October 1, 2016.
Santa Rosa Island is one of the Channel Islands off the coast of southern California. Before the island was heavily grazed, Santa Rosa Island is thought to have had large stands of island oak trees, Quercus tomentella, that provided a critical source of water for the ecosystem by creating a “cloud forest”. Wind-borne fog collects on the leaves, branches, and twigs of the island oaks and other native shrubs. Once the water condenses it drips, falls, and soaks into the soil. Introducing cattle and especially sheep to the island has damaged the ecosystem and nearly decimated Santa Rosa Island of its native oaks and woodland plants. The Cloud Forest Restoration project aims to restore native trees and other plants to the central high ridge. Fog panels covered in mesh have been installed in areas on the ridge to collect fog and drip water down into the soil. In my study, soil moisture data was collected at areas 5 centimeters down slope from fog fences and above wattles (coconut fiber rolls used to prevent erosion of the slope). A second set of data was collected at areas with wattles only. Soil moisture readings were taken at 5 and 10 centimeters depths. The data suggests that the soil at fog fences is moister at both depths of 5 and 10 centimeters than at areas with wattles only. In addition, the soil was moister at 10 centimeters than 5 centimeters at sites with fog fences, suggesting substantial subsurface infiltration. This has implications for future planting projects because the extra fog drip provided by the panels does seem to be a significant source of moisture for new transplants.
Biology | Ecology and Evolutionary Biology | Life Sciences
California State University, Channel Islands (CSUCI)
*This project was supported by a grant to the California State University STEM Teacher Researcher (STAR) Program from the Howard Hughes Medical Institute.