A panel study of farmer nutrient management decisions in the Western Lake Erie Basin

The Maumee River watershed encompasses much of northwest Ohio and parts of Indiana and Michigan, adjacent to the western side of Lake Erie. The majority of the watershed is agricultural land, and since the 1960s and 70s,... [ view full abstract ]

The Maumee River watershed encompasses much of northwest Ohio and parts of Indiana and Michigan, adjacent to the western side of Lake Erie. The majority of the watershed is agricultural land, and since the 1960s and 70s, harmful algal blooms (HABs) have periodically appeared in the warmer and shallower western basin of the Lake near the Maumee River’s entry point. In recent years, the HABs have increased in scale dramatically, resulting in large-scale dead zones in the Lake that negatively impact wildlife, recreation, and the local drinking water supply. A major cause of the HABs is non-point source nutrient runoff from agricultural fields, namely dissolved reactive phosphorus. The 4Rs of Nutrient Stewardship were developed as a campaign and certification program to encourage and teach farmers to apply fertilizer at the right time, place, rate, and from an appropriate source to minimize nutrient runoff into waterways. We conducted a panel study of farmers in the Western Lake Erie Basin (WLEB) to understand their level of familiarity with the 4Rs, their perceptions of the effectiveness of the four practices, and the extent to which they have adopted the practices in recent years. We collected data at two points, early 2016 and 2018, to determine the behavioral impact of 4R educational efforts on the knowledge, beliefs, and management practices of crop growers in the WLEB. We were particularly interested in assessing any change in adoption over time, and the extent to which that change is a function of increased efficacy. We conducted a panel regression analysis to understand the relationship between different demographic and on-farm characteristics and the longitudinal adoption rates of 4R practices. From these results, we hope to understand how farmer’s perceptions of the 4Rs have evolved in recent years, what behaviors have greater adoption levels and potential, and what factors influence farmer decision-making related to on-farm nutrient management decisions. The results will determine if changes are needed to the 4R campaign by highlighting farmer motivations and potential constraints related to nutrient management decisions.