Evaluating the rhizospheric and endophytic bacterial microbiome of pioneering pines in an aggregate mining ecosystem post-disturbance.

Aims: Despite little soil development and organic matter accumulation, lodgepole pine ( Methods: We characterized the diversity, taxonomic composition, and relative abundance of bacterial communities in rhizosphere and endosphere niches of pine trees regenerating at the gravel pit along with comparing them with a nearby undisturbed forested site using 16S rRNA high-throughput sequencing. Additionally, the soil and plant nutrient contents at both sites were also analyzed. Results: Although soil N-content at the gravel pit was drastically lower than the forest site, pine tissue N-levels at both sites were identical. Beta-diversity was affected by site and niche-type, signifying that the diversity of bacterial communities harboured by pine trees was different between both sites and among various plant-niches. Bacterial alpha-diversity was comparable at both sites but differed significantly between belowground and aboveground plant-niches. In terms of composition, pine trees predominantly associated with taxa that appear plant-beneficial including phylotypes of Conclusions: Our results suggest that, following mining activity, regenerating pine trees recruit bacterial communities that could be plant-beneficial and support pine growth in an otherwise severely N-limited disturbed environment. Supplementary Information: The online version contains supplementary material available at 10.1007/s11104-022-05327-2.