Algal bioassessment metrics for wadeable streams and rivers of Maine, USA

Freshwater Science
By: , and 



Many state water-quality agencies use biological assessment methods based on lotic fish and macroinvertebrate communities, but relatively few states have incorporated algal multimetric indices into monitoring programs. Algae are good indicators for monitoring water quality because they are sensitive to many environmental stressors. We evaluated benthic algal community attributes along a landuse gradient affecting wadeable streams and rivers in Maine, USA, to identify potential bioassessment metrics. We collected epilithic algal samples from 193 locations across the state. We computed weighted-average optima for common taxa for total P, total N, specific conductance, % impervious cover, and % developed watershed, which included all land use that is no longer forest or wetland. We assigned Maine stream tolerance values and categories (sensitive, intermediate, tolerant) to taxa based on their optima and responses to watershed disturbance. We evaluated performance of algal community metrics used in multimetric indices from other regions and novel metrics based on Maine data. Metrics specific to Maine data, such as the relative richness of species characterized as being sensitive in Maine, were more correlated with % developed watershed than most metrics used in other regions. Few community-structure attributes (e.g., species richness) were useful metrics in Maine. Performance of algal bioassessment models would be improved if metrics were evaluated with attributes of local data before inclusion in multimetric indices or statistical models.

Study Area

Publication type Article
Publication Subtype Journal Article
Title Algal bioassessment metrics for wadeable streams and rivers of Maine, USA
Series title Freshwater Science
DOI 10.1899/10-162.1
Volume 30
Issue 4
Year Published 2011
Language English
Publisher University of Chicago Press
Contributing office(s) Coop Res Unit Leetown
Description 16 p.
First page 1033
Last page 1048
Country United States
State Maine
Google Analytic Metrics Metrics page
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