Morphometric Studies of Compacted Layers of Oxisols Under Different Uses in the Western Region of Bahia State

Abstract

The presence of densified or compacted layers is common in western Bahia State cultivated soils, which may hinder agricultural operations. This work evaluated theses layers in representative soils in six plots in this region, comparing the effects of different cultivation systems. The selected samples were analyzed by micromorphological techniques and sand grain morphometry. It was found that the porosity was greater in the soils under native savanna, and the pore distribution was unequal among the systems. The cotton area showed a trend to reduced porosity values, while in the no-till and the common beans’ areas, the values were intermediate. Coarse sand grain morphometry results allowed the separation of three groups, one with irregular and rough grains, a second with rounded grains and the last with intermediate types, the second one being dominant. For the medium-size sand grains, the last group was dominant. The morphometric analysis showed a similar pattern among the samples, implying that the soils may be descendant from the same parent materials. It implies that the differences in the results of the micromorphological analyses may be attributed to the soil management practices in the areas.