The soil microbial community predicts the importance of planttraits in plant–soil feedback

Link: http://onlinelibrary.wiley.com.proxy.lib.iastate.edu/doi/10.1111/nph.132...

Ke et al. New Phytologist (2015) 206: 329–341

Abstract

Reciprocal interaction between plant and soil (plant–soil feedback, PSF) can determine plantcommunity structure. Understanding which traits control interspecific variation of PSFstrength is crucial for plant ecology. Studies have highlighted either plant-mediated nutrientcycling (litter-mediated PSF) or plant–microbe interaction (microbial-mediated PSF) as impor-tant PSF mechanisms, each attributing PSF variation to different traits. However, this separa-tion neglects the complex indirect interactions between the two mechanisms.
We developed a model coupling litter- and microbial-mediated PSFs to identify the relativeimportance of traits in controlling PSF strength, and its dependency on the composition ofroot-associated microbes (i.e. pathogens and/or mycorrhizal fungi).
Results showed that although plant carbon: nitrogen (C : N) ratio and microbial nutrientacquisition traits were consistently important, the importance of litter decomposability varied.Litter decomposability was not a major PSF determinant when pathogens are present. However, its importance increased with the relative abundance of mycorrhizal fungi as nutrientreleased from the mycorrhizal-enhanced litter production to the nutrient-depleted soils resultin synergistic increase of soil nutrient and mycorrhizal abundance. Data compiled from empiri-cal studies also supported our predictions.
We propose that the importance of litter decomposability depends on the composition ofroot-associated microbes. Our results provide new perspectives in plant invasion and trait-based ecology