Assessment of the Impact of Heavy Metals on Benthic Communities at the Clinch River (Virginia): Evaluation of an Index of Community Sensitivity

Abstract

Benthic communities (sampled once annually from 1986 to 1989) at stations impacted by copper and zinc were characterized by reduced species richness, reduced abundance, and a shift in community composition from sensitive to tolerant taxa. Benthic community structure varied annually due to fluctuations in stream discharge and improvements in water quality. Sensitivity of 13 dominant taxa to Cu was measured in outdoor experimental streams by exposing organisms to Cu (25 μg/L) for 10 d. Sensitivities (si), defined as proportioned reduction in abundance in treated streams relative to controls, ranged from 1.00 for several species of Ephemeroptera that were completely eliminated to −0.14 for taxa that increased in treated streams (Chironomidae: Orthocladiini). An index of community sensitivity (ICS) based on si and relative abundance of dominant taxa (pi) was developed for the Clinch River. The ICS was highly sensitive to heavy metals and useful for distinguishing reference and impacted stations. There was good agreement between the ICS and other community-level approaches in identifying impacted stations. We suggest that specific ICS values, based on si estimates of dominant taxa within a region, may be employed to predict the degree of metal impact in other streams within that region.

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“…These two species were found only in one station (12 th ) associated with aquatic plants, like found in other study (Brodersen et al, 2001). Tanytarsini has correspondingly been reported as sensitive taxa (Clements and Cherry, 1988;Clements et al, 1992). In the present study, only Tanytarsini species was found at sampling site 12.…”

Effect of water quality on the feeding ecology of axolotl Ambystoma mexicanum

“…In preference experiments we found that small amounts of contaminants that do not cause physiological effects may interfere with the behaviour and thereby alter predator-prey and competitive interactions between species (Peterson et al, 2011). Contaminants, especially heavy metals, can change the outcome of competitive interactions (Clements et al, 1992;Landis et al, 1997;Pratt et al, 1997). Our results clearly show that the adverse effects of contaminants on feeding behaviour are greater on the endemic amphibian than on the exotic fish species.…”

Impacts of Copper on a Lotic Benthic Invertebrate Community: Response and Recovery

“…Reductions in mayfly taxa (Clements et al 2000), shifts in community dominance from intolerant taxa to Chironomidae (Winner et al 1980), and community changes such as reduction in species richness or abundance (Clements et al 1992, Schultheis et al 1997) have been reported. Studies have looked at impacts from multiple heavy metals (Clements and Rees 1997), as well as specific contaminants such as copper (Leland, et al 1989).…”