Date of Graduation

Summer 2019

Degree

Master of Science in Geospatial Sciences

Department

Geography, Geology, and Planning

Committee Chair

Robert Pavlowsky

Keywords

hydraulic geometry, prescribed fire, headwater streams, forest management, Ozarks, geomorphology

Subject Categories

Geomorphology | Hydrology | Natural Resources Management and Policy

Abstract

Prescribed burning has been used over the past two decades to manage forests and restore shortleaf pine-oak woodlands in Mark Twain National Forest (MTNF). While soil studies have been completed, no assessments of burning practices on small drainage channel systems have yet been done. Headwater streams may account for more than two-thirds of total stream length and are important to the maintenance of hydrologic connectivity in watersheds. This study’s focus is on understanding the relationship between frequency of forest burning and channel morphology (size, shape, and substrate) of headwater streams (km2). A combination of field measurements, geo-processing methods, hydraulic modeling, and statistical analysis will be used to analyze channel form, substrate properties, and tree/down wood composition in headwater stream channels.Thirty eight channel sites were assessed with drainage areas ranging from 0.003 - 0.2 km2; reach slopes from 2 - 34%; bank-full channel widths from 0.4 - 10 m; average depths from 0.02 - 0.29 m; and areas from 0.01 – 2.2 m2. Valley width and drainage area were found to be the best overall predictors of channel form (r2= >0.70). Stepwise regression models improved single parameter morphology equations (r2= >0.85). Channel slope and elevation are important variables describing sediment size (r2=0.35-0.63). In-channel LWD and tree basal area equations were also developed (r2= 0.41-0.54). Importantly, land use factors such as roads, timber harvest, and prescribed burning had little effect on channel morphology. In Big Barren Creek watershed, headwater channel systems were located within colluvial-alluvial transition zones, included both single- and multiple-threaded forms, and were quantified by traditional hydraulic geometry analysis.

Copyright

© Grace F. Roman

Open Access

Share

COinS