3290 results

Kinetics of lead release from soils in heavy metal mining and metallurgy area

Brenda Novaes Buschle, Jussara Kasuko Palmeiro, Youssef Bacila Sade, Vander de Freitas Melo, Maurício Gomes de Andrade, Araína Hulmann Batista

01/Dec/2010

Kinetics studies of heavy metal release are an important form of environmental diagnostics in contaminated areas, due to the possibility of determining, aside from the total release contents after increasing equilibrium times, the rate (velocity) of heavy metal to soil solution. The objective of this study was to determined Pb kinetics release from soils of the heavy metal mining and metallurgy area in Adrianópolis (PR), Brazil, in the Ribeira river valley. Eight soils were exposed to different contamination forms: (soils […]

Pedotransfer functions to estimate proctor test parameters under different tillage systems

Carina Rosa Álvarez, Federico Guillermo Micucci, Carolina Bustingorri, Miguel Angel Taboada

01/Dec/2010

The Proctor test is time-consuming and requires sampling of several kilograms of soil. Proctor test parameters were predicted in Mollisols, Entisols and Vertisols of the Pampean region of Argentina under different management systems. They were estimated from a minimum number of readily available soil properties (soil texture, total organic C) and management (training data set; n = 73). The results were used to generate a soil compaction susceptibility model, which was subsequently validated using a second group of independent data (test data […]

Microbiological and chemical soil properties in deserting areas in the semiarid region of Pernambuco State, Brazil

Carolina Malala Martins, Izabel Cristina de Luna Galindo, Edivan Rodrigues de Souza, Henrique Arruda Poroca

01/Dec/2010

To analyze the process of degradation caused by natural or anthropogenic influences tools are required, preferentially low-cost, to indicate the degradation stages aiming the selection of techniques to reclaim degraded areas. The purpose of this study was to analyze the variability of microbiological and chemical soil properties as indicators of desertification processes in areas with increasing levels of degradation in the semiarid region of the State of Pernambuco, Brazil. Three environments were sampled: conserved, moderately degraded and heavily degraded in […]

Chemistry and genesis of soils developed under restinga vegetation in São Paulo State, Brazil

Maurício Rizzato Coelho, Pablo Vidal-Torrado, Xosé Luiz Otero Pérez, Vanda Moreira Martins, Felipe Macías Vázquez

01/Dec/2010

Restinga is a term currently used for the vegetation on the poor and sandy soils of the coastal plains of Brazil. The soils of these environments have been poorly studied. The counties Cananéia, Ilha Comprida and Bertioga were selected for this research due to the representativeness of the environmental conditions of the state of São Paulo. In these environments 31 soil profiles were described and sampled, many of them in chronosequences. The samples were characterized chemically and analytical evidence converged […]

Urease activity as influenced by planting system and plant cover in soil under common bean

Anna Cristina Lanna, Pedro Marques da Silveira, Mozaniel Batista da Silva, Tatiana Maris Ferraresi, Huberto José Kliemann

01/Dec/2010

Urease is an enzyme that hydrolysis urea in carbon dioxide and ammonia. Urease distribution and influencing factors are highly relevant for the use of urea in agriculture. In this context, the purpose of this study was to verify the adequate time of soil sampling to measure urease activity, after N application to common bean as related to different soil tillage systems and cover plant species. The experiment was conducted on a dystrophic Dark Red Latosol where common bean cultivar Valente […]

Physical properties of a rhodic haplustox under two sugarcane harvesting systems

Walquíria Machado, Tiago Santos Telles, João Tavares Filho, Maria de Fátima Guimarães, Grace Bungenstab Alves, José Luiz Bernardo Borges

01/Dec/2010

This study had the purpose of evaluating the effects of two management types of sugarcane: harvesting of burnt cane (BCH) and mechanized harvesting of unburnt green cane (MCH), on some soil physical properties of a dystrophic Rhodic Haplustox. The data were then compared with results for the same soil type under native forest. A completely randomized design was used, with three treatments and 20 replications. The following characteristics were determined: organic matter, aggregate stability, soil bulk density, and porosity at […]

Aspects of common bean yield with a high technological management level as correlated with soil physical properties

Rafael Montanari, Morel de Passos e Carvalho, Marcelo Andreotti, Flávio Carlos Dalchiavon, Lenon Henrique Lovera, Max Alexandre de Oliveira Honorato

01/Dec/2010

Common bean yield was analyzed in relation to some physical properties of a dystroferric Red Latosol (Typic Acrustox), in the 2006/07 growing season, in Selviria, state of Mato Grosso do Sul, Brazil. The no-tillage crop under center-pivot irrigation was cultivated with a high technological management level. The objective of this work was to select the most representative soil properties to explain the variability in agricultural productivity. A geostatistical grid was installed for soil and plant sampling at 117 points, in […]

Portable penetrometer for agricultural soil: sensitivity test to identify critical compaction depth

João Carlos Medeiros, Getulio Coutinho Figueiredo, Álvaro Luiz Mafra

01/Dec/2010

To express the negative effects of soil compaction, some researchers use critical values for soil mechanical strength that severely impair plant growth. The aim of this study was to identify this critical compaction depth, to test the functionality of a new, portable penetrometer developed from a spring dynamometer, and compare it to an electronic penetrometer traditionally used in compaction studies of agricultural soils. Three soils with distinct texture were conventionally tilled using a disk plow, and cultivated with different plant […]

Land suitability evaluation as subsidy to the settlement of rural famylies, using geographic information system

Elisângela Benedet da Silva, Ruth Emília Nogueira, Antônio Ayrton Auzani Uberti

01/Dec/2010

Rural settlements in Brazil were created in order to confront pressures and are characterized by the lack of planning prior to the diagnosis and implementation of the natural resources related to land suitability evaluation, distribution of classes such as topography, rivers system, vegetation, and support mechanisms. The aim of this study was to evaluate the agricultural capacity of the lands which were allotted to the settlement of rural families by the National Institute of Colonization and Land Reform (INCRA), applying […]

Morphological and molecular characterization of Pisolithus in soil under eucalyptus plantations in Brazil

Maria Catarina Megumi Kasuya, Irene da Silva Coelho, Daniela Tiago da Silva Campos, Elza Fernandes de Araújo, Yutaka Tamai, Toshizumi Miyamoto

01/Dec/2010

Eighteen Pisolithus basidiomes were collected from Eucalyptus plantations in the state of Minas Gerais, Brazil. These basidiomes were characterized morphologically and molecularly. The basidiomes varied in shape, color and size. One of them was found underground, indicating a hypogeous fungus. The main morphological distinctive characteristic was spore ornamentation, which distinguished two groups. One group with short and erect spines was identified as Pisolithus microcarpus, and the other with long and curved spines as Pisolithus marmoratus, after analyzing the cladogram obtained […]

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