Volume 39, Number 6, 2015
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 […]
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 […]
Soil Vis-NIR Spectra and Fuzzy K-means on Definition of Soil Mapping Units in Topossequences
01/Dec/2015
ABSTRACT Knowledge of soils is increasingly important for their correct use in agriculture, in urban growth, and in conservation of natural resources, among other purposes. However, there is a lack of qualified professionals for pedological characterization and mapping, particularly at scales of greater detail. Due to this shortage and due to advances in computational tools and remote sensing, Digital Soil Mapping (DSM) arose in order to assist and expedite pedological survey activities. Thus, the aim of this study was to […]
Soil Macrofauna and Physical and Chemical Properties under Soil Management Systems in the Santa Catarina Highlands, Brazil
01/Dec/2015
ABSTRACT Soil use can change processes such as soil organic matter decomposition, nutrient cycling, and particle aggregation, which, in turn, influence the occurrence of macrofauna. The objective of this study was to relate land use systems to their effects on the distribution of soil macrofauna groups, as well as their relation to soil physical and chemical properties. The land use systems evaluated were native forest, an Eucalyptus plantation, pasture, a crop-livestock integration area, and a no-tillage crop area. Samples were […]
Growth and Nutrition of Eucalypt Rooted Cuttings Promoted by Ectomycorrhizal Fungi in Commercial Nurseries
01/Dec/2015
ABSTRACT Ectomycorrhizal fungi (EMF) may improve the adaptation of eucalypts saplings to field conditions and allow more efficient fertilizer use. The effectiveness of EMF inoculum application in promoting fungal colonization, plant growth, nutrient uptake, and the quality of rooted cuttings was evaluated for Eucalyptus urophylla under commercial nursery conditions. For inoculated treatments, fertilization of the sapling substrate was reduced by 50 %. The experiment was carried out in a completely randomized design in a 4 × 4 factorial arrangement, wherein […]
Characterization of Exopolysaccharides Produced by Rhizobia Species
01/Dec/2015
ABSTRACT Increasing attention has been given, over the past decades, to the production of exopolysaccharides (EPS) from rhizobia, due to their various biotechnological applications. Overall characterization of biopolymers involves evaluation of their chemical, physical, and biological properties; this evaluation is a key factor in understanding their behavior in different environments, which enables researchers to foresee their potential applications. Our focus was to study the EPS produced by Mesorhizobium huakuii LMG14107, M. loti LMG6125, M. plurifarium LMG11892, Rhizobium giardini bv. giardini […]
Herbicide use in Degraded Forest Areas in Restoration: Effects on Soil Invertebrate Biota
01/Dec/2015
ABSTRACT Chemical control of weeds is an effective method used in planted forests and in forest restoration, which plays an important role in development of forest seedlings and reduces costs of intervention. However, when this strategy is not properly applied, it may have negative impacts on soil organisms and on the ecological processes in which they take part. The goal of this study was to evaluate the effects of herbicide use on soil biota through sampling of the soil fauna […]
Microbiological Indicators of Pasture Soil with Successive Applications of Pig Slurry
01/Dec/2015
ABSTRACT Pig slurry use as soil fertilizer is a common practice in southern Brazil. In spite of the benefits of reusing waste, this practice poses serious environmental risks. Microbiological indicators of soil quality are very sensitive and allow soil environment conditions to be monitored. The aim of this study was to evaluate the microbiological quality of pasture soils with different histories of successive use of pig slurry. Determinations were made of C content in the microbial biomass, soil microbial respiration, […]
Initial Development of Two Sugarcane Varieties Inoculated with Diazotrophic Bacteria
01/Dec/2015
ABSTRACT Sugarcane is one of the most important crops in the economy due to production of sugar, ethanol, and energy. Technologies are necessary to improve its yield and quality with minimum damage to the environment. We evaluated the indole acetic acid production and germination in the sugarcane varieties RB867515 and IACSP95-5000 after inoculation with five strains of diazotrophic bacteria. The production of indole acetic acid was assayed through the colorimetric method using the Salkowski reagent. To evaluate germination, an experiment […]
Least Limiting Water Range and Load Bearing Capacity of Soil under Types of Tractor-Trailers for Mechanical Harvesting of Green Sugarcane
01/Dec/2015
ABSTRACT The expansion of the sugarcane industry in Brazil has intensified the mechanization of agriculture and caused effects on the soil physical quality. The purpose of this study was to evaluate the limiting water range and soil bearing capacity of a Latossolo Vermelho distroférrico típico (Rhodic Hapludox) under the influence of different tractor-trailers used in mechanical sugarcane harvesting. The experiment was arranged in a randomized block design with five replications. The treatments consisted of green sugarcane harvesting with: harvester without […]