How Interactions Belowground Make the Aboveground Possible
Start Time & Date
Archived video recording of this presentation.
Unseen and largely unidentified, soil biota are constantly at work below our feet, storing and releasing carbon, cycling nutrients, and creating structure in the soil. Their contributions to ecosystem stability have long been appreciated (by some!), but we are only beginning to unravel the associated mechanisms. As an example of this, we will take a close look at one important group of soil biota, arbuscular mycorrhizal fungi, which form symbioses with 80% of terrestrial plant species. These fungi grow into plant roots, where they exchange nutrients for plant carbohydrates. They simultaneously extend out from plant roots, where they mine for nutrients and interact with soil biota. Early mycorrhizal researchers proposed the ‘direct mineral cycling’ hypothesis, suggesting that these fungi move nutrients directly from leaf litter to their host plants, thereby retaining nutrient capital and enabling plant success in infertile soils. We will talk about why this hypothesis fell out of favor for decades, curious findings from our own Bellingham forests, and recently revealed mechanisms which have us revisiting the ‘direct mineral cycling’ hypothesis, and the role of these fungi in ecosystems, once again.
Rebecca Bunn is an Associate Professor in the Department of Environmental Sciences at Western Washington University. She studies plant-soil interactions with a particular focus on how mycorrhizal fungi alter plant success under different conditions. In addition to observational and experimental studies, she also works on data synthesis projects which leverage previously published data to broadly understand the impacts of mycorrhizae on plants and plant communities. She grew up in Northern Michigan hunting morel mushrooms and working in a plant nursery and she is grateful to have many opportunities at work to keep her hands dirty.
Location & Time
Presentations are held each Thursday at 4:30pm ONLINE.