Water Quality Monitoring Strategy Based on Agroecoregion Boundaries in the Minnesota River Basin

Project Staff: 

Principal Investigator: David J. Mulla, Professor, Department of Soil, Water, and Climate, University of Minnesota

Funding: 

USGS-WRRI 104B/ CAIWQ Competitive Grants Program

Project Duration: 

March 2005 - February 2006

Objective: 
  1. To measure the export of nutrients and sediment in minor watersheds across three different agroecoregions (Rolling Morraine, Wetter Blue Earth Till, Wetter Clays and Silts) making up the Blue Earth, Le Sueur, and Watonwan watersheds of south central Minnesota.
  2. To evaluate the variability in export of nutrients and sediment in minor watershed within three agroecoregions (Rolling Morraine, Wetter Blue Earth Till, Wetter Clays and Silts) of south central Minnesota.
Summary: 

The project hypothesized that water quality impairment is primarily driven by factors accounted for by agroecoregion boundaries, including major cropping system types, slope steepness, soil internal drainage, and mean annual precipitation. Within agroecoregion boundaries, at the scale of minor watersheds (watersheds encompassed by an 8-digit HUC), water quality impairment will vary primarily in response to the spatial variability in slope steepness, and density of animal units in feedlots. We hypothesize that the variability in water quality is greater for minor watersheds across different agroecoregions than for minor watersheds within agroecoregions.