Assessment of Watershed Health on Intermittent Watersheds in Southwestern North Dakota

Abstract

Watersheds are complex systems that are influenced by many factors including geomorphology, climate, soil, vegetation, and land management. Due to this complexity, a watershed assessment that evaluates both the riparian and upland areas has yet to be developed. We proposed investigating a combination of plant community composition within the greenline, upland ecological site function assessment with the Interpreting Indicators of Rangeland Health (IIRH) protocol, and stream morphological parameters. Stream parameters investigated were Rosgen’s classification method, bank erosion hazard index (BEHI) and bank height ratio (BHR). This research was conducted on five intermittent streams in southwestern North Dakota. We found that facultative wetland species offered the most protection to intermittent streambanks as a result of hydrology. When assessing the uplands it was determined that there is a positive correlation between rangeland health and riparian health. The stream parameter that showed the strongest relationship was the BEHI.