Effect of the application of two plant residues on the density and porosity of soils subjected to compaction

Abstract

This study evaluates the effect on the density and porosity of three differently textured soils when they were subjected to different degrees of compaction, following the addition of two crushed vegetable residues, palm leaf and hay straw. Mixtures were prepared incorporating the plant residues to each soil following the proportions: 10%, 20%, 30% and 40% (<em>V</em>/<em>V</em>). To quantify the incidence of compaction on physical properties, cylindrical PVC containers were used. The soil-waste mixtures were subjected to pressures of 0 (kg/cm<sup>2</sup>), 1.12 (kg/cm<sup>2</sup>) and 2.24 (kg/cm<sup>2</sup>). The results obtained showed that the addition of the residues reduces the apparent density in the three soils, with the use of hay straw having the greatest decrease. As an example, in soil 1, without applying compaction, the apparent density varies with the application of palm leaf from 1685 (kg/m<sup>3</sup>) to 890 (kg/m<sup>3</sup>) and with the straw reaches values of 781 (kg/m<sup>3</sup>).