by Glenn Pollock

    While it’s easy to observe a prairie’s natural beauty, you have to look below the surface to appreciate the work it does to alleviate climate change – because that’s where carbon sequestration occurs. What does the Audubon Prairie have to do with carbon sequestration?
    Animals are the primary natural source of atmospheric carbon dioxide, the most common greenhouse gas, while human activities — mainly energy production – account for the vast majority of the remaining CO2 emissions.  Audubon Society of Omaha purchased and preserves its prairie lands to provide critical habitats for insect and other pollinators, birds, snakes and many species of animals. But there’s more.
    It turns out that tallgrass prairies are great at biologic carbon sequestration – storing atmospheric carbon dioxide in the soil. Biologic carbon sequestration removes carbon from the atmosphere, which helps counter the negative impacts of climate change. In fact, prairies like ours are even more effective at reducing atmospheric CO2 than trees. Two-thirds of the biomass of prairie plants lie underground; the opposite is true of trees. Of course, we all love trees, but when they die, they release carbon dioxide back into the air. When grassland plants die, as much as two-thirds of the dead material does not break down and emit carbon dioxide. Instead, it simply remains underground.
    I was curious about just how much carbon is stored under the Audubon Prairie, so I went online – and found what seemed like thousands of academic articles exploring the calculations. Eventually, I estimated that each acre of our prairie sequesters approximately 1-5 tons of carbon per year.
    Okay, let’s do the math. First, let’s assign a value of 2.5 tons of carbon per acre per year for our purposes. Next, let’s divide Audubon Prairie into three segments: virgin prairie, the 22-year restoration, and the 1-year restoration. Here’s what I came up with:
• The virgin prairie. Because it’s been around for thousands of years, it has no doubt reached its maximum storage level. The upper two feet of soil may be made up of as much as 50 percent carbon compounds. Even more carbon may be stored as far down as six feet below the surface.
•    The 22-year restoration. To come up with this figure, I multiplied 7.25 acres by 22 years and then by two tons, which resulted in a total 51.25 tons of carbon.
•    The 1-year restoration. It’s too early to calculate the exact number of tons of carbon sequestered under these 3.25 acres because the plants are still new and relatively small.
    To understand the magnitude of global climate change, remember that all of the carbon stored under the Audubon Prairie grasslands does not make up for the amount of carbon dioxide each of us releases into the atmosphere during the course of our daily lives – breathing, driving, cooking with natural gas or propane, heating and cooling our homes, and more. But the prairie certainly helps.
    It’s also important to remember that some government agencies understand and value efforts to address climate change. My farmer friend near Crescent, Iowa, just planted 80 acres of his hilly farmland with native prairie plants, which will help offset his carbon emissions while preventing soil from running into the Missouri River. He signed up for the Conservation Reserve Program offered by the USDA to help pay for the project.