title: The Use of Field and Mesocosm Experiments to Quantify Effects of Physical and Chemical Stressors in Mining-Contaminated Streams.
abstract: Identifying causal relationships between acid mine drainage (AMD) and ecological responses in the field is challenging. In addition to the direct toxicological effects of elevated metals and reduced pH, mining activities influence aquatic organisms indirectly through physical alterations of habitat. The primary goal of this research was to quantify the relative importance of physical (metal-oxide deposition) and chemical (elevated metal concentrations) stressors on benthic macroinvertebrate communities. Mesocosm experiments conducted with natural assemblages of benthic macroinvertebrates established concentration-response relationships between metals and community structure. Field experiments quantified effects of metal-oxide contaminated substrate and showed significant differences in sensitivity among taxa. To predict the recovery of dominant taxa in the field, we integrated our measures of metal tolerance and substrate tolerance with estimates of drift propensity obtained from the literature. Our estimates of recovery were consistent with patterns observed at downstream recovery sites in the NFCC, which were dominated by caddisflies and baetid mayflies. We conclude that mesocosm and small-scale field experiments, particularly those conducted with natural communities, provide an ecologically realistic complement to laboratory toxicity tests. These experiments also control for the confounding variables associated with field-based approaches, thereby supporting causal relationships between AMD stressors and responses.
authors.affiliation: Department of Fish, Wildlife and Conservation Biology, Colorado State University , Fort Collins, Colorado 80523, United States.|Colorado Parks and Wildlife, 317 W. Prospect Rd, Fort Collins, Colorado 80526, United States.
authors.forename: Pete
authors.initials: P
authors.lastname: Cadmus
authors.affiliation: Department of Fish, Wildlife and Conservation Biology, Colorado State University , Fort Collins, Colorado 80523, United States.
authors.forename: William H
authors.initials: WH
authors.lastname: Clements
authors.affiliation: Department of Chemistry and Geochemistry, Colorado School of Mines , Golden, Colorado 80401, United States.
authors.forename: Jacob L
authors.initials: JL
authors.lastname: Williamson
authors.affiliation: Department of Chemistry and Geochemistry, Colorado School of Mines , Golden, Colorado 80401, United States.
authors.forename: James F
authors.initials: JF
authors.lastname: Ranville
authors.affiliation: Department of Chemistry and Geochemistry, Colorado School of Mines , Golden, Colorado 80401, United States.|Applied Limnology Professionals, LLC, 414 Anvil Way, Golden, Colorado 80401, United States.
authors.forename: Joseph S
authors.initials: JS
authors.lastname: Meyer
authors.affiliation: Department of Soil & Physical Science, Lincoln University , Canterbury, New Zealand.
authors.forename: María Jesús
authors.initials: MJ
authors.lastname: Gutiérrez Ginés
mesh_terms: D000143:Acids; D000818:Animals; D004463:Ecology; D017753:Ecosystem; D004784:Environmental Monitoring; D007313:Insecta; D007448:Invertebrates / Q000187:drug effects; D008670:Metals / Q000032:analysis; D008906:Mining; D045483:Rivers; D014874:Water Pollutants, Chemical / Q000032:analysis
chemical_list: D000143:Acids; D008670:Metals; D014874:Water Pollutants, Chemical