Presenter: Julia Odenthal – Environmental Studies
Faculty Mentor(s): Lucas Silva
Session: (In-Person) Poster Presentation
Forest soils present a crucial opportunity for carbon sequestration to combat rising atmospheric greenhouse gas concentrations. To better understand the impact of tree planting on soil carbon storage within a previously unforested grass field in Oregon’s Willamette Valley, we will measure soil microbial respiration at the base of two conifer seedlings with different mycorrhizal associations: Calocedrus decurrens (arbuscular mycorrhizae; AM) and Pinus ponderosa (ectomycorrhizae; EcM). We will compare these measurements with soil respiration in plowed furrow replicates at a five foot distance from the sample trees and in unplowed pasture. We hypothesize that soil respiration will be higher next to seedlings compared to pasture and disturbed ground, and that AM seedlings will have higher soil respiration rates than EcM seedlings. In addition, we will measure pH, soil carbon, macronutrient, and micronutrient levels at the same locations to compare soil conditions that may alter microbial communities. Microbial function at the roots of planted trees has been shown to have some control on carbon sequestration through enhanced weathering, suggesting that current models may underestimate the carbon storage potential of forested soils. Understanding the potential of carbon sinks is key to properly allocating resources for climate change mitigation. Our data will guide future local tree planting efforts to maximize soil carbon storage.