With climate change plants have been able to shift their ranges into novel environments were conditions have been made suitable due to warming temperature and changes in precipitation. When a plant moves into a novel system the interactions with the belowground microbial communities can influence establishment, productivity and even ecosystem function. Much research has focused on either positive plant-soil interactions, such as AMF symbiosis, or on negative plant-soil interactions, such as pathogens. Less focus has been given to the commensal microbial community, of which the majority of soil microbes are a part of. A better understanding of how the commensal microbial community changes across a plants’ range, and in the new range, can provide insight into plant range shifts and inform on the role of the core microbial community under different plant species.
To determine how soil and root microbial communities change under range shifting plant species we collected soil and root samples from native and range expanding plant species spanning a north-south latitudinal transect in central Europe (from the Netherlands to Greece). Using high-throughput Illumina sequencing we assessed bacterial, archaeal and fungal communities (using 16S and ITS primers). We compared how the soil and root microbial communities - community composition, diversity and interactions - differed within and between plant species across the north-south gradient.
Results/Conclusions
In both soil and root samples, plant species identity, geography, and the soil environment were determinants of microbial community composition. However, while community patterns in bulk soils under range shifting plant species were quite weak, we observed stronger trends in root communities indicating that it is at the root-soil interface where most important interactions are likely to occur. In addition to assessing microbial community composition and diversity, we examined a number of taxa that consistently occurred in the soils and roots of range expanding plant species. Together our work demonstrates that range shifts can interrupt plant-soil interactions, and that both range (geography) and plant species can influence re-organization of belowground communities.