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Frontier: Beyond Productivity—Recreating the Circles of Life to Deliver Multiple Benefits with Circular Systems

Lois Wright Morton1,*, Ernie Shea2


Published in Journal of the ASABE 65(2): 411-418 (doi: 10.13031/ja.14904). Copyright 2022 American Society of Agricultural and Biological Engineers.


1 Department of Sociology and Criminal Justice, Iowa State University, Ames, Iowa, USA.

2 Solutions from the Land, Lutherville, Maryland, USA.

* Correspondence: lwmorton@iastate.edu

The authors have paid for open access for this article. This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License https://creative commons.org/licenses/by-nc-nd/4.0/

Submitted for review on 11 October 2021 as manuscript number NRES 14904; approved for publication as an Invited Frontier Article and as part of the Circular Food and Agricultural Systems Collection by Associate Editor Dr. Jonathan Watson and Community Editor Dr. Kati Migliaccio of the Natural Resources & Environmental Systems Community of ASABE on 17 February 2022.

Highlights

Abstract. Circularity in agriculture and food systems holds promise for recovering lost resources and addressing the unintended consequences of linear production. The challenge to agriculture is to adapt the circularity observed in complex natural ecosystems into practical applications for producers and their value chains, thereby shifting intensive linear systems away from the single goal of optimizing monoculture productivity toward circles of life capable of producing multiple benefits concurrently. Mixed multi-plant and animal agricultural systems that leverage integrated land management and biodiversity have potential to deliver multiple benefits, including increased productivity, pest and disease control, water quality, soil health, and economic profitability. Replacing linear “take, make, and dispose” systems with circular “make, use, recycle, and reuse” systems offers solutions for managing input costs and gaining income and ecosystem benefits from wastes that are otherwise lost and can harm agro-ecosystems. Technologies, innovations, and practices that reinforce and expand whole-system management, build on local conditions and knowledge, and that deliver multiple benefits beyond optimum production will be necessary for circular systems to emerge. This article provides several examples of current farm applications and experimentation with circular systems as practical solutions at different scales relevant to a range of production systems in developed, developing, and underdeveloped countries.

Keywords. Agriculture, Biodiversity, Circles of life, Circular systems, Complexity, Farmers, Food systems, Innovations, Linear treadmills of production, Mixing species, Multi-benefit production, Technologies.

The relationships among agricultural production, rural livelihoods and economic well-being, healthy ecosystems, and food security and nutrition are complex and not always apparent. Today’s farmers are confronted with problems that are interdependent. Their challenges are system problems: increasing variability in weather, not enough or too much soil moisture, insect pressure, waste management, water quality, soil fertility, back-orders on repair parts, and high crop yields at low market prices. Operational and longer-term strategic solutions require recognition that every system is connected to other systems, and effective management decisions must account for this complexity. When systems relationships are ignored, decisions that address the visible problem may create a myriad of unintended consequences and serious resource issues.

Meadows (2008) in Thinking in Systems explains that the multi-directional interconnections of complex systems produce their own patterns of behavior over time. Each system is driven by internal and outside forces, and the system’s response to these forces becomes a characteristic of the system itself (Meadows, 2008). For example, biodiversity in agricultural cropping systems promotes circularity within and among systems, creating complexity that can give the system unique capacities to provide multiple benefits, such as ecosystem services, as well as food products (Malezieux et al., 2009; Tamburini et al., 2020). In contrast, a simple optimization approach to managing agricultural efficiency results in simplifying the production structure to achieve the singular goal of increased monoculture productivity (Malezieux et al., 2009). The reduction in system complexity reduces the variety of services that the system can provide. Further, optimization assumes that an agricultural system can be held constant in an optimal state by various strategies to deliver maximum sustained benefit (Walker and Salt, 2006). This management model, based on achieving optimal production and assuming average conditions, overlooks how systems actually work and how they are continually reconfigured and change as they respond to extreme events (Walker and Salt, 2006; Malezieux et al., 2009). Optimization also does not account for the relationships among scales, sectors, and the interconnected human and natural ecosystems that are sources of change in managed agricultural systems. This narrow focus limits the capacity to rebalance these relationships to deliver the variety of essential benefits that farmers and society value.

