Assessing Wetland Changes in the Prairie Pothole Region of Minnesota From 1980 to 2007

Abstract

Wetlands in the Minnesota Prairie Pothole Region are critical landscape elements because of their unmatched importance to breeding waterfowl, and other wildlife. They provide vast benefits to store runoff or act as nutrient sinks and offer other environmental and socio-economic returns. Data on location, extent and types of wetlands collected by the U.S. Fish and Wildlife Service National Wetlands Inventory is used for developing conservation strategies and evaluating net landscape changes affecting fish and wildlife populations. Minnesota wetlands were mapped 27 y ago by the National Wetlands Inventory. We examined 176 10.2-km2 (4-mi2) sample plots in the Minnesota Prairie Pothole Region, using aerial photo interpretation techniques, to determine the current accuracy of the National Wetlands Inventory data used in the eastern Prairie Pothole Region for conservation planning and evaluation. We stratified our analysis by Bailey's (1995) Ecological Subsections. We estimated that across the entire Minnesota Prairie Pothole Region 4.3% of wetland area has been lost since 1980 with losses varying from 0 to 15% among Ecological Subsections. Implications of these findings suggest that National Wetlands Inventory data should be regularly updated in areas subject to rapid wetland change.

Projected wetland densities under climate change: habitat loss but little geographic shift in conservation strategy

“…Partially drained wetlands were excluded as these are often subsequently fully drained (Oslund et al. ). The land‐use and wetland basin covariates were assumed to be static among years because available data do not capture land conversion and wetland drainage over the time scale of our study.…”

Evidence for 20th century climate warming and wetland drying in the North American Prairie Pothole Region

“…Approximately half of the natural wetland basins in the PPR were drained many decades ago for agricultural and urban uses (Tiner 1984; Dahl 2000, 2006, 2011). The proportion of wetlands drained follows the moisture (and hence cropland productivity) gradient; nearly all prairie wetlands in the subhumid climate of Iowa and western Minnesota have been drained, while at present the majority remain intact in the drier, central Dakotas and in the western Canadian Prairies (Johnson et al 2008), although drainage has continued in both areas (Environment Canada 1991; Dahl and Watmough 2007; Bartzen et al 2010; Oslund et al 2010). Furthermore, the ecological functions of many remaining wetlands have been impacted by invasive species, habitat conversion, overgrazing, and by farming in dry years (Gleason and Euliss 1998; Guntenspergen et al 2002; Gleason et al 2003; van der Valk 2006).…”

Delineating wetland catchments and modeling hydrologic connectivity using lidar data and aerial imagery

“…The PPR is considered as one of the largest and most productive wetland areas in the world, which serves as a primary breeding habitat for much of North America's waterfowl population (Keddy, 2010;Steen et al, 2014;Rover and Mushet, 2015). The wetland depressions, commonly known as potholes, possess important hydrological and ecological functions, such as providing critical habitat for many migrating and breeding waterbirds (Minke, 2009), acting as nutrient sinks (Oslund et al, 2010), and storing surface water that can attenuate peak runoff during a flood event (Huang et al, 2011b). The potholes range in size from a relatively small area of less than 100 m 2 to as large as 30 000 m 2 , with an estimated median size of 1600 m 2 (Zhang et al, 2009;Huang et al, 2011a).…”