Context-dependent effects of livestock grazing on forest attributes and ecosystem multifunctionality in Nothofagus forests

Abstract

Forests under livestock grazing sustain important ecosystem services but face potential trade-offs between production and ecological integrity. While the effects of grazing on individual forest attributes are well documented, their integrated consequences remain poorly understood, particularly in temperate forest ecosystems. We evaluated the combined influence of livestock grazing intensity and canopy cover on individual attributes and ecosystem multifunctionality in native Nothofagus forests of Tierra del Fuego, Argentina. Across eight ranches spanning two agroecological regions (Ecotone and Mountain Range), we quantified forest regeneration, understorey richness and biomass, and soil properties, integrating them into a multifunctionality index. Using generalized linear mixed models, we found strong context-dependence: in the Mountain Range, higher grazing intensity reduced seedling and sapling density, organic matter content, coarse woody debris, and overall multifunctionality. In the Ecotone, these effects of livestock use intensity were attenuated, and canopy cover diminished sapling density and multifunctionality, but moderate cover enhanced understorey. Our results extend multifunctionality research from grazed grasslands to grazed temperate forests and show that ecological responses and trade-offs vary across landscape units. We conclude that the Mountain Range is more vulnerable to grazing, requiring stricter management, whereas the Ecotone retains greater capacity to sustain multifunctionality under controlled livestock use intensity. These findings underscore the importance of regionspecific silvopastoral strategies that reconcile food production with forest conservation in southern Patagonia and comparable temperate forest landscapes worldwide.