During timber exploitation in forest stands harvesting machines pass repeatedly along the same track and can cause soil compaction, which leads to soil erosion and restricted tree root growth. The level of soil compaction depends on the number of passes and weight of the wood load. This paper aimed to evaluate soil compaction and eucalyptus growth as affected by the number of passes and wood load of a forwarder. The study was carried out in Santa Maria de Itabira county, […]

This study had the objective of characterizing the main soil types cultivated with melon, based on physical features, in the Apodi Tableland, state of Rio Grande do Norte, to provide basic information for an adequate soil and crop management. Three soil types were studied, in September 2003: Cambissolo Háplico Ta eutrófico típico – CXve (Typic Haplocambids), Latossolo Vermelho-Amarelo eutrófico típico – LVAe (Typic Eutrotorrox) e Argissolo Vermelho distrófico arênico – PVd (Arenic Kandiustults). A general analysis of the soil physical […]

The improvement in the structural soil quality under continuous no-tillage occurs concomitantly to soil (re)acidification. Surface compaction can sometimes occur, owing to machinery traffic, which has to be corrected by soil tilling. In a 12-year experiment under different soil management systems we evaluated the time it takes to recover the initial soil physical attributes that are affected by soil tillage by the occasion of lime reapplication. The experiment was set up on a Rhodic Paleudult (Ultisol) at the Agronomical Experimental […]

Selective logging may become a form of sustainable use of Amazon forest ecosystems since most part of the forest biomass is maintained and the impacts on the exploited area are lower than in comparison to those under other land uses. The objective of this study was to evaluate the effects of selective logging on some soil physical characteristics. The study area lies about 80 km north of Manaus and the vegetation is a humid tropical rainforest. Seven to ten trees/ha (DAP > 55 cm) […]

Both soil conservation and crop productivity may negatively be affected by changes caused to soil characteristics by management techniques. The objective of this study was to evaluate the influence of soil tillage on soil physical attributes and organic carbon contents. The experiment was carried out over a period of 17 years in Eldorado do Sul County (RS) in a loamy Acrisol under different management systems: conventional tillage, reduced tillage and no-tillage, using vetch-maize in crop succession. An area of native […]

Different sugarcane management systems on soils of coastal tablelands can cause alterations in their original soil structure. Effects of the different sugarcane management systems on the properties of a cohesive Yellow Argisol were studied in four areas of the Triunfo sugar mill in Alagoas State, Brazil. The treatments consisted of a site with and without cultivation irrigation each, one site with vinasse application and another under undisturbed native forest. Samples were collected at depths of 0-0.2, 0.2-0.4 and 0.4-0.8 m to […]

This study was carried out from 1994 to 1998 in the Agronomy experimental area at the University of Cruz Alta – UNICRUZ, Cruz Alta, State of Rio Grande do Sul, Brazil to evaluate the influence of five soil management systems on bulk density, porous space (total porosity, macro and microporosity) of an clayey Rhodic Hapludox, as well as their effect on soybean, wheat and corn yield. The experiment had a completely randomized block design with four replications. The following management […]

Soil tillage and crop systems have significant influence on the soil structure, affecting water and air flow. The objective of this study was to evaluate the effects the management has on the soil properties of a Hapludox cultivated with maize intercropped with summer cover crops. Two experiments were carried out in Chapecó, State of Santa Catarina, Brazil under reduced tillage (RT) from 1993 to 1998 and conventional tillage (CT) from 1994 to 1998. Three cropping systems were evaluated under each […]

In soils with naturally favorable characteristics for cultivation, conventional tillage degrades the physical soil properties, since this management system causes the rupture of aggregates, soil compaction, and eliminates soil cover. No-tillage, on the other hand, maintains soil cover and improves physical properties, but consolidates the surface layer. Our study was conducted on a Haplumbrept soil, from May 1995 to April 2001. Five soil tillage treatments were used: conventional tillage crop rotation (CTR), conventional tillage crop succession (CTS), no-tillage crop rotation […]

High phosphorus (P) sorption capacity is a typical feature of oxidic oxisols. P is mainly sorbed by inner-sphere complex affecting charge balance, particle dispersion and, consequently, water-soil relationship. The objective of this study was to evaluate the effect of P sorption on physical and hydric properties of samples of a Typic Hapludox, from Campos Mantiqueira Region (Minas Gerais, Brazil). Disturbed and undisturbed soil samples, from 0-0.03 and 0.27-0.30 m depth, were saturated in pure water or P solution to reach […]