Title:
Bed Texture and Turbidity as Indicators of Fish Biotic Integrity in the Etowah River System
Bed Texture and Turbidity as Indicators of Fish Biotic Integrity in the Etowah River System
Author(s)
Walters, David M.
Freeman, Mary C.
Leigh, David S.
Freeman, Byron J.
Paul, Michael J.
Pringle, Catherine M.
Freeman, Mary C.
Leigh, David S.
Freeman, Byron J.
Paul, Michael J.
Pringle, Catherine M.
Advisor(s)
Editor(s)
Hatcher, Kathryn J.
Collections
Supplementary to
Permanent Link
Abstract
We sampled 32 Piedmont streams in the Etowah River system to assess the relationship between fish assemblages, bed texture, and suspended sediments. We also investigated the relationship of sediment regime to basin land cover, basin morphometry, and stream geomorphology. Index of biotic integrity (IBI) scores were positively and more
strongly related to stream slope (r = 0.81) than any
other single variable. Stream slope and bed texture
(mean phi) showed strong covariation (r = -0.92), so
they could not be analyzed as independent variables.
Stream turbidity (NTU) was negatively correlated with
IBI scores (r = -0.66), and re
_
sidual analysis showed that
turbidity accounted for a significant amount of the
variance (R2 = 0.50) in the slope-IBI regression. Both
of these turbidity relationships were nonlinear with an
apparent threshold of approximately 10 NTU. Sites
averaging higher than 10 NTU consistently had low IBI
scores and tended to have the largest negative residuals
in the slope-IBI regression.
Sponsor
Date Issued
2001-03
Extent
Resource Type
Text
Resource Subtype
Proceedings