British Journal of Environment and Climate Change, ISSN: 2231-4784,Vol.: 3, Issue.: 1 (January-March)-Special Issue
Original Research Article Special Issue
Assessing Effects of Climate Change on Biogeochemical Cycling of Trace Metals in Alluvial and Coastal Watersheds
Ming-Kuo Lee1*, Michael Natter1, Jeff Keevan1, Kirsten Guerra1, James Saunders1, Ashraf Uddin1, Munir Humayun2, Yang Wang2 and Alison R. Keimowitz3
1Department of Geology and Geography, Auburn University, Auburn, AL, 36839, United States.
2Department of Earth, Ocean and Atmospheric Science, Florida State University, Tallahassee, FL 32306, United States.
3Department of Chemistry, Vassar College, Poughkeepsie, NY, 12604, United States.
Assessing the impacts of climate changes on water quality requires an understanding of the biogeochemical cycling of trace metals. Evidence from research on alluvial aquifers and coastal watersheds shows direct impacts of climate change on the fate and transformation of trace metals in natural environments. The case studies presented here use field data and numerical modeling techniques to test assumptions about the effects of climate change on natural arsenic contamination of groundwater in alluvial aquifers and mercury bioaccumulation in coastal salt marshes. The results show that the rises of sea level and river base during the warm Holocene period has led to an overall increase in groundwater arsenic concentration due to the development of reducing geochemical conditions and sluggish groundwater movement. Modeling results indicate that the intrusion of seawater occurring during high sea-level stand may lead to desorption of arsenic from surface of hydrous oxides due to pH effects and ionic competition for mineral sorbing sites. Our results also show that contamination and bioaccumulation of Hg and other metals in estuarine and coastal ecosystems may be influenced by climate-induced hydrologic modifications (atmospheric deposition, riverine input, salinity level, etc.).
Biogeochemical cycle; climate change; sea level rise; trace metals; arsenic; mercury; alluvial aquifers; groundwater; saltwater intrusion; salt marsh; bacterial iron reduction; bacterial sulfate reduction.
Full Article - PDF
DOI : 10.9734/BJECC/2013/3061