Evaluating soil-plant-microbe interactions as a technology for forest ecosystem restoration

点击翻译按钮获取中文摘要

Most old-growth forests in Canada have been destroyed and restoration efforts have produced systems that look and function very differently than the original. This is because the mechanisms that regulate the developmental stages of a forest are poorly understood. There is increasing evidence that the large diversity of organisms living in soils not only play roles in nutrient cycling but also interact very closely with plants. Many of these interactions determine the diversity and productivity of plants and some have attracted the interest of biotechnology companies, which have been using them in forest restoration efforts. In Northern Canada, many hectares affected by mining practices have been planted with alders, a tree that forms symbioses simultaneously with mycorrhizal fungi and nitrogen fixing microbes. Our project aims to assess the impact of restoration efforts using alders colonized with different mycorrhizal inocula on the establishment and survival of plants typical of undisturbed forest systems. The effects of our interventions on ecosystem functioning, including potential greenhouse gas (GHG) emissions, contaminant remediation, carbon sequestration and soil microbial and plant community biodiversity will also be considered. We will link the biological and physicochemical components using molecular and micrometeorological techniques in our measurements. The former are ideal to characterize microbial diversity and function and the latter to characterize the temporal dynamics of GHG emissions. Additionally, we will measure nutrient transfer between plants through mycorrhizal networks and different pools of carbon, including glomalin, a compound produced by some mycorrhizal fungi that is important in soil structure and long-term C sequestration. We expect that our results will lead to increased understanding of the role of soil-plant-microbe interactions in restoration ecology and their potential to mitigate climate change.