PARENT SESSION
WA9 - Role of Biomarkers/Bioindicators in Ecological Risk Assessment
Chair: Adams, Marshall1, 1 PO Box 2008, Bld. 1505, Oak Ridge, TN, USA
Co-chair: Zelikoff, Judith2, 2 57 Old Forge Rd., Tuxedo, NY, USA
8:00 AM to 12:00 PM - Wednesday, 20 November 2002
Room Ballroom E
(572) A Multivariate and GIS Analysis of Molecular and Ecosystem Indicators of Stress in Sierra Nevadan Lakes.
McClain, Scott McClain*,1, Aaron, Roberts1, Miller, Glenn2, Allen, Brant3, Guttman, Sheldon1, Oris, James1, 1 Miami University, Oxford, OH, USA2 University of Nevada, Reno, NV, USA3 University of California, Davis, CA, USA
ABSTRACT- Alpine lake ecosystems have come under increased detrimental environmental pressure because of development and recreational activity. This study surveyed 16 lake sites on and around the Lake Tahoe, CA region of the Sierra Nevada. The goal was to collect observational, biological, chemical, and physical data for riparian, shoreline, and surface water of each site. In addition, 25 caged rainbow trout were exposed at each site for 48 hr to act as sentinel organisms from which molecular biomarker responses could be measured. Molecular biomarkers for five transcriptionally inducible genes, in gill and liver, were measured from exposed trout. Data was analyzed using principle component analysis for separation of important variables, which were then used to sort lakes by impairment score. Results suggested that there were differential biomarker responses relative to environmental impact variables for three biomarkers; activin, CYP1A1, and multiple xenobiotic resistant (MXR) genes. Specific biomarkers in trout provided biological indicators of contaminant contact that could facilitate locating specific type and intensity of potential impairment. Geographical information systems (GIS) analysis was used to incorporate the physical and biological data into a comprehensive display of the variation in environmental impact observed in these lakes. GIS provided a means by which selected indicator variables could be associated within the context of the unique Sierra geography. Within the boundaries of this study there were wide ranging differences in level of environmental impact that included disruption of native habitat and contaminant exposure to ecologically important fish species. The addition of molecular biomarkers of contaminant exposure contributed to the standardized ecological assessment of lakes and may help direct future strategies for limiting habitat destruction.
Key words: biomarkers, multivariate, GIS, molecular