Response of sugar cane to application of slag as a corrective agent for acidity in soil
01/Mar/2001
High acidity predominates in southeastern and midwestern Brazilian soils, where the largest area of sugar cane plantations is concentrated. Large amounts of slag, a steel-industry residue containing nutrients such as calcium and magnesium and acting as acidity corrective agents, are also present in the region. This study aimed to evaluate different base saturation levels using slag as a soil corrective agent. This material was compared to calcitic limestone to analyze acidity neutralization and certain chemical soil properties, as well as […]
Soils as indicators of the relationships between continental and marine sediments on the coastal plain: Rio Guaratuba (SP)
01/Mar/2001
Two toposequences on the coastal plain of Rio Guaratuba (SP) were studied to define the pedological and deposition/storage evolution by means of macromorphological soil analysis. The first sequence shows the change of a Podzol into organic soil on marine sandy sediments, whereas the second one shows the relationship of a Gley Soil on continental sediments with a Podzol soil on marine sediments. Marine sedimentation was found to form sandbanks with internal depression zones, which allowed the development of a Podzol […]
Effect of sewage sludge and municipal waste compost on the soil hydraulic conductivity of a saturated and unsaturated Yellow Latosol
01/Mar/2001
This paper presents data of an experiment carried out in a Yellow Latosol amended with sewage sludge and municipal waste compost where sugar-cane was grown for two years. The experiment design was a random block with 9 treatments and 4 replications. The treatments were: tr1 – mineral fertilization + CaCO3; tr2, tr3; tr4 and tr5 – levels of sewage sludge (respectively, 0; 33; 66 and 99 Mg ha-1, in the first year, and 0; 37; 74 and 112 Mg ha-1, in the second year, in […]
Effects of native semiarid vegetation deforestation on soil and water losses of a haplargids in Sumé, Paraíba, Brazil
01/Mar/2001
The effects of native semiarid vegetation deforestation on soil and water losses caused by erosive rainfall in Haplargid were studied. The data covering the period of 1983-1990 were obtained from the Experimental Station of Sumé (Paraíba, from Brazil) of the Universidade Federal da Paraíba (UFPB). The treatments consisted of two deforested runoff plots, two runoff plots with native semiarid vegetation, two deforested watersheds and two watersheds with native semiarid vegetation. The deforested runoff plots, had soil losses of 61.7 and […]
The effect of winter plant cover and organic and, or, mineral fertilization on the bean/maize crop rotation
01/Dec/2000
This study was carried out to assess the influence of winter plant cover on the grain yield in the bean/maize crop rotation in a Structured Terra Roxa soil in the state of Santa Catarina. The plant cover consisted of an association of black oats (Avena stirgosa Schreb) with pasture turnip (Raphanus sativus L.) and organic fertilization with poultry manure and mineral fertilization. The soil cover influenced the grain yield in the bean plant, but not the maize. This may have […]
Intercropped black oat and common vetch as soil cover and their effect on corn
01/Dec/2000
With the increase of corn cultivation under the no-tillage system, various cover crop species have been evaluated to obtain a soil cover that benefits corn under succession and no-tillage. The objective of this work was to evaluate the effect of three sowing densities of black oat (Avena strigosa Scheig) and common vetch (Vicia sativa) in associated crops and as isolated crops and three levels of nitrogen fertilization (N), applied on corn (0, 60 and 160 kg ha-1 of N). Dry […]
Leaching of inorganic ions in soils continuously amended with biosolids
01/Dec/2000
The leaching of nitrates and the metals K, Ca, Mg, Cd, Cu, Cr, Ni, Pb and Zn were evaluated in an experiment using biosolids amended soils. The experiment was arranged in a completely randomized block design with four treatments: Typic Hapludox with and without biosolids (LA and LA + sludge) and Rhodic Hapludox with and without biosolids (LV and LV + sludge) and four replications. Biosolids were applied to soils every two months in an average rate corresponding to 78 […]
Changes in acid soil properties by superficial and incorporated liming on natural pasture
01/Dec/2000
Superficial liming is an alternative way to correct soil acidity in no till system. The objective of this study was to evaluate the effects of superficial and incorporated liming on native pasture. The experiment was carried out at the experimental field of the Soil Science Department, at the Universidade Federal de Santa Maria (Brazil), on a Plinthaquult medium texture and with high potential acidity under native pasture. Lime rates of 0.0, 2.0, 8.5 and 17.0 Mg ha-1 were used. On […]
Fractal nature of humic acids
01/Dec/2000
Among the tools used to describe the ramified structure or the rugged and distorted surface of humic acids (HA), fractal geometry seems to be one of the most adequate to explain the conformation of humic particles (molecular aggregates). From the experimental point of view, fractal dimension (D) of natural systems may be measured through the transmitted light, not scattered or absorved (turbidimetry’τ’). The presence of fractals indicates that the system may be decomposed in parts, each part being a copy […]
Nitrogen in soil and soil organic matter fractions affected by different corn production systems
01/Dec/2000
A long-term field trial was carried-out in Jaboticabal (SP) to estimate the effect of production systems on soil nitrogen and soil organic matter fractions. The treatments tested were corn in conventional sowing in summer and no tillage in winter (C-Mi-P), maize in direct sowing in summer and no tillage in winter (D-Mi-P), maize in direct sowing in summer, Mucuna aterrina as green manure in winter (D-Mi-Mu), maize in direct sowing in summer, Cajanus cajan as green manure in winter (D-Mi-Gu), […]