Volume 36, Number 1, 2012

There is lack of research on Argissolos (Ultisols and Alfisols) in relation to theunderstanding of the pedologic variations. Variations can be analyzed by multivariate statisticsand the data numerically classified. The comparison between the numeric classification andthe hierarchical classification can contribute to the evolution of the Brazilian Soil ClassificationSystem (SiBCS). The aims of this research were to analyze the pedologic variation of Argissolosderived from sedimentary materials in the central region of Rio Grande do Sul and to validatethe organization of the […]

One of the factors affecting the distribution of native vegetation is soil formation. Therefore, soils under native vegetation can be highly informative with regard to a region and the original soil fertility, as records of conditions found before agricultural reclamation (agrosilvopasture). The purpose of this study was to assess soil fertility and texture under native vegetation fragments sampled during the Forest Survey of the State of Minas Gerais, Brazil. In general, the variability in all soil properties was high, except […]

In recent years, physic nut (Jatropha curcas L.) has attracted attention because of its potential for biofuel production. Although it is adapted to low-fertility soils, physic nut requires soil acidity corrections and addition of a considerable amount of fertilizer for high productivity. The objective of this research was to evaluate the effectiveness of arbuscular mycorrhizal fungi (AMF) (control without AMF inoculation, Gigaspora margarita inoculation or Glomus clarum inoculation) on increasing growth and yield of physic nut seedlings under different rates […]

Agricultural activity, by the application of different soil management practices, can cause impacts on soil production capacity that need to be assessed. In this study, different microbiological parameters were evaluated, to assess the relation of soil quality with different tillage practices and crop systems, in comparison to a natural reference soil. The activities of β-glucosidase, urease, acid phosphatase and arylsulphatase were evaluated, as well as soil microbial respiratory activity and microbial biomass. Conventional tillage (CT) and no-tillage (NT) were evaluated […]

Because of the climate changes occurring across the planet, especially global warming, the different forms of agricultural soil use have attracted researchers´ attention. Changes in soil management may influence soil respiration and, consequently, C sequestration. The objectives of this study were to evaluate the long-term influence of liming on soil respiration and correlate it with soil chemical properties after two years of liming in a no-tillage system. A randomized complete block design was used with six replications. The experimental treatments […]

The alterations in the communities of arbuscular mycorrhizal fungi (AMF) induced by changes in land use and different agricultural uses are still insufficiently studied, particularly in the Cerrado biome. This study evaluated how human interference by management and land use change affect the AMF density and diversity in a Cerrado Oxisol. The study evaluated five areas: Riparian Forest (MC), Riparian Forest Edge (BM), Pasture (Past), no-till monoculture (PD) and Riparian Deforested Area (AD). In each area, 20 plots of 250 […]

Sugarcane, which involves the use of agricultural machinery in all crop stages, from soil preparation to harvest, is currently one of the most relevant crops for agribusiness in Brazil. The purpose of this study was to investigate soil physical properties and root growth in a eutroferric red Oxisol (Latossolo Vermelho eutroférrico) after different periods under sugarcane. The study was carried out in a cane plantation in Rolândia, Paraná State, where treatments consisted of a number of cuts (1, 3, 8, […]

Grass pastures, if well-established and managed, play an important environmental role as soil cover, for aggregate formation and stabilization and in the reduction of dense or compacted layers. The objectives of this study were to quantify the least limiting water range (LLWR) of a physically degraded Red-Yellow Latosol (Oxisol) on which bermudagrass (Cynodon spp., cultivar coastcross) was planted, and to use the LLWR as an indicator of changes in the soil structural quality. Undisturbed samples were collected in volumetric rings […]

Soil management strategies to improve and maintain soil physical quality (SPhQ) are essential for the sustainability of intensive agricultural systems. The least limiting water range (LLWR) is an indicator of SPhQ defined by the range of least restrictive soil water content to plants, i.e., a soil water content within the LLWR indicates an appropriate SPhQ for plants. In this context, soil mulching with crop residues can contribute to the SPhQ by increasing the frequency at which soil water availability is […]

Soil penetration resistance is an important property that affects root growth and elongation and water movement in the soil. Since no-till systems tend to increase organic matter in the soil, the purpose of this study was to evaluate the efficiency with which soil penetration resistance is estimated using a proposed model based on moisture content, density and organic matter content in an Oxisol containing 665, 221 and 114 g kg-1 of clay, silt and sand respectively under annual no-till cropping, […]