Dataset from: Warming effects on grassland productivity depend on plant diversity

Aim: Climate warming and biodiversity loss both alter plant productivity,
yet we lack an understanding of how biodiversity regulates the responses
of ecosystems to warming. In this study, we examine how plant diversity
regulates the responses of grassland productivity to experimental warming
using meta-analytic techniques. Location: Global Major taxa studied:
Grassland ecosystems Methods: Our meta-analysis is based on warming
responses of 40 different plant communities obtained from 20 independent
studies on grasslands across five continents. Results: Our results show
that plant diversity and its responses to warming were the most important
factors regulating the warming effects on plant productivity, among all
the factors considered (plant diversity, climate and experimental
settings). Specifically, warming increased plant productivity when plant
diversity (indicated by effective number of species) in grasslands was
lesser than 10, whereas warming decreased plant productivity when plant
diversity was greater than 10. Moreover, the structural equation modelling
showed that the magnitude of warming enhanced plant productivity by
increasing the performance of dominant plant species in grasslands of
diversity lesser than 10. The negative effects of warming on productivity
in grasslands with plant diversity greater than 10 were partly explained
by diversity-induced decline in plant dominance. Main Conclusions: Our
findings suggest that the positive or negative effect of warming on
grassland productivity depends on how biodiverse a grassland is. This
could mainly owe to differences in how warming may affect plant dominance
and subsequent shifts in interspecific interactions in grasslands of
different plant diversity levels.