Fate of Metal Contaminants in Streams
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Changing Stream and Riparian Corridor, Pinal Creek, AZ.
Investigators/Collaborators
- Jud Harvey, USGS, Reston, VA
- Chris Fuller, USGS, Menlo Park, CA
- James Brown, USGS, Tucson, AZ
- Martha Conklin, U. Arizona, Tucson, AZ
- Brian Wagner, USGS, Menlo Park, CA
Current Questions:
- What is the role of expanding coverage of stream aquatic vegetation in changing the patterns and rates of solute transport and solute reactions? From 1994 to present a ten-fold increase was observed in solute storage capacity of the stream ecosystem, along with a greater removal of metals (with M. Conklin, C. Fuller, J. Brown, and others).
- Does aquatic vegetation stimulate oxidation and/or sorption of metals from streamflow? What is the importance of direct removal of metals by incorporation into plant tissue? (with M. Conklin, C. Fuller, J. Brown, and others).
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(left) Maganese oxides and carbonates from streambed.
(right) Intact 20-cm core from streambed showing elevated levels of manganese coatings (black sediment) in top 5-cm.
Past Highlights:
- Centimeter-scale hyporheic zones beneath the streambed interface remove a significant fraction of dissolved manganese released by mining activities in basin (Harvey and Fuller, 1998).
- Removal of trace metals (Ni, Co, Zn) from streamflow coupled to manganese oxidation in hyporheic zone (Fuller and Harvey, 2000).
Funding Acknowledgements: