Nancy Collins JohnsonNancy Collins Johnson has been a professor of soil ecology at Northern Arizona University since 1997. She earned a PhD in Ecology and Plant Pathology from the University of Minnesota (with David Tilman) and a MS degree in Botany from the University o Wisconsin. Johnson and her students study interactions among communities of plants and soil organisms in natural and human managed ecosystems throughout the world. They have discovered that mycorrhizas and soil communities are sensitive to global change factors and they are seeking first principles to understand these responses. These studies are important because mycorrhizal symbioses influence plant community composition, soil stability, and belowground carbon storage. Read More Read Less