Presenter(s): Aaron Lefore − Environmental Science
Faculty Mentor(s): Lucas Silva, Schyler Reis
Poster 71
Research Area: Physical Science
The terrestrial carbon pool, especially soils, have the potential to sequester large amounts of carbon by way of below ground carbon flux. However, the degree of carbon sequestration into soils is dependent upon the structure of the vegetation communities inhabiting them and the unique qualities of the soil itself. This study focuses on below ground carbon concentrations, specifically soil organic carbon (SOC), in relation to vegetation communities in the Chewaucan River Basin in southern Oregon. Over time, management practices within the Chewaucan site have resulted in major vegetation shifts, defined by woody Juniper encroachment, cheatgrass invasion, and dryland agriculture practices. To calculate SOC, cores from the top 10cm of soil were taken from different vegetation community plots across the site that included Juniper, Ponderosa Pine, sagebrush, Juniper/Pine, and alfalfa. Samples were dried to determine bulk density, texture, and Munsell color system rating. Soil sieving separated samples into coarse earth (>2.00mm) and fine earth fractions (< 2.00mm). A loss on ignition (LOI) test was completed on 5.00g fine earth from each sample to determine SOC values. Simple calculations show woody species (Ponderosa, and Juniper) plots having slightly elevated SOC concentrations than shallow rooted species (sagebrush, alfalfa). However, more complex analytical procedures will be completed using R statistical computing that account for multiple variables across all plots. This study has the potential to quantify SOC concentrations of soils that have not previously been analyzed. More importantly, this research could predict changes in SOC within rapidly changing ecosystems like the Chewaucan River Basin.