Prairie PotholesThe Prairie Pothole Guidebook is designed to assess the functions of depressional, palustrine, herbaceous, temporarily and seasonally ponded wetlands formed in glacial till. The geographic area of interest is commonly referred to as the Prairie Pothole Region (PPR). The PPR is large and contains waters and wetlands of numerous hydrogeomorphic subclasses. The dominant hydrologic inputs to temporary and seasonal prairie pothole wetlands are surface runoff of snowmelt and early spring rains that do not infiltrate into the frozen upland soils. The dominant hydrologic output is evapotranspiration; a secondary output is downward seepage (i.e., groundwater recharge). The dominant hydrodynamics are vertical. The complete descriptor of this subclass is: prairie potholes, low permeability substrate, temporary and seasonal hydroperiods, depressions. Two important distinctions for use of this guidebook are: First, this subclass does not include wetlands developed in coarse textured (i.e., sandy) parent materials (such as glacial outwash) because these wetlands are in a different hydrogeologic setting and second, this subclass does not include larger wetlands with semi-permanent (or wetter) hydrologic regimes. Guidebooks:Gilbert, M.C., Whited, P.M., Clairain, E.J., and Smith, R.D. (2006). "A Regional Guidebook for Applying the Hydrogeomorphic Approach to Assessing Wetland Functions of Prairie Potholes," ERDC/EL TR-06-5, U.S. Army Engineer Research and Development Center, Vicksburg, MS. (FCI Calculator)
Web Date: October 1997 |