There is increasing evidence that linear agriculture and food systems that proceed from pre-production to production, post-harvest processing, and consumption; that require land, water, energy, nutrients, labor, and capital as inputs; and that discard the waste byproducts produced in the process (Jones et al., 2021) do not support nor have capacity to promote healthy ecosystems, which are the foundation of sustainable production. The natural world is comprised of many circular systems that are continuously interacting and dynamically responding as conditions change (fig. 1). There is no waste in natural systems. One organism’s waste is another organism’s food, and nutrients and energy flow in loops of growth, decay, and reuse. Agriculture, forests, and wetlands, the Earth’s resources and atmosphere, and humans with their multiple cultures and values are complex, interwoven, and multi-dimensional systems that are layered onto each other, interacting spatially and continuously looping forward, backward, and sideways. The efficiency of natural systems suggests that similar circular systems for agriculture and food production may be more efficient than linear systems in delivering the multiple benefits that society needs.

Figure 1. Circles of life in the natural world include many dynamic interwoven processes over space and time.

In this article, we briefly explore how linear production systems that focus on productivity gains alone can create unsustainable resource utilization and trap farmers on a treadmill of increased productivity and decreasing profitability. We propose that circular systems that make, use, reuse, remake, and recycle resources can help farmers create circles of life that capture the lost resources and profitability embedded in byproducts and can lead to minimal waste. Central to the circles of life model are the realignment and broadening of farm goals to rebalance productivity and ecosystem services in ways that deliver multiple benefits to the farm and to society. Examples of multi-benefit circles of life as works in progress are described. Finally, increasing diversity and multi-species livestock and cropping systems using whole-system technologies, innovations, and agricultural research are recommended.

Increased Productivity, Decreased Profits, Unwanted Outputs, and Resource Losses

Critics of modern agriculture and food production have described it as a treadmill of technological progress that leads to increased productivity and increased earnings for early adopters. The treadmill analogy continues as mainstream farmers adopt new technologies; production and supply increase but prices decrease, as does profitability, leading to the need to further increase productivity with new technologies to ensure farm income (Schnaiberg, 1980; Rudel et al., 2011; Hansen, 2019). Basso et al. (2021) observed that the linear structure of current food and agricultural production systems, rather than technology or delayed adoption, has led to unintended outcomes such as diminished rural livelihoods, increased farm size and specialization, depletion and degradation of resources, and increased pressure on the environment. They explained that technological progress and increased productivity have been extraordinarily successful at delivering agricultural outputs, but current production is “highly dependent on external inputs (e.g., seeds, fertilizer, pesticides, energy)” and a linear path of “take-make-use-waste-pollute.”

This view of agricultural innovation as the driver of a never-ending treadmill assumes sustained productivity pressure, sustained price pressure from productivity increases, and that productivity has a maximum upper limit with water quality and nutrient availability as limiting factors (Hansen, 2019; Carolan, 2016; Stone and Flachs, 2018). It also assumes a linear model of agriculture that targets increased productivity and optimized profitability but overlooks the variety of technologies that can enable reuse and renewal of resources. Thus, it narrowly connects increased market competition with increased pressure on natural resources and their degradation. It does not account for the diversity and complexity of the resource base, nor the increased social value of nature-positive co-production of water, soil health, and other natural resources. Nor does it acknowledge that bioenergy and animal production are ever-increasing consumers of agricultural commodities (Carolan, 2016; Hansen, 2019; Rowntree et al., 2020) that can create new cycles of supply, consumption, and resupply.

More importantly, this critique of agricultural innovation does not offer an alternative structure capable of using new technologies and innovations to support complex relationships among managed agricultural systems and the Earth’s resources with potential co-benefits to production, profitability, and ecosystem services (Morton, 2020b). Enlarging agricultural and food system benefits beyond productivity to encompass the use of production byproducts, reintroduction of waste into productive use, and the incorporation of multiple ecosystem services beyond short-term profitability is a critical intervention for redirecting the linear treadmill into a multi-benefit structure. Effective circular systems have potential to keep resources and products in use, reduce waste and pollution, and regenerate and revalue natural resources to increase social and farmer value (Jones et al., 2021).

