabolized by the animals, leaving detectable residues in soil, surface water and groundwater samples. The occurrence of these residues in the environment can favor microorganism resistance to antibiotic agents, in addition to toxic effects on certain living organisms. In general, veterinary antibiotic molecules are amphoteric with many ionizable functional groups (different pKa values), rather variable molar masses (172 to 916 g mol-1) and low volatilization potential (vapor […]

Distribution of 137Cs in three representative soils of pernambuco state, Brazil

Patrik Diogo Antunes, Everardo Valadares de Sá Barretto Sampaio, Antônio Luiz Gonçalves Ferreira Júnior, Izabel Cristina Luna Galindo, Ignácio Hernan Salcedo

01/Jun/2010

Contents of 137Cs have been used to quantify soil loss or accumulations, based on values of reference sites with little soil disturbance in the last decades. In Northeastern Brazil no such sites have been evaluated yet. Three areas with flat topography, native vegetation and undisturbed soil were selected in of Goiana, Araripina and Sertânia counties, state of Pernambuco. Four points in each area were marked at a distance of 20 to 50 m away from each other and soil samples were […]

Limits of consistency chemical properties of a dystrophic cohesive yellow latosol under different sugarcane residues

Romero Falcão Bezerra de Vasconcelos, José Ramon Barros Cantalice, Apolino José Nogueira da Silva, Veronildo Souza de Oliveira, Yuri Jacques Agra Bezerra da Silva

01/Jun/2010

The physical and chemical properties of coastal plain soils cultivated with sugarcane for a long period under different management systems may undergo changes. The objective of this study was to evaluate the effects of different sugarcane management systems on the chemical and physical properties of a dystrophic cohesive Yellow Latosol of coastal tablelands in the state of Alagoas. Three experimental plots were selected in sugarcane growing areas, representing the three management systems used for ethanol production, namely: a cultivated area […]

Molecular analysis of the bacterial diversity in a specialized consortium for diesel oil degradation

Douglas Antonio Alvaredo Paixão, Mauricio Rocha Dimitrov, Rodrigo Matheus Pereira, Fábio Raphael Accorsini, Maria Benincasa Vidotti, Eliana Gertrudes de Macedo Lemos

01/Jun/2010

Diesel oil is a compound derived from petroleum, consisting primarily of hydrocarbons. Poor conditions in transportation and storage of this product can contribute significantly to accidental spills causing serious ecological problems in soil and water and affecting the diversity of the microbial environment. The cloning and sequencing of the 16S rRNA gene is one of the molecular techniques that allows estimation and comparison of the microbial diversity in different environmental samples. The aim of this work was to estimate the diversity […]

Availability of soil water under tillage systems, mulch management and citrus rootstocks

Jonez Fidalski, Pedro Antonio Martins Auler, José Marcos Garrido Beraldo, Celso Jamil Marur, Rogério Teixeira de Faria, Graziela Moraes de Cesare Barbosa

01/Jun/2010

The increased availability of soil water is important for the management of non-irrigated orange orchards. The objective of this study was to evaluate the availability of soil water in a Haplorthox (Rhodic Ferralsol) under different tillage systems used for orchard plantation, mulch management and rootstocks in a “Pêra” orange orchard in northwest Paraná, Brazil. An experiment in a split-split-plot design was established in 2002, in an area cultivated with Brachiaria brizantha grass in which three tillage systems (no tillage, conventional […]

Spatial variability of physical attributes of an alfisol under different hillslope curvatures

Livia Arantes Camargo, José Marques Júnior, Gener Tadeu Pereira

01/Jun/2010

The influence of relief forms has been studied by several authors and explains the variability in the soil attributes of a landscape. Soil physical attributes depend on relief forms, and their assessment is important in mechanized agricultural systems, such as of sugarcane. This study aimed to characterize the spatial variability in the physical soil attributes and their relationship to the hillslope curvatures in an Alfisol developed from sandstone and growing sugarcane. Grids of 100 x 100 m were delimited in a convex and […]

Potassium-rich silicate rocks as plant nutrient sources

Luciano da Silva Ribeiro, Anacleto Ranulfo dos Santos, Luiz Francisco da Silva Souza, Jamile Santana Souza

01/Jun/2010

This greenhouse study evaluated the effect of potassium-rich silicate rocks (alkaline ultramaphic, pyroclastic breccia and phlogopite) on the release of K and other chemical nutrients of the soil. A Yellow Latossol with 0.03 cmolc dm-3 K soil was used in the study. The rocks were tested at doses of 75, 150, 225 and 300 kg ha-1 K2O with and without lime, applied to increase the soil base saturation (V-value) to 70 %. The rock and lime materials were mixed with the soil in the pots, […]

Soil shear strength under non-irrigated and irrigated short duration grazing systems

Rita de Cássia Ribeiro Carvalho, Wellington Willian Rocha, José Cardoso Pinto, Bruno da Silva Pires, Moacir de Souza Dias Junior, Ayeska Hubner Braga Nunes

01/Jun/2010

Pasture productivity can drop due to soil compaction caused by animal trampling. Physical and mechanical alterations are therefore extremely important indicators for pasture management. The objective of this research was to: draw and evaluate the Mohr failure line of a Red Yellow Latossol under different pasture cycles and natural forest; calculate apparent cohesion; observe possible physical alterations in this soil; and propose a correction factor for stocking rates based on shear strength properties. This study was conducted between March/2006 and […]

Relationship between the soil water content and root penetration resistance of a dystrocohesive yellow argissol

Dreid de Cerqueira Silveira, José Fernandes de Melo Filho, José Augusto Amorim Silva do Sacramento, Edvana Cássia Pinto Silveira

01/Jun/2010

Soil resistance to root penetration is the main parameter to express the soil compaction degree and the facilities that it offers to root penetration. The purpose of this study was to characterize the ratio of the soil water content and root penetration resistance of a DystrocohesiveYellow Argissol in the Recôncavo Baiano (Bahia, Brazil). The study was carried out in a commercial citrus orchard with ‘Pera’ sweet orange (Citrus sinensis Osb.) grafted on ‘Rangpur’ lime (Citrus limonia Osbeck) with a green […]

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