Agricultural transformations: climate change adaptation and farmer decision making
John C. Tyndall
Over the long-term, global climate change is projected to have negative impacts on agricultural productivity in the U.S. Corn Belt. Climate change will also exacerbate problems with soil loss through wind and water erosion in addition to environmental externalities associated with current land use practices, thus driving greater vulnerability of the Corn Belt agroecosystem. There is minimal research that examines how Corn Belt farmers will respond to climate change stressors and whether subsequent adaptive responses will alleviate or further exacerbate challenges in meeting production and conservation goals. This dissertation research explores farmer decision making in the context of climate change adaptation through the adoption and use of key management practices that can have soil and water conservation benefits. This research examines three distinct but connected studies that include qualitative, quantitative, and mixed methods analyses. Quantitative data include a survey of large-scale Corn Belt farmers (n=4,778) sampled from 22 six-digit Hydrologic Unit Code (HUC6) watersheds and secondary data from the 2012 Agricultural Census. Qualitative data were collected via in-depth interviews with 159 farmers across nine states in the Midwest (Iowa, Illinois, Indiana, Wisconsin, Minnesota, Michigan, Ohio, South Dakota, and Missouri).
Findings from the quantitative research suggest that farmers who believe they should adjust their practices to protect their farm from the negative impacts of increased weather variability are more likely to increase their use of no-till farming, cover crops, and tile drainage. Additionally, visiting with other farmers to observe their practices was positively associated with farmers increased use of the adaptive strategies examined. Famers with experience using no-till farming, cover crops, and tile drainage were also more likely to plan on increasing their use of these practices in response to climate changes. However, farmers who report high levels of confidence in their current practices are less likely to change their use of these practices in response to climate change.
Through examination of in-depth interviews, I found that farmers are engaging in greater soil stewardship as a way to mitigate weather related risks. Findings suggest that farmers’ shifting relationship to their soil resources may act as a kind of social-ecological feedback that enables farmers to implement adaptive strategies (e.g., no-till farming, cover crops) that build resilience in the face of increasingly variable and extreme weather. This was in contrast to emphasizing short-term tweaks to production (e.g., increased tillage in the spring) that may lead to greater vulnerability. Adoption of a soil stewardship ethic may also help farmers to resolve apparent tradeoffs between profitability in the short-term and field-level resilience over the long-term.
Finally, through a mixed methods analysis, I examined what influences farmers’ use of extended crop rotations, as a measure of cropping system diversity, particularly in the context of climate change adaptation. Findings suggest that path dependency on the intensive corn-based cropping system of the U.S. Corn Belt limits farmers’ ability to integrate more diverse crop rotations; yet, farmers in more diversified watersheds, those who farm marginal ground, and those with livestock are more likely to use extended rotations. Additionally, those farmers who currently use more diverse rotations are also more likely to see crop rotations as at risk mitigation tool in the context of climate change adaptation.
In total, this research offers a comprehensive analysis of farmer adaptive decision making through analysis of data on Corn Belt farmers’ conservation behaviors and climate change adaptation intentions, which is of unprecedented size and scope.