Transforming Linear Systems to Circles of Life

Limitations of water quality and quantity are the most visible evidence of shifting climates and increasing water demand from growing populations. Local and worldwide prolonged drought, reduced snowpack, flooding, soil erosion, shifts in river flows, as well as wildfires, are stressing human and natural systems. The rate of productivity gains is slowing and is projected to fall short of the anticipated global demand for food by the year 2050 (Jones et al., 2021). Although productivity per unit of land area has increased enormously over the past 100 years, there are absolute limits to the amounts of freshwater and arable land available (Engler, 2021). Increases in production must be accomplished with fewer resources and under conditions of declining biodiversity and increasing risks to ecosystem health. This means that we must better understand the relationships of human and natural systems and find ways to remain productive while using, protecting, and renewing our natural resources as we adapt to unexpected events such as disruptions to food security, broken supply chains, limited water resources, changing markets, and extreme weather events and climate shifts (Morton 2020b).

Farmers, ranchers, foresters, fishers, and their agricultural partners around the world are key components of human and natural systems and are essential to food security and human health. Their occupations involve working with nature, remaking nature to achieve human goals, and preparing for and responding to anticipated and unexpected events as they make a living for their families and try to meet societal expectations. Circular systems offer producers an opportunity to rethink and redesign their processes at many levels to better respond to a changing world. Circular systems invite a re-evaluation of how inputs and outputs are sourced, used, reused, and recycled, and how systems management can reduce waste, improve ecosystem integrity, and increase productivity and profitability. The challenge is how to transform the circularity observed in complex natural ecosystems into practical applications of value to farmers and their value chains.

In 2014, the U.S. Third National Climate Assessment defined adaptation as “actions to prepare for and adjust to new conditions, thereby reducing harm or taking advantage of new opportunities” (Melillo et al., 2014, p. 10). The Fourth National Climate Assessment expanded on that definition by adding that adaptation entails iterative risk management without an end point. Iterative risk management, e.g., anticipating and responding to climate change as an ongoing cycle of assessment, action, reassessment, learning, and response (Lempert et al., 2018), mimics the processes found in systems management and circular economies. Many farmers know that difficult challenges are ahead, and they recognize the urgency to adapt to the risks of changing conditions (SfL, 2013; Morton et al., 2021). They are eager to learn more about how to leverage whole-system relationships, and many are already embracing new strategies and technologies to find solutions.

Solutions from the Land (SfL), a not-for-profit organization led by farmers, ranchers, and foresters, is facilitating state, national, and global alliances to accelerate the exchange of knowledge and innovation and prepare farmers to better manage their systems to deliver near-term, cost-effective, integrated solutions for an uncertain and less predictable future. Solutions from the Land was conceived by a cross-sector team of respected agriculture, forestry, conservation, academic, and industry leaders, who came together in 2009, inspired by the clean energy discussions facilitated by the 25×’25 Alliance, to explore integrated land management solutions to help meet food security, economic development, climate change, and biodiversity goals. Beginning as a dialogue on what the future of agriculture might look like, and co-sponsored by the United Nations Foundation, The Nature Conservancy, Conservation International, and the Farm Foundation, SfL has evolved into a 501c3 non-profit focused on agricultural solutions to global challenges. Its mission is to identify and facilitate the implementation of policies, practices, and projects at a landscape scale that will result in sustainable land management to produce food, feed, fiber, and energy while protecting and improving critical environmental resources and delivering high-value solutions to combat climate change.

