Bioaccumulation of Mercury in Riverine Periphyton

摘要

In aquatic ecosystems, algae are the primary producers and the base of the food web. To date, there has been little research on the role of benthic algae (periphyton) in the bioaccumulation of mercury (Hg) in riverine systems -- a key step of the process of bioaccumulation from the physical environment (water and sediments) to higher aquatic organisms (invertebrates, fish, and others). Periphyton has been shown to have an important role in the transfer of mercury in wetlands of the Florida Everglades and in some situations served as the host site for mercury methylation, which is the key process controlling mercury toxicity in the environment. Pickhardt and others (2002) found that algal blooms in lakes resulted in reduced bioaccumulation of mercury in algal- rich eutrophic lake systems due to decreases in the concentration of mercury per algal cell.