Research Progress Reported by Iowa Nutrient Research Center at Iowa State

January 22nd, 2015

AMES, Iowa — Two sets of progress reports are now available online for research projects funded through the Iowa Nutrient Research Center at Iowa State University.

One set is the first quarterly reports for projects funded for 2014-2015. The other is year-end reports for 10 projects funded for 2013-2014.

The projects are conducted by scientists at Iowa State, the University of Iowa and University of Northern Iowa. Each addresses critical needs or gaps in nitrogen and phosphorus research identified in the science assessment that was part of the Iowa Nutrient Reduction Strategy. The strategy is a science and technology-based approach to assess and reduce nutrients delivered to Iowa waterways and the Gulf of Mexico.

Progress highlights on new projects funded for 2014-2015 include:

  • Two projects are studying watersheds to determine factors that impact nutrient loading. One will repeat a survey to track farming practices in the Walnut Creek watershed that was originally conducted from 1991 to 1994. The other involves the development of a statistical model to describe changes in seasonal concentrations and loads of nitrate in the Raccoon River from 1974 to the present.
  • Two projects are evaluating remote sensing as a method of determining land use and cropping practices. One is developing protocols to inventory cover crops and residue cover. The other is doing the same for riparian buffers and grassed waterways.
  • Three projects are evaluating in-field and edge-of-field practices on soil and nutrient loss. In one, 570 soil samples have been obtained and analysis is underway to determine phosphorus loss in 12 Iowa watersheds. Another involves ongoing water quality sampling from 36 crop plots on an ISU research farm. The third involves continuous water quality monitoring of two sub-watersheds of Rapid Creek near Iowa City.
  • Two projects use modeling to better understand water, soil and nutrient movement in a watershed. The Catfish Creek Watershed near Dubuque is a pilot watershed to develop the scientific basis for a nutrient trading program. Model development also is underway in both the Cedar and Turkey rivers. On the Cedar, research is focused on understanding the impact of tile drainage on stream flow and the incorporation of field terraces. The model on the Turkey River has several aspects, with one focused on phosphorus.

Progress highlights on projects funded for 2013-2014 include:

  • A project is conducting extensive fieldwork and water sampling in the Cedar River watershed. Eighteen sites were sampled weekly from April through October for stream water and sediments, and 30 sets of samples have been collected and analyzed. This baseline data will be useful in studying the actual nutrient loading to the Cedar River during periods of high flow in relation to land use practices.
  • A saturated buffer was installed in September in Tama County as part of the Benton-Tama Nutrient Reduction Demonstration Project. Monitoring wells were installed to assess nitrate in shallow groundwater down-gradient from the distribution tile. Researchers are installing a second saturated buffer in Blackhawk County as part of the Miller Creek Water Quality Improvement Project.
  • The goal of one project is to provide farmers with solid financial information and user-friendly tools to help them make decisions about adopting effective non-point source best management practices. Nutrient reduction strategy spreadsheets for best management practices are complete. ISU Extension and Outreach’s water quality team and farm management specialists are assessing the nitrogen-based part of the tool, with the phosphorus section still under development.
  • Weekly sampling of six pilot-scale bioreactors began with the onset of flow in May. Samples were taken at the inlet and outlet of the bioreactors. Three of the bioreactors were managed to have high retention times, with the other three managed to have high flow volumes. Scientists are compiling and analyzing flow data.

The website for the Iowa Nutrient Research Center provides more details of all funded projects, plus quarterly progress reports. The website,, is part of the Iowa Nutrient Reduction Strategy website.

The Iowa Nutrient Research Center was established in 2013 by the Iowa Board of Regents in response to legislation passed that spring by the Iowa Legislature and signed by Governor Terry Branstad. The center received $1.5 million for 2013-2014, and another $1.3 million for 2014-2015, for research evaluating the performance of current and emerging nutrient management practices, providing recommendations on implementing the practices and developing new practices.

The center’s director is John Lawrence, associate dean for extension and outreach in Iowa State’s College of Agriculture and Life Sciences, and director of ISU Agriculture and Natural Resources Extension and Outreach.



John Lawrence, Iowa Nutrient Research Center, (515) 294-7801,

Brian Meyer, Agriculture and Life Sciences Communications, (515) 294-5616,