The need for innovative collaborative strategies that reinforce productivity and nature-positive systems and behaviors extends far beyond U.S. food systems to the global goals articulated by the United Nations in the 17 Sustainable Development Goals (SDGs) for 2030. Agriculture factors directly into at least ten of the SDGs, including Goal 1: No poverty (profitable livelihoods); Goal 2: Zero hunger (food production); Goal 3: Good health and well-being (nutrition); Goal 6: Clean water and sanitation (effective management of water); Goal 7: Affordable clean energy; Goal 8: Decent work and economic growth (promoting inclusive, sustainable economic growth and full and productive employment); Goal 12: Responsible consumption and production (managing waste); Goal 13: Climate action (adapting to and mitigating climate change); Goal 14: Life below water; and Goal 15: Life on land (biodiversity dependent on sustainably managing farms and landscapes) (Lal, 2020).

Solutions from the Land

How can current agriculture move more quickly toward circularity and achieve co-production of food and ecosystem services that are of value to the Earth and human society? The farmer leaders of SfL are reaching out to their farmer peers, talking about the challenges that agriculture faces, and exploring how increased diversity, whole-farm systems, and circular economies can offer solutions. Farmers and researchers are already experimenting with mixed multi-plant and animal systems that leverage biodiversity to increase productivity, control pests and disease, enhance ecological services, and ensure economic profitability (Malezieux et al., 2009; Tittonell, 2014; Tamburini et al., 2020; Rowntree et al., 2020). Of great interest is how circular systems might offer transitional paths within food and agriculture value chains by (1) designing out waste and pollution (recovering and reintroducing discarded wastes for productive uses); (2) protecting and renewing natural systems; (3) establishing processes that systematically reuse products and materials; and (4) offering economic benefits from reduced inputs and value-added byproducts (Jones et al., 2021).

Figure 2. Whole-systems strategies to enable agriculture and food systems to deliver multiple benefits (Morton et al., 2021) based on the Sustainable Development Goals (SDGs) of the United Nations (UN, 2021).

The SfL farmer leaders have a vision that innovative farmers, ranchers, and foresters can help their peers construct sustainable, profitable, and resilient systems as the foundation for their own livelihoods and for a world of abundance on many scales. These farmers are confident that they are capable of co-producing nutritious food, feed, fiber, clean energy, healthy ecosystems, quality livelihoods, and strong rural economies. However, they recognize that change is costly. Change requires time, knowledge, energy, feedback loops to make effective adjustments, and financial investment. These farmers also recognize that not all new ideas and technologies are equal, not all experiments succeed, and change for the sake of change may not be in the best interest of farmers or society (Morton et al., 2021).

The SfL process for helping farmers better understand the coupled human and natural systems they manage, the many paths toward achieving local and global sustainability, and the development, evaluation, selection, and implementation of new and existing technologies (fig. 2) is as follows:

  1. Engage farmers and their partners in conversations about what works and what does not work; the challenges they face from weather, climate, value chains, and markets; the social and economic pressure to deliver more output with fewer resources; how to manage the land that has become everyone’s business; and their role in addressing uneven prosperity, food security, poverty from farming livelihoods, and the degradation of soil, water, and other resources.
  2. Discuss and debate the reasons, motivations, and risks associated with altering their current production systems, modifying their traditional practices, and experimenting with new methods and technologies.
  3. Develop a vision of what their farm, community, and region might look like if they transitioned to more diverse farming that integrated human and natural systems.
  4. Encourage, educate, and equip farmers to experiment and learn from personal and peer experiences, local knowledge, and scientific research to find practices and cropping systems that work with their unique soil, climate, water access, markets, and knowledge.
  5. Find right-sized technologies for farm systems at various scales and geographies. Explore sources and partners that can offer tools, technologies, and innovations that fit the farm goals, resources, type, and scale.
  6. Create system processes, collect data, and maintain feedback loops that provide information to guide adjustments and decision-making as conditions change and when extreme unexpected events occur.

