Kai Z. and Olivia L. will evaluate the impact of invasive annual grass and biological soil crust cover on soil moisture and are interested in whether or not biological soil crusts increase site resistance to invasive annual grasses in Susanville, CA. We also hope to develop a remote-sensing model which will predict the cover of invasive annual grasses for management purposes.

Biological soil crusts (BSC) are integral to dryland ecosystems and perform a variety of functions including nutrient cycling, erosion prevention, and improvement to site resilience and resistance in the event of disturbance. Climate change is reducing summer precipitation within the sagebrush steppe, which increases the susceptibility of these rangeland ecosystems to invasion by non-native annual grasses such as cheatgrass (Bromus tectorum). Invasive annual grasses are known to negatively affect forage value, soil quality, animal health, and site resistance to disturbances, such as fire. BSCs are specially adapted for semiarid landscapes and occupy bare mineral soil which would otherwise be susceptible to encroachment.

The outcome of our study includes a model utilizing high-resolution satellite imagery to explore how vegetation cover correlates with BSC cover and soil moisture, and ground truthing was implemented in order to corroborate results. Although analyses are ongoing, we expect that increased BSC cover may reduce the presence of annual invasive grasses and promote soil moisture. These results may assist in identifying high priority sites for invasive vegetation control, herbicide application, and aid in the development of best management practices in sagebrush steppe ecosystems.