Lichens Reduce Heat and Water Stress for Jack Pines Growing on Mine Tailings
Iron mining is an important industry in northern Minnesota but has caused the disturbance of boreal ecosystems. Lichens grow abundantly on abandoned tailings mounds made of mine waste but the successional processes of these technogenic landscapes are not fully understood. Through experiments in the field, and in the greenhouse, we investigated how lichens facilitate the revegetation of Pinus banksiana, (jack pine) on mine tailings by reducing water and heat stress in this harsh environment. Lichens significantly increased the water content of the mine tailings, and kept soil temperature cooler than exposed tailings. This amelioration of the microclimate for vegetation is a critical role that lichens play in this ecosystem and its succession.