Effect of management change of a degraded pasture on the soil physical resilience in the Andean mountains of the Araucanía region

Abstract

Although there is a broad base of information about the negative effects of grazing on pastures and soil, there are few studies that recorded a positive change in soil functioning and pasture response. Such studies are relevant because they allow analyzing the impact of management strategies on the pasture and soil. The aim of this study was to evaluate the recovery of physical properties of an Andisol in the short term, after the implementation of sustainable pasture management. Soil samples were collected at 5 cm deep in an Acrudoxic Melanudand next to the Andes in grasslands under different grazing management in the last six years (Degraded Grassland: DG and Improved Grassland: IG) and in a site used as a control (Native Forest: NF). Chemical and physical properties as well as the mechanical and functional soil resilience were determined. Soils under pastures presented higher bearing capacity, penetration resistance and bulk density. Additionally, a decrease in coarse porosity and air conductivity was observed in soils under pastures when compared to the soil under NF, which reflects the structural differences of the soil when subjected to different uses. No significant differences were found but the observed trend showed an improvement in the physical attributes of IG when compared to DG due to changes in grazing management, expecting that these differences will be accentuated in a larger period of time.