ABSTRACT Burning is a common practice in tropical areas and related changes in mineralogy might affect the chemical and physical behavior of soils. Maghemite is a common iron oxide in soils formed from basic rocks in tropical regions. This mineral and hematite are the main pigments in these soils and exhibit high magnetization stemming from the precursor magnetite formed during the weathering process of primary minerals. The objective of the present study was to analyze changes in color, magnetic suceptibility […]

ABSTRACT Decomposition of leaf litter from pioneer tree species and development of associated soil meso- and macrofauna are fundamental for rehabilitation processes in reclaimed coal mining areas. The aim of our study was to evaluate decomposition of Schinus terebinthifolius and Senna multijuga to answer three basic questions: (i) What type of leaf litter degrades faster in reclaimed coal mining areas? (ii) Is leaf decomposition correlated with the stage of regeneration and exposure time? and (iii) Does the type of leaf […]

ABSTRACT Despite limited geographic expression of Organosols in Brazil, their high carbon storage capacity and natural environmental vulnerability justifies further studies on C and N stocks in these soils and their relationship to the nature of organic matter. Evaluation of physical and chemical properties of organic soils and their ability to store C is important so as to develop sustainable management practices for their preservation. The objectives of the study were to measure the total organic carbon stock (OCst), total […]

ABSTRACT Microorganisms have a fundamental importance in agricultural ecosystems and may be influenced by several factors, including soil management. The aim of this study was to evaluate the effects of cropping systems and soil covers on the microbial community in soil cultivated with muskmelon (Cucumis melo L.). The experiment was conducted in a randomized complete block design with four replications. The treatments were arranged in a split plot design with cropping systems (no-tillage and conventional tillage systems) assigned to the […]

ABSTRACT The diversity of methods for heavy metal extraction from soils complicates comparison of results used by environmental agencies to establish quality reference values. The aim of this study was to evaluate three soil digestion methods regarding the solubilizing capacity of Ba, Cr, Cu, Fe, Mn, Ni, Pb and Zn, and to propose a standard method to establish Quality Reference Values (QRVs) for Brazilian Histosols. Twenty soil samples were selected to evaluate the USEPA 3051, USEPA 3051A and Aqua Regia […]

ABSTRACT The removal of original vegetation for crops and pasture production and then followed by natural regeneration is a standard practice in the Atlantic Forest, which has produced patches with different degrees of degradation and regeneration across the landscape. The aim of this study was to evaluate the effects of replacement of native forest by pasture and natural regeneration of vegetation on soil and on soil organic matter (SOM) dynamics in the dry and rainy season in an Atlantic Forest […]

ABSTRACT Solute transport parameters can be determined in miscible displacement experiments, usually performed in columns with disturbed (sieved) soil samples. Experiments with undisturbed samples are uncommon, due to the difficulty of taking undisturbed samples at the size required for these experiments. Structural alteration of the disturbed material implies modifications in the pore geometry that determines hydraulic properties, including hydraulic conductivity and retention and properties related to miscible displacement. An existing model for prediction of breakthrough curves based on retention properties […]

ABSTRACT The use of chemical methods to assess the soil organic nitrogen (N) potentially available to plants is not a common practice in Brazil. However, associated with others, this tool might improve efficiency in the use of waste and nitrogen fertilizers. In our study, chemical methods were tested to assess potentially available soil N in samples of 17 representative soils of the western plateau of the state of São Paulo (10 Oxisols and 7 Ultisols). Available soil N was extracted […]

ABSTRACT Rhizobia and associative bacteria promote growth in rice plants (Oryza sativa L.) through a series of mechanisms, but most studies on inoculation have been performed based on inoculation with these bacteria in a separate or singular manner. The objective of this study was to assess the efficiency of single/isolated inoculation and inoculation combined with symbiotic rhizobia from forage legume and with Azospirillum brasilense on promoting growth and the root colonization process in wetland rice. Two rhizobia among four isolates […]

ABSTRACT Mehlich-1 soil extract is currently used in Rio Grande do Sul (RS) and Santa Catarina (SC) States, in Brazil, to evaluate soil phosphorus available to plants and Mehlich-1 is sensitive to soil buffering capacity. This limitation is overcome partly by soil separation into buffering classes based on soil clay content. However, soil clay content has some technical and operational limitations, such as the underestimation of soil clay levels in soils under no-till. The aim of this study was to […]