Quantifying the effects of decreasing water levels on carbon storage in Great Lakes coastal wetlands.

Abstract

As the concentration of carbon dioxide increases in the atmosphere, it is critical to assess the natural reservoirs in which carbon can be stored. Soils contain the third largest pool of carbon, behind geologic and oceanic pools, and store a disproportionate amount of carbon due to anaerobic conditions. Wetland soils in the Great Lakes region in particular are a potentially significant pool of carbon that has yet to be thoroughly studied and quantified. This study attempted to measure the carbon pools of the swamp, transitional, and wet meadow vegetation zones of three protected embayment wetlands located in eastern half of Michigan’s Upper Peninsula. The relationship between soil C and vegetation zone was evaluated, as well as the relationship between soil C and tree basal area. An average of 53.22 kg/m3 of soil C was found within the three wetlands studied, suggesting that Great Lake coastal wetlands may hold a disproportionally large amount of carbon. This study found no significant difference between soil C within the three zones, nor did it find a significant relationship between soil C and tree basal area. Future studies should examine the possible mechanisms that would contribute to variability in soil C in the Great Lakes region to better define ways in which soil C may change as lake water levels decrease.