PUBLICATIONS

• Publications by topic
  • Groundwater
  • Surface Water
  • Water Quality
  • Water Use

• Publications by date
  • Recent publications

Annual Water Data Report

USGS Publications Warehouse

USGS IN YOUR STATE

USGS Water Science Centers are located in each state.

Effects of urbanization on the condition of streams in the Piedmont of North Carolina--Responses of benthic macroinvertebrate assemblages

Poster
By Thomas F. Cuffney, Douglas A. Harned, Gerard McMahon, and Elise M.P. Giddings

Abstract

The effects of urbanization on the physical, chemical, and biological characteristics of streams in the North Carolina Piedmont were investigated as part of the U.S. Geological Surveys National Water-Quality Assessment (NAWQA) Program. Over 1,200 candidate basins (2-3rd order streams) were identified using a 30-m digital elevation model. A multimetric urban intensity index (UII) derived from population, infrastructure, land use, land cover, and socioeconomic factors was used to characterize the degree of urbanization in each baisn. Candidate basins were grouped together based on natural features (e.g., ecoregion, elevation, relief, and soil characteristics) and a subset of 30 basins was selected for study on the basis of uniformity in natural features, representation of the urban gradient (i.e., low to high UII), and accessibility.

Biological (fish, benthic macroinvertebrates, and algae), physical (stream stage, temperature, and habitat), and chemical (nutrients, pesticides, and major ions) characteristics were measured in each stream and related to changes in the UII. Biological responses were assessed using multivariate (i.e., assemblage ordinations) and multimetric (i.e., assemblage metrics) methods. The relations between invertebrate responses, the UII, and characteristics of urbanization are described in this paper. These relations were examined using correlations and regressions.

Invertebrate assemblages exhibited strong responses to the UII based on ordination site scores (Y = -0.013X + 1.613, R2 = 0.78, P < 0.001) and assemblage metrics (e.g., EPT richness Y = -0.165X + 17.004, R2 = 0.78, P < 0.001 and richness-based tolerance Y = 0.013X + 5.047,R2 = 0.75, P < 0.001). The relations between invertebrate responses and UII were linear and did not show any initial resistance to urbanization. Response rates in the North Carolina Piedmont were similar to response rates reported for the Boston, MA (ordination -0.016, EPT richness -0.268, tolerance 0.015), Birmingham, AL (ordination -0.017, EPT richness -0.168, tolerance 0.015), and Salt Lake City, UT (ordination -0.012, EPT richness -0.169, tolerance 0.021) metropolitan areas based on previous NAWQA Program urban gradient studies.

Cuffney, T.F., Harned, D.A., and Giddings, E.M., 2004, Effects of urbanization on the condition of streams in the Piedmont of North Carolina--Responses of benthic macroinvertebrate assemblages: AGU 2004 Fall Meeting, December 13-17, 2004, San Francisco, California: Supplement to Eos, Transactions, American Geophysical Union, v. 85, no. 47, Abstract B11B-0146 [poster].