Evaluating the 4R Nutrient Stewardship Concept and Certification Program in the Western Lake Erie Basin

Since the mid 1990s, soluble P entering Lake Erie has shown an increasing trend, as have the frequency and severity of nuisance and harmful algal blooms. Evidence indicates that a considerable proportion of this soluble P comes from cropland. The 4R principles of nutrient stewardship have been promoted in the western Lake Erie basin (WLEB) and adoption is “catching on.” This multi-disciplinary research project, initiated in July 2014, aims to understand and quantify the water quality benefits of the 4R program.

Three WLEB sites are being instrumented for combined surface and subsurface edge-of-field monitoring from paired fields where management practices can be compared. A recent observation, from a paired site near the WLEB, showed a five-fold reduction in dissolved P loss in tile drain discharge resulting from incorporation of P fertilizer that was surface applied in early May. Available data from the Heidelberg University tributary program will be analyzed using a regression approach to assess impact of watershed practices. SWAT models for the Maumee, Sandusky, and Cedar-Portage watersheds are being set up to assess the watershed-scale impacts of 4R adoption. The Western Lake Erie Ecosystem Model was populated to evaluate the impact of proposed 4R activities in the Maumee watershed on 2011-14 Microcystis blooms.

Funding from the Mosaic Foundation and The Nature Conservancy is being leveraged for a triple bottom line assessment of the 4R program. To date, two undergraduate research assistants have been hired to develop timelines and summaries of key activities and to begin organizing data from a 2014 survey of Maumee farmers concerning cultivation and tillage practices conducted as part of an Ohio State University NSF project. Working with the Ohio Agri-Business Association, a survey of nutrient service providers participating in the 4R certification program has been developed. The project also helped survey, after a highly publicized drinking water advisory, Ohio residents’ willingness to pay to reduce harmful algal blooms in Lake Erie.

The outreach component of the project has been accomplished through popular press and news releases and two websites (http://4rcertified.org/research/ and http://research.ipni.net/project/IPNI-2014-USA-4RN09) In addition, the 4R research project has been referenced and discussed in at least a dozen recent meetings and workshops.

Over the coming five years, it is anticipated that this project will lead producers to better understanding and adoption of practices that support their crop productivity goals while reducing loss of dissolved P, and enable the industry to communicate quantified benefits to those concerned about Lake Erie water quality.