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Increasing soil organic carbon (SOC) stocks is increasingly targeted as a key strategy in climate change mitigation and improved ecosystem resiliency. Agricultural land, a dominant global land use, provides substantial challenges and opportunities for global carbon sequestration. Despite this, global estimates of soil carbon sequestration potential often exclude agricultural land and estimates are coarse for regions in the Global South. To address these discrepancies and improve estimates, we develop a hybrid, data-augmented database approach to better estimate the magnitude of SOC sequestration potential of agricultural soils. With high-resolution (30 m) soil maps of Africa developed by the International Soils Database (iSDA) and Malawi as a case study, we create a national adjustment using site-specific soil data retrieved from 1160 agricultural fields. We use a benchmark approach to estimate the amount of SOC Malawian agricultural soils can sequester, accounting for edaphic and climatic conditions, and calculate the resulting carbon gap. Field measurements of SOC stocks and sequestration potentials were consistently larger than iSDA predictions, with an average carbon gap of 4.42 ± 0.23 Mg C ha

Societal Impact Statement Plant breeding is crucial for improving agricultural crops for human use. However, an urgent rethink is needed to ensure the next generation of plant breeders have the necessary breadth of skills to provide ever more efficient, nutritious, profitable, and environmentally sustainable crops. Plant breeding is a multifaceted endeavor, which intersects with many other disciplines and professions. To help ensure that future plant breeding efforts are sustainable and relevant to the needs of society, it is vital that the interdisciplinary nature of the plant breeding profession is adequately reflected in student training and development. Summary Breeders need to have many faces to understand not only genetics but also environmental, social, and economic factors that are relevant for maintaining or improving crops for human use. In the United States, there is a long history of public involvement in agriculture and plant breeding. However, recent changes in the social systems underpinning public agriculture (i.e., funding structure) necessitate a rethinking of how agriculture education, specifically plant breeding education, should be facilitated. To provide viable plant breeding programs, it is necessary to explicitly acknowledge that breeding has been an interdisciplinary, long‐standing public endeavor to increase food system stability. Acknowledging this complexity has important pedagogical implications: the core of plant breeding resides in genetics, but the changing nature of this profession requires breeders to embrace a much broader training. Here, we suggest specific curricular objectives for plant breeders.

Cover cropping is considered a cornerstone practice in sustainable agriculture; however, little attention has been paid to the cover crop production supply chain. In this Perspective, we estimate land use requirements to supply the United States maize production area with cover crop seed, finding that across 18 cover crops, on average 3.8% (median 2.0%) of current production area would be required, with the popular cover crops rye and hairy vetch requiring as much as 4.5% and 11.9%, respectively. The latter land requirement is comparable to the annual amount of maize grain lost to disease in the U.S. We highlight avenues for reducing these high land use costs., In this Perspective, Bryan Runck and colleagues discuss an often-overlooked consequence of scaling up cover cropping – a cornerstone of sustainable agriculture. Using published seed yield data from common cover crops, they demonstrate the potentially large land use cost and discuss ways for reducing this cost.

Meeting the societal demand for food, bioproducts and water under climate change is likely to greatly challenge the maize-soybean agriculture of the Midwest USA, which is a globally significant resource. New agricultural systems are needed that can meet this challenge. Innovations in water management engineering and cropping system diversification may provide a way forward, enabling transformation to highly multifunctional agricultural watersheds that expand both agricultural production and water-related services to society, and which provide scalable units of climate adaptation in agriculture and water systems. Implementation and refinement of such watersheds require corresponding social innovation to create supportive social systems, in economic, political and cultural terms. A range of emerging social innovations can drive the emergence of highly multifunctional agricultural watersheds, by enabling robust cooperation, resource exchange and coordinated innovation across multiple societal sectors and scales. We highlight relevant innovations and opportunities for their exploratory implementation and refinement in the Midwest.

