Drainage Water Quality Impacts of Various In-field Nutrient Management Practices: Agriculture Drainage Research and Demonstration Site - Gilmore City
Download Full Text
Research focused on the effects of nitrogen (N) management on crop production and tile drainage water quality has been conducted in north-central Iowa near Gilmore City since 1989. The research site ag drainage well (ADW) includes 72 individually drained plots that are 50 feet wide and 125 feet long (Figures 1 and 2). Tile lines were installed at a depth of 3.5 feet spaced 25 feet apart. The center tile line from each plot is pump monitored continuously for drainage volume with a flow meter and a flow-proportional sample is passively collected for nitrate-nitrogen (nitrate-N) and dissolved phosphorus (P) analysis (Figure 3). Drainage flow is recorded and water samples are collected for analysis weekly. Soil types at ADW include Nicollet, Webster and Canisteo, all of which are clay loams. The 30-year average annual rainfall for ADW is 33.5 inches.
Helmers, Matt, "Drainage Water Quality Impacts of Various In-field Nutrient Management Practices: Agriculture Drainage Research and Demonstration Site - Gilmore City" (2017). Extension and Outreach Publications. 573.
Iowa State University Extension and Outreach publications in the Iowa State University Digital Repository are made available for historical purposes only. The information contained in these publications may be out of date. For current publications and information from Iowa State University Extension and Outreach, please visit