The SfL farmer leaders have developed a set of core principles that depend on diversity, complexity, redundancy, and extensive feedback loops to guide productivity, adaptation, and GHG reduction to achieve resilience and meet the SDGs. In 2019, these guiding principles were submitted to the United Nations (UN) Koronivia Joint Work on Agriculture (KJWA) workgroup as input to the UN Climate Conference of Parties (COP), and they were recently published by SfL (Morton et al., 2021). The goals of circularity are to couple economic growth with sustainable resource use through management of finite resources and balancing of renewable resource flows, retain materials within biological and technological cycles for as long as possible, and eliminate waste and pollution (Basso et al., 2021). These goals are especially congruent with two of the SfL guiding principles that emphasize a systems approach:

Multi-Benefit Circles of Life

Our food and agricultural systems have a legacy based on Earth’s circles of life, the original circular systems. Some agricultural practices that incorporate circularity are more than 4,000 years old, as documented by King (1911) in Farmers of Forty Centuries. China, Korea, and Japan have maintained soil fertility and productivity for centuries through the reuse of plants (crop rotations and cover crops) and recycling of food, animal, and human waste. Today’s farmers are looking closely at those circular systems and exploring the applicability of ancient practices to their own enterprises.

In a year-long SfL farmer-to-farmer conversation to develop an Iowa smart agriculture vision for the future and provide recommendations for paths forward, one farmer described her family farm as a “circle of life” with continuous improvement, very similar to the idea of circular systems (Iowa, 2021). The phrase “circle of life” resonated with all the farmers participating in the discussion. This Iowa farmer asserted that “my husband and I remind each other that everything we do on our farm is subject to change.” She elaborated that adjustments and adaptations in their diversified crop-livestock system are evaluated as they track markets, weather, disease, and soil and water conditions. Their primary crops (corn, soybeans, and oats) are sold directly to off-farm markets and are also used as inputs to their livestock production, so feed grain and bedding do not have to be purchased. Bedding and manure are managed as outputs, rather than waste materials, and are recycled as grain crop inputs that provide crop nutrients and residues that improve the soil structure and health.

Discussions in SfL farmer workgroups emphasize three non-linear strategies: efficiency, substitution, and redesign (Pretty, 2020). Each strategy helps farmers improve the use of their available land and resources and create better data for feedback loops that guide adjustments in their production systems and make better use of resources. Farmers seeking better results often combine the three strategies to increase profitability, improve soil health, and protect water resources. Another Iowa farmer and his wife, who run a 30,000-head custom wean-to-finish hog operation, raise sheep, poultry, and beef cattle, and grow field crops (soybean, corn, chickpeas, and hay), have combined the three strategies by planting cover crops that can be grazed while improving water infiltration, reducing erosion and soil compaction, and increasing crop yields. Highly erodible lands are planted with native grasses that draw wildlife and insects. This farmer shared with his peers the observation that “alfalfa fields near pollinator plots and woodlands seem to rarely need insecticides, and hawks and eagles eat the small rodents that make farming with cover crops and no-till a challenge.” He has also invested in wind turbines and solar panels to power the equipment for his hog operation, which draws heavily on electricity inputs. Efficiency decisions and technology substitutions (LED lights, variable-pressure well pump) combined with his on-farm power production and recycling of livestock nutrients to field crops reduces off-farm inputs and improves his farm’s circle of life.

These SfL farmer leaders are early experimenters with new technologies, practices, and management approaches. They are also committed to bringing their farmer neighbors along with them, encouraging them to develop systems that are profitable and environmentally responsible, such as reducing nutrient runoff to nearby rivers and streams. A cow, calf, and timber operation in Florida uses a high-intensity silvopasture system to provide other cattle farmers with nontraditional forage and grazes cattle under pine trees for shelter and winter forage to help raise weight before sale. This thriving family operation has achieved diversified production through the symbiotic relationships among animals, grasses, and trees. While cattle and forage production is annual, timber is harvested at longer intervals, thereby increasing the economic sustainability at different scales. As neighboring ranchers and timberland owners work together using well-managed forests as a grazing resource, there are economic returns, nutrients from animal waste are recycled to benefit forage and tree growth, and chemical and mechanical vegetation control under the trees is reduced, as is the fire hazard from accumulated fuel loads.

