Araucaria araucana is an iconic long-lived endangered tree species
exclusively distributed in Southern Chile and Argentina. Araucaria
forest ecosystems provide a myriad of ecosystem benefits to local
aboriginal Mapuche-Pehuenche communities. Among the main current threats
for Araucaria forests are the increasing frequency and severity of
wildfires and overgrazing. This study evaluates the effect of
uncontrolled livestock grazing on soil quality indicators linked to
critical functions relevant to forest regeneration and ecosystem service
provision. We also aim to determine a set of soil quality indicators
that are sensitive enough to grazing pressure, so they are useful as
early indicators of degradation or the effectiveness of restoration
practices. This study evaluated twenty soil quality indicators in two
contiguous degraded forest areas with contrasting grazing pressure. We
observed a substantial shift in forest structure, a reduction in tree
coverage on the overgrazed sites. Overgrazing has produced significant
deterioration of most soil physical, chemical, and biological quality
indicators making soil conditions less suitable for seed germination and
sapling establishment. We also observed an alteration in C, N, and P
biogeochemical pools. Besides, soil physical indicators alterations
suggest changes in these soils' hydrological behavior, potentially
reducing water storage, availability, and increasing runoff. We show
that uncontrolled grazing in native protected areas degrades soils and
forest health, restricting forest regeneration and potentially
accelerating erosive processes. Our results emphasized the need for an
improved conservation plan for these forests that systematically
evaluates and monitors livestock grazing and all its direct and indirect
effects, including soil quality.