Data from: Increased precipitation attenuates shrub encroachment by facilitating herbaceous growth in a Mongolian grassland

Widespread shrub encroachment is profoundly impacting the structures and
functions of global drylands, and precipitation change is assumed to be
one of the most critical factors affecting this phenomenon. However, there
is little evidence to show how precipitation changes will affect the
process. In this study, we conducted a 6-year precipitation manipulation
experiment (-30%, ambient, +30%, and +50%) to investigate the effects of
precipitation changes on the growth of shrubs and herbaceous plants in a
shrub-encroached grassland in Inner Mongolia. We found that the increasing
precipitation significantly increased the mean height, coverage, and
aboveground biomass of herbaceous species, while the growth of shrub
species did not exhibit a significant response to precipitation changes.
With increasing precipitation, the relative coverage of shrubs decreased,
while that of herbs increased. The native dominant herbaceous plant
(Leymus chinensis) with more sensitive maximum photosynthetic rate to the
precipitation change, showed higher photosynthetic nitrogen use efficiency
and water use efficiency than those of the encroached shrub species
(Caragana microphylla) at high soil moisture contents, reflecting that the
ecophysiological characteristics of L. chinensis might provide it a
competitive advantage under increased precipitation. Our findings suggest
that increasing precipitation may slow down shrub encroachment by
facilitating herbaceous growth in Mongolian grasslands, and consequently
affect the forage value and carbon budget in these ecosystems.