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  1. Abstract

    Food security and the agricultural economy are both dependent on the temporal stability of crop yields. To this end, increasing crop diversity has been suggested as a means to stabilize agricultural yields amidst an ongoing decrease in cropping system diversity across the world. Although diversity confers stability in many natural ecosystems, in agricultural systems the relationship between crop diversity and yield stability is not yet well resolved across spatial scales. Here, we leveraged crop area, production, and price data from 1981 to 2020 to assess the relationship between crop diversity and the stability of both economic and caloric yields at the state level within the USA. We found that, after controlling for climatic instability and differences in irrigated area, crop diversity was positively associated with economic yield stability but negatively associated with caloric yield stability. Further, we found that crops with a propensity for increasing economic yield stability but reducing caloric yield stability were often found in the most diverse states. We propose that price responses to changes in production for high-value crops underly the positive relationship between diversity and economic yield stability. In contrast, spatial concentration of calorie-dense crops in low-diversity states contributes to the negative relationship between diversity and caloric yield stability. Our results suggest that the relationship between crop diversity and yield stability is not universal, but instead dependent on the spatial scale in question and the stability metric of interest.

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  2. Abstract

    Wildfire smoke is frequently present over the U.S. during the agricultural growing season and will likely increase with climate change. Studies of smoke impacts have largely focused on air quality and human health; however, understanding smoke's impact on photosynthetically active radiation (PAR) is essential for predicting how smoke affects plant growth. We compare surface shortwave irradiance and diffuse fraction (DF) on smoke‐impacted and smoke‐free days from 2006 to 2020 using data from multifilter rotating shadowband radiometers at 10 U.S. Department of Agriculture UV‐B Monitoring and Research Program stations and smoke plume locations from operational satellite products. On average, 20% of growing season days are smoke‐impacted, but smoke prevalence increases over time (r = 0.60,p < 0.05). Smoke presence peaks in the mid to late growing season (i.e., July, August), particularly over the northern Rocky Mountains, Great Plains, and Midwest. We find an increase in the distribution of PAR DF on smoke‐impacted days, with larger increases at lower cloud fractions. On clear‐sky days, daily average PAR DF increases by 10 percentage points when smoke is present. Spectral analysis of clear‐sky days shows smoke increases DF (average: +45%) and decreases total irradiance (average: −6%) across all six wavelengths measured from 368 to 870 nm. Optical depth measurements from ground and satellite observations both indicate that spectral DF increases and total spectral irradiance decreases with increasing smoke plume optical depth. Our analysis provides a foundation for understanding smoke's impact on PAR, which carries implications for agricultural crop productivity under a changing climate.

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  3. Under the best of circumstances, learning to conduct qualitative research is challenging, both intellectually and emotionally. Engaging in such learning in difficult situations, such as a global pandemic, may heighten challenges while creating opportunities for truly deep learning. The purpose of this paper is to provide methodological insights to guide the growth of new qualitative researchers and inform the design of introductory methods courses based on the learning experiences of a group of graduate students conducting their first qualitative research projects. We present students’ experiences with choosing and planning a project, navigating relationships with study participants, and conducting observations and interviews. Explicit connections to qualitative methodology are offered for every stage of student research engagement. An analysis of the student authors’ experiences highlights the associated learning and innovation necessary to adapt to adversity when conducting qualitative research. Advancements in research reciprocity and human connection are presented, as experienced by the student authors. We conclude with implications and insights for teaching and learning qualitative research and ethical considerations that transcend pandemic circumstances. It is the intent of this manuscript to support the development of deep reflexive practice for new qualitative researchers, effective instructional approaches for those who teach research methods, and an insight into the power of diverse student researchers learning new skills together for the global research community. 
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    Free, publicly-accessible full text available December 1, 2024
  4. Free, publicly-accessible full text available August 1, 2024
  5. Purpose The purpose of this paper is to recommend behavioral targets for future interventions to reduce greenhouse gas emissions at college campuses and to advise interventionists on how to choose between many potential behavioral targets. Design/methodology/approach The authors used the community-based social marketing (CBSM) methodology over two studies. In Study 1, the authors assessed adoption rates (i.e. penetration) and likelihood of adoption (i.e. probability) for 16 potential behavioral targets. In Study 2, the authors used quantitative and qualitative methods to assess the barriers and benefits of engagement in five of the top-performing behaviors from Study 1. Findings The findings suggest that an intervention to promote purchasing green energy credits (GECs) has a high potential to reduce emissions. Purchasing GECs has a small penetration (<7%) and a large impact (1,405 kgCO 2 e/person/year). Compared to the other four behaviors the authors examined in Study 2, purchasing GECs is also more convenient and requires very little time. Thus, the behavior should be appealing to many individuals interested in reducing emissions or protecting the environment. Originality/value The authors performed a holistic evaluation of potential behavioral targets that included a barrier and benefit analysis, in addition to the traditional CBSM method of combining impact, probability and penetration. 
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    Free, publicly-accessible full text available May 19, 2024
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