Spurred largely by high crop prices and increased demand, landowners in the Great Plains have converted hundreds of thousands of acres of native grasslands over the past several years into fields of corn and soybeans.
Environmentalists have long warned that increased conversion to cropland, while boosting the pocketbooks of farmers, has led to a loss of habitat for wildlife and declining water quality. But researchers are beginning to quantify that it's also meant a significant loss of the soil's potential to store carbon.
Armed with a model that takes into account emissions data from grassland conversion, environmentalists and the Agriculture Department hope to harness the financial incentives of carbon markets to slow the rate of declining native grassland in the environmentally sensitive Prairie Pothole region. In a first-of-its-kind program, they're offering up carbon offsets to farmers in several North Dakota counties who agree to preserve their grassland.
"The basic idea is that there's a lot of carbon stored in these grasslands," said Peter Weisberg, program manager at the Climate Trust. "When you convert it, more carbon decomposes and is lost."
In 2011, USDA awarded Ducks Unlimited a $161,000 grant to develop a way to monetize the preservation of grassland using carbon markets. The organization partnered with the Climate Trust, the Nature Conservancy, the Environmental Defense Fund and Terra Global Capital and announced last week that it has successfully developed a way of quantifying avoided carbon losses from grassland conversion.
Using the model, which has cost about a half-million dollars to develop, Ducks Unlimited has begun enrolling farmers in eight North Dakota counties in a pilot program to provide farmers with money from the sale of carbon offsets.
Under the pilot, Ducks Unlimited has agreed to find carbon buyers for landowners when they agree to preserve grassland. Ducks Unlimited currently has an inventory of offset options from landowners; once money becomes available, the conservation group will go out and sell the offsets to entities such as companies that want to demonstrate sustainability. Ducks Unlimited will then pay the farmer market value for the carbon.
"It's an option to buy their carbon once a buyer is found," said Stephen Adair, Ducks Unlimited director of operations for the Great Plains region.
The program was recently approved by the American Carbon Registry, a nonprofit organization that certifies carbon offset projects.
So far, 114 landowners have enrolled. USDA's Natural Resources Conservation Service, which awarded grants for nine climate change initiatives in 2011, hailed the program as a way to help boost the rural economy.
"This project provides Northern Great Plains producers with new ways to earn income from conservation activities, expanded opportunity for outdoor recreation and an opportunity to create jobs in their communities," Robert Bonnie, USDA undersecretary for natural resources and the environment, said in a statement.
The idea for this type of carbon farming stems from the high rate of grassland conversion in the Corn Belt and Northern Plains over the last few years.
Between 2006 and 2011, landowners in the western Corn Belt states of North Dakota, South Dakota, Nebraska, Minnesota and Iowa converted 1.3 million acres of grassland into cropland, a study published earlier this year by South Dakota State University researchers found. USDA's Economic Research Service found producers in just the Northern Plains states converted 750,000 acres of grassland to cropland between 1997 and 2007.
Much of the conversion has occurred in the Prairie Pothole region that is an important habitat for about half the nation's migratory waterfowl.
"You can hardly drive anywhere without seeing native grasslands or [Conservation Reserve Program] land being plowed up and put back into cropland," Adair said. "I compare it to the loss of rainforest in Brazil, right here in our backyard."
The conversion of grassland in the Prairie Pothole region has emitted between 20 million and 75 million tons of carbon dioxide into the atmosphere, according to studies.
The federal government operates rural conservation programs, such as the Conservation Reserve Program, to provide farmers with financial help to conserve land in easements or make environmental improvements on their lands. But environmentalists worry that the combination of the federal ethanol mandate and increased Chinese demand for U.S. agricultural goods has made plowing up the land to plant corn and soybeans more financially attractive than preserving it.
Under the carbon pilot program, enrolled farmers need to demonstrate that that land would be at least 40 percent more valuable as cropland than grassland in order to plant crops in a field of grassland. The figure was borrowed from the U.N. Climate Action Programme's avoided deforestation protocol.
A major challenge has been writing a protocol that's rigorous enough to meet the offset requirements of California's climate change program but still simple enough to persuade an agricultural producer to sign up.
The biogeochemical model used to account for the carbon lost when grasslands are converted takes into account several factors, including existing carbon stocks, soil type and weather conditions. It can be used both on a property-level scale and to measure the carbon lost on a regional scale.
"It's really new territory. We're struggling a little bit with the lack of rigorous data around agricultural practices," said Ashley Rood, project manager at the Environmental Defense Fund who helped with the editing and writing of the protocol.
Another challenge has been that farmers are more adaptive with the way they manage their lands and will make adjustments as needed, "rather than following to the tee a particular methodology," Rood added.
"The way that offsets are created is sort of looking at polluting entities and permanently offsetting the pollution from a power plant," she said. "The rules are set up for power plants and not for agriculture."
Climate change can be a touchy subject among the agricultural community. Most producers are concerned more about potential government regulations stemming from climate change than the damage of droughts, floods and extreme weather, according to a recent survey of farmers this year by University of California, Davis, researchers (ClimateWire, Sept. 12).
In approaching farmers for the program, Adair said, Ducks Unlimited talks about the changing climate but not about whether recent extreme weather events were driven by man.
"I think everybody is pretty accepting that climate change is happening, that we have these extreme events, that things are tending to be warmer. We don't really discuss what the cause is," Adair said. "Is it coming from man or a natural cycle? It can start to get emotional and political. It is happening, and keeping this carbon in the ground can help mitigate that. People are very comfortable at that level."
In selling the pilot to farmers, Adair said, the conservation group emphasizes not only the emission reduction potential but also the myriad other environmental benefits that come from preserving grassland. Those include improvements to water quality and soil health, and more habitat for the waterfowl that call the area home.
A major selling point is that the program is voluntary, said Rood of the Environmental Defense Fund.
"I think that a lot of them are interested in being part of the solution, and this is a much better way to get people part of the solution," Rood said. "It's a choice rather than a requirement."