Chemical composition of soil solution in different soil pore classes
01/Oct/2009
The chemistry of the soil solution can be regarded as an indicator of the presence of nutrients or contaminants in the soil. To evaluate the variation of this chemical composition in the soil pores, a sequential system of extraction of the soil solution from the different soil pore classes was used. Soil columns were constructed and filled with air-dried fine soil of a Dystrophic Ultisol, and irrigated with: distilled water (T1), treated wastewater (T2) and treated wastewater + 1.2 g […]
Nickel incorporation in Fe(II, III) hydroxysulfate Green Rust: effect on crystal lattice spacing and oxidation products
01/Oct/2009
Ni(II)-Fe(II)-Fe(III) layered double hydroxides (LDH) or Ni-containing sulfate green rust (GR2) samples were prepared from Ni(II), Fe(II) and Fe(III) sulfate salts and analyzed with X ray diffraction. Nickel is readily incorporated in the GR2 structure and forms a solid solution between GR2 and a Ni(II)-Fe(III) LDH. There is a correlation between the unit cell a-value and the fraction of Ni(II) incorporated into the Ni(II)-GR2 structure. Since there is strong evidence that the divalent/trivalent cation ratio in GR2 is fixed at […]
Soil carbon stocks under pasture in costal tableland areas in southern Bahia State, Brazil
01/Oct/2009
The replacement of forest environments by pastures leads to fundamental alterations in soil carbon stocks and consequently in the global cycle of this element. This study was conducted in the municipality of Itabela, Bahia, and the objective was to evaluate carbon stocks in soils of a natural forest in comparison to degraded and productive pastures with different usage periods. For this purpose, remnants of the Atlantic Forest, productive pastures after different periods of use (2, 9 and 18 years) and […]
Pedomorphogeological relations in the chapadas elevadas of the Distrito Federal, Brazil
01/Oct/2009
Detailed studies of pedologic characterization, as well as of relationships between pedology, geology and geomorphology are important for the comprehension of the soil distribution in a landscape. The objective of this study was to evaluate the pedomorphogeological relationships in the Chapadas Elevadas of the Distrito Federal, by the chemical, physical, mineralogical and geochemical characterization of the soils found in this landscape compartment. Two representative top-sequences of the pedologic distribution were selected in this geomorphologic unit, whose soils were formed from […]
Transport of boron in soil and its uptake by eucalypt
01/Oct/2009
The mechanism and magnitude of B transport to plant roots depend on both water and B soil contents. The contribution of mass flow and diffusion to the B transport in soil to eucalypt roots was evaluated in response to the water potential and B rates. Two water potentials (-10 and -40 kPa) and six B levels (0; 0.5; 1; 2; 3 and 5 mg dm-3 of B) were evaluated. The plants were grown in 2.5 dm3 plastic pots with soil, […]
Phosphorus and root distribution and corn growth as related to long-term tillage systems and fertilizer placement()
01/Oct/2009
Soil and fertilizer management during cultivation can affect crop productivity and profitability. Long-term experiments are therefore necessary to determine the dynamics of nutrient and root distribution as related to soil profile, as well as the effects on nutrient uptake and crop growth. An 18-year experiment was conducted at the Federal University of Rio Grande do Sul State (UFRGS), in Eldorado do Sul, Brazil, on Rhodic Paleudult soil. Black oat and vetch were planted in the winter and corn in the […]
Alterations in some properties of a degraded oxisol by sewage sludge and organic residue application
01/Oct/2009
The recovery of intensively impacted areas, as originated by the construction of a hydroelectric power plant, is a slow process and usually requires the addition of organic residues as source of organic matter and nutrients to improve the soil properties. The objective of this study was to verify the effects of the addition of sewage sludge and organic residues (wood shavings and sugar cane filter cake) on the growth of two Cerrado tree species, used in the recovery of the […]
Least limiting water range and porosity of cultivated soils in an environmental protection area in the south of Minas Gerais
01/Oct/2009
Restrictive physical conditions for an adequate plant development reduce the productive capacity of soils and environmental sustainability. An important parameter to express these restrictions is the least limiting water range (LLWR), which is used in combination with soil physical properties that influence plant development. To evaluate the LLWR and porosity of soils under coffee and pasture in the Capituvas River microbasin, a representative area of the Coqueiral Resereve was chosen. Undisturbed samples of a typical Dystrophic Red Latosol (LVd- Oxisol), […]
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 […]
