With the present summer weather, it’s hard to recall the temperatures last February when it was cold enough to form 7 inches of solid ice on Oyster Pond. The ice surface provided a stable platform for scientists from the US Geological Survey and the Woods Hole Oceanographic Institution to collect sediments from the pond. The photograph shows the well insulated team preparing to lower a 20-foot fiberglass pipe through a hole in the ice to collect an undisturbed core of sediment about 3 feet long.
The goal of the research is to measure changes in the atmospheric deposition of contaminants to Oyster Pond over the last century. The main focus is mercury, an element that is present in many fresh water fish at concentrations above advisory limits for consumption by humans in many parts of the United States, including Cape Cod. There is some expectation that the rate of mercury deposition has decreased during the last decade in response to regulations set by the U.S. Environmental Protection Agency to reduce mercury emissions from combustion of municipal and medical wastes. Emissions from coal-fired power plants in the US are still a major source of mercury to the atmosphere as are the growing number of power plants in developing countries like India and China.
The USGS-WHOI research team is also analyzing resident and migratory fish from Oyster Pond in order to evaluate the biological burdens of mercury in this coastal environment. The overall effort to understand more about the cycling of mercury between air, water, sediment, and living organisms is coordinated with programs conducted by the Massachusetts Department of Environmental Protection in ponds on the outer Cape and at other locations within Massachusetts. by Dr. Michael H. Bothner (from the Summer 2007 OPET newsletter)