Sustainable production is a concept and goal that’s been around for decades, but drew particular attention on the world stage in 2015 when the UN General Assembly adopted a set of 17, interlocked Sustainable Development Goals (SDGs), which included an end to hunger, a restoration of our water resources and climate action.

Now, there is much talk among those in the sector, academics and policymaker over the concept of circular agriculture. It is a way of going forward that focuses on reducing external inputs, closing nutrient loops, regenerating soils and minimizing ag’s impact on the environment.

If practiced on a wide scale, circular agriculture can optimize resource requirements and the ecological footprint of agriculture. It can also help ensure a reduction in land use, chemical fertilizers and waste, which makes it possible to reduce global carbon emissions that contribute widely to climate change.

As acknowledged in the SfL report issued this past February – 21^st Century Agriculture Renaissance: Solutions from the Land – “Linear economy food and agricultural production systems have losses and wastes along the full value chain…Linear economy systems can be transitioned into circular economy systems by 1) recovering and recycling discarded wastes for productive use, 2) keeping products and material in use, 3) regenerating and redesigning natural systems, and 4) providing economic benefits and incentives.

Citing findings by the American Society of Agricultural and Biological Engineers (ASABE), the report says agriculture and our food system can no longer be thought of as a linear journey through pre-production, production, post- harvest, and consumption that adds land, water, energy, nutrients, labor, and capital as inputs, all the while abandoning the waste lost from the process as discards.

“Rather,” the report states, “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 simultaneously layered onto each other, interacting spatially and continuously ‘looping’ forward, back, and sideways.”

Ag circularity mimics that in nature, the original circular system. It is not linear and has no waste. Everything is of value. Circular systems are dynamic, continually adjusting and adapting as other parts of the system shift and change.

For example, research shows that land-based forest, plant and soil ecosystems have the potential to remove about 30 percent of climate-warming carbon dioxide (CO₂) from human activities annually when they become a sink for carbon. Plants use CO₂ for growth and along with soil nutrients, soil and water, is a key factor in plant biomass and yields. When plant biomass dies, microbes in the soil feed on the biomass roots and in conjunction with soil moisture and sunshine (or lack thereof) can accelerate or slow the decomposition process.

As SfL’s 21^st Century Renaissance Report notes, food and agricultural systems are much more than simple farms nested in rural landscapes producing one or two crops. They are complex with capacities to produce multiple benefits ranging from safe and nutritious food supplies, renewable fuels and energy, high quality water, retention and storage of soil carbon, enhancement of wildlife and biodiversity, and profitable livelihoods. The resilience of food and agricultural systems, the work group says, have a legacy based in our planet’s circle of life, the original circular system.

SfL’s commitment to the promotion of circular agriculture is being demonstrated today with the participation of President Ernie Shea in a National Academy of Engineering forum on Complex Food and Agricultural Systems: Engineering for Sustainability and Resilience. Shea will highlight three examples of circular systems in Iowa, including one that demonstrates an on-farm scale of circularity, another operation that shows a watershed scale and a third farming operation that demonstrates circularity on a national scale.

Means of achieving circularity can come through efficiency, which focuses on reducing wasteful management practices and making better use of on-farm and imported resources. Substitution is a strategy that calls for the replacement of current technologies and practices with more sustainable, less wasteful practices. Redesign would enable the use of integrated land management and diversification to alter the straight-line path into a circle of life path by focusing on within-farm and landscape level interdependencies.

Each of the three approaches can help other land and livestock managers and landowners make better use of their existing land and resources to create new feedback loops and more circular systems within the farm enterprise and, ultimately, across all agricultural landscapes. Circularity is an approach that has been adopted by other sectors and would serve agriculture well. The sector has been reinventing itself and the way it produces for centuries. The 21^st Century may mark the beginning of a broader way of working the land that accelerates production and eliminates waste that can reduce yield and reduce income. SfL urges leaders in the sector and policy makers to explore the circular approach to agriculture.