Compressibility of Oxisol aggregates under no-till in response to soil water potential
01/Dec/2009
The system of no-till sowing stands out as being a technology that suits the objectives of more rational use of the soil and greater protection against the erosion. However, through till, any of it, occurs modifications of the soil’s structure. This current work aims to study the influence of the energy state of the water and of the organic matter on the mechanism of compaction of Red Oxisol under no-till management system. Humid and non-deformed sample were collected in horizon […]
Utilization of Boron (10B) derived from fertilizer by sugar cane
01/Dec/2009
The response to B in agricultural systems of sugar cane is still an unexplored issue; B application has however recently been widely publicized and used with a certain degree of frequency. The use of 10B-labeled fertilizers may further contribute to clarify this practice. With the objective of evaluating sugar cane use of B (10B) derived from fertilizer (boric acid), an experiment was conducted under field conditions in the 2005/2006 growing season. The experiment consisted of the installation of microplots (2 […]
Peat bogs of the Serra do Espinhaço Meridional – Minas Gerais, Brazil. I – characterization and classification
01/Oct/2009
Peat bogs are a special environment for studies related with the dynamics of organic matter, landscape evolution and climatic changes and with local, regional and global cycles of atmospheric pollution. Peat bogs contribute to the global C sequestration, act as water reservoirs and are the habitat of an endemic biodiversity. The Serra do Espinhaço Meridional (Minas Gerais State, Brazil) – SdEM – a terrestrial biosphere reservation area, contains a considerably large area with different types of peat bogs, which were […]
Occurrence of plant growth-promoting traits in clover-nodulating rhizobia strains isolated from different soils in Rio Grande do Sul state()
01/Oct/2009
In the last decades, the use of plant growth-promoting rhizobacteria has become an alternative to improve crop production. Rhizobium leguminosarum biovar trifolii is one of the most promising rhizobacteria and is even used with non-legume plants. This study investigated in vitro the occurrence of plant growth-promoting characteristics in several indigenous R. leguminosarum biovar trifolii isolated from soils in the State of Rio Grande do Sul, Brazil. Isolates were obtained at 11 locations and evaluated for indoleacetic acid and siderophore production […]
Environmental and agricultural benefits of a management system designed for sandy loam soils of the humid tropics
01/Oct/2009
A sustainable management of soils with low natural fertility on family farms in the humid tropics is a great challenge and overcoming it would be an enormous benefit for the environment and the farmers. The objective of this study was to assess the environmental and agronomic benefits of alley cropping, based on the evaluation of C sequestration, soil quality indicators, and corn yields. Combinations of four legumes were used in alley cropping systems in the following treatments: Clitoria fairchildiana + […]
Spatial variability of soil chemical properties after coffee tree removal
01/Oct/2009
Assessing the spatial variability of soil chemical properties has become an important aspect of soil management strategies with a view to higher crop yields with minimal environmental degradation. This study was carried out at the Centro Experimental of the Instituto Agronomico, in Campinas, São Paulo, Brazil. The aim was to characterize the spatial variability of chemical properties of a Rhodic Hapludox on a recently bulldozer-cleaned area after over 30 years of coffee cultivation. Soil samples were collected in a 20 […]
Topossequence of soils on the trindade island in the brazilian south atlantic
01/Oct/2009
The Brazilian Oceanic islands are unique environments which have received increasing attention from the scientific community due to their environmental importance. This study aimed to provide a first characterization of soils of the Trindade Island, considering mainly the chemical and physical properties in the different geoenvironments. Another objective was to contribute to a deeper undestanding of the pedogeomorphological relationships, allowing a preliminary identification of soils along a typical toposequence. A total of 10 soil profiles representing all geoenvironments were sampled. […]
Microbial alterations of the soil influenced by induced compaction
01/Oct/2009
Compaction is one of the most destructive factors of soil quality, however the effects on the microbial community and enzyme activity have not been investigated in detail so far. The objective of this study was to evaluate the effects of soil compaction caused by the traffic of agricultural machines on the soil microbial community and its enzyme activity. Six compaction levels were induced by tractors with different weights driving over a Eutrustox soil and the final density was measured. Soil […]
Water, soil, organic matter, and nutrient losses by rainfall erosion from an area of native pasture cropped with corn, influenced by tillage methods and fertilization types
01/Oct/2009
Despite the available knowledge on erosion of cultivated lands, there are situations of soil use and management that need more detailed studies. Based on that, this research work was accomplished with the objective of evaluating soil erosion by rainfall from an area of native pasture cropped with corn (Zea mays L.), under reduced-tillage and no-tillage, and mineral (chemical fertilizer containing N and P) and organic (poultry litter) fertilization. The study was developed in the field, at the Agriculture Experimental Station […]
Evolution of the landscape in the region of quadrilátero ferrífero (Minas Gerais, Brazil) based on the measurement of erosion rates (10be) and pedogenesis
01/Oct/2009
A geomorphological overview of the Quadrilátero Ferrífero reveals a conspicuous region where roots of metassedimentary Proterozoic strucutures, displaying young relief features, are in evidence over a sea of hills from the Archean basement. This paper deals with the landscape evolution in the “Quadrilátero Ferrífero” region, based on the integrated analysis of quantitative data of the erosion rates (10 Be) and of the soil types developed from the main rocks of the region. The 10Be concentration extracted from quartz of veins, […]
