Frank H. McCormick

Use of periphyton assemblage data as an index of biotic integrity

Periphyton assemblage data collected from 233 stream site-visits (49 in 1993, 56 in 1994, and 128 in 1995) throughout the Mid-Appalachian region were used to develop a periphyton index of biotic integrity (PIBI) based on 1) algal genera richness; 2) the relative abundances of diatoms, Cyanobacteria, dominant diatom genus, acidophilic diatoms, eutraphentic diatoms, and motile diatoms; 3) chlorophyll and biomass (ash-free dry mass) standing crops; and 4) alkaline phosphatase activity. Thirty-seven diatom genera and 38 non-diatom genera were collected. The relative richness and relative abundance (RA) of these genera were used to calculate the RA metrics of the PIBI. PIBI scores ranged from 48.0 to 85.1 among the 233 site-visits with an overall regional mean (±1 SE) of 66.1 ± 0.5. The 10 metrics and the PIBI were correlated with 27 chemical, 12 physical habitat, and 3 landscape variables. Overall, PIBI was inversely correlated with stream depth, stream water color, and Fe. Component metrics were significantly correlated with several chemical (Al, acid neutralizing capacity, Cl, Fe, Mn, N, Na, P, pH, Si, SO4, total suspended solids), physical habitat (channel embeddedness, riparian disturbances, stream depth, stream width, substrate composition), and landscape (% of the watershed in forest, agriculture, and urban land uses) variables. Canonical correlation analysis revealed significant correlations between the 10 PIBI metrics and 4 significant environmental gradients related to general human disturbances (stream acidity, stream substrate composition, and stream and riparian habitat). Analysis of variance revealed significant differences in PIBI scores for lowland vs highland streams, and among stream orders. Annual differences were explained by differences in the proportions of sampling sites in lowland streams in each year. The univariate distribution of PIBI scores was used to set threshold PIBI values for the assessment of ecological condition in Mid-Appalachian streams.

Development of an Index of Biotic Integrity for the Mid-Atlantic Highlands Region

From 1993 to 1996, fish assemblage data were collected from 309 wadeable streams in the U.S. Mid-Atlantic Highlands region as part of the U.S. Environmental Protection Agencys Environmental Monitoring and Assessment Program. Stream sites were selected with a probabilistic sampling design that allowed regional estimates of stream condition. We examined responses of 58 fish assemblage metrics to physical, chemical, and landscape indicators of disturbance. Uni- variate and multivariate analyses of relationships among fish metrics, habitat integrity, and an- thropogenic disturbance were used to develop a fish index of biotic integrity (IBI) for assessing stream condition in the entire region. Of 58 candidate metrics 9 were selected and scored contin- uously from 0 to 10; the resulting IBI was scaled so that it ranged from 0 to 100. Regional estimates of stream conditions showed that 27% of the stream length in the Mid-Atlantic Highlands had fish assemblages in good or excellent ecological condition. Of the total wadeable perennial stream length in the region 38% was fair and 14% was poor. There were insufficient data to calculate IBIs for 21% of the wadeable stream length in the Mid-Atlantic Highlands; all of these streams were small (watershed area # 2k m 2) and lacked sufficient sample size (,10 individuals) to calculate

Comparison of geographic classification schemes for Mid-Atlantic stream fish assemblages

Understanding the influence of geographic factors in structuring fish assemblages is crucial to developing a comprehensive assessment of stream conditions. We compared the classification strengths (CS) of geographic groups (ecoregions and catchments), stream order, and groups based on cluster analysis of fish assemblage data from 200 wadeable streams in the Mid-Atlantic Highlands. We 1st calculated intersite similarity indices (Bray–Curtis on relative abundance; Dice–Sørensen on presence/absence), then compared overall mean within-group similarities (W̄) with among-group similarities (B̄). We used subsets of the data to test CS from: 1) 31 reference sites defined on chemistry and habitat criteria, and 2) 21 samples from 8 sites that had been resampled within and between years to estimate the maximum similarity expected for any of the classifications. We assessed the strength of each classification by determining the degree to which W̄ was greater than B̄. Sites classified by taxonomic clusters had higher CS than did sites grouped by stream order, US Geological Survey 4-digit Hydrologic Unit Code (HUC) catchments, and ecoregions. Except for taxonomic clusters, the CS values were greater when all sites were used in the analysis than when only reference sites were used. The mean similarities for the revisits were 2 to 3 times greater than for all other classifications. We used nonmetric multidimensional scaling as an alternative approach to detecting geographic structure in the data. We found little separation of ecoregion or catchment groups except at very broad spatial scales. The relatively weak CS of any of the geographic groups suggests that the interaction of complex zoogeographic patterns and a long history of human disturbance has masked any fine-scale structure of regional fish assemblages.

