Maize root growth is negatively affected by compacted layers in the surface (e.g. agricultural traffic) and subsoil layers (e.g. claypans). Both kinds of soil mechanical impedances often coexist in maize fields, but the combined effects on root growth have seldom been studied. Soil physical properties and maize root abundance were determined in three different soils of the Rolling Pampa of Argentina, in conventionally-tilled (CT) and zero-tilled (ZT) fields cultivated with maize. In the soil with a light Bt horizon (loamy […]

Chiseling is one of the mechanical practices that can be used in no-tillage (NT) soils in order to reduce soil bulk density, resistance to root penetration, and to increase water permeability. The effect of these changes on plant growth and consequently on grain yield depends on climatic conditions. In soils with ideal moisture conditions, the physical limitations tend to be less noticeable. This study aimed to analyze the changes in the physical and hydric properties of a chiseled Oxisol under […]

Preconsolidation pressure is currently used as a tool in the study of the soil compaction process. The purpose of this work was to determine the layout and number of samples required for the determination of the preconsolidation pressure (sp) in a Red Latosol, as well as to characterize its variability and spatial distribution using classical statistics and geostatistics parameters. The study was carried out in an experimental farm area, in Lavras, Minas Gerais State, Brazil, conventionally tilled in the last […]

Soil compaction is one of the most important reasons for decrease in crop yield. The impact of animal trampling on integrated beef cattle raising-crop production systems were studied to evaluate the changes in soil physical properties (bulk density, porosity, soil resistance to penetration and soil water infiltration). The field experiment was carried out in Jari, in the mid- plateau region of Rio Grande do Sul State, Brazil. Three management systems of winter pastures (black oat; Avena strigosa Schreber + ryegrass; […]

The intensive traffic of agricultural machines on soils used for hay production can result in soil quality degradation. The hypothesis evaluated was that systems of intensive hay production cause soil physical degradation. The objective of this study was to quantify the soil physical properties and morphological attributes to recognize and identify the soil physical degradation of a Red Latosol (Typic Haplorthox) cropped with Tifton 85 forage (Cynodon spp) for hay production, in western Paraná state, southern Brazil. A native forest […]

The integration of farming and cattle production activities in no-tillage system areas with winter cover crops can be an income supplement for summer grain farmers. However, many of them are afraid of adopting this integration system, because of possible negative effects of animal treading on soil attributes, mainly of those related to soil compaction. This study was conducted: (1) to determine the alterations in the soil physical attributes promoted by animal treading; (2) to verify if the alterations in soil […]

The soil physical quality is fundamental for the sustainability of citrus production. The objective of this study was to evaluate the homogeneity of soil physical quality in-between the rows of an orange orchard with groundcover management systems. The study was performed in an experimental field with groundcover systems in-between the rows of ‘Pêra orange’ on ‘Rangpur’ lime rootstock on a Typic Paleudult, in 1993, in Alto Paraná, in the northwestern region of the state of Paraná, Brazil. An experimental design […]

The least limiting water range (LLWR) was used to determine several factors that influence plant growth. The LLWR is defined as the water content range in which aeration (AFP) and soil resistance to root penetration (RP) are not restrictive, within the field capacity (FC) and permanent wilting point (PWP). The aim of the present study was to determine the LLWR and soybean grain yield in an Oxisol under non-tillage (NT) and chiseled no-tillage (CNT) systems. The soil density, LLWR, soil […]

For aggregated soils the Mohr failure line can be separated into two straight lines, with different slopes and intercepts. In the range of low normal load, when the slope is very steep and the intercept is small, the failure line is defined by the friction and cohesion inter-aggregates, while for the higher load range the slope becomes smaller and intercept is larger, which defines the intra-aggregate friction and cohesion. Therefore, for aggregated soils the normal load range used in the […]

The objective of this report was to verify the form of vertical and horizontal spatialization of chemical, physical and water quality indicators of a Typic Haplortox cultivated with citrus. The ‘Valencia’ orange grove on ‘Rangpur’ lime was planted in 1995, in the county of Alto Paraná, northwestern Paraná, Brazil. In August 2002, undisturbed and disturbed samples were collected for chemical, physical and water analysis. Twenty-four transects were sampled perpendicular to the tree trunk, in two layers (0-0.20 and 0.20-0.40 m depth) […]