Influence of compactation on chemical characteristics and physical-properties of soil samples cropped with bean (Phaseolus vulgaris, L.)

Abstract

Soil samples of an orthic Haplacrox (LR) and an ochrultic Typustalf (PVp) were used In this experiments, including the A and B2 horizon, subject to compaction. They were confined in 3,8 1 pots, and incubated during 80 days (cultivated with beans during 67 days), with a soil water tension between 100 to 300 mbars. The physical determinations showed an increase of the soil bulk density, and a decrease of the total porosity and the saturated hydraulic conductivity. The micropores and bloqued pores increased in LR an decreased in PVp. The soil samples of the LR-B2 were less susceptible to changes due compaction, while of the PVp-B2 were the most susceptible, followed by those of the LR-A1 and the PVp-Ap. The chemical data showed tendencies of increase of the carbon level in the A horizon without fertilizer, and decrease with fertilizer, on LR and PVp with compaction increase. They also showed decrease of the available P and increase of the exchangeable Al with fertilizer, and reduction of the exchangeable Mg without and with fertilizer in the A horizon of both soils, as the compaction was increased.