Soil penetration resistance (PR) is a measure of soil compaction closely related to soil structure and plant growth. However, the variability in PR hampers the statistical analyses. This study aimed to evaluate the variability of soil PR on the efficiency of parametric and nonparametric analyses in indentifying significant effects of soil compaction and to classify the coefficient of variation of PR into low, medium, high and very high. On six dates, the PR of a typical dystrophic Red Ultisol under […]

Agriculture and soil management in the Cerrado can cause soil compaction, resulting in decreased porosity and water and nutrient availability, with a negative impact on plant growth and development. The objective of this study was to evaluate the effect of soil density and phosphorus doses (P) on soybean and eucalyptus grown in two Cerrado oxisols with different texture: one (LV) with 610 g kg-1 clay and the other (LVA), with 190 g kg-1 clay. Three soil densities (0. 90, 1. 10 and 1. 30 Mg m-3) […]

Soil fertility can be evaluated by several methods, such as field or greenhouse tests with plants. In greenhouse studies with untilled soils the sampling of undisturbed soil cores is difficult. The aim of this study was to propose an equipment for undisturbed soil core sampling of untilled soils for greenhouse studies and test its efficiency. A sampler with a diameter of 200 mm and depth of 300 mm was developed. The soil penetration resistance and density of the soil and […]

Restrictive physical conditions for an adequate plant development reduce the productive capacity of soils and environmental sustainability. An important parameter to express these restrictions is the least limiting water range (LLWR), which is used in combination with soil physical properties that influence plant development. To evaluate the LLWR and porosity of soils under coffee and pasture in the Capituvas River microbasin, a representative area of the Coqueiral Resereve was chosen. Undisturbed samples of a typical Dystrophic Red Latosol (LVd- Oxisol), […]

The sustainability of irrigated rice (Oryza sativa L.) in lowland soils is based on the use of crop rotation and succession, which are essential for the control of red and black rice. The effects on the soil properties deserve studies, particularly on soil compaction. The objective of this study was to identify compacted layers in an Albaqualf under different cultivation and tillage systems, by evaluating the soil bulk density (Ds) with Gamma Ray Computed Tomography (TC). The analysis was carried […]

The soil quality of a crop-livestock system can change according to the pasture and soil management. This research was carried out in Otacilio Costa, Santa Catarina State, southern Brazil, on a Humic Cambisol previously used with native grass pasture for 9 years, desiccated in May 2003, for use with ryegrass (Lolium multiflorum) pasture in the winter and corn in the summer. A split plot design was used, consisting of pasture management systems and soil tillage systems prior to the summer […]

The estimate soil resistance to penetration curves (RPC) based on readily obtained variables such as water content, is a useful not only for the evaluation of soil compaction, but also to simplify the interpretation of soil resistance to penetration under different field conditions. The objective of this study was to estimate the RPC in soils of different textures and bulk densities based on data obtained with an impact penetrometer. The experiment was carried out at the Faculdade de Ciências Agrárias […]

Soil compaction is a serious problem for the soil quality and development of sustainable agriculture, because compaction affects the flow of soil water and air and reduces crop yields. One of the possibilities to tackle this problem is the use of plants with a deep and vigorous rooting system. The objective of this study was to evaluate the physical quality of a Typic Hapludalf, in a no-tillage system, after the use of cover crops, and to measure the critical limit […]

Soil resistance to root penetration is an important physical characteristic for defining soil management techniques. The purpose of this study was to estimate the mechanical soil penetration resistance of an Oxisol under perennial crop, at three gravimetrical moisture contents, based on bulk density, moisture, and soil clay and organic matter content. The soil penetration resistance was evaluated by an impact penetrometer and the impact data in dm-1 were converted into dynamic resistance (MPa). At the moment of the determination of […]

Soil resistance to penetration (PR) frequently reduces plant root growth. PR increases with soil bulk density (Bd) and decreases with soil moisture (θ), and the mathematical description of the relationships of PR with Bd and θ determines the soil penetration resistance curve (SRC). The objective of this study was to quantify the SRC of an Oxisol under different land use practices and to use it to describe soil physical degradation. Four areas were selected: (a) native forest; (b) pasture cultivated […]