The diffusive flux (diffusion) is the main form of zinc transport in soil, due to its low concentration in solution. This work aimed to evaluate the diffusion of Zn in samples of three soil types: a loamy texture Dark-Red Latosol (LE), a medium texture Red-Yellow Podzolic (PV), and a sandy texture Red-Yellow Latosol (LV). The diffusion was assessed in samples with the natural pH for the three soil samples and at pH 5.40 for the LE and 6.00 for the […]

This paper describes a technique that retrieves soil moisture from monopolarized SAR data. The technique uses SAR data obtained by the Japanese Earth Resources Satellite (JERS-1) and two empirical models. One relates the backscatter coefficient with the complex permitivity (Dubois’s model), and the other relates the complex permitivity with soil parameters such as soil moisture (Hallikainen’s model). First, the SAR data were calibrated to obtain the backscatter coefficient and the Dubois’s model was inverted to achieve the complex permitivity. The […]

Aggregate stability has been measured by wet sieving, water dropping and sonication. The objective of this study is to propose an index (energy – level based index) to express aggregate stability in A and B horizon aggregates of Dusky Red Latosol and Structured Dusky Red Earth. Aggregates from 4.76 to 7.93 mm were submitted to sonication at increasing energy levels. A dispersion ratio (< 0.053 mm aggregate + particle fraction/total aggregate mass) was plotted against energy levels, for each sample. […]

Aiming to evaluate the influence of the clay fraction mineralogy on the physical properties of Latosols (Oxisols) from southeastern Brazil, seven Latosols, representative of this group, were selected from the states of Minas Gerais and Espírito Santo, having distinct morphological features associated with soil structure. The sampling of soils was performed in the latossolic B horizon, with disturbed and undisturbed samples being collected. Chemical, physical and mineralogical characterizations were performed in the laboratory. Regression and correlation analyses taking into account […]

The spectroscopic characterization of humic substances in soil has been widely used. However, few studies have been carried out concerning the pedology of tropical soils using such technique. Humic acids (HA) extracted from contrasting horizons of a Red Yellow Latosol and a Podzol, on the highlands of the Serra do Brigadeiro, Araponga, Minas Gerais, were characterized by means of Fourier Transformed Infrared Absorption Spectroscopy (FTIR) and TD analysis. The spectra indicated qualitative differences between the HA extracted from differing soils, […]

The adverse effects of the heavy metals on all living forms make rehabilitation of heavy metal-contaminated soils very difficult. In this paper, the effects of seedling inoculation with arbuscular mycorrhizal fungi (AMF) on post-transplant growth and metal uptake of five woody species: (Senna multijuga (L.C. Rich.) Irwin et Barneby (cássia verrugosa), Luehea grandiflora Mart. et Zucc. (açoita-cavalo), Enterolobium contortisiliquum (Vell.) Morong (tamboril), Albizia lebbeck (L.) Benth. (albizia) and Senna macranthera (Collard.) Irwin et Barneby (fedegoso)) in soil mixes containing increasing […]

Soil pans caused by tillage operation may restrict root growth thus reducing yield. Physical properties of soil such as bulk density and soil strength have been used as parameters for management decision in order to promote root growth. This work was carried out to evaluate the relationship among these soil parameters and root growth, in a 7 year field experiment with five soil tillage systems and soybean (Glycine Max L.). The tillage systems combined summer and autumn tillage with disk […]

The amount and distribution of carbon, nitrogen, and sulfur in whole soil and in particle-size fractions were analyzed in two clayey Dark Red Latosols (LE1 and LE2). LE1 (forest as natural vegetation), from Cordeirópolis, São Paulo, cultivated with citrus since 1982 receiving two lime treatments, control and 18 t ha-1 applied twice in 1983 and 1994. Since 1976, LE2 (cerrado as natural vegetation) from Planaltina, Federal District (cerrado region), was cultivated with different crops (wheat, soybean, rice and sorghum) sown […]

In addition to improving chemical attributes of the soil, such as pH, exchangeable Ca and available Si, calcium silicate fertilization in soils with low soluble silicon (Si) can also affect rice yield due to a greater resistance to lodging and increased photosynthetic area. The objective of this study was to evaluate Si availability in soils from the Brazilian savannas (Cerrado). The experiment was carried out in a greenhouse using upland rice. The treatments consisted of 5 Si rates (0, 120, […]

This study aimed to evaluate the relationship between the mineralogical constituents of clay fraction and the development of micro and macrostructure of Latosols (Oxisols) from southeastern Brazil. For that purpose, samples of oxic horizons were obtained from seven Latosols representative of this group, from Minas Gerais and Espírito Santo states. The different soil samples were submitted to morphological, chemical, physical, mineralogical and micromorphological characterizations. From the different results it was possible to conclude that kaolinite and gibbsite are the main […]