The development of water erosion occurs in response to the way water moves through and over a given landscape. The digital elevation model (DEM) must therefore be as accurate as possible, since it is the basis for the analysis of a relief. The objectives of this study were to define a hydrologically consistent digital elevation model (HCDEM) and the most appropriate method to determine the flow direction of the drainage network in the sub-basin of the Terra Dura forest stand, […]

Cotton is responsive to boron fertilization, however, results on the mobility of this nutrient in the plant are few and controversial. This study had the objective of evaluating boron translocation and accumulation in cotton cultivars. Four cotton cultivars (FM 993, FM 910, FMT 701, and FMT 523) were grown for six weeks in 8 L pots with washed sand and nutrient solution at two boron concentrations (0 and 4.5 ∝mol L-1). After six weeks, plants were sampled for four more […]

Crop-livestock integration represents an interesting alternative of soil management, especially in regions where the maintenance of cover crops in no-tillage systems is difficult. The objective of this study was to evaluate soil physical and chemical properties, based on the hypothesis that a well-managed crop-livestock integration system improves the soil quality and stabilizes the system. The experiment was set up in a completely randomized design, with five replications. The treatments were arranged in a 6 x 4 factorial design, to assess […]

The dispersion of the samples in soil particle-size analysis is a fundamental step, which is commonly achieved with a combination of chemical agents and mechanical agitation. The purpose of this study was to evaluate the efficiency of a low-speed reciprocal shaker for the mechanical dispersion of soil samples of different textural classes. The particle size of 61 soil samples was analyzed in four replications, using the pipette method to determine the clay fraction and sieving to determine coarse, fine and […]

Urea is the most consumed nitrogen fertilizer in the world. However, its agronomic and economic efficiency is reduced by the volatilization of NH3, which can reach 78 % of the applied nitrogen. The coating of urea granules with acidic compounds obtained by charcoal oxidation has the potential to reduce the volatilization, due to the acidic character, the high buffering capacity and CEC. This work aimed to evaluate the effect of HNO3-oxidized carbon on the control of NH3 volatilization. These compounds […]

Soil moisture using the time domain reflectometry (TDR) has been evaluated using probes or waveguides (length > 0.10 m), with little information in the literature for lower lengths. The purpose of the study was to evaluate the estimation of soil moisture from the dielectric constant using TDR probes with different rod lengths. TDR waveguides were fabricated with different rod lengths (0.30, 0.15, 0.12, 0.10, 0.08, 0.06, and 0.04 m). In the laboratory, the soil was placed for drying in air, […]

In the determination of carbon contents in organic residues, analytical methods for soils are frequently employed without adequate calibration. Thus, methods capable to determine the levels of C and organic matter (OM) in organic residues must be tested and calibrated, using as a reference the dry combustion method. The objectives of this study were to evaluate methods for determining the levels of total carbon (TC), organic carbon (OC) and OM in organic residue samples; to determine mathematical equations for the […]

Araucaria angustifolia, commonly named Araucaria, is a Brazilian native species that is intensively exploited due to its timber quality. Therefore, Araucaria is on the list of species threatened by extinction. Despite the importance of soil for forest production, little is known about the soil properties of the highly fragmented Araucaria forests. This study was designed to investigate the use of chemical and biological properties as indicators of conservation and anthropogenic disturbance of Araucaria forests in different sampling periods. The research […]

Soil organic matter depletion caused by agricultural management systems have been identified as a critical problem in most tropical soils. The application of organic residues from agro-industrial activities can ameliorate this problem by increasing soil organic matter quality and quantity. Humic substances play an important role in soil conservation but the dynamics of their transformations is still poorly understood. This study evaluated the effect of compost application to two contrasting tropical soils (Inceptisol and Oxisol) for two years. Soil samples […]

The impact of pig slurry and poultry litter fertilization on soils depends on the conditions of use and the amounts applied. This study evaluated the effect of organic fertilizers after different application periods in different areas on the physical properties and organic carbon contents of a Rhodic Kandiudox, in Concordia, Santa Catarina, in Southern Brazil. The treatments consisted of different land uses and periods of pig and poultry litter fertilization: silage maize (M7 years), silage maize (M20 years), annual ryegrass […]