Sustainable revegetation of iron mine tailings of North-Eastern Québec and Labrador: selection of plant species, creation of a living soil and root microbial symbioses

Abstract

The revegetation of iron mine tailings of northeastern Québec and Labrador faces several technical challenges, due to the poor fertility of the soil, the importance of wind erosion and the northern climate. The company Irrigation NORCO Inc. has been efficiently addressing these challenges for more than 18 years on several tailings sites. The technology used is based on the primary use of hay mulch to control wind erosion, an in-depth knowledge of the local flora adapted to the region, and the use of biological fertilizers which permit, in addition to providing organic amendments, to restore the soil microbial life. Soil analyses realized over the years testify to the creation of a fertile soil. Root mycorrhizal analyses demonstrate that symbiotic hyphal networks re-establish themselves very rapidly on vegetated sites, with nevertheless a great variability among plant species. It is to be hoped that the effectiveness of Irrigation NORCO technology will be allowed in the years to come to continue the revegetation of the hundreds of ha of virgin tailings remaining which are destined to remain artificial deserts without human intervention.