U.S. agricultural producers have long understood that healthy soil is a critical requirement for the production of our nation’s food supply. They also know that as the world’s population grows by more than 25 percent over the next 30 years, meeting the increased global demand for food cannot come at the expense of ecological health and environmental quality.
America’s farmers, who work and live on their lands every day, remain in the best position to develop and implement the management practices that can increase soil quality, productivity and resilience to drought and flooding (and, as a result, boost farm income). These practices also have the benefit of reducing greenhouse gas (GHG) emissions into the atmosphere, mitigating the growing impact of a changing climate.
To build on a drive to improve soil health that has become a burgeoning interest among U.S. farmers in recent years, policies must be implemented which enable them to scale up practices that boost production, reduce runoff into neighboring waters, increase organic content and enhance biodiversity, nutrient cycling and other ecosystem services.
These statutes, policies and programs can help promote no- or reduced-tillage practices and increase crop diversity, rotation and cover crops – all land management practices that improve soil health, productivity and resilience.
No-till and reduced-till practices – now in use on some 40 percent of the nation’s cropland – leaves residues behind, greatly reducing and, in some cases, virtually eliminating soil erosion. They also enhance water infiltration and retention and promote biodiversity.
Research shows that by growing and rotating a variety of crops – wheat, oats, sorghum and alfalfa and other legumes, as examples – within what is otherwise a limited rotation of corn and soybeans, it is possible to produce high yields for each crop in the rotation, control pests and weeds with less reliance on purchased inputs. The practice can also enhance soil fertility with less need for synthetic fertilizers.
Cover crops, though not yet broadly implemented, represent another practice that is growing among U.S. agricultural producers. Grasses, legumes and other plants grown between rotations of commodity crops help manage soil fertility, soil quality, water, weeds, pests and diseases; cut input costs; and enhance biodiversity and wildlife habitat.
With the agronomic benefits of these practices come the reductions they offer in emissions of carbon dioxide (CO2), the most common of GHGs causing climate change. Given that carbon in the soil releases nutrients for plant growth, promotes the structure, biological and physical health of soil, and is a buffer against harmful substances, practices that capture carbon, reduce CO2 emissions and build organic content in the soil are “win-win” solutions.
An example of carbon capture from crop production comes in an analysis of 95,000 soil samples collected from farmer’s fields across eastern and central South Dakota between 1985 and 2010. The findings support the theory that many of the surface soils in the region became carbon sinks when seeded with corn produced for ethanol and other uses.
While U.S. production agriculture contributes some 9 percent of the GHGs emitted in this country, the sector has the potential to achieve a reduction of some 20 percent of all emissions. Given the impact that scientists say climate change is having on agriculture – drought, wildfires, flooding, tornados, shifting planting and harvesting seasons – farmers understand the role their land management practices can play in not only building resilience to these impacts into their operations, but also contributing to the efforts to mitigate those impacts.
There are some state initiatives that are attempting to broaden the role agricultural producers can play in these efforts to stem climate impacts. In the past 18 months, two states – California and Maryland – have created Healthy Soils Programs to encourage the adoption of these practices. Other states have similar legislation on the books. Private sector efforts include the North Carolina-based Soil Health Institute, which has long sought to safeguard and enhance the vitality and productivity of soil through scientific research and advancement.
However, more needs to be done. Solutions from the Land (SfL) is readying a state-by-state campaign to encourage widespread adoption of Healthy Soils enabling policies. SfL urges stakeholders to join in this effort to develop consensus among policy makers and opinion leaders around state-specific soil health programs that can foster a wide range of economic, environmental and public health benefits.