Grantee Research Project Results
Microbial Community Diversity, Structural and Functional Responses to Multi-Component Metal Contamination of River Benthic Systems
EPA Grant Number: R829400E02Title: Microbial Community Diversity, Structural and Functional Responses to Multi-Component Metal Contamination of River Benthic Systems
Investigators: Holben, William E. , Gannon, James , Moore, Johnnie , Rillig, Matthias
Current Investigators: Gammons, Christopher H. , Hobbs, David , Nimick, David , Moore, Johnnie
Institution: University of Montana
Current Institution: University of Montana , United States Geological Survey
EPA Project Officer: Chung, Serena
Project Period: September 24, 2001 through September 23, 2003 (Extended to September 22, 2004)
Project Amount: $280,000
RFA: EPSCoR (Experimental Program to Stimulate Competitive Research) (2000) RFA Text | Recipients Lists
Research Category: EPSCoR (The Experimental Program to Stimulate Competitive Research)
Objective:
The research will develop detailed information about the composition, physiological activities, and chemical environment of microbial communities in river sediments contaminated with mine wastes. Experiments are designed to test 5 hypotheses: 1) initial exposure to metals inhibits or kills sensitive organisms, leaves tolerant populations as dominant, and produces an initial net decrease in diversity; 2) gradual changes in microbial community structure and function occur as the resident community becomes more tolerant of metals contamination; 3) decreased apparent toxicity from metal contamination occurs with prolonged exposure as a result of increased tolerance; 4) bacterial community changes can be indicative of the ecological health of watersheds because of the primary role bacteria play in biogeochemical processes and their basal position in ecosystem trophic structure; and 5) microbial communities respond to perturbation through changes in abundance of specific populations, or through altered patterns of physiological/metabolic activity.
Approach:
The effects of metal contamination on microbial community diversity, structure, and function will be analyzed using geochemical and molecular techniques in a study whose features include: 1) combined field and mesocosm experiments to separate natural variation effects from metal effects; 2) assessment of the fungal component of microbial communities; and 3) assessment of the utility of monitoring bacterial communities as indicators of ecosystem health. Field-based research compares microbial communities in sites with varied levels of metals contamination using metals-impacted test-sites within the Clark Fork watershed in western Montana and similar unimpacted reference sites. Sediments at each site will be geochemically characterized seasonally in conjunction with detailed microbial community analyses. In situ experiments include biomass, lipid, activity analyses, and molecular biology methods to determine microbial community structure and function.
Expected Results:
The overarching goal is to determine the effects of multi-component metal contamination on the structure and function of microbial communities in riverine sediments and to apply this knowledge to the development of strategies to accurately gauge injury to natural resources and monitor the effectiveness of remediation efforts. The connection between microbial stress and ecosystem productivity means that monitoring microbial community structure and function can provide important information on overall ecosystem health and underpin important ecological management decisions. This research will produce improved risk assessment of metals contamination in rivers and also facilitate better monitoring tools for different management or remediation practices at a fundamental ecosystem level based on bacterial community indicators.
Publications and Presentations:
Publications have been submitted on this project: View all 36 publications for this projectJournal Articles:
Journal Articles have been submitted on this project: View all 11 journal articles for this projectSupplemental Keywords:
microbial community, heavy metal, DNA, mining, restoration, indicators, Montana., RFA, Ecosystem Protection/Environmental Exposure & Risk, Scientific Discipline, INTERNATIONAL COOPERATION, INDUSTRY, Geographic Area, Waste, Water, POLLUTANTS/TOXICS, Hazardous, Industrial Processes, EPA Region, Fate & Transport, State, Environmental Chemistry, Microbiology, Monitoring/Modeling, Hazardous Waste, Arsenic, Chemicals, Ecology and Ecosystems, Environmental Monitoring, Water Pollutants, heavy metals, contaminant transport, mining, mining impacted watershed, Montana , fate and transport , mining wastes, Region 8, aquatic ecosystem, groundwater contamination, monitoring, contaminant dynamics, groundwater, fate and transport, analytical chemistry, chemical kinetics, contaminant transport models, chemical transport models, chemical releases, mine tailingsProgress and Final Reports:
The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.