Quality indicators of subsoiling with hydraulic excavator in sloping areas at two different soil moisture levels

Abstract

The recent adaptation of the use of the hydraulic excavator in the preparation of the soil in sloping areas presented satisfactory results, mainly due to the benefits provided by the increase of the sub-soiled area. However, the quality of its achievement in the field activity is not yet known and, therefore, the objective was to evaluate the quality of mechanized soil preparation by the hydraulic excavator sub-soiling rod, in two different soil moisture conditions, by means of quality indicators. For this, a complete randomized block design with two treatments and 12 replications was used. The response variables used to evaluate soil tillage quality were: furrow depth and width, mobilized soil area, furrow shape and clod quality index (IQT). The results show that moist soil resulted in higher average values for all variables, presenting higher sub-soiling quality, due to the higher volumetric humidity. The dry soil presented soil tillage quality standards, however, the IQT was high, causing non-conformities in the groove shape; this being the result related mainly to the fact that the excavator did not have furrow finishing devices. However, the subsoiling operation with the hydraulic excavator is considered suitable for use in areas with a slope of 17 to 27º. Therefore, the initiative / need for research and studies on new technologies is recommended to promote the reduction of IQT in dry periods and increase the effectiveness of field activity.