Forest Sciences Commons^™

Spatiotemporal Modeling Of Threats To Big Sagebrush Ecological Sites In Northern Utah, Alexander J. Hernandez

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study tested the performance of classification, regression, and ordination techniques to evaluate the spatiotemporal dynamics of threats to big sagebrush ecological sites. The research was focused on invasion by annual exotic grasses and encroachment by woodlands.

We sought to identify those areas that have had a persistent coverage of cheatgrass (Bromus tectorum) in big sagebrush ecological sites. We took advantage of the contrast in greenness between multi-temporal (within one year) remotely sensed vegetation indices captured in the spring and summer to find a distinct phenological signature that allowed mapping cheatgrass. We utilized support vector machines (SVM) to classify three …

Object-Based Segmentation And Classification Of One Meter Imagery For Use In Forest Management Plans, W. Kevin Wells

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This research developed an ArcGIS Python model that extracts polygons from aerial imagery and assigns each polygon a vegetation type based on a modified set of landcover classes from the Southwest Regional Gap Analysis Project. The model showed an ability to generate polygons that accurately represent vegetation community boundaries across a large landscape. The model is for use by the Utah Division of Forestry, Fire, and State Lands to assist in the preparation of forest management plans. The model was judged useful because it was easy to use, it met a designated 50% threshold of useable polygons, and it met …

Remote Sensing Of Sagebrush Community Structural Patterns Across Scales, Lisa A. Langs

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Throughout the Intermountain West there has been a substantial reduction in both the quantity and quality of sagebrush ecosystems. To assist current range management objectives, numerous efforts have been made to classify and map sagebrush communities using remotely sensed data. However, the amount of detail provided by these broad-scale mapping projects is often limited. This research evaluated the ability of a suite of airborne and satellite imagery to detect sagebrush community structural attributes, specifically percent canopy cover, live cover, density, size-vigor, and spatial arrangement of shrubs. Field data was collected at Camp Williams National Guard Training Facility near Bluffdale, Utah, …