The next frontier of plant–soil feedback research: unraveling context dependence across biotic and abiotic gradients

• Published in: Journal of vegetation science Vol. 28; no. 3; pp. 484 - 494
• Main Authors: Smith-Ramesh, Lauren M., Reynolds, Heather L.
• Format: Journal Article
• Language: English
• Published: Hoboken John Wiley & Sons Ltd 01.05.2017; Wiley Subscription Services, Inc
• Subjects: Abiotic factors; Biotic factors; case studies; Community structure; Context dependence; Environmental factors; Feedback; Fertility; Global change; herbivores; Herbivory; Light; Literature reviews; Moisture; Natural enemies; Nutrients; Pathogens; Plant communities; Plant–soil feedback; soil; soil biota; Soil fertility; Soil moisture; soil-plant interactions; Soils; SYNTHESIS
• DOI: 10.1111/jvs.12519
• ISSN: 1100-9233

Question: Plant–soil feedback (PSF) has emerged as a ubiquitous phenomenon and a potentially important predictor of plant community structure and dynamics. However, the predictive power of PSF in field contexts is mixed, and ecologists do not yet understand its relative importance compared to other factors that structure communities. Further progress requires a more nuanced understanding of how PSF interacts with other biotic and abiotic factors. Environmental factors (e.g. natural enemies, moisture, light, nutrients) are known to affect plant interactions with soil and soil organisms, leading to an expectation of environmental context dependence in plant–soil feedback. Such context dependence could explain when PSF is expected to be an important driver of community dynamics, and under what conditions PSF is likely to be positive (destabilizing) vs negative (stabilizing). Methods: We conducted a literature review of studies that examined PSF across biotic and abiotic gradients. Results: Although few relevant studies have been conducted in this emerging research area, results to date suggest that plant–soil feedback is sensitive to biotic factors, such as above- and below-ground herbivory, and abiotic factors, such as nutrients and light. Conclusions: We develop a conceptual framework to predict variation in the direction and strength of PSF depending on the biotic or abiotic drivers of feedback (e.g. pathogens, nutrients) and the environmental context (e.g. intensity of herbivory, soil fertility). We explore the utility of our predictive framework through discussion of case studies from the literature on context dependence in PSF. We also consider how different experimental approaches might yield different insights about PSF–environment interactions, and suggest key future research directions.