The pasture agro-ecosystem reacted different to erosion (Fig. 3), demonstrating that vegetation cover has a protective effect by maintaining low levels of eroded soil. In addition, the roots improved the porosity and infiltration rates, thus limiting and controlling runoff development.
The factor alleged to cause these differences was land use; in the potato agro-ecosystem, uncovered soil favoured particle disaggregation and losses by surface runoff. The loss of structure generates changes like pore sealing or rapid saturation, finally expressed as low permeability (Table 1). Furthermore, farmers customarily prepared cultivable land in the slope's direction in order to avoid floods or humidity excess in the crops. This, in turn, favoured higher speeds of the surface runoff, thus progressing from a transport factor to a soil matrix detachment phenomenon, and this caused more severe erosion rates (Fig. 4).