Farmers learn from each other. For example, an SfL farmer can remind another farmer of the circle of life belowground as well as aboveground in response to management practices. Appropriate application of fertilizers, including nutrient rate, source, form, and placement, must be tracked carefully to maintain the health of a diverse circular system. As one SfL farmer recently observed, “We are in a really unique space. We now have technologies that enable us to place resources effectively and to monitor and evaluate the gains and losses that we create with our management decisions.” Data are essential for management, profitability, and the integrity of the farm ecosystem, and farmers are learning how to use and apply technologies to adapt as conditions change. Biogas production through anaerobic digestion is a widely used technology for recycling animal manures and crop biomass into methane gas (fig. 3). These circular systems can reach beyond a single integrated crop-livestock farm to include agricultural wastes from neighboring farms and other off-site feedstock sources. One SfL crop-livestock producer has invested in a biogas system that generates electricity for the farm and provides farm income as excess biogas is sold to the local electrical utility.

Figure 3. Sievers Family Farms LLC, in Stockton, Iowa, generates biogas from a diversified crop-livestock system that produces diverse rotations of annual crops and beef. Manure and soiled bedding from the cattle barns are mixed with food waste from neighboring industries and harvested cover crop biomass and anaerobically digested to produce energy that is converted to heat and electricity for on-farm use, while the excess is sold to the local electrical utility (graphic by Omar de Kok Mercado, Iowa State University).

U.S. farmers are not alone in their efforts to increase diversity, create loops for nutrient and energy flows, improve productivity, and recycle and reuse waste outputs. Farmers around the world are using whole-farm systems and circular approaches to produce food, make a living, and protect the environment. For example, many small-scale farmers in the Red River delta of Vietnam operate diversified crop-livestock systems that include fish ponds, poultry and larger livestock, vegetable and orchard crops, and a family garden (Morton, 2020a). Traditional fish ponds often contain more than six fish species and have been found to be far more productive than single-species aquaculture (Huong et al., 2018). The use of several species enables a highly productive circular model with nutrient flows that recycle wastes and provide benefits for all species in the pond (Huong et al., 2018). New technologies and production tools are also helping Vietnamese farmers intensify their land use and protect soil resources by growing diverse combinations of high-value vegetable crops (fig. 4) that improve soil properties after intensive rice production (Morton, 2020a). An experimental tool called PermVeg helps farmers select 8 to 17 vegetable crop sequences over a two-year rotation based on their farm priorities, local markets, and weather conditions (Huong et al., 2014). This new tool assists the farmers in planning, planting, and managing crop diversity and guides their decisions for achieving specific outcomes, such as: highest income, lowest labor input but mean profitability, lowest pesticide use but equal or greater profitability, highest diversity using high-profit crops, or low perishability and high profit.

Achieving Circular Systems in Agriculture

Diversification and complexity are the foundation of natural circles of life and are also needed to create effective circular systems in agriculture. However, current agronomic practices and technologies are designed for monocropping systems (Malezieux et al., 2009). New research on system relationships, new concepts for crop management, and multispecies systems will be critical for producers to transition from their current linear systems to circular systems and whole-system farming. Resilience arises from a variety of feedback loops that work in different ways to avert and redirect catastrophes and restore systems, even after a large disturbance (Meadows, 2008). Meta-resilience occurs when a set of feedback loops in one system can restore or rebuild integrity in another system. Mega-resilience arises from adaptive management that fosters learning, creating, redesigning, and the capacity to evolve (Fiskel, 2015). Models that simulate these complex multi-level feedback loops must be grounded in research and applications at the field, farm, and watershed scale to convert theories and good ideas into realistic and workable practices.

Farmers in the SfL Florida Climate Smart Agriculture Workgroup have begun this work by partnering with the University of Florida and other institutions to create an artificial intelligence (AI) hub for agricultural reporting and verification of ecosystem services through sensing technologies. The goal is a national monitoring network with AI-driven approaches to quantify ecosystem services. This type of research by land grant universities, industry and government, and extension is needed to develop the tools that will enable farmers to continuously adapt and provide agricultural products and ecosystem services efficiently and profitably. Work is also needed to inform policymakers as they develop appropriate incentives in support of national goods such as ecosystem services and access to safe, healthy, and nutritious food.

