Restoring California's Native Coastal Scrublands on a Revitalized Golf Course

Understanding limitations to the growth and distribution of Artemisia californica

Marian S. Walker, Germán Silva, Dr. Jennifer Y. King

University of California Santa Barbara Geography Dept.

Explored the geophysical implications of ecosystem restoration under the guidance of Dr. Jennifer King and doctoral candidate, Germán Silva from the UCSB's Geography Department. The objective of my study is to assess the feasibility of reestablishing coastal sage communities at North Campus Open Space. In gathering data for this project, I led a team of 10+ undergraduate students in conducting fieldwork and laboratory analyses. We collected vegetation data along transects, sampled soils, and analyzed soil bulk density measurements. Additionally, I utilized Trimble GPS navigation for sample site determination and mapping in ArcGIS Pro.

Research Poster

Abstract

Restoration projects aim to reestablish native plant communities and support the growth of biodiverse ecosystems although, the variability of the natural environment presents challenges to those goals. At the University of California Santa Barbara’s North Campus Open Space (NCOS), the success of coastal sage scrub restoration relies on the strong establishment of keystone species, including California sagebrush (Artemisia californica). This study investigates the correlation between California sagebrush growth (plant size) and soil bulk density. We hypothesized that areas of NCOS with lower soil bulk density are more favorable for supporting California sagebrush communities than those with higher soil bulk density. This relationship was explored by gathering soil samples and measuring longest branch lengths across two distinct zones. Results from statistical analyses indicate a weak correlation between soil bulk density and longest branch length across both zones (R = 0.161, r2= -0.413) which provides a potential explanation for approximately 41.3% of the decrease in plant size as soil bulk density increases. While bulk density does not fully explain the differences in California sagebrush growth, our results indicate that it may be an important contributing factor to differential growth in restoration sites. Understanding this relationship may help land managers improve the success of California sagebrush establishment at NCOS and similar restoration.