Document: SET-3-69-48

The impact and persistence of sediment pollution from construction sites on stream community structure.

REICE, S.R.*

University of North Carolina, Chapel Hill, NC 27599-3280 ¹

Abstract:
A critical problem in American rivers and streams is sedimentation. Sedimentation degrades the water quality, impairs the habitat for fish and macroinvertebrates, and limits the ecosystem functions and services of rivers and streams. In this study, we measured the community structure of the benthic communities of 18 medium sized creeks and streams in Piedmont North Carolina. This is part of a broader project studying the effectiveness of different sediment and erosion control ordinances in different jurisdictions in North Carolina. We collected general water chemistry and benthic data from all streams. We analyzed total abundance, total species richness and H' diversity for 1) all taxa, 2) EPT taxa (Ephemeroptera, Plecoptera and Tricoptera) and 3) Chironomidae. We sampled before construction began, during construction and after the construction was completed. We compared stream sites as follows: upstream (control) sites vs. the construction site to a downstream (recovery) site. Using streams as replicates to avoid pseudoreplication, we found that EPT abundance, richness and diversity were the most sensitive to sedimentation. EPT values were consistently depressed by sedimentation at the impact site during construction. The post-construction recovery at the impact site was incomplete, but improved downstream. More effective erosion and sedimentation control is needed to protect stream communities.

Keywords: Benthos; community structure; streams; sedimentation

This abstract is being presented at: 11:45 AM in session:
Oral Session #70: Aquatic Ecology.