Figure 4. The Red River delta in Vietnam is a dense network of compartmentalized fields watered by canals and ditches that are controlled by sluice gates in dikes. Two-year rotations of high-value vegetable crops with rice have improved the soil properties and increased household incomes (https://www.jswconline.org/content/75/5/109A).

Achieving circular agricultural systems will require farmers to modify their resource inputs and flows by increasing on-farm and farm-to-farm recycling and by redirecting current outputs into inputs for other production systems (Jones et al., 2021). Replacing the traditional “take, make, and dispose” model with a circular “make, use, and recycle” model offers profitable solutions by reducing input costs and recovering income from resources that would otherwise be wasted and could harm the environment. Development and management of whole-farm systems will require farmers to match their knowledge and skills, past experiences, observations of peer systems, and existing equipment and resources with new science, technologies, and innovations. Individual producers must find their own circular systems that work for their particular conditions, and they must be willing to adapt as conditions change. Not all systems will work under all conditions. However, over time, a variety of successful circular agricultural systems will emerge as researchers and farmers monitor, evaluate, redesign, and learn more about the complex relationships between human needs and natural systems.

Farmer-to-farmer learning platforms, like SfL, provide safe spaces where scientific knowledge and local experiences can be shared, where agricultural solutions can be developed for achieving the United Nations SDGs, and where farmers, who manage much of the world’s land resources, can be encouraged to collaborate.

Acknowledgements

Thanks to Solutions from the Land (SfL) for its national and state-level farmer-led workgroups, collaborations with landowners and managers, and partners, including land grant universities and ASABE, as we work together toward achieving circular economies in agricultural and food systems to feed the growing global population and deliver sustainable benefits from the land.

References

Basso, B., Jones, J. W., Antle, J., Martinez-Feria, R. A., & Verma, B. (2021). Enabling circularity in grain production systems with novel technologies and policy. Agric. Syst., 193, article 103244. https://doi.org/10.1016/j.agsy.2021.103244

Carolan, M. (2016). Sociology of food and agriculture (2nd Ed.). Abingdon, UK: Routledge. https://doi.org/10.4324/9781315670935

Engler, C. (2021). A big impact from big thinking. Resource, 28(2), 2. St. Joseph, MI: ASABE.

Fiskel, J. (2015). Resilient by design. Washington, DC: Island Press. https://doi.org/10.5822/978-1-61091-588-5

Hansen, H. O. (2019). The agricultural treadmill: A way out through differentiation? An empirical analysis of organic farming and the agricultural treadmill. J. Tourism Heritage Services Marketing, 5(2), 20-26.

Huong, N. V., Huu Cuong, T., Thi Nang Thu, T., & Lebailly, P. (2018). Efficiency of different integrated agriculture aquaculture systems in the Red River delta of Vietnam. Sustainability, 10(2), article 493. https://doi.org/10.3390/su10020493

Huong, P. T. T., Everaarts, A. P., van den Berg, W., Neeteson, J. J., & Struik, P. C. (2014). PermVeg: A model to design crop sequences for permanent vegetable production systems in the Red River delta of Vietnam. J. Agron. Crop Sci., 200(4), 302-316.

Iowa. (2022). Iowa Smart Agriculture Workgroup. Lutherville, MD: Solutions from the Land (SfL). Retrieved from https://www.solutionsfromtheland.org/iasa/

Jones, J., Verma, B., Basso, B., Mohtar, R., & Matlock, M. (2021). Transforming food and agriculture to circular systems: A perspective for 2050. Resource, 28(2), 7-9. St. Joseph, MI: ASABE.

King, F. H. (1911). Farmers of forty centuries: Permanent agriculture in China, Korea, and Japan. https://doi.org/10.5962/bhl.title.40286

Lal, R. (2020). Advancing climate change mitigation in agriculture while meeting global sustainable development goals. In Soil and water conservation: A celebration of 75 years. Ankeny, IA: Soil and Water Conservation Society.

