The impact of reconstructed soils following oil sands exploitation on aspen and its associated belowground microbiome
Citation
Stefani, F., Isabel, N., Morency, M.J., Lamothe, M., Nadeau, S., Lachance, D., Li, E.H.Y., Greer, C., Yergeau, É., Pinno, B.D., Séguin, A. (2018). The impact of reconstructed soils following oil sands exploitation on aspen and its associated belowground microbiome. Scientific Reports, [online] 8(1), http://dx.doi.org/10.1038/s41598-018-20783-6
Plain language summary
The purpose of this study is to assess the impact on the soil microbiome of different remediation methods for sites used to extract oil from oil sands.
Two remediation methods were used: forest floor-mineral mix (FFMM) and peat-mineral mix (PMM). The bacterial and fungal communities of the PMM sites were significantly different from those of the sites remediated with FFMM. Specifically, diversity was lower in PMM compared to FFMM and to sites naturally disturbed by forest fires. Symbiotic taxa were also less represented.
Abstract
The objective of this study was to investigate the impact of different soil covers used to reclaim decommissioned oil sands mining sites on the genetic diversity of aspen and their associated belowground microbiota. Aspen genotyping showed that trees mostly originated from sexual reproduction on sites reclaimed with soil covers made of upland forest floor-mineral mix (FFMM) and lowland peat-mineral mix (PMM). In contrast, most individuals in mature and burned stands sampled as benchmarks for natural disturbances originated from vegetative reproduction. Nonetheless, aspen populations in the FFMM and PMM sites were not genetically different from those in mature and burned stands. DNA metabarcoding of bacteria and fungi in root and soil samples revealed that the diversity of the belowground microbiota associated with aspen and the relative abundance of putative symbiotic taxa in PMM were significantly lower than for FFMM and naturally disturbed sites. Despite similar aspen genetic diversity between FFMM and PMM sites, trees were not associated with the same belowground microbiota. Because the soil microbiome and more specifically the mycorrhizal communities are variable both in space and time, long-term monitoring is particularly important to better understand the ecological trajectory of these novel ecosystems.