Wetlands

The Prairie Pothole Region (PPR), composed of grasslands and farmland and interspersed with shallow wetlands, occurs over a major portion of the PCOR Partnership region. In the United States, the PPR includes portions of Iowa, Minnesota, Montana, North Dakota, and South Dakota, and in Canada, the PPR includes portions of Alberta, Saskatchewan, and Manitoba.¹ Prior to European settlement, this region may have supported more than 48 million acres of wetlands, making it the largest wetland complex in North America. However, the wetlands contained fertile soils which were extensively cultivated. Cultivation of the wetlands led to the loss of stored soil carbon through the oxidation of organic matter (the carbon in the soil combined with oxygen in the atmosphere to form CO₂).

Restoring wetlands can sequester large amounts of carbon as demonstrated in recent work by U.S. Geological Survey and Ducks Unlimited scientists for the PCOR Partnership. Studies at PPR sites demonstrated that restoration of previously farmed wetlands results in the rapid replenishment of soil organic carbon that had been lost to cultivation. On average, restored wetlands gained carbon at an annual rate of 1.1 tons per acre per yr.^1,2 The finding that restored prairie wetlands are important carbon sinks provides a unique and previously overlooked opportunity to store atmospheric carbon in the PCOR Partnership region.

References:

1. Mann, G.E., 1974, The Prairie Pothole Region - zone of environmental opportunity: Naturalist, v. 25, no. 4, p. 2, C. 7.
2. Gleason, R.A., Euliss, N.H., Jr., McDougal, R., Kermes, K.E., Steadman, E.N., and Harju, J.A., 2005, Potential of restored prairie wetlands in the glaciated North American prairie to sequester atmospheric carbon: Plains CO₂ Reduction (PCOR) Partnership topical report for U.S. Department of Energy and multiclients, Grand Forks, North Dakota, Energy & Environmental Research Center, July 2005.