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<br /> <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br />I <br /> <br /> <br />to be lower than those along braided rivers. Meandering rivers are characterized by finer <br />sediment (clay- to sand-sized), gentler downstream slopes, less variable flow, and stream <br />banks more resistant to erosion, relative to braided rivers. <br /> <br />Abstract of Jaquette's M.S. Thesis <br /> <br />Sediment and channel dynamics of a 45-km reach of the North Fork of the <br />Gunnison River in Colorado were evaluated to provide a context for channel <br />rehabilitation efforts. The North Fork of the Gunnison is a snowmelt-driven, mountain <br />river draining 2500 km2 of mostly forested, steep terrain. Climate is semi-arid in the <br />lower valley to alpine in the surrounding mountains. Geology in the watershed consists <br />mainly ofthree units: the highly erodible Tertiary Wasatch Formation, the underlying <br />Mesa Verde Formation, and the less resistant Cretaceous Mancos Shale unit below. Since <br />permanent Anglo settlement in the late 19th century, primary land uses have been coal <br />mining, agriculture, livestock grazing, gravel mining, and logging, most of which occur <br />in the lower valley. <br /> <br />The study reach extends 45 km downstream from the junction of Anthracite and <br />Muddy creeks to below the town of Hotchkiss. This reach was subdivided into the upper <br />(first 23 km) and lower valley based on a distinct change in planform from a single- <br />thread to a braided channel. One km on either side of the modern channel was field- <br />mapped to identify the spatial extent of land use types, sediments sinks, and potential <br />sediment sources. Pebble counts were performed on potential hillslope sources and valley <br />bottom sinks. Grain-size distribution results were used to analyze the relationship <br />between sediment sinks and potential sources, and the significance of potential local and <br />watershed scale controls. A planform stability analysis was performed using historical <br />aerial photographs with remote sensing and GIS software to reconstruct the recent history <br />of channel configuration along the studied reach. Field and historical data were used to <br />discuss the dominant factors that influence sediment and channel dynamics along the <br />North Fork of the Gunnison River. <br /> <br />2 <br />