Phosphorus Distribution in Channel-Bed Sediments in Beaver Creek, Knox County, Tennessee

• Main Author: Danovi, Angela Nicole
• Format: Text
• Language: unknown
• Published: TRACE: Tennessee Research and Creative Exchange 2011
• Subjects: Water Quality; Environmental Indicators and Impact Assessment; Environmental Monitoring; Environmental Sciences; Water Resource Management; Beaver Creek
• Online Access: https://trace.tennessee.edu/utk_gradthes/869; https://trace.tennessee.edu/cgi/viewcontent.cgi?article=1946&context=utk_gradthes

Beaver Creek, located in North Knox County, Tennessee, is on the Tennessee 303(d) list as an impaired stream that fails to meet its designated uses. Phosphorus (P) is one of the major pollutants of the stream. High P levels within surface water can lead to water quality problems including low dissolved oxygen, overgrowth of algae, and eutrophication. Two sources, pasture grazing areas and major municipal point sources, have been identified as important contributors of P to Beaver Creek. The objective of this study was to analyze the total P and Mehlich III extractable P concentrations of sediments in Beaver Creek and determine if a P signal could be identified in sediments collected along two stream reaches, less than 1500 m long, adjacent to a cattle farm and a wastewater treatment plant (WWTP). Eight sites were sampled within Beaver Creek, divided between two locations. At each sample location, four sample sites were selected. One site, the “control” was upstream of the P input. One, the “source,” was immediately downstream of the P input. Two additional sites, one within 200 m and the second within 400 m downstream of the source, were selected at each location. Nine sediment samples were collected at each sample site. Sediments were analyzed for total P (SW-3050B) and Mehlich III extractable P. ANOVA was run between the sites at each location and t-tests were completed to look for significant differences and a downstream signal. At the cattle farm, P concentrations of sediments at the downstream 2 site were significantly higher than sediment P concentrations at the three other sites. However, unexpectedly high results from the control sample site, combined with unexpectedly low results from the source sample site made it difficult to assess whether the cattle farm was affecting sediment P in Beaver Creek. At the WWTP, the sediment P near the outfall was significantly higher than sediment P at the control. Sediments at the downstream 1 site had significantly higher P concentrations than sediments at the other three sites, indicating that the WWTP may be affecting sediment P in Beaver Creek. This study supports the hypothesis that increased P concentrations could be attributable to P inputs from a WWTP. However, further study is needed about the effects that pastures have on sediment P concentrations within Beaver Creek.