In the conventional tillage system the soil is mobilized, incorporating and distributing crop residues and fertilizers in the arable layer. In no-tillage systems, however, where no soil mobilization occurs, lime and fertilizers are applied on the soil surface, which combined with the maintenance of crop residues cover favor the formation of a gradient of nutrient and organic matter concentration in the superficial soil layer. In the present study it was evaluated the effect of these two tillage systems on the […]

Tillage and plant species that compose the soil management and crop rotation systems have a pronounced effect on soil physical quality, especially on aggregate stability. This study aimed to evaluate the degree of aggregate stability of a soil cultivated under reduced tillage (RT) and conventional tillage (CT) using distinct summer cover crops. Two experiments were carried out in Chapecó, State of Santa Catarina, Brazil on a Hapludox under RT (1993-1998) and CT (1994-1998). Five crop systems were evaluated in each […]

The spatial variability of physical and chemical attributes of Latosols (Oxisols) cultivated with sugarcane was assessed. The study was carried out in a 90 ha area in the surroundings of Jaboticabal, São Paulo State, Brazil (21 º 15 ‘ S and 48 º 18 ‘ W). A 50 m regular grid was projected onto the experimental area. Soil samples were obtained at each 50 m grid point (421 points) from the 0 to 0.20 m and from the 0.60-0.80 m soil layers. Organic matter, pH, P, K+, Ca2+, Mg2+, H + Al, CEC, soil […]

Cover crops along with proper soil management recover or maintain soil physical properties such as aggregation. The objective of this study was to determine the effect of cropping systems, cover crops, and soil organic matter (SOM) content on the temporal variation of soil aggregation in an Hapludalf in its natural state and under different cropping systems. The experiment was conducted at the experimental station of the Soil Department of the UFSM, Brazil. Undisturbed soil samples were collected in 60 day-intervals throughout […]

Chisel plowing in-between rows of sugar cane ratoon, associated with fertilizer and harrowing (triple cultivation) is a common practice to reduce soil compaction, but little is known about its effects on ratoon rooting. The purpose of this study was to evaluate the effects of post-harvest chisel plowing on the physical properties of an Oxisol, root distribution, and yield. The experiment was set up in an Arenito Caiuá Soil and used the third ratoon of RB72454 sugar cane variety. The treatments […]

The soils of the Submiddle São Francisco River Valley are generally sandy, with low nutrient retention capacity. Since they are located in a semi-arid area, they are very poor in organic matter (OM) and as a consequence are deficient in nitrogen, which limits agricultural production. Thus, the use of legumes as green manure may overcome this problem because it adds carbon and nitrogen to soil. The study comprised two experiments with legumes intercropped with irrigated grape (Vitis vinifera) in a […]

Shear soil strength is an important dynamic property of the soil, as well as the state of soil consistence concerning the structure behavior of agricultural soils, which are mostly being ignored in research into the influence of use and management. This fact has been contributing to the perennial problem of fallacious strategies, causing degradation of the physical and mechanical soil properties. This study aimed at an evaluation of the shear soil strength of a dystrophic Red Latosol submitted to conventional […]

Widespread marketing technologies recomend the use of high doses of chemical fertilizers and the control of pests and diseases to maintain the productive potential of farms. This affects the sustainability of the coffee agroecosystem, creating a total dependence of industrialized products. The objective of this study was to compare the alterations of some chemical, physical, and microbiological characteristics of a Typic Hapludox from the region of Santo Antônio do Amparo (Minas Gerais State, Brazil), in agroecosystems of “organic coffee”, “in […]

Soil organic matter and its different pools have key importance in nutrient availability, soil aggregation, and in the greenhouse gas fluxes between the earth surface and the atmosphere. The objectives of this study were: a) to evaluate the effect of maize production systems under organic and mineral fertilization on total organic carbon (TOC) and total nitrogen (TN) stocks and on organic carbon pools (C) in an Acrisol; and b) to estimate the contribution of these systems in the atmospheric CO2 […]

This study was undertaken in Campos dos Goytacazes, northern State of Rio de Janeiro, based on soil samples of a vertic Fluventic Eutrochrepts, which had been cultivated with sugarcane for several decades. In one situation, the crop had been cultivated for 55 years without burning the residues at harvesting. On another sugarcane plantation, harvest residues had been burned, and vinasse inputs applied by sprinkle irrigation at a rate of 120 m3 ha-1 yr -1 during 35 years. Soil samples were collected from the soil layers […]