ECOTOXICOLOGICAL ASSESSMENT OF COAL MINING WASTE
01/Dec/2015
ABSTRACT The disposal of large amounts of coal mining waste chemically modifies the soil, and this may change the structure and activity of soil fauna. The objective of this investigation was to study the ecotoxicological effects of depositions of pyritic waste (coal plus pyrite) in two soils collected in Santa Catarina, Argissolo Vermelho-Amarelo (Ultisol) e Nitossolo Háplico (Hapludox), at the application rates of 0, 2.5, 5, 10, and 20 % of that residue. Survival and reproduction of Enchytraeus crypticus and […]
Carbon Stock and Natural Abundance of 13C as a Function of Conversion of Forest and Grassland Areas in Southern Brazil
01/Dec/2015
ABSTRACT Conversions of plant cover resulting from management practices may alter carbon storage and the natural abundance of 13C. The aim of this study was to evaluate C stocks and natural abundance of C (δ13C) in areas of forest (F) and pasture (P) sequences with different times of usage in an Atlantic Forest area, Santa Catarina, Brazil. Seven usage sequences of forest (F) and pasture (P) were defined through aerial photographs taken in 1957, 1978, and 2008; through interviews with […]
BRACHIARIA IN SELENIUM-CONTAMINATED SOIL UNDER SULPHUR SOURCE APPLICATIONS
01/Dec/2015
ABSTRACT High contents of plant-available selenium in the soil in the form of selenate, resulting from natural or anthropogenic action, jeopardizes agricultural areas and requires research for solutions to establish or re-establish agricultural or livestock operation, avoiding the risk of poisoning of plants, animals and humans. The purpose was to evaluate sulfur sources in the form of sulfate, e.g., ammonium sulfate, calcium sulfate, ferric sulfate, in the remediation of tropical soils anthropogenically contaminated with Se under the tropical forage grass […]
Nodulations and Grain Yields of Common Beans in Response to Nitrogen Fertilization or Seed Inoculation with Rhizobium Freirei
01/Dec/2015
ABSTRACT Knowledge of the responses of bean plants as a function of N fertilization or seed inoculation with rhizobia can direct crops to different market niches in different technological levels. The roots nodulation and the yield grains of 10 bean cultivars on nitrogen fertilization and seed inoculation with Rhizobium freirei were evaluated aiming to identify, in terms of grain yield, the more efficient and responsive to nitrogen fertilization, as well to symbiotic N fixation in relation to N fertilization. Two […]
PROCESS OF GENERATING ACID MINE DRAINAGE AND HEAVY METAL CONTAMINATION IN PROFILES OF REBUILT SOIL IN A COAL MINING AREA
01/Dec/2015
ABSTRACT Soils rebuilt after coal strip mining is composed of topsoil and, or, overburden, and their chemical properties differ from those of natural soils mainly due to the sulfurization process. The objective of this study was to evaluate the potential for acidification from sulfides and heavy metal contamination across profiles of soils rebuilt after coal mining, in areas of different ages, with and without concomitant environmental reclamation during mine operations. Mining areas of different ages were selected: areas I and […]
Effect of Nitrogen and Potassium Rates on Early Development of Macaw Palm
01/Dec/2015
ABSTRACT The economic exploitation of macaw palm [Acrocomia aculeate (Jacq.) Lodd. ex Mart.] is currently in transition, from extractivism to agricultural cultivation, thus requiring studies on the fertilization of the crop. This study evaluated the response of three genotypes of macaw palm to increasing rates of nitrogen and potassium, grown in the field until the 2nd year and to establish reference contents of mineral nutrients in the leaf. The experiment was a split-plot randomized block design with five main treatments […]
Intermittent Pond Areas in Coastal Tablelands of the Reconcavo Region of Bahia, Brazil: Genesis of Areas, Characterization, and Soil Classification
01/Dec/2015
ABSTRACT Coastal Tablelands are flattened areas cut by valleys, which have predominantly Argissolos Amarelos (Yellow Argisol) and Latossolos Amarelos (Yellow Latosol). In contrast to this landscape, there are depressed circular areas, known as ponds, that create new dynamics in soil formation, due to the intermittent presence of water throughout the year. The soils of these pond areas are little known, which leads to the possibility of inappropriate use and management. The objective of this study was to describe the soils […]
CROP RESIDUE DECOMPOSITION AND NUTRIENT MINERALIZATION IN SOIL WITH DIFFERENT TEXTURES
01/Dec/2015
ABSTRACT The sustainability of conservation farming systems is closely linked to return of nutrients to the soil through decomposition of crop residues. The aim of this study was to evaluate decomposition of crop residues and nutrient mineralization in soils with different textures over a 175-day incubation period. The experimental design consisted of a 6 × 4 × 5 factorial arrangement – six treatments, composed of four crop residues (corn, brachiaria, common bean, and Stylosanthes) and two controls, both without residues, […]
Relationship between Soil Properties and Vegetation in the Ecotone Region of the Middle São Francisco River Valley, Brazil
01/Dec/2015
ABSTRACT The Middle São Francisco River valley is a vast territorial area with marked seasonal change and diversity of lithology, landscapes, soil, and vegetation. However, the relationships between soil characteristics and plant communities are poorly known. In this study, we show the relationships between key soil properties that determine the establishment of savanna-steppe, wooded savanna-steppe, savanna, semideciduous forest, and deciduous forest in this region through analysis of 166 soil profiles. In general, savanna soils are much more leached, Al-saturated, and […]
NUTRIENT AVAILABILITY AND RECOVERY FROM CROP RESIDUES IN SOIL WITH DIFFERENT TEXTURES
01/Dec/2015
ABSTRACT Crop residues on the soil surface not only provide physical protection but may release significant amounts of nutrients to the soil through decomposition. However, the availability of these nutrients to plants has not been sufficiently studied. The aim of this study was to evaluate the total contents of organic C and N, pH, and the availability and recovery rate of P, K, Ca, Mg, and S from the biogeochemical cycling of different crop residues over time in built soils […]