Iowa Nutrient Research Center announces funding for new water quality projects

The Iowa Nutrient Research Center at Iowa State University announces funding of over $1.4 million to support a dozen water quality and nutrient management projects for 2022-2023.

“This year, INRC celebrates its first decade. We are very pleased to have the opportunity to continue supporting this important work to improve Iowa’s water quality and agricultural systems,” said Matt Helmers, Iowa Nutrient Research Center director and professor of agricultural and biosystems engineering at Iowa State. “These projects represent new approaches, as well as continuing study of areas where more work is needed to inform recommendations for farmers, policymakers and stakeholders.” The new projects, listed below, fall into INRC’s edge-of-field, multi-objective and nutrient management categories. Lead researchers are located at Iowa State unless otherwise indicated. Projects will extend for one to two years.

Edge of Field
• Extending Saturated Buffers to Additional Landscape Positions. Led by Tom Isenhart, professor, natural resource ecology and management, this project seeks to extend the new saturated buffer practice to additional landscape positions in combination with existing grass waterways and prairie strips, which could dramatically increase the practice’s potential for nitrate removal.
• Unlocking the bioreactor microbiome for nutrient management and water quality. Led by Adina Howe, associate professor, agricultural and biosystems engineering, this project seeks to identify and manipulate microbial communities in corncob and woodchip bioreactors that mediate complete denitrification of nitrate to dinitrogen gas. The investigation aims to reduce potential for undesirable emissions and expand the utility of this conservation practice.
• Evaluating the effectiveness of stacked practices: Utilizing modified blind inlets at terrace sites for N and P load reductions. Led by Matthew Streeter, assistant research scientist, IIHR Hydroscience and Engineering at the University of Iowa, this project builds on a previous pilot study to investigate nutrient load reductions at blind inlet locations and compare the effectiveness of blind inlets alone and in combination with other edge-of-field practices. A goal is to evaluate the potential of a new conservation practice that would reduce both N and P export from agricultural fields.      

• Evaluating the relation of phosphorus to turbidity during high flow events in western Iowa rivers to improve phosphorus load estimates. Led by Keith Schilling, director of the Iowa Geological Survey at the University of Iowa, the project will gather new data supporting improvement of models that predict particulate phosphorus concentrations, focusing on locations on western Iowa rivers where historical data has been lacking.
• Landowners Matter Too: Accelerating Adoption of In-field and Edge-of-field Nutrient Reduction Practices through Better Engaged Landowners. Led by Chad Hart, professor, economics, the project will assess Iowa landowners’ views on and barriers to adopting key in-field and edge-of-field practices for nutrient reduction, looking for more “win-win” situations that could encourage increased conservation practice adoption.
• Sociological water quality research: quantifying factors at multiple scales that influence farmers to shift from being potential to actual adopters of conservation practices. Led by Suraj Upadhaya, postdoctoral researcher, natural resource ecology and management, the project will seek to better understand influences that lead farmers to shift from potential to actual adopters of conservation practices.
• Spatially delineated carbon credit potential and implied nutrient reduction co-benefit: An assessment with integrated ecological and economic modeling framework. Led by Hongli Feng, assistant professor, economics, the project will take a cross-disciplinary approach to investigate the nutrient reduction potential of various carbon initiatives with integrated modeling that incorporates diverse variables, including information on farmers’ response to different incentive payment strategies.
• Quantifying co-benefits of water quality conservation practices for wildlife of greatest conservation need in Iowa. Led by Adam Janke, associate professor, natural resource ecology and management, the project seeks to advance collaboration between stakeholders interested in water quality and wildlife conservation in working landscapes using modeling to identify impacts of watershed conservation practice implementation on wildlife species of greatest conservation need.
• IIHR Hydroscience and Engineering Work plan (2022-2023). Led by Chris Jones, research scientist, IIHR-Hydroscience and Engineering at the University of Iowa, this project will continue to develop and aggregate data to be used by INRC and others to support enhanced nutrient management.

Nutrient Management
• Assessing the effectiveness of spatial and temporal separation of a cereal rye cover crop from corn on nutrient reduction and corn yield. Led by Alison Robertson, professor, plant pathology and microbiology, this project will build on past research to improve understanding of how spatial and temporal management of cereal rye affects corn development and yield, seedling disease, nutrient recycling, soil erosion and water infiltration.
• Benefits of winter cereal rye cultivar selection in mitigating corn yield drag. Led by Alison Robertson, professor, plant pathology and microbiology, this project will advance understanding of how different cereal rye cultivars impact corn production to improve recommendations for its use as a cover crop in corn-soybean production systems.  
• Spatial models for scaling optimal nutrient management research from plot to field and watershed scales. Led by Bradley Miller, associate professor, agronomy, the project will study the interaction of management practices with different soil environments to develop models capable of predicting soil nutrient outcomes from field-to-watershed scales.

This is Iowa Nutrient Research Center’s 10th year funding water quality research since it was created by the Iowa Legislature in 2013. The new grants bring the total number of projects funded fully or partially by the center’s competitive award process to 127, representing a total of approximately $15 million invested in nutrient-related water quality research.

Each year, a committee of investigators in Iowa and surrounding states, without ties to the proposals, assist INRC in evaluating proposals to select the most promising projects. Find more detail about these and past projects online at

A fall 2022 - spring 2023 seminar series, “Highlights from a decade of research and impacts,” is highlighting past INRC-funded projects. The hybrid sessions, which are free and open to the public, are being held the second Wednesday of the month, from 3:10-4:00 p.m. on the Iowa State campus and online. Find more details at:

The Iowa Nutrient Research Center at Iowa State University pursues science-based approaches to evaluating the performance of current and emerging nutrient management practices, providing recommendations on implementing the practices and developing new practices.