Over 65% of drylands are used for grazing of managed livestock. Understanding what drives
grazing effects on the structure and functioning of rangelands is critical for achieving their
sustainability. We studied a network of 239 sites across Patagonian rangelands (Argentina),
which constitute one of the world´s largest rangeland area. We aimed to: i) evaluate how
aridity and grazing affect ecosystem structure and functioning, and ii) test the usefulness of
the landscape function analysis (LFA) indices (stability, infiltration and nutrient cycling) as
surrogates of soil functioning. Aridity decreased species richness and the cover of palatable
grasses, but increased the cover of palatable shrubs. Grazing pressure negatively impacted the
cover of palatable grasses and species richness, but did not affect the cover of shrubs. Aridity
had a direct and an indirect negative relationship with the LFA indices. Grazing pressure had
no direct effects on the LFA indices, but had an indirect negative effect on them by affecting
vegetation structure. The LFA indices were positively and negatively correlated with soil
organic carbon and sand contents, respectively, suggesting that these indices are useful
proxies of soil functional processes in Patagonian rangelands. Our findings indicate that
aridity and overgrazing have convergent effects on the structure and functioning of
ecosystems, as both promoted reductions in species richness, the cover of palatable grasses
and soil functioning. Rangeland management activities should aim to enhance species
richness and the cover of palatable grasses, as these actions could contribute to offset adverse
effects of ongoing increases in aridity on drylands.

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