Soil and root microbiome in sites under reclamation in Fort McMurray

Different soil covers were used to reclaim decommissioned oil sands mining sites, leading to the emergence of new ecosystems. The objective of this study was to investigate the soil microbiome of these new environments naturally recolonized with aspen trees. DNA metabarcoding of bacteria and fungi in aspens root and soil samples revealed that the diversity of the belowground microbiota associated with aspen and the relative abundance of putative symbiotic taxa in lowland peat-mineral mix (PMM) were significantly lower than for upland forest floor-mineral mix (FFMM) and mature and burned stands sampled near the reclamation sites to act as benchmarks for natural disturbances. Despite the genetic diversity and origin of trembling aspen being similar between FFMM and PMM, trees were not associated with the same belowground microbiota, and long-term monitoring is suggested to better understand these new ecosystems.