Biotic Interactions Shape Soil Bacterial Beta Diversity Patterns along an Altitudinal Gradient during Invasion.

Area of Science:

• Ecology
• Microbiology
• Plant Science

Background:

• Invasive plants threaten native species in mountain forest understories.
• Soil microorganisms may drive plant invasions, but invasion mechanisms are unclear.
• Understanding microbial community shifts during invasion along altitudinal gradients is crucial.

Purpose of the Study:

• To compare elevational patterns of soil bacterial beta diversity between invasive and native plants.
• To identify ecological processes driving bacterial community composition during plant invasion.
• To investigate the role of environmental filtering, co-occurrence, and assembly processes.

Main Methods:

• Comparative analysis of soil bacterial beta diversity along an altitudinal gradient in the Qinling Mountains.
• Assessment of species turnover and its contribution to beta diversity.
• Evaluation of community assembly processes, including environmental filtering and co-occurrence patterns.

Main Results:

• Species turnover was the primary driver of bacterial dissimilarity in both native and invasive communities.
• The contribution of species turnover to beta diversity decreased during invasion.
• Bacterial dissimilarities and turnover showed a binomial pattern with an altitudinal tipping point at 1413 m.
• Invasion led to decreased contributions of assembly processes and increased co-occurrence patterns.

Conclusions:

• Plant invasion shifts bacterial community assembly from niche-based processes to species interdependence.
• Invasive plants alter soil physiochemical characteristics, influencing bacterial biogeography along altitudinal gradients.
• Species interdependence, rather than niche partitioning, is key to the bacterial biogeography of invasive communities.