Lempert, R., Arnold, J., Pulwarty, R., Lempert, R., Gordon, K., Greig, K., ... Lazarus, M. A. (2018). Reducing risks through adaptation actions. In D. R. Reidmiller, C. W. Avery, D. R. Easterling, K. E. Kunkel, K. L. Lewis, T. K. Maycock, & B. C. Stewart (Eds.), Impacts, risks, and adaptation in the United States: Fourth National Climate Assessment (Vol. 2, pp. 1309-1345). Washington, DC: U.S. Global Change Research Program.

Malezieux, E., Crozat, Y., Dupraz, C., Laurans, M., Makowski, D., Ozier-Lafontaine, H., ... Valantin-Morison, M. (2009). Mixing plant species in cropping systems: Concepts, tools and models: A review. Agron. Sustain. Dev.., 29, 43-62.

Meadows, D. H. (2008). Thinking in systems. White River Junction, VT: Chelsea Green Publishing.

Melillo, J. M., Richmond, T. C., & Yohe, G. W. (2014). Highlights of climate change impacts in the United States: The Third National Climate Assessment. Washington, DC: U.S. Global Change Research Program.

Morton, L. W. (2020a). Working toward sustainable agricultural intensification in the Red River delta of Vietnam. J. Soil Water Cons., 75(5), 109A-116A. https://doi.org/10.2489/jswc.2020.0304A

Morton. L. W. (2020b). Social understandings and expectations: Agricultural management and conservation of soil and water resources in the United States. In Soil and water conservation: A celebration of 75 years. Ankeny, IA: Soil and Water Conservation Society.

Morton, L. W., Hatfield, J., Kawamura, A. G., Kimble, M., Lovejoy, T., O’Toole, P., ... Yoder, F. (2021). 21st Century agriculture renaissance: Solutions from the land. Lutherville, MD: Solutions from the Land (SfL).

Pretty, J. (2020). New opportunities for the redesign of agricultural and food systems. Agric. Human Values, 37(3), 629-630. https://doi.org/10.1007/s10460-020-10056-2

Rowntree, J. E., Stanley, P. L., Maciel, I. C., Thorbecke, M., Rosenzweig, S. T., Hancock, D. W., ... Raven, M. R. (2020). Ecosystem impacts and productive capacity of a multi-species pastured livestock system. Front. Sustain. Food Syst. https://doi.org/10.3389/fsufs.2020.544984

Rudel, T. K., Timmons Roberts, J., & Carmin., J. (2011). Political economy of the environment. Ann. Rev. Sociol., 37(1), 221-238. https://doi.org/10.1146/annurev.soc.012809.102639

Schnaiberg, A. (1980). The environment: From surplus to scarcity. New York, NY: Oxford University Press.

SfL. (2013). Agriculture and forestry in a changing climate. Lutherville, MD: Solutions from the Land.

Stone, G. D., & Flachs, A. (2018). The ox fall down: Path-breaking and technology treadmills in Indian cotton agriculture. J. Peasant Studies, 45(7), 1272-1296. https://doi.org/10.1080/03066150.2017.1291505

Tamburini, G., Bommarco, R., Wanger, T. C., Kremen, C., van der Heijden, M. G., Liebman, M., & Hallin, S. (2020). Agricultural diversification promotes multiple ecosystem services without compromising yield. Sci. Adv., 6(45), eaba1715.

Tittonell, P. (2014). Ecological intensification of agriculture: Sustainable by nature. Current Opin. Environ. Sustain., 8, 53-61. https://doi.org/10.1016/j.cosust.2014.08.006

UN. (2021). United Nations Sustainable Development Goals. New York, NY: United Nations. Retrieved from https://www.un.org/sustainabledevelopment/sustainable-development-goals/

Walker, B., & Salt, D. (2006). Resilience thinking: Sustaining ecosystems and people in a changing world. Washington, DC: Island Press.