The Ohio State University
Co-Authors: Margaret Kalcic, Robyn Wilson, Douglas Jackson-Smith, and Jay Martin
Watershed modeling studies, including those of the Maumee River watershed, have found that targeting agricultural best management practices (BMPs) to fields with the highest nutrient loadings is more effective than randomly placing BMPs in reducing watershed-scale nutrient losses. However, farmers who manage these high nutrient-loss fields may not be the most willing to adopt BMPs. This study seeks to understand how targeting BMP placement by farmers’ willingness to engage in conservation practices, represented by a conservation identity proxy, affects nutrient loading from the Maumee River watershed as compared to the targeting of BMPs to fields with the highest nutrient loadings. To analyze the effect of targeting BMP placement by a farmer’s willingness to adopt a BMP, county-level distributions of farmer conservation identities, derived from farmer surveys completed in the watershed were embedded into a field-scale SWAT model of the Maumee River watershed. Results from this study indicate that targeting subsurface nutrient application and the adoption of buffer strips to fields with higher phosphorus losses lead to a faster reduction rate of phosphorus discharged from the watershed than by targeting these practices to fields managed by farmers with higher conservation identities. When targeting subsurface nutrient application and buffer strips to the 60% of fields with the highest rates of total phosphorus (TP) losses, spring TP losses decreased 27% and 17%, respectively, while spring Dissolved Reactive Phosphorus (DRP) losses decreased 35% and 12%, respectively. When targeting subsurface nutrient application and buffer strips to the 60% of fields managed by farmers with the highest conservation identities, spring TP losses decreased 19% and 10%, respectively, while spring DRP losses decreased 28% and 8%, respectively.
3 thoughts on “Integrating Agricultural Decision-Making Factors into Watershed Modeling of the Western Lake Erie Basin to Assess the Impact of Targeting BMP Placements”
Jeffrey, great work! Can you elaborate a little on what conservation identity, and what a proxy for it might be?
Thanks Ani! The conservation identity is just one of a variety of identities used in the literature to describe how farmers perceive themselves and in what makes a “good farmer.” For this research, it refers to how oriented farmers are towards adopting and applying conservation practices to their own operation. In the survey used in this work, conservation identity values were calculated for each respondent based off seven questions asking how important different factors were in a respondent’s definition of a good farmer. One example of these surveys questions is as follows: on a scale from “not important at all” to “very important” how does the following statement fit in your definition of a good farmer- “a good farmer is one who… considers the health of the waterways that run through or along their land to be their responsibility.” Individual responses to each of these seven questions could be used as a proxy for a farmer’s conservation identity. However, in the way I am using conservation identity, it itself is a proxy for the likelihood of future conservation practice adoption. We know through the literature that many factors can influence the decision-making process of farmers including demographic and psychological factors. Part of my future work will be linking more of these factors (i.e., age, efficacy of practice on reducing nutrient losses) into our watershed model, but it does seem that the conservation identity metric is generally a significant, positive factor in the decision-making process for conservation practice adoption. While, these other characteristics have positive, negative, or no effect on decisions related to conservation practice adoption, which makes modeling the future adoption of conservation practices a bit more complicated and nuanced.
Thanks Jeffrey – that’s very interesting. Good luck, this is much needed work!