Estimation of soil moisture in the root-zone from remote sensing data
01/Jun/2013
Field-based soil moisture measurements are cumbersome. Thus, remote sensing techniques are needed because allows field and landscape-scale mapping of soil moisture depth-averaged through the root zone of existing vegetation. The objective of the study was to evaluate the accuracy of an empirical relationship to calculate soil moisture from remote sensing data of irrigated soils of the Apodi Plateau, in the Brazilian semiarid region. The empirical relationship had previously been tested for irrigated soils in Mexico, Egypt, and Pakistan, with promising […]
Changes in soil properties of a forest management area on the Araripe Plateau
01/Jun/2013
The Araripe Plateau in the tropic semi-arid region is characterized by great environmental diversity. The Araripe National Forest and several forest management units (FMU) are located in this area with mostly red-yellow Oxisols. The goal of this study was to identify a basic indicator that could represent a set of physical, chemical and biological properties of soils of the Plateau. Multivariate analysis was used to indicate changes in soil properties of a FMU. Soil samples were analyzed in triplicate (0-20 […]
Forms and accumulation of copper and zinc in a sandy typic hapludalf soil after long-term application of pig slurry and deep litter
01/Jun/2013
Successive applications of pig slurry and pig deep litter may lead to an accumulation of copper (Cu) and zinc (Zn) fractions in the soil profile. The objective of this study was to evaluate the Cu and Zn forms and accumulation in a Sandy Typic Hapludalf soil after long-term application of pig slurry and deep litter. In March 2010, eight years after initiating an experiment in Braço do Norte, Santa Catarina (SC), Brazil, on a Sandy Typic Hapludalf soil, soil samples […]
Nitrogen mineralization in latosols fertilized with organic residues
01/Jun/2013
The N mineralization rate varies from one organic residue to another, and depends on the chemical composition of a residue and its interaction with the soil. This study assessed the dynamics of N mineralization of organic residues incubated in Oxisols. The experiment was carried out from July 2007 to April 2008. Samples of manures, sludges, composts, peat, and substrate were incubated in washed sand, in a Red Yellow Latosol (RYL), and in a Red Latosol (RL), with 240 and 670 […]
Application of nitrogen mineralization method with leaching to soil amended with sewage sludge and organic compost
01/Jun/2013
The determination of the nitrogen (N) mineralization rate in waste-treated soils is important to calculate the residue rates to be applied, supplying plants with mineral N to at the appropriate time, without leaching losses. Most studies on residue-treated soils use the technique without leaching of mineral forms and the volumetric determination method. The repeatability of the test is however poor and the sensitivity of the determination method low, especially in soils amended with sewage sludge and organic compost. In this […]
Monitoring the soil redox potential and its interactions with associated variables in the Northern Pantanal
01/Jun/2013
The analysis of redox potential and other associated soil variables may be useful for understanding the dynamics of hydromorphic soils throughout the water cycle of the Pantanal. This study investigated the redox potential and soil variables (CO2, O2, temperature, moisture and matric potential) by continuous and uninterrupted monitoring. Measurements were made at 10 and 30 cm depth in a Haplic alitic gleisolic Planossol soil with Cerrado sensu stricto vegetation, in the municipality of Barão do Melgaço in the northeastern Pantanal. […]
Effects of nickel and nitrogen soil fertilization on lettuce growth and urease activity
01/Jun/2013
Nickel is a micronutrient involved in nitrogen metabolism and a constituent of the urease molecule. Plant growth and urease activity were evaluated in lettuce (Lactuca sativa L.) grown in soil-filled pots in a 2 x 8 factorial design with two nitrogen (N) sources and eight Ni rates, with five replications. Nitrogen was applied at 200 mg dm-3 (half the dose incorporated into the soil at seedling transplanting and half top-dressed later) using the sources NH4NO3 (AN) and CO(NH2)2 (Ur). The […]
Soil and phytosociological characterization of an area with predominance of arnica (Lychnophora pohlii sch. bip.)
01/Jun/2013
Lychnophora pohlii Sch. Bip. (Asteraceae), known as “Arnica mineira”, is widely used in folk medicine and very abundant in the altitude vegetation of rocky grassland. The aim of this work was to study the density of this species and its relationship with soil parameters in rocky grassland in Diamantina, in the Upper Jequitinhonha region, Minas Gerais. Ten contiguous 20 x 50 m plots were marked (total sampled area 10,000 m2) on the campus Juscelino Kubitschek of the Federal University of […]
Phosphorus extracted by ion exchange resins and mehlich-1 from oxisols (latosols) treated with different phosphorus rates and sources for varied soil-source contact periods
01/Jun/2013
Despite the large number of studies addressing the quantification of phosphorus (P) availability by different extraction methods, many questions remain unanswered. The aim of this paper was to compare the effectiveness of the extractors Mehlich-1, Anionic Resin (AR) and Mixed Resin (MR), to determine the availability of P under different experimental conditions. The laboratory study was arranged in randomized blocks in a [(3 x 3 x 2) + 3] x 4 factorial design, with four replications, testing the response of […]
Relationships between microbial activity and soil physical and chemical properties in native and reforested Araucaria angustifolia forests in the state of São Paulo, Brazil
01/Jun/2013
Araucaria angustifolia (Bert.) O. Kuntze is the main component of the Mixed Ombrophilous forest and, in the State of São Paulo, it is associated with a high diversity of soil organisms, essential for the maintenance of soil quality, making the conservation of this ecosystem a major and pressing challenge. The objective of this study was to identify the physical and chemical properties that are most closely correlated with dehydrogenase enzyme activity, basal respiration and microbial biomass under native (NF) and […]
