Date of Award:


Document Type:


Degree Name:

Doctor of Philosophy (PhD)


Wildland Resources

Department name when degree awarded

Rangeland Resources

Committee Chair(s)

Neil E. West


Neil E. West


Jim Dobrowolski


Layne Coppock


Doug Ramsey


Ben Norton


Allen Rasmussen


This work was a case study of historical ecological change in Tintic Valley, Juab County, Utah, an area historically impacted by mining and ranching activities common to much of the American West. The temporal framework for the study was approximately 120 years, the period of direct Euroamerican influence. In recognition of the ecological implications of cultural change, however, the impacts of prehistoric and protohistoric human activity on study area landscape patterns and processes were also explicitly addressed.

The study included a narrative description of historic land uses and ecological change in Tintic Valley, and examined the changes in landscape patterns and processes so revealed within the context of the state and transition model of rangeland dynamics. The case of Tintic Valley thus served as a test of the heuristic utility of the theory of self-organization in ecological systems, within which the state and transition model is embedded. This theoretical framework in turn was used to gain insight into the present state of the Tintic landscape, how that state has changed over time, and the nature of those forces leading to transitions between system states in the historic period.

The study employed archival research, personal interviews, repeat photography, field surveys, aerial photographs, and a geographic information system (GIS) to identify, describe, and quantify historic-era change in Tintic Valley landscape level patterns and processes. The analysis revealed dramatic change in both the landscape vegetation mosaic and the channel network of the study area over time. Evidence was found for direct anthropogenic influence in precipitating those changes, primarily through tree harvesting associated with mining and ranching activities and through the effects of historic roads and railroads on the Tintic Valley gully network. Results supported the working hypothesis of a change in system state in the Tintic Valley landscape in the historic period.

Taken together, historical narrative and theoretical context permitted a degree of prediction with respect to potential future conditions for the study area under different management scenarios. Future research directions and implications of the research results for ecosystem management are also discussed.