Restoration on magnetite mine waste substrates using Western Australian native plants only marginally benefited from a commercial inoculant

Post-mining landscapes often lack self-sustaining plant communities and functional belowground microbial communities. Inappropriate management of soil can hinder ecological restoration of mine sites. However, the potential role of microbial inoculants and plant nutrient-acquisition strategies in improving mined substrates and facilitating mine-site restoration remains relatively unexplored. An eight-month glasshouse experiment was conducted to test: (1) whether a commercially-available microbial inoculant was effective in restoring biological properties of mined substrates, and (2) the effect of plant nutrient-acquisition strategies on improving the chemical properties of mined substrates for the growth of native plants. There was no significant improvement in plant growth by adding a commercially-sourced microbial inoculant. Soil microbial biomass carbon and phos-phorus increased significantly after plant growth (main effect of species * substrates * inoculation interaction). The non-mycorrhizal disturbance-specialist plant species Maireana georgei was effective in improving hostile conditions of the mine waste. Our results highlight that re-vegetating stockpiled topsoil using local keystone species is a desirable practice that can improve soil biological properties and benefit mine-site restoration. Commercially-available agricultural-based microbial inoculants may not be compatible for mine-site restoration using native plants, but future research using indigenous soil microbes is warranted.

Automated summary

Post-mining landscapes often lack self-sustaining plant communities and functional belowground microbial communities. Inappropriate management of soil can hinder ecological restoration of mine sites. The potential role of microbial inoculants and plant nutrient-acquisition strategies in improving mined substrates and facilitating mine-site restoration remains relatively unexplored.