Low levels organic amendments improve fertility and plant cover on non-acid generating gold mine tailings

We tested the use of low quantities of organic amendments (5.3 t ha−1 papermill sludge and 5.6 t ha−1 woodchips) and fertilizer in enhancing the cover and survival of vegetation on mine tailings. Plots were subdivided and seeded with a mix of grasses and/or alfalfa and planted with native Picea mariana. The papermill sludge amendment and grass seeding resulted in the highest plant cover and survival of plant P. seedlings. This amendment and the subsequent plant establishment lead to improvements in substrate aggregation and organic content. Other amendment treatments never exceeded 50% cover, and did not improve substrate physical characteristics. The initial pulse of chemical nutrients provided by amendments was relatively short-lived, with all amendment treatments returning to their background levels within one to two growing seasons. This study suggests that certain abandoned tailings dumps can be revegetated with minimal input.