Globally, plant-soil feedbacks are weak predictors of plant abundance

Authors: Reinhart, Kurt; BAUER, JONATHAN - Miami University - Ohio; MCCARTHY-NEUMANN, SARAH - Alma College; MACDOUGALL, ANDREW - University Of Guelph; HIERRO, JOSE - Universidad Nacional De La Pampa; CHIUFFO, MARIANA - Universidad Del Comahue; MANGAN, SCOTT - Arkansas State University; HEINZE, JOHANNES - University Of Potsdam; BERGMANN, JOANA - Berlin-Brandenburg Institute Of Advanced Biodiversity Research (BBIB); JOSHI, JASMIN - Berlin-Brandenburg Institute Of Advanced Biodiversity Research (BBIB); DUNCAN, RICHARD - University Of Canberra; DIEZ, JEFF - University Of Oregon; KARDOL, PAUL - Swedish University Of Agricultural Sciences; RUTTEN, GEMMA - University Of Bern; FISCHER, MARKUS - University Of Bern; VAN DER PUTTEN, WIM - Netherlands Institute Of Ecology; MARTIJN BEZEMER, THIEMO - Netherlands Institute Of Ecology; KLIRONOMOS, JOHN - University Of British Columbia

Submitted to: Ecology and Evolution
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/11/2020
Publication Date: 1/27/2021
Citation: Reinhart, K.O., Bauer, J.T., Mccarthy-Neumann, S., Macdougall, A.S., Hierro, J.L., Chiuffo, M.C., Mangan, S.A., Heinze, J., Bergmann, J., Joshi, J., Duncan, R.P., Diez, J.M., Kardol, P., Rutten, G., Fischer, M., Van Der Putten, W.H., Martijn Bezemer, T., Klironomos, J. 2021. Globally, plant-soil feedbacks are weak predictors of plant abundance. Ecology and Evolution. 11(4):1756-1768. https://doi.org/10.1002/ece3.7167.
DOI: https://doi.org/10.1002/ece3.7167

Interpretive Summary: A long-standing challenge in the field of ecology is to reveal which factors regulate plant abundance, coexistence, and community composition. Plants often accumulate soil biota which have host-specific negative impacts and may strongly affect plant performance and mixtures of vegetation. Such plant-soil feedbacks have been widely studied, but results vary by study on their relationship with plant species abundance in the field. ARS researchers in Miles City, Montana, in collaboration with researchers from nine countries, conducted a synthesis of experiments from tropical forest to semiarid grasslands. Across experiments, results indicate a tendency for a positive correlation between plant field abundance and feedback across plant functional types and variation by functional type. The results provide quantitative support that plant abundance has a general, albeit weak, positive relationship with plant-soil feedback across ecosystems thereby suggesting harmful soil biota tend to accumulate around and disproportionately impact rare plants more than abundant plants.

Technical Abstract: Plant-soil feedbacks (PSFs) have been shown to strongly affect plant performance under controlled conditions, and PSFs are thought to have far reaching consequences for plant population dynamics and the structuring of plant communities. However, thus far the relationship between PSF and plant species abundance in the field is not consistent. Here, we synthesize PSF experiments from tropical forests to semiarid grasslands, and test for a positive relationship between plant abundance in the field and PSFs estimated from controlled bioassays. We meta-analyzed results from 22 PSF experiments and found an overall positive correlation (0.12 = urn:x-wiley:20457758:media:ece37167:ece37167-math-0001 = 0.32) between plant abundance in the field and PSFs across plant functional types (herbaceous and woody plants) but also variation by plant functional type. Thus, our analysis provides quantitative support that plant abundance has a general albeit weak positive relationship with PSFs across ecosystems. Overall, our results suggest that harmful soil biota tend to accumulate around and disproportionately impact species that are rare. However, data for the herbaceous species, which are most common in the literature, had no significant abundance-PSFs relationship. Therefore, we conclude that further work is needed within and across biomes, succession stages and plant types, both under controlled and field conditions, while separating PSF effects from other drivers (e.g., herbivory, competition, disturbance) of plant abundance to tease apart the role of soil biota in causing patterns of plant rarity versus commonness.