Predicting the structure of soil communities from plant community taxonomy, phylogeny, and traits

Abstract

There are numerous ways in which plants can influence the composition of soil communities. However, it remains unclear whether information on plant community attributes, including taxonomic, phylogenetic, or trait-based composition, can be used to predict the structure of soil communities. We tested, in both monocultures and field-grown mixed temperate grassland communities, whether plant attributes predict soil communities including taxonomic groups from across the tree of life (fungi, bacteria, protists, and metazoa). The composition of all soil community groups was affected by plant species identity, both in monocultures and in mixed communities. Moreover, plant community composition predicted additional variation in soil community composition beyond what could be predicted from soil abiotic characteristics. In addition, analysis of the field aboveground plant community composition and the composition of plant roots suggests that plant community attributes are better predictors of soil communities than root distributions. However, neither plant phylogeny nor plant traits were strong predictors of soil communities in either experiment. Our results demonstrate that grassland plant species form specific associations with soil community members and that information on plant species distributions can improve predictions of soil community composition. These results indicate that specific associations between plant species and complex soil communities are key determinants of biodiversity patterns in grassland soils.

Linking ecology and plant pathology to unravel the importance of soil-borne fungal pathogens in species-rich grasslands

“…Whereas the fungal communities were distinctly different between two grasses and two legumes grown in monoculture, they became similar when the species where grown in mixtures. Furthermore, plant species identity in 4-species grassland mixtures was associated with bacterial and fungal community composition in the soil (Leff et al 2018).…”

Range-expanding plant species and their belowground neighbours : digging into novel interactions

“…In grassland communities, aboveground pathogen pressure is determined by the phylogenetic structure of the plant community (Parker et al 2015). Whether belowground pathogen pressure is explained in a similar way has not yet been studied (but see Leff et al 2018). However, in case of such a phylogenetically structured belowground pathogen community, related plant species will experience similar pathogen pressures and therefore will likely show similar defence mechanisms.…”

“…While plant-soil feedback differences among taxonomically diverse plant species might be explained by phylogeny (Anacker et al 2014), very few -if any-studies have tested whether closely related congeneric species, such as sister species, have a more similar pattern of plant-soil feedback than distantly related congeneric species. Likewise, only few studies have studied the whole rhizosphere microbiome including nematodes among plant species (Leff et al 2018), while differences of only distinct parts of the microbiome were compared between congeneric plant species (Bouffaud et al 2014;Schlaeppi et al 2014). …”

A plant’s inheritance : Soil legacy effects of crops and wild relatives in relation to plant functional traits

“…However, it remains to be tested how results obtained in individual plants grown in controlled conditions translate into effects in plant communities, as results on plant community level are contradictory. In both tropical forests (Barberán et al 2015) and temperate grasslands (Leff et al 2018) soil microbial community composition could be related to plant community composition, but not to plant traits. Which raises the questions:…”

“…Plant functional traits, such as SRL, root N concentration and aboveground biomass explained microbial community composition in various studies (Legay et al 2014;Legay et al 2016;PerezJaramillo et al 2017;Fitzpatrick et al 2018), but not in Leff et al (2017) and Leff et al (2018).…”