Emerging biotechnologies, such as genome editing, may revolutionize agricultural development through rapid and precise genetic manipulation of a wide range of crop traits without having to transfer foreign DNA [1]. If so, these new genetic‐engineering (GE) technologies can help to generate crop varieties to address critical challenges in agricultural development, such as climate resilience or nutrient uptake, or diet‐related problems in nutrition and health in poorer countries. However, society must also be protected from potential harmful effects of genetically manipulated crops on the environment, human health, or social welfare. Governance of these crops must therefore balance agricultural developments with risk assessment and prevention of potential harm. > …genome editing is being used to improve the characteristics of major crop plants, but the governance of crop genome editing is poorly defined and developed Presently, genome editing is being used to improve the characteristics of major crop plants, but the governance of crop genome editing is poorly defined and developed. Influential groups concerned with the potential hazards of such crops view this situation with growing alarm, which has created tensions with the academic community and regulatory agencies [2]. Both the USA and the European Commission are currently reviewing the governance of crops produced by genome editing and other new technologies. On the US side, at least, the review process appears unlikely to result in governance approaches that will satisfy parties that are concerned with either over‐ or under‐regulation of such crops, and tension and conflicts about them are likely to heighten. We propose an alternative approach for governance of these crops that may help to defuse tensions and enable exploration of genome editing technologies’ potential while protecting society from harm: a cooperative governance network. Such networks have performed well in …

Agent based modeling (ABM) is a standard tool that is useful across many disciplines. Despite widespread and mounting interest in ABM, even broader adoption has been hindered by a set of methodological challenges that run from issues around basic tools to the need for a more complete conceptual foundation for the approach. After several decades of progress, ABMs remain difficult to develop and use for many students, scholars, and policy makers. This difficulty holds especially true for models designed to represent spatial patterns and processes across a broad range of human, natural, and human-environment systems. In this paper, we describe the methodological challenges facing further development and use of spatial ABM (SABM) and suggest some potential solutions from multiple disciplines. We first define SABM to narrow our object of inquiry, and then explore how spatiality is a source of both advantages and challenges. We examine how time interacts with space in models and delve into issues of model development in general and modeling frameworks and tools specifically. We draw on lessons and insights from fields with a history of ABM contributions, including economics, ecology, geography, ecology, anthropology, and spatial science with the goal of identifying promising ways forward for this powerful means of modeling.

This paper illustrates the application of Geodesign in the context of multifunctional landscape scale planning and design to optimize production of food and biofuel commodities with enhanced water quality and habitat performance. It draws on multiple disciplinary perspectives, highlighting the contributions of Geodesign in advancing stakeholder consensus in balancing natural resource protection and agricultural production priorities. The paper uses the Seven Mile Creek Fuelshed Project as a research context for examining the ways that Geodesign can enhance collaborative planning processes, build knowledge of natural and production systems at the landscape scale, and integrate consideration of feedback from multiple performance criteria into an adaptive and iterative process of landscape planning and design. The paper describes the development and application of the Geodesign system used in the landscape planning process and offers important insights into how the system contributed to the collaborative stakeholder engagement, informed stakeholder decision making, and enhanced the landscape planning outcomes. A mixed-method analytical approach is used to assess stakeholder perceptions and the outcomes of the collaborative Geodesign process.

Historically, agroecosystems have been designed to produce food. Modern societies now demand more from food systems—not only food, fuel, and fiber, but also a variety of ecosystem services. And although today's farming practices are producing unprecedented yields, they are also contributing to ecosystem problems such as soil erosion, greenhouse gas emissions, and water pollution. This review highlights the potential benefits of perennial grains and oilseeds and discusses recent progress in their development. Because of perennials' extended growing season and deep root systems, they may require less fertilizer, help prevent runoff, and be more drought tolerant than annuals. Their production is expected to reduce tillage, which could positively affect biodiversity. End-use possibilities involve food, feed, fuel, and nonfood bioproducts. Fostering multidisciplinary collaborations will be essential for the successful integration of perennials into commercial cropping and food-processing systems.

