Bioassessment metrics and deposited sediments in tributaries of the Chattooga river watershed

Abstract

Excessive sedimentation places waters of the Chattooga River network at risk of biological impairment. Monitoring efforts could be improved by including metrics that are responsive to changes in levels of fine sediments. We sampled three habitats (riffle, depositional, bedrock outcrop) for benthic macroinvertebrates at four sites in three low-order, tributary reaches of the Chattooga River in winter and spring, 2001. We determined levels of deposited fine sediments in each sampled reach by visually estimating % surface cover. Benthic macroinvertebrate data were used to calculate five commonly used bioassessment metrics (density, richness, % EPT, NCBI, and EPT richness), which were used to assess Chattooga River waters (USEPA 1999). Of the five metrics, only % EPT was found to be significantly negatively correlated with deposited sediments.

Citation

Chiao, Erica; Wallace, J. Bruce. 2003. Bioassessment metrics and deposited sediments in tributaries of the Chattooga river watershed. In: Proceedings of the 2003 Georgia Water Resources Conference: 1-4