Investigating Whether Big Basin Sagebrush (<em>Artemisia Tridentata</em>) Facilitates Native Forb Diversity

Biodiversity shapes ecosystems’ functions, including many that humans rely upon [1]. Some species can increase local biodiversity by creating niches that would be otherwise unavailable in their absence, facilitating the presence of other species [2]. In the western, U.S. big sagebrush (Artemisia tridentata) is a foundational shrub species in arid desert ecosystems. A survey of sagebrush steppe plant species at several experimental plots in Southwest Idaho found higher diversity of plant species beneath sagebrush canopies compared to adjacent areas without sagebrush plants (interspace areas) [3]. This indicates that sagebrush may facilitate plant species diversity, possibly by altering soil properties. To investigate whether sagebrush facilitates native plant diversity by altering local soil properties, I will conduct a manipulative greenhouse experiment. Seed mixes created utilizing eight native forb species will be planted in soil collected from underneath sagebrush plants and in soil from interspace areas at two different sites in Southwest Idaho. I predict that greater richness of the planted species will be observed when grown in sagebrush soils compared to interspace soils. This result would suggest that sagebrush facilitates plant diversity by conditioning soils, and prompt further questions about the mechanisms underlying this phenomenon. References Cardinale, B. J., Duffy, J. E., Gonzalez, A., Hooper, D. U., Perrings, C., Venail, P., Narwani, A., Mace, G. M., Tilman, D., Wardle, D. A., Kinzig, A. P., Daily, G. C., Loreau, M., Grace, J. B., Larigauderie, A., Srivastava, D. S., & Naeem, S. (2012). Biodiversity loss and its impact on humanity. Nature, 486(7401), 59–67. https://doi.org/10.1038/nature11148 McIntire, E. J. B., & Fajardo, A. (2014). Facilitation as a ubiquitous driver of biodiversity. New Phytologist, 201(2), 403–416. https://doi.org/10.1111/nph.12478 Fox, S., Addams, R., Levy, H., deGraff, M., Caughlin, T., Bittleston, L., Simler-Williamson, A. (2024). Interactions between plant community diversity and soil biotic and abiotic properties in sagebrush (Artemisia tridentata) steppe ecosystems. Idaho Conference on Undergraduate Research. Poster.