Herbivore exclusion stabilizes alpine grassland biomass production across spatial scales

There is growing evidence that land-use management practices such as
livestock grazing can strongly impact the local diversity, functioning and
stability of grassland communities. However, whether these impacts depend
on environmental condition and propagate to larger spatial scales remains
unclear. Using an 8-yr grassland exclosure experiment conducted at nine
sites in the Tibetan Plateau covering a large precipitation gradient, we
found that herbivore exclusion increased the temporal stability of alpine
grassland biomass production at both the local and larger (site) spatial
scales. Higher local community stability was attributed to greater
stability of dominant species, whereas higher stability at the larger
scale was linked to higher spatial asynchrony of productivity among local
communities. Additionally, sites with higher mean annual precipitation had
lower dominant species stability and lower grassland stability at both
spatial scales considered. Our study provides novel evidence that
livestock grazing can impair grassland stability across spatial scales and
climatic gradients.