The impact of in-stream gravel mining on the particle size distribution of a gravel bed stream

摘要

The purpose of this study was to examine the potential impacts of gravel mining on streambed substrate characteristics on streams of Buck Creek watershed of the Cumberland River basin. Since particle size distribution affects bed roughness and sediment transport behavior as well as the type of aquatic habitat, a study of the particle size distribution of gravel bed streams was needed to quantify the potential impacts of gravel mining in this region.;Site surveys were conducted and bulk and surface gravel samples were collected from two tributaries of Buck Creek in the Cumberland River Basin. The first, Indian Creek, has an extensive history of gravel mining; the second, Clifty Creek, is geomorphologically very similar to Indian Creek yet has no known history of substantial gravel extraction. Particle size distributions were compared at different areas within each stream and the overall distributions for both streams were compared. Indian Creek showed the same distribution tendencies throughout the studied reach. Also, the overall particle size distributions were found to be similar between the streams. Although many of the stereotypical impacts of gravel mining were observed in Indian Creek, it was concluded that gravel mining on Indian Creek has not changed the particle size distribution of the stream substrate material. An ancillary finding of this research was the exposure of large regions of bedrock as channel substrate in regions upstream of persistent gravel mining and the channel incision into the bedrock. (Abstract shortened by UMI.).