Uso de VESS e propriedades físicas para identificar os efeitos da silagem na qualidade do solo

Abstract

The southwestern Paraná region is characterized by being composed of small farms, and most perform dairy farming. Silage in many of these rural properties is the main forage food, which is very important during crop season forage shortage. In addition, the harvesting operation of the corn plant for silage may cause soil compaction. The aim of this study was to evaluate if silage operations decrease soil quality through compression and to evaluate whether millet as a cover crop may improve soil quality after a crop term. The trial was carried out in 2015 on a rural property of Itapejara D’Oeste, Southwest region of Paraná. Two different fields composed the study: the first one with 2 ha (field 1), with silage production and subsequent sowing of millet, and the second one with 1 ha (field 2) used for silage for the first time. The treatments were: field 1 - post-silage and post-millet, and field 2 - pre and post silage. Soil samples with undisturbed structure were collected at depths of 0-5, 5-10, 10-15, 15-20 cm and performed the visual assessment of soil structure. In field 1, the soil density decreased after the cultivation of millet from 1.5 Mg m-3 to 1.31 Mg m-3. In field 2, the density after silage increased from 1.13 Mg m-3 to 1.26 Mg m-3. The macro values went from 0.11 m3m-3 to 0.16 m3m-3 and micro from 0.49 m3m-3 to 0.46 m3m-3. The VESS was positively correlated with the physical, the highest scores (Qe) coincided with the highest densities, higher micro m values, lower values of total porosity and macro.