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The future of humanity depends on successfully adapting key cropping systems for food security, such as corn (Zea mays L.), to global climatic changes, including changing air temperatures. We monitored the effects of climate change on harvested yields using long-term research plots that were established in 2001 near Fort Collins, Colorado, and long-term average yields in the region (county). We found that the average temperature for the growing period of the irrigated corn (May to September) has increased at a rate of 0.023 °C yr−1, going from 16.5 °C in 1900 to 19.2 °C in 2019 (p < 0.001), but precipitation did not change (p = 0.897). Average minimum (p < 0.001) temperatures were positive predictors of yields. This response to temperature depended on N fertilizer rates, with the greatest response at intermediate fertilizer rates. Maximum (p < 0.05) temperatures and growing degree days (GDD; p < 0.01) were also positive predictors of yields. We propose that the yield increases with higher temperatures observed here are likely only applicable to irrigated corn and that irrigation is a good climate change mitigation and adaptation practice. However, since pan evaporation significantly increased from 1949 to 2019 (p < 0.001), the region’s dryland corn yields are expected to decrease in the future from heat and water stress associated with increasing temperatures and no increases in precipitation. This study shows that increases in GDD and the minimum temperatures that are contributing to a changing climate in the area are important parameters that are contributing to higher yields in irrigated systems in this region.

By tonnage, corn (Zea mays L.) is the #1 crop produced globally, and recent research has suggested that no-till (NT) systems can lead to reduced yields of this important crop. Additionally, there is a lack of long-term data about the effects of tillage and N management on cropping systems. Corn is the most nitrogen (N)-fertilized crop in the USA, and N losses to the environment contribute to significant impacts on air and water quality. We conducted long-term studies on conventional tillage (CT) and conservation tillage systems, such as strip tillage (ST) and NT, under different N rates. We found that immediately after conversion to NT, yields from NT were significantly lower than yields from CT (p < 0.1), but after five years of NT, the NT yields were 1.5% higher than the CT yields (p < 0.1). Initially, the NT yields were lower than the ST (p < 0.01), but after seven years of NT, the NT yields were comparable to ST grain yields. Although the total aboveground N uptake with NT immediately after conversion to NT was lower than with CT and ST, these differences were not significant in the long run. The nitrogen use efficiency (NUE) with NT increased over time. The present work highlights the importance of long-term research for determining the cumulative impacts of best management practices such as NT. We found that NT becomes a more viable practice after five or seven years of implementation, demonstrating the high importance of long-term research.

The commodity chocolate industry has been long recognized for unsustainable and unethical production practices. In contrast, the craft chocolate industry is well-positioned to move the chocolate industry in the direction of more ethical sourcing strategies, improved environmentally-conscious production practices, and higher quality products as a whole. Craft chocolate businesses also often adhere to ethical and economical guidelines, providing farmers with significantly higher farm gate prices and more resources than their commodity counterparts. However, poor standardization and understanding of industry needs raises questions regarding the integrity and longevity of this industry. With a survey of craft chocolate makers from around the world and an assessment of craft chocolate bar origins and makers, our data confirms for the first time that many craft chocolate producers prioritize responsible business practices including ethical sourcing (29%) and use of direct trade to source higher quality ingredients (38%). Of those surveyed, 60% of chocolate makers believe that routinely used quality assessment techniques do not meet the needs of craft chocolate makers or could use improvement. In addition, this research found that over 65% of craft chocolate makers primarily source beans from South and Central America (in direct contrast to commodity cacao systems, predominantly sourcing from West Africa). Furthermore, this research identifies gaps to support craft chocolate industry cohesion. The craft chocolate industry recognizes the importance of sustainable development and promotion of farmer welfare and environmental conservation and is a remarkably distinct entity within the chocolate world.