The objective of this study was to evaluate the influence of different agricultural uses on alterations in the attributes of a medium-textured Latosol, in the region of cerrado and, in turn, on the formation of compacted and/or dense layers in the subsurface. In April, 1994, six sites were selected in the counties of Uberlândia and Monte Alegre de Minas, State of Minas Gerais, Brazil, where the soil was sampled in trenches: CC (Canadá Farm, cerrado vegetation); CP ( Canadá Farm, cultivated with the use of a central pivot); GC (Gaia Farm, cerrado vegetation); GPa (Gaia Farm, pasture); GP1 and GP2 (Gaia Farm, cultivated with the use of a central pivot). The soil was classified as Dark Red Latosol of medium texture and presented compacted and, or, dense layers in the subsurface, even in the areas under cerrado vegetation, with variations only in the value of bulk density and depth in which these layers appear. The cultivation caused modifications in relation to the cerrado areas. The area under pasture presented a behaviour very similar to that of the cerrado areas, except for the hardening of the surface. There was an increase in density in the subsuperficial layers, which may have been caused by the increase of the water-dispersed clay in the cultivated areas. The increase of the water-dispersed clay was caused by several factors, such as reduction of organic carbon and liming and increased PZC. There was a significant and positive correlation between SiO2 content and the percentage of water-dispersed clay, which contributed to the formation of compacted layers in this soil under different uses.
Compaction; densing; liming; physics characteristics; chemical characteristics