Since the mid-20th century, crop breeding has driven unprecedented yield gains. Breeders generally select for broadly- and reliably-performing varieties that display little genotype-by-environment interaction (GxE). In contrast, ecological theory predicts that across environments that vary spatially or temporally, the most productive population will be a mixture of narrowly adapted specialists. We quantified patterns of broad and narrow adaptation in modern, commercial maize (Zea mays L.) hybrids planted across 216 site-years, from 1999-2018, for the University of Illinois yield trials. We found that location was the dominant source of yield variation (44.5%), and yearly weather was the smallest (1.7%), which suggested a benefit for reliable performance in narrow biophysical environments. Varieties displayed a large "home field advantage" when growing in the location of best performance relative to other varieties. Home field advantage accounted for 19% of GxE and provided a yield increase of 1.01 ± 0.04 Mg ∙ ha-1 (7.6% relative to mean yield), yet was both smaller than predicted by a null model and unchanged across time. This counterfactual suggests that commercial breeding programs have missed an opportunity to further increase yields by leveraging local adaptation. Public breeding programs may pursue this opportunity by releasing specialist varieties that perform reliably in narrow environments. As seed sources are increasingly privatized and consolidated, this alternate strategy may compliment private breeding to support global food security.

Climate change is expected to severely impact farming in sub-Saharan Africa. Now research shows that crop wild relatives might be able to secure Africa’s existing cropping practices by providing the genetic diversity needed to adapt crops to climates that they have never seen before.

Given that much of the learning about international agroecology would ideally occur outside the classroom, adventure learning (AL) and systems action education (SAE) can offer synergistic approaches that synthesize these methodologies into a cohesive student learning experience. This article reports on the evolution of a series of international agroecology courses offered from 2009 to 2011 that progressively integrated AL and SAE approaches in course design. The courses were taught by a University of Minnesota professor as he bicycled across Africa (2009 and 2010) and South America (2011), exploring various landscapes, crops, climatic regions, and food systems with students back home via distance technologies. End-of-course survey responses indicated that students (1) did not find the course any more rigorous than similar level courses, (2) found the course much more unique (p < 0.01), and (3) increased their desire to travel abroad (p < 0.01). Our examination also revealed challenges and opportunities inherent with AL and SAE–merged classrooms. Overall, we found that AL and SAE approaches could be integrated to enhance agroecology education and can make courses inspiring, challenging, and rewarding. The result could have implications for schools that seek to prepare students to work in a global environment.

To further synthesize Systems Action Education (SAE) and adventure learning (AL), a new education framework is presented called the Extended Classroom Framework (ECF) for teaching systems analysis of food systems. Extended Classroom Framework integrates SAE and AL with the circulatory system of science to describe how the classroom interacts with society. In the fall of 2012, the ECF was utilized to design a hybrid course at the undergraduate level that explored four different international agroecoregions through the perspective of on-the-ground collaborators. By utilizing online geographic information systems and an online social network, students digitally explored these agroecosystems as open-ended cases. A pre- and post-test of the Intercultural Development Inventory was given to the students. Students also wrote four reflective journals that were coded and thematically analyzed. Six of seven of students showed positive shifts in their developmental orientation (p < 0.05). Four of seven students showed decreases in their intercultural orientation gap. Every student ended the course similarly or less culturally disengaged to a primary cultural group, with six students in the resolved category compared with four at the beginning of the course. Student reflective journals illustrated growth in considering agroecosystems contextually and as coupled human–environmental systems. These results show that the ECF offers a viable framework for developing student capacities to engage “wicked” problems. Impact Statement The Extended Classroom Framework (ECF) provides a means to synthesize online GIS and social networks to allow students and instructors to experientially learn about human–environment interactions in multiple international contexts in a cost-effective manner. By providing preliminary evidence documenting the framework in action, this article shows the ECFs potential to increase students’ ability to think systemically and work across differences, essential skill sets for practitioners working within “wicked problems.”

