Efeito da escarificação na porosidade e densidade de um solo sob pastagem.

Abstract

Soil compaction can be considered one of the main factors that can accelerate soil degradation on pasturelands. When the soil compaction takes place; some soil physical attributes are changed, such as soil density and soil porosity. Aiming to reverse the soil degradation process and to set a good soil condition for pasture recuperation, the soil scarification management can be a good option because this technique maintains a good vegetal soil covering. The objective of this work was to evaluate soil porosity and soil density of a soil under pasture, aiming to its degradation recovering. To achieve this objective was installed an experiment in an area under pasture, cultivated with Brachiaria decumbens in the Instituto de Zootecnia in Nova Odessa - SP, were was measured the soil penetration resistance in plots with scarification up to 25 cm deep and plots with no scarification. The data of soil density and soil porosity was obtained from undisturbed soil samples. These samples were taken 60 days after the scarification process. These samples were taken from 0 to 100 mm, from 100-200 mm, and from 200-300 mm deep. The data showed that the scarification process reduced the soil density and increased the soil porosity at the layer of 0-100mm deep. At the layer from 100-200 mm deep, the data did not show any significant changes on the properties measured. At the layer from 200-300 mm deep that data showed a reduction on the macroporosity. The scarification process did not affect the microporosity.