Master of Science degree with a major in Natural Resources: option Environmental Science and Management
Committee Chair Name
Dr. David Gwenzi
Committee Chair Affiliation
HSU Faculty or Staff
Second Committee Member Name
Dr. Buddhika Madurapperuma
Second Committee Member Affiliation
HSU Faculty or Staff
Third Committee Member Name
Dr. Yu Wei
Third Committee Member Affiliation
Community Member or Outside Professional
Environmental Science and Management
The prevalence of black bear (Ursus americanus) bark stripping in commercial redwood (Sequoia sempervirens) timer stands has been increasing in recent years. This stripping is a threat to commercial timber production because of the deleterious effects on redwood tree fitness. This study sought to unveil a remote sensing method to detect these damaged trees early and map their spatial patterns. By developing a timely monitoring method, forest timber companies can manipulate their timber harvesting routines to adapt to the consequences of the problem. We explored the utility of high spatial resolution UAV-collected hyperspectral imagery as a means for early detection of individual trees stripped by black bears. A hyperspectral sensor was used to capture ultra-high spatial and spectral information pertaining to redwood trees with no damage, those that have been recently attacked by bears, and those with old bear damage. This spectral information was assessed using the Jeffries-Matusita (JM) distance to determine regions along the electromagnetic spectrum that are useful for discerning these three-health classes. While we were able to distinguish healthy trees from trees with old damage, we were unable to distinguish healthy trees from recently damaged trees due to the inherent characteristics of redwood tree growth and the subtle spectral changes within individual tree crowns for the time period assessed. The results, however, showed that with further assessment, a time window may be identified that informs damage before trees completely lose value.
Magstadt, Shayne R., "Can a remote sensing approach with hyperspectral data provide early detection and mapping of spatial patterns of black bear bark stripping in coast redwoods?" (2021). Cal Poly Humboldt theses and projects. 490.