Earth Day in the year of the farm bill

Earth Day reminds us of the importance of the soil, water and air upon which our health, prosperity and food security depend. The good news is that, on average, humans are better nourished now than at any time in human history, although nearly 1 billion people are still undernourished. The bad news is that our agricultural achievements have come as the expense of extensive air and water pollution and a changing climate.

Crop and livestock systems always entail environmental compromises when native lands are converted to agriculture and when fertilizers are applied to increase crop production. Excess nutrients run off of farmlands and animal production facilities, ending up in streams, groundwater and estuaries, where they pose human health risks and promote damaging algal blooms. Food production contributes between 21 percent to 37 percent of total global greenhouse gases causing global warming.

One of the greatest challenges of our time is to produce abundant, affordable and nutritious food for today’s 8 billion people, and for the 10 billion to 11 billion people within the next 30 to 50 years, while also sustainably stewarding land and water resources and a stable climate so that future generations will enjoy the necessary soils, water and climate required to meet their needs for food, good health and economic prosperity.

Every five years, the U.S. Congress establishes policies and funding through the giant legislation package known as the “farm bill,” and we are in one of those years. The urgency for effective policies that serve dual goals of agronomic productivity and environmental stewardship, including large reductions of greenhouse gas emissions, could not be greater. More good news is that the 2023 Farm Bill will likely devote considerable attention to advancing “climate smart-agriculture” and “regenerative agriculture.” As usual, however, the devil and the goodness are in the details, including what these popular catchphrases really mean and parsing out which ideas are most worthy of support.

There are dozens of potential interventions that this year’s farm bill could adopt, but three rise to the level of being truly transformational, significantly slowing climate change while increasing agricultural productivity.

1) Reduce methane emissions from livestock by more than half through existing technologies and accelerated research and development. Because it is relatively short-lived in the atmosphere, reducing methane sources would almost immediately slow climate change. While much methane mitigation focuses on the energy sector, livestock is the single largest source of methane, mainly the burps of cows and cattle, sheep and other ruminants.

Unfortunately, reducing livestock methane emissions has received paltry funding despite some promising developments with feed additives and an unrealized potential from state-of-the-art research on the rumen microbiome. An added bonus is that energy that cows now lose as they produce methane, could be redirected to producing more milk and beef, thus reaping an economic benefit for farmers and a more efficient food system for humanity.

2) Give USDA a mandate to harmonize and coordinate monitoring, reporting and validation (MRV) of tradeable soil carbon credits. In contrast to methane, the proliferation of private and public money wishfully chasing soil carbon credits has gotten ahead of the soil science, agronomy and social science needed to design and implement a credible system for effectively farming for carbon. The current Wild West marketplace of soil carbon credits urgently needs an MRV sheriff for this outpouring of good intentions to actually lead to verifiable sequestration of carbon in agricultural soils and the accompanying improved soil fertility and economic benefits to farmers.

3) Authorize and increase funding for the Agricultural Advanced Research and Development Authority (Ag-ARDA) to transform management of the nitrogen cycle in agriculture. Such ground-breaking innovations include making fertilizers using renewable energy, feeding amino acids and other forms of nitrogen directly to livestock, and breeding crop varieties that make more efficient use of nitrogen. Such developments would start decoupling the current dependency of food production on inefficient uses of nitrogen that wreak havoc on the land, air and water, including emissions of nitrous oxide, a potent greenhouse gas and stratospheric ozone destroyer. It is difficult to estimate how big the effect could be — but reducing nitrate leaching and nitrous oxide emissions by half seems within reason. At the same time, such transformational improvements in efficiencies would boost yields, profitability and food security, as well as reduce global demand for converting forests to croplands.

The 20th-century Earth Day discussions often focused on debates about protecting the environment or promoting economic productivity — but not both. In the 21st century, Earth Day is a time to say: Yes, we can promote productive agriculture to meet human needs and we can do so intelligently as good stewards of the Earth.

Eric A. Davidson is professor of the University of Maryland Center for Environmental Science, principal scientist for Spark Climate Solutions and the author of “Science for a Green New Deal: Connecting Climate, Economics and Social Justice,” Johns Hopkins University Press, 2022.