The organic acids from the organic matter decomposition, root exudation and microbial activity, play an important role on physical and chemical soil conditions. However their efficiency is conditioned to the quality and kind of organic acids and interactions with the soil mineral surface. The aim of this study was to evaluate the effect of humic and organic acids of high and low molecular weight on the physical and chemical properties of B horizons of four Oxisols and one Plinthustult, and […]

The knowledge of the pressure levels that can be applied to the soil under different weed management system (WMS) is importante for coffee plantations management. The objective of this study was to evaluate the influence of different weed management systems on the susceptibility to compaction of a Red-Yellow Latossol (Oxisol) (LVA) using soil support capacity (CSC) models. This study was carried out at the Epamig Research Farm in Patrocínio, state of Minas Gerais, Brazil, in a coffee plantation using Ruby […]

In the region of Janaúba, northern Minas Gerais State, Brazil, banana yields are high due to the highly technical agriculture of the region, with intensive use of fertilizers and systematic plant disease and pest control. However, farmers frequently report a decline in banana yields, particularly when water from deep wells is used for irrigation. We therefore studied the effect of irrigation water from wells and from the Gorutuba River on soil chemical characteristics of areas with banana cultivation. Soil samples […]

The degradation of soils with high sand content, in the southwest of the state of Rio Grande do Sul, is due to the vegetal cover withdrawal, forming sandy areas called “areais”, which pose a risk to animal husbandry and the prairie ecosystem. A technique of revegetation with cover crops such as Avena strigosa Schieb. and Lupinus albescens H. et Arn., was developed to reduce the soil particle movement by eolic erosion. The experiment was carried out on a Quartzipsament soil, […]

In the middle Rio Doce Valley, with strong seasonal dry-wet alterations, Latosols, Cambisols and Argissols coexist, with greater chemical fertility in the latter. General regional observations indicate a certain mineral reserve in Latosols, which gives them a “cambic” character, as well a “Latosolic” morphology in the Cambisols. In this study, we analyzed the genesis and pedological characteristics of Latosols, associated Cambisols and an Argisol in two toposequences from the Desidério catchment, in the Upper Plateau of the Suaçui Pequeno/Corrente Grande […]

The objective of this study was to evaluate the effect of the rainfall variability on the runoff and sediment amount in the Pipiripau river basin (A = 235 km2), in the Distrito Federal, Brazil. To represent the climatic variability of the historic precipitation series, 5 years were selected: the moistest, the driest, an average, and 2 years representing the standard deviations from the series (half-wet and half-dry). After the calibration of the model with basin rainfall and runoff data, each rainfall event was simulated […]

Boron (B) adsorption by soils affects its bioavailable contents and contamination potential. The objectives of this study were: (a) to investigate the effects of pH variation on B adsorption by topsoil and subsoil samples from an Anionic “Rhodic” Acrudox (RA), an Anionic “Xanthic” Acrudox (XA) – both with a positive balance of charge in Bw horizon – and a Rhodic Kandiudalf (RK); (b) to evaluate the ability of the Langmuir model of simulating the experimental results of B adsorption; and […]

Brazilian soil surveys are mostly outdated, with few details, usually based on discovery and recognition. This fact can be ascribed to the traditional, slow and expensive soil survey method, requiring a great number of field observations. Thus, faster and cheaper soil mapping techniques must be developed. The objective of this study was to characterize soil mapping units in the region of Ibaté and São Carlos, state of São Paulo, measuring slopes and altitudes, based on a digital elevation model (DEM). […]

Pedotransfer functions (PTFs) are useful tools to obtain estimates of soil physical properties such as the soil water retention curve (SWRC) and the soil resistance to penetration curve (SRPC), which are important inherent soil properties and difficult to measure. Most of the studies in the literature report PTFs only in relation to SWRC estimates. An important and necessary advance in this research area would be the development of PTFs for a simultaneous estimation of the SWRC and SRPC, which is […]

Soil management systems, with crops under no-tillage (NT), crops (soybean) in rotation with pastures under NT and permanent pastures (Brachiaria sp.), were evaluated for soil aggregation and aggregate stability. Three long-term experiments (9 and 11 years) in the state of Mato Grosso do Sul were sampled in the layers 0-5, 5-10 and 10-20 cm for determination of the aggregate stability in wet and dry sieving. The mean weight diameter (MWD) and the aggregate stability index (IAS) were calculated. In all experiments, the […]