- How does nutrient loss occur in Iowa agriculture?
- Which practices reduce nutrient loss?
- Are these practices being adopted?
Nowatzke explained that agricultural losses of nitrogen and phosphorus mainly occur in two different ways: soil and phosphorus loss through erosion from surface runoff and loss of nitrate-nitrogen and some dissolved phosphorus through subsurface drainage. In-field and edge-of-field practices have been designed and are being adopted by farmers and landowners to reduce these losses.
These practices can be used to meet the nutrient reduction goals set forth in the Iowa Nutrient Reduction Strategy. The Strategy lays out several different scenarios in which the goals can be reached through different combinations of practices and the necessary adoption rate for each scenario. One of these scenarios is shown in the figure below, with the current estimated adoption rate also shown.
More widespread adoption of these practices (in this combination of practices or in the other scenarios) will be needed to reach the nutrient reduction goals of the Iowa Nutrient Reduction Strategy.
Nowatzke shared the following resources for more information:
- Iowa Nutrient Reduction Strategy
- Reducing Nutrient Loss: Science Shows What Works
- Whole Farm Conservation Best Practices Manual
More information about the progress toward Iowa’s water quality goals can be found in the forthcoming 2018-19 Annual Progress Report of the Iowa Nutrient Reduction Strategy. Last year’s report can be found here.
Watch the full webinar here!
Be sure to join us next week, on May 6, when Ross Evelsizer, Watershed Planner & GIS Specialist at Northeast Iowa RC&D, will present a webinar titled: “Multi-Cropping as a Profitable Soil Health Solution“.