Development of a Multimetric Index for Assessing the Biological Condition of the Ohio River

Abstract The use of fish communities to assess environmental quality is common for streams, but a standard methodology for large rivers is as yet largely undeveloped. We developed an index to assess the condition of fish assemblages along 1,580 km of the Ohio River. Representative samples of fish assemblages were collected from 709 Ohio River reaches, including 318 “least-impacted” sites, from 1991 to 2001 by means of standardized nighttime boat-electrofishing techniques. We evaluated 55 candidate metrics based on attributes of fish assemblage structure and function to derive a multimetric index of river health. We examined the spatial (by river kilometer) and temporal variability of these metrics and assessed their responsiveness to anthropogenic disturbances, namely, effluents, turbidity, and highly embedded substrates. The resulting Ohio River Fish Index (ORFIn) comprises 13 metrics selected because they responded predictably to measures of human disturbance or reflected desirable features of the Ohio ...

The effects of elevated metals on benthic community metabolism in a Rocky Mountain stream.

The effects of elevated metals (dissolved Zn, Mn and/or Fe) in a Rocky Mountain stream were assessed using measures of primary productivity, community respiration and water-column toxicity. Primary productivity was measured as rates of O2 evolution from natural substrates incubated in situ in closed chambers. Oxygen depletion within these chambers, when incubated in the dark, provided estimates of periphyton community respiration. Sediment community respiration on fine-grained sediments, collected and composited along each stream study reach, was measured on-site by incubating these sediments in closed chambers and measuring O2 depletion. Toxicity was measured as percent mortality of Ceriodaphnia dubia during 48 h acute tests. Gross (GPP) and net primary productivity (NPP) decreased significantly with increasing metal concentrations, from 10.88 +/- 1.46 g O2 m(-2) day(-1) to 0.83 +/- 0.20 g O2 m(-2) day(-1) and 9.85 +/- 1.43 g O2 m(-2) day(-1) to 0.81 +/- 0.20 g O2 m(-2) day(-1), respectively for the reference and most impacted site. Community respiration (CR) declined from 0.65 +/- 0.08 g O2 m(-2) day(-1) to 0.02 +/- 0.01 g O2 m(-2) day(-1) with increasing metal concentrations. Sediment community respiration (SCR) decreased from 0.26 +/- 0.02 g O2 m(-2) day(-1) to 0.01 +/- 0.01 g O2 m(-2) day(-1) at these same sites. Ceriodaphnia dubia mortality increased from 0% at the reference site to 95 +/- 5% at the most impacted sites. Net daily metabolism, quantum yield and assimilation ratio all decreased with increasing metal concentrations, suggesting that both autotrophic and heterotrophic components of the periphyton community were impaired. Overall, functional measures were able to discern sites receiving greater metal impacts from less-impacted sites, with combinations of dissolved metals explaining between 25 and 92% of the variance in the regression models. Using these regression models we were able to calculate lethal and inhibition concentrations of dissolved Zn in the Eagle River. The lethal concentration (LC50) of Zn for Ceriodaphnia dubia is 123 mg liter(-1). The concentrations of Zn which inhibited respiration (IC50) were 177 mg liter(-1) for CR and 199 mg liter(-1) for SCR. These results indicate functional measures may be as sensitive to metal concentrations as acute toxicity tests.

Chapter 23 USEPA biomonitoring and bioindicator concepts needed to evaluate the biological integrity of aquatic systems

Abstract This chapter presents the current uses, concepts and anticipated future directions of biomonitoring and bioindicators in the regulatory and research programs of the United States Environmental Protection Agency (USEPA). The chapter provides a historical look on how biomonitoring and bioindicators evolved in the USEPA or its predecessor agencies from the 1960s – 1980s, then describes two current key biomonitoring and bioindicator programmes, the USEPA Office of Research and Developments Environmental Monitoring and Assessment Programme (EMAP) and USEPAs Office of Waters Biocriteria Programme. The remainder of the chapter is organized hierarchically beginning with concepts and monitoring approaches using fish, macroinvertebrates, and periphyton assemblages, and functional ecosystem measures. The assemblage approaches are followed by current research and regulatory use of whole organism toxicity testing assessments for measuring contamination in aquatic environments and remediation assessment. The chapter includes existing and proposed activities in the use of real-time biomonitoring to assess biological exposures to contaminants and other environmental changes. A new approach that uses small and large adult whole fish tissue as a bioindicator for assessing potential contaminant exposures to wildlife is presented, followed by a description of new research in molecular approaches to biomonitoring and bioindicators through measures of gene expression, use of microarrays and measures of genetic diversity.

Response Patterns of Great River Fish Assemblage Metrics to Outfall Effects from Point Source Discharges

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