Volume 39, Number 5, 2015
Leather Industry Waste as a Nitrogen Source for Wheat and Rice in Succession
01/Sep/2015
ABSTRACT The stabilization process necessary for leather tanning, in the leather industry, generates a great deal of collagenic solid waste, which is a likely pollutant. This solid waste has high nitrogen content, which suggests potential for agricultural use. To evaluate the feasibility of application of industrial leather waste as an N source for wheat and rice crops, a greenhouse experiment was conducted with five application rates of N from collagen (0, 225, 450, 675, and 900 mg kg-1) and three […]
Micronutrient Accumulation in Conilon Coffee Berries with Different Maturation Cycles
01/Sep/2015
ABSTRACT The number of days between anthesis and maturation of conilon coffee berries varies according to the genotype. Thus, it is believed that periods of greater nutrient demand for fruit formation also vary according to the genotype, directly influencing fertilizer management. The goal of this study was to establish accumulation curves for the micronutrients boron, copper, iron, manganese, and zinc in conilon coffee trees with different maturation cycles. The experiment was conducted in Nova Venécia, State of Espírito Santo, Brazil, […]
Liming in Agricultural Production Models with and Without the Adoption of Crop-Livestock Integration
01/Sep/2015
ABSTRACT Perennial forage crops used in crop-livestock integration (CLI) are able to accumulate large amounts of straw on the soil surface in no-tillage system (NTS). In addition, they can potentially produce large amounts of soluble organic compounds that help improving the efficiency of liming in the subsurface, which favors root growth, thus reducing the risks of loss in yield during dry spells and the harmful effects of “overliming”. The aim of this study was to test the effects of liming […]
Physical Quality of Soils in Agricultural Use in the Semiarid Region of the State of Bahia
01/Sep/2015
ABSTRACT Conversion of a natural condition to agricultural use can impose changes in soil properties and processes and bring environmental consequences to the region this agricultural use encompasses. The aim of this study was to evaluate the physical quality of the soil in agricultural areas of municipalities around Sobradinho Lake, a semiarid region in the State of Bahia, using multivariate analysis statistical techniques as a tool. Initially, descriptive statistical analysis and correlation analysis techniques and the normality test were applied, […]
Occasional Soil Turnover and Liming in a Clayey Oxisol Under a Consolidated No-tillage System
01/Sep/2015
ABSTRACT Accumulation of nutrients and surface compaction have been reported after a long time under a no-tillage system. The aim of this study was to evaluate soil chemical properties, bulk density, and crop yield following a single mechanical intervention associated with liming in a clayey Oxisol under a NT system for 17 consecutive years in Pato Branco, southwestern Paraná, Brazil. A randomized block experimental design was used in a split-plot arrangement, with plowing and harrowing of the soil in the […]
Soil Compaction Curve of an Oxisol Under Sugarcane Planted After In-row Deep Tillage
01/Sep/2015
ABSTRACT Soil tillage that maintains the productivity of sugarcane plantations, providing an area for the root development and without traffic on crop rows, has given rise to new technologies in rural areas. The purpose of this study was to evaluate the soil physical properties in two sugarcane plantations, one of which was prepared with deep tilling and the other with conventional tillage. The experiment was conducted in Lençóis Paulista, São Paulo State. Soil penetration resistance and relative density were analyzed. […]
Sheep Excreta as Source of Nitrous Oxide in Ryegrass Pasture in Southern Brazil
01/Sep/2015
ABSTRACT Livestock urine and dung are important components of the N cycle in pastures, but little information on its effect on soil nitrous oxide (N2O) emissions is available. We conducted a short-term (39-day) trial to quantify the direct N2O-N emissions from sheep excreta on an experimental area of ryegrass pasture growing on a Typic Paleudult in southern Brazil. Four rates of urine-N (161, 242, 323, and 403 kg ha-1 N) and one of dung-N (13 kg ha-1 N) were applied, […]
Experimental Method to Determine Some Physical Properties in Physics Classes
01/Sep/2015
ABSTRACT Particle density, gravimetric and volumetric water contents and porosity are important basic concepts to characterize porous systems such as soils. This paper presents a proposal of an experimental method to measure these physical properties, applicable in experimental physics classes, in porous media samples consisting of spheres with the same diameter (monodisperse medium) and with different diameters (polydisperse medium). Soil samples are not used given the difficulty of working with this porous medium in laboratories dedicated to teaching basic experimental […]
