Date of Graduation

Summer 2005

Degree

Master of Science in Geospatial Sciences

Department

Geography, Geology and Planning

Committee Chair

Robert Pavlowsky

Keywords

step-pool, geomorphology, siver, Mountain, stream, Buffalo River

Subject Categories

Geomorphology | Hydrology

Abstract

Step-pool and cascade morphology reflect the geological and climatic factors affecting channels in mountain watersheds. This study uses longitudinal and cross-section surveys of a headwater stream in the Boston Mountains of the Ozarks Plateau region in northwest Arkansas to describe channel form and develop quantitative models for comparisons with other regions. The Bowers Hollow Creek watershed (3.5 km2) is located within the boundaries of the Forest Service’s Upper Buffalo Wilderness Area. Step-pool morphology varies with the influence of lithology and sediment supply in the Boston Mountains. However, step height and wavelength relationships are generally similar to other regions. Distribution of step-pool forms occurred throughout the watershed. The study area exhibited on average reach slopes of 0.105 m/m, widths of 6.10 m, crest particle sizes of 440 mm, step height of 0.87 m, and step wavelength of 6.62 m. The mean step steepness for the watershed was 0.13, while the mean reach step length to height ratio was 9:1. Step height and steepness values can vary by > 30% according to measurement method. Thus, comparisons of step height-based relationships among different studies may be problematic unless a standardized method is selected to define step height.

Copyright

© Aaron M. Nickolotsky

Open Access

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