In addition to providing habitat for a broad suite of wetland-dependent wildlife species, prairie pothole wetlands confer a variety of ecological good and services to society. Ecosystem services are the benefits to people from nature. These benefits include food, water purification, carbon sequestration, soil stabilization, recreation, cultural values, among others. The contribution of natural ecosystems to these benefits is often un-quantified and unmeasured, but the value of such benefits is gradually becoming more apparent as human populations grow and demand for natural resources increases.
Surface water storage and flows—Prairie wetlands store water during spring runoff and following prolonged precipitation events. Slowing runoff rates reduce annual economic losses from flood damage to infrastructure such as roads, drainage systems, and housing/structures. Wetland losses in the upper reaches of the Mississippi River watershed have been proven to increase, in part, the magnitude of flood events along the Mississippi River.
Groundwater recharge—Surface waters contained within prairie potholes interact with ground water in a variety of ways. Subsurface connectivity of water flow affects both water chemistry and a variety of biological processes. Potholes can be both areas of local recharge to groundwater and areas where groundwater discharges to the surface. They can also be important for recharging regional aquifers.
Controls for contaminants, excess nutrients, and sediments—Prairie potholes often receive substantial inputs of chemicals, excess nutrients, and sediments from surrounding agricultural or other industrial operations. In some cases wetlands are able to incorporate undesirable chemicals and breakdown these compounds into less toxic by-products and sediments. Excess nutrient inputs to wetlands are incorporated into wetland flora and fauna, thereby improving downstream water quality. Further, wetlands reduce peak river flows allowing sediments to settle out of the water column, which reduces stream turbidity.
Greenhouse gas flux—Prairie potholes have been documented to be important carbon stores. Thus, restoration of wetlands within the PPR could help mitigate green house gas emissions.
Restoring ecological goods and services through wetland restoration—It is possible to restore some ecological functions associated with prairie potholes including peak river flow reductions, removal of nitrogen and phosphorous. However, recent meta analyses of 621 wetland sites through-out the world indicate that biological structure and biogeochemical function in restored wetlands was 26% and 23% lower respectively than wetlands that have not been drained. Furthermore, this study also found that depressional wetlands and wetlands in colder climates, such as the PPR, are the slowest to recover full ecological functions.
For further information, including citations for facts above, please read the in-press book chapter by Doherty, Howerter, Devries, & Walker in the new book Wetlands of the World. Or, learn more about ecosystem services from the Ecological Society of America factsheet.
Researchers within the USPPR are continuing research to better understand ecosystem services. See examples within our Resources section.