资源环境科技发展态势分析平台

The land sector in the United States contains a pool of carbon—carbon stored in soils, forests, and other vegetation—that is more than 50 times the nation’s total annual greenhouse gas emissions as of 2019, with forests alone storing about 28 times those total emissions [1]. This carbon pool has grown steadily over the past several decades, as the amount of atmospheric carbon absorbed by vegetation has exceeded the land sector’s own emissions (e.g., through forest fires, conversions to other uses, or harvesting forests). In 2019, the land sector removed nearly 800 million metric tons of carbon dioxide equivalent (MMT CO₂e) from the atmosphere—roughly equal to 12 percent of total US emissions. Accordingly, the land sector should be thought of as a “negative-emissions” sector.

In contrast, agricultural production activities generate net-positive greenhouse gas emissions. In 2019, agricultural activities and electricity use accounted for about 11 percent of total US greenhouse gas emissions (Figure 1)—primarily in the form of methane from the digestive processes of livestock and manure management, along with nitrous oxide (N₂O) from agricultural soil management [2].

This explainer reviews the federal policy options for increasing land-related carbon storage and reducing N₂O and methane emissions from agricultural land uses and production activities.