August 5, 2012
One of our main projects for this internship is establishing native plant restoration sites within previously disturbed soil along the Deer Valley trail adjacent to USC’s Wrigley Institute for Environmental Studies. The first site is along a disturbed slope where fennel (Foeniculum vulgare) was removed manually last year and has begun to re-sprout. The second site was degraded due to soil collection for maintenance purposes; thus, both the area of removal and the connecting path traveled by trucks and bulldozers is where we plan on working. We hope these sites will provide data for native plants’ effects on the area through soil nutrients and overall growth, as well as what restoration methods have the highest rates of survivorship. Along an interpretive trail, the sites will provide educational opportunities for students, residents, and other visitors on restoration efforts.
We are working towards installing restoration plots that will provide data on what methods increase rates of survivorship. Periodically, we will test the soil for nitrogen and carbon content; thus, creating a baseline for how native plants contribute to nutrient pools in a disturbed area. We hope that the results from this project will possibly provide an alternative to carbon emission cap and trade. Instead of a market-based solution for businesses to offset their carbon emissions, we theorize that by investing in restoration efforts, businesses will contribute to the improvement of disturbed ecosystems while also promoting sustainability.
With the guidance of Peter Dixon, Senior Technician for the Catalina Island Conservancy Native Plant Nursery, we have formulized not only a restoration plan, but also an experimental design within it. Prior to any restorative work, we will test the soil to quantify its quality.We will compare various plant mixtures of seeded and potted plants, perennials and annuals. Fortunately, the location of the restoration site is within an area of relatively high native plant diversity. During a recent site survey, Dixon identified over 20 native plant species present, and we are working towards identifying several more native grasses. From these preexisting plants, we plan to collect seed, process it, and replant within the restoration site. Furthermore, we will be looking at the varying successes of planting annuals, climax species such as Lemonade Berry (Rhus integrifolia) and Toyon (Heteromeles arbutifolia), and coastal sage shrub species. In order to ensure the success of the site, we will use erosion mats to prevent soil erosion, and fencing to prevent deer and bison predation.
In terms of timing, seeding will occur in August, while all potted plants and shrubs will be planted just before fall to maximize the amount of rainfall available. In addition, our plant plots will be watered monthly during initial plant establishment. However, we will include control plots to observe the success of plants that are not manually watered. The four of us will continue to work on these restoration sites throughout the fall and early winter. The fall and spring ENST 320A classes may also take soil samples for the field component of the course. Next summer’s USC interns will continue expanding on the restoration sites and assume basic maintenance.
Editor’s note: The ENST Catalina Island Internship at USC Dornsife is offered as part of a summer internship program offered to undergraduate students in the USC Dana and David Dornsife College of Letters, Arts and Sciences. This course takes place on location at the USC Wrigley Marine Science Center on Catalina Island. Students investigate important environmental issues such as ecological restoration, protected-area planning and assessment, and invasive species management. During the course of the internship, students will work closely with USC faculty and staff scientists from the Catalina Island Conservancy to support ongoing conservation and management programs being implemented on the island. Instructors for the course include David Ginsburg, Assistant Professor of Environmental Studies, Lisa Collins, Lecturer in Environmental Studies, and Tony Summers, Invasive Plant Program Supervisor from the Catalina Island Conservancy.