Increasing atmospheric carbon dioxide concentrations since the Industrial Revolution have led to a decrease in pH and acidification of the ocean. The aim of this study is to investigate if ocean acidification will enhance the release of metals from coastal sediments. Sediment cores from a contaminated urban estuary were incubated for two months at pH values of 7.2, 7.6 and 7.8 (the control). The overlying water was analyzed for dissolved trace metals to determine if the changes over time were influenced by pH. There was a flux of copper, iron, lead, zinc, but not manganese in all treatments. There was no significant variation in flux or redox zone depth with pH treatment. Rather it seems that benthic organism activity and sediment heterogeneity are more important in influencing the release of metals from sediments. Experimental results provide new information on the long-term fate of contaminated sediments in coastal waters.
Uter M. C., 2014. The impact of ocean acidification on metal contaminated marine sediment. MSc thesis, University of New Hampshire, 94 pp. Thesis (subscription required).
