Net plant interactions are highly variable and weakly dependent on climate at the global scale

Area of Science:

• Ecology
• Plant Community Ecology
• Global Ecology

Background:

• Plant-plant interactions, including competition and facilitation, are recognized drivers of community dynamics.
• Global patterns and climatic influences on these interactions remain poorly understood.

Purpose of the Study:

• To investigate global patterns of plant interactions.
• To assess the influence of climate on the net outcome of plant interactions in natural communities.

Main Methods:

• Assembled a global database of 10,502 empirical data pairs from scientific literature.
• Analyzed interaction outcomes across different plant performance indicators, interaction types, and biomes.

Main Results:

• Plant interactions varied significantly across indicators, types, and biomes.
• Competition was found to be more frequent than facilitation globally.
• Plant interactions exhibited weak latitudinal patterns and limited relationships with macroclimate.

Conclusions:

• Competition is a fundamental mechanism structuring plant communities worldwide.
• Local factors (microclimate, soil, disturbance) may be more critical than macroclimate in determining plant interactions.
• Further research should prioritize local environmental determinants of plant interactions.