The objectives of this study were to use kriging indicators to generate a representation of soil properties expressed by numeric attributes, to assess the uncertainty in estimates, and to model the uncertainty propagation generated by the fuzzy procedures of map algebra. The studied attributes were exchangeable potassium (K) and aluminum (Al) contents, sum of bases (SB), cationic exchange capacity (CEC), base saturation (V), and total sand content (TST), extracted from 222 pedologic profiles and 219 extra samples, located in Santa […]

The objectives of this work were to generate a representation of soil properties expressed by categorical attributes by kriging indicator; to assess the uncertainty in estimates, and to model the uncertainty propagation of map algebra by means of boolean procedures. The studied attributes were potassium (K) and aluminum (Al) exchangeable contents, sum of bases (SB), cationic exchange capacity (CEC), base saturation (V), texture (Tx) and relief classes (RC), effective soil depth, internal drainage, and stoniness and/or rockiness, extracted from 222 […]

A greenhouse experiment was carried out to evaluate the effect of sulphur (S) inoculated with Acidithiobacillus on phosphorus (P) availability from natural phosphate (NP) using different fertilizer application methods on yam bean (Pachyrhizus erosus) grown in a “Tableland Forest” soil (Podzol Hydromorphic dystrophic) of the “Zona da Mata” in the State of Pernambuco, Brazil. Plants were inoculated with rhizobia strains (NFN 747 and NFB 748) and control treatments added without rhizobia inoculation. The P treatments were: (1) NP pelleted with […]

The state-space approach is used to evaluate the relation between soil physical and chemical properties in an area cultivated with sugarcane. The experiment was carried out on a Rhodic Kandiudalf in Piracicaba, State of São Paulo, Brazil. Sugarcane was planted on an area of 0.21 ha i.e., in 15 rows 100 m long, spaced 1.4 m. Soil water content, soil organic matter, clay content and aggregate stability were sampled along a transect of 84 points, meter by meter. The state-space […]

Most of the intensely cultivated soils of South Brazil are Brown and Red Ferric Latosols developed from basalt. Typical profiles of these two classes have brown and red hues, respectively, but polychromatic profiles with brown hues in the surface horizons and reddish hues in the subsurface horizons (formerly denominated Brown/Reddish Latosols) also occur. Exact color parameters that separate Brown and Red Latosols are not yet defined in the Brazilian Soil Classification System. All these soils are clayey and have high […]

An adequate nitrogen fertilizing management throughout a crop cycle of bell pepper (Capsicum annuum L.) is problematical for lack of an index of available soil N and because the chemical leaf analysis, on the other hand, is a slow diagnosis method. The experiment was conducted in a plastic tunnel of the Dept. of Natural Resources/Soil Science, of FCA/UNESP, Botucatu, São Paulo State, in pots, with the objective to assess the nitrogen sufficiency index (NSI). Calculations consisted in chlorophyll meter readings […]

A long-term field trial was carried out in the Jaboticabal county, São Paulo State. with the objective of estimating production system effects on the soil organic carbon and soil organic matter fractions. The tested treatments were corn under conventional sowing in the summer and no-tillage in the winter (C-Mi-P), maize under direct sowing in the summer and no-tillage in the winter (D-Mi-P), maize under direct sowing in the summer, Mucuna aterrina as green manure in the winter (D-Mi-Mu), maize under […]

Leaf litter decay rates and N and P fluxes of tree species are different in pure and mixed stands because the decomposition process is not only defined by the quality of the substrate, but of the microenvironment (forest production systems) also. The objetive of this work was to estimate the decomposition rate and N and P release from leaf litter of native forest species planted under two different systems. Twenty two year-old mixed and pure stands of six hardwood species […]

In soils constructed after coal mining, superficial contamination with pyrite coal residues causes acidification, accelerates the mineral weathering, increases Al and Mn contents, and base leaching. The present work evaluated chemical characteristics, clay content and mineralogy, and the spatial variability for some of these characteristics in three constructed soil areas after surface coal mining in Lauro Müller, Santa Catarina State, Brazil. The selected areas present differences in their topographic soil construction. The first area, Juliana Mine (MJ), was constructed in […]

The aim of this work was to evaluate the relations between landforms and soil erosion of an Oxissol with geostatistical techniques in Jaboticabal (SP), Brazil, in two landform models: concave and linear. Soil samples were collected from both landforms at a depth of 0-20 cm, in a regular 50 x 50 m mesh of seven transects, at totally 412 grid points within an area of 93 ha. Physical and chemical properties were determined at each point and used to estimate the soil erodibility by indirect […]