Date of Award
Master of Science (MS)
This thesis assessed the physical characteristics and stability of selected western Minnesota streams that cross the eastern beach ridges of glacial Lake Agassiz. Stream and river channels in this area host unusually diverse aquatic habitat and biodiversity, but incompatible land use along channels and in watersheds impair their quality and function. Previous rapid assessment protocols have been developed for stream attributes and stability, but these methods have been developed elsewhere in the United States and are not necessarily appropriate for western Minnesota’s unique geology and landscape.
A rapid reconnaissance method was developed to assess stream conditions using an integrated numerical scoring and qualitative ranking survey developed from field data collected during the project. Although ecological function and habitat quality are the main consideration, this project focused on the physical characteristics of a reach, without explicit consideration of water chemistry or indices of biological integrity.
The final stream assessment is referred to as SAMBR (Stream Assessment for Minnesota’s Beach Ridges) and is based on seven indicators that are used to rate stream segments as poor, fair, good, or very good. The indicators are: (1) instream habitat, (2) riparian buffer, (3) access to floodplain, (4) sinuosity, (5) degree of incision, (6) bank stability, and (7) incipient particle diameter and channel material. The method is generally applicable to wadeable streams throughout the Minnesota glacial Lake Agassiz beach ridges. This assessment is unique because it uses an analytic hierarchy process to weigh more heavily the indicators that are more important in achieving biodiversity, versus the indicators that are slightly less important. This method can be easily adapted to emphasize other stream assessment goals and objectives.
Franklund, Abigail V., "Developing a rapid method for assessing the physical stability of streams in Minnesota's Agassiz beach ridges" (2007). Theses and Dissertations. 98.