Master of Arts / Department of Geography / Melinda Daniels / Large woody debris, (LWD), defined as pieces measuring ≥ 1 meter in length and ≥ 10
centimeters in diameter (Swanson and Lienkaemper, 1978; Marston, 1982) is an influential
stream component. Once stable LWD obstructs streamflow and regulates key processes, causing
increases in storage capacity, scouring, and variations to the bed, the extent contingent upon
LWD’s average length of residence time within a system. Several North American studies have
acknowledged the effects of interactions between wood, sediment, and flow regimes (Bilby,
1981; Keller, E.A., and Swanson, F.J., 1979; Montgomery et al., 1995; Wohl, E., 2008), linking
the triad to geomorphic changes, the redistribution of bed materials, and ecological benefits. A
consensual baseline reference for LWD’s function over time does not exist however, partly due
to previous research being primarily conducted in the Northeast and Pacific Northwest regions
where historic actions of humans, particularly riparian logging and stream clearing, have greatly
impacted the condition of the watersheds. Researchers having long-overlooked the Great Plains
and other regions not commonly associated with woody vegetation has increased the ambiguity
regarding the transferability of LWD findings between regions. By shifting the focus to a non-forested
region, the goal of this thesis is to measure the dynamics and influence of a prairie
stream’s wood load on sediment storage and bed morphology. The Kings Creek network study
area is located on the Konza Prairie Biological Station in northeastern Kansas, and drains one of
few remaining unaltered North American watersheds. Results document the ongoing forest
expansion into the surrounding pristine grassland, and provide a temporal context of the regions
changing climate representative of atypical stream conditions caused by drought. In total, 406
individual pieces of wood were measured. The wood load was lower than most forest streams
referenced (13.05 m[superscript]³/100 m), though higher than expected resulting from the absence of
streamflow. LWD stored 108 m[superscript]³ of sediment within the channel, and the cumulative volume of
LWD-formed pools was 169 m[superscript]³. Additionally, statistical analysis showed longitudinal bed
variations to be strongly associated to LWD abundance, further indicating that LWD influences
prairie stream processes similarly to those in a forest stream.
| Identifer | oai:union.ndltd.org:KSU/oai:krex.k-state.edu:2097/18207 |
| Date | January 1900 |
| Creators | Roberts, Brianna |
| Publisher | Kansas State University |
| Source Sets | K-State Research Exchange |
| Language | en_US |
| Detected Language | English |
| Type | Thesis |
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