Over the last half-century, crop breeding and agro- nomic advances have dramatically enhanced yields in temperate summer-annual cropping systems. Now, diversification of these cropping systems is emerging as a strategy for sustainable intensifica - tion, potentially increasing both crop production and resource conservation. In temperate zones, diversification is largely based on the introduc - tion of winter-annual and perennial crops at spatial and temporal locations in annual-crop production systems that efficiently increase production and resource conservation. Germplasm development will be critical to this strategy, but we contend that to be feasible and efficient, germplasm improve - ment must be closely integrated with commercial- ization of these crops. To accomplish this integra- tion, we propose a novel approach to germplasm development: the reflective plant breeding para - digm (RPBP). Our approach is enabled by develop- ments in genomics, agroecosystem management, and innovation theory and practice. These develop- ments and new plant-breeding technologies (e.g., low-cost sequencing, phenotyping, and spatial modeling of agroecosystems) now enable germ- plasm development to proceed on a time scale that enables close coordination of breeding and com- mercialization (i.e, development of cost-effective production systems and supply-value chains for end-use markets). The RPBP approach is based on close coordination of germplasm development with enterprise development. In addition to supporting strategic diversification of current annual-cropping systems, the RPBP may be useful in rapid adap- tation of agriculture to climate change. Finally, the RPBP may offer a novel and distinctive pathway for future development of the public plant-breeding programs of land-grant universities with implica- tions for graduate education for public- and private- sector plant breeders.

Efficiently allocating nitrogen (N) across space maximizes crop productivity for a given amount of N input and reduces N losses to the environment. Here we quantify changes in the global spatial efficiency of cropland N use by calculating historical trade-off frontiers relating N inputs to possible N yield assuming efficient allocation. Time series cropland N budgets from 1961 to 2009 characterize the evolution of N input-yield response functions across 12 regions and are the basis for constructing trade-off frontiers. Improvements in agronomic technology have substantially increased cropping system yield potentials and expanded N-driven crop production possibilities. However, we find that these gains are compromised by the declining spatial efficiency of N use across regions. Since the start of the Green Revolution, N inputs and yields have moved farther from the optimal frontier over time; in recent years (1994–2009), global N surplus has grown to a value that is 69% greater than what is possible with efficient N allocation between regions. To reflect regional pollution and agricultural development goals, we construct scenarios that restrict reallocation, finding that these changes only slightly decrease potential gains in nitrogen use efficiency. Our results are inherently conservative due to the regional unit of analysis, meaning a larger potential exists than is quantified here for cross-scale policies to promote spatially efficient N use.

Diversification of agroecological systems to enhance agrobiodiversity is likely to be critical to advancing environmental, economic, and social sustainability of agriculture. Temperate-zone agroecological systems that are currently organized for production of summer-annual crops can be diversified by integration of fallow-season and perennial crops. Integration of such crops can improve sustainability of these agroecological systems, with minimal interference with current agricultural production. Importantly, these crops can provide feedstocks for a wide range of new bio-products that are forming a new agricultural bioeconomy, potentially providing greatly increased economic incentives for diversification. However, while there are many fallow-season and perennial crops that might be used in such a “bioeconomic” strategy for diversification, most are not yet well adapted and highly-marketable. Efforts are underway to enhance adaptation and marketability of many such crops. Critically, these efforts require a strategic approach that addresses the inherent complexity of these projects. We outline a suitable approach, which we term “sustainable commercialization”: a coordinated innovation process that integrates a new crop into the agriculture of a region, while intentionally addressing economic, environmental and social sustainability challenges via multi-stakeholder governance. This approach centers on a concerted effort to coordinate and govern innovation in three critical areas: germplasm development, multifunctional agroecosystem design and management, and development of end uses, supply chains, and markets. To exemplify the approach, we describe an ongoing effort to commercialize a new fallow-season crop, field pennycress (Thlaspi arvense L.).