Volume 30, Number 4, 2006
Nitrogen application timing and soil inorganic nitrogen dynamics under no-till oat/maize sequential cropping
01/Aug/2006
The timing of N application to maize is a key factor to be considered in no-till oat/maize sequential cropping. This study aimed to evaluate the influence of pre-planting, planting and sidedress N application on oat residue decomposition, on soil N immobilisation and remineralisation and on N uptake by maize plants in no-till oat/maize sequential cropping. Undisturbed soil cores of 10 and 20 cm diameter were collected from the 0-15 cm layer of a no-till Red Latossol, when the oat cover crop was […]
Water-erosion related parameters under steady runoff-rate for different soil tillage methods
01/Aug/2006
Tillage influences both surface and subsurface soil physical conditions, and consequently the values of the factors related to the rainfall-water erosion process. A field experiment using simulated rainfall was conducted from October, 1999 to May, 2000, in the Planalto Sul Catarinense region, Lages, Santa Catarina State, Brazil, in order to evaluate some of the factors related to the rainfall-water erosion process under steady runoff-rate, with three different soil tillage methods. The soil used in the study was a clayey Typic […]
Absorption of soil native nitrogen by corn under no-tillage in succession to cover crops
01/Aug/2006
In untilled soils with green manure cultivation in during the dry season and the management of the nitrogen fertilization usually change the dynamics and the recovery of the nitrogen in the soil-plant system. The objective of this study was to evaluate the amount of native soil nitrogen absorbed by corn under no-tillage and submitted to different N rates in succession to sunnhemp (Crotalaria juncea), millet (Pennisetum americanum) and fallow in a Red Latosol in the Cerrado. The experiment was carried […]
Soil education: principles, theory and methods
01/Aug/2006
The importance of soils in the environment is frequently overlooked and undervalued. It is therefore necessary to develop “soil awareness”, within an educational process that is focused on a concept of sustainability in the man-nature relationship. There are many forms, moments and opportunities for environmental education based on a pedological approach. This ensemble of methods and topics represents Soil Education, an essential part of environmental education. Soil education aims to bring the significance of soils into the lives of people, […]
Use of biosolids for corn (Zea mays, L.) production in the Federal District
01/Aug/2006
The final disposal of sewage sludge is a growing concern worldwide as it has impacts on the water availability and quality for consumption, and economic activities. The Companhia de Saneamento Ambiental do Distrito Federal (CAESB) processes 400 t of biosolids a day that is rich in mineral nutrients and organic matter. Despite the lack of local agronomic criteria for use, biosolids has found a growing demand in grain, fruit crops, coffee and pastures cultivation. To evaluate the immediate (first year) […]
Potential acidity estimated by pH SMP method in soils of the Jequitinhonha Valley, Minas Gerais state, Brazil
01/Aug/2006
The potential acidity is important because it is used in the determination of base saturation and the estimation of lime requirement. The objective of this study was to establish a regression equation to estimate the potential acidity with the SMP-pH measured in water under agitation of the SMP equilibrium solution with soil samples from the Jequitinhonha Valley, Minas Gerais State, Brazil. The H + Al concentration measured by 0.5 mol L-1 calcium acetate pH 7.0 and SMP pH were determined in 50 soil samples at […]
