Farms and forests seen as key in climate strategy
Smarter practices could curb emissions from greenhouse gas
Managing the nation's landscapes with carbon in mind — from prairies to farms to urban and northern forests — could cut greenhouse gas emissions as much as 21 percent annually, or about equal to the discharge of all cars and trucks on the road today.
The strategy won't solve climate change on its own, according to a new study. But the study, which measured 21 specific practices, illustrates that such “natural climate solutions” have enormous potential.
“It reduces the risk of catastrophic climate change, which is going to be hard to do from the energy sector alone,” said lead author Joe Fargione, an ecologist with The Nature Conservancy in Minneapolis.
Moreover, they are all changes that can be adopted by individual landowners, homeowners and farmers, or by local and state governments, while providing the added benefits of cleaner water and air and healthier soils, said Bonnie Keeler, a University of Minnesota professor who studies the social value of nature.
“This is not a radical shift in behavior,” Keeler said. “It's good land management.”
But the shift would come at a steep price for some, at least in the short run. Planting cover crops protects bare soil from erosion, consumes excess nitrogen and pulls carbon from the air. But that's something farmers would have to choose to do. And while use of cover crops such as rye is rising, especially to reduce runoff and fertilizer contam-
ination of water, it's a steep climb, said Paul Porter, a University of Minnesota agronomy professor.
Farmers “are not going to do this on vast acreages,” at least in the near term, he said. For that to change, he said, “it has to be economical” for farmers, and right now it's not.
The study examined what contributions natural climate solutions could make in achieving the U.S. carbon reduction goals established by the Paris climate agreement — emissions that are 26 to 28 percent below 2005 levels by 2025.
List of practices
The authors, 36 researchers from 22 conservation and academic institutions, then estimated the amount of carbon that would be sequestered by 21 land management practices without reducing the production of food and fiber. The practices included replanting forests, better management of nitrogen and manure, planting cover crops, extending the life of trees before harvesting them for timber, and restoring low-quality croplands to wetlands and prairies.
21 percent reduction
At most, under one scenario, the country could reduce carbon by 21 percent of the net emissions it produced in 2016. The vast majority would come from reforesting land, for example, that has been lost to urban sprawl, primarily in the northeast and south central regions of the country. That would exclude productive farmland.
“We want to conserve good farmland,” Fargione said.
Extending harvest cycles on privately held timber lands would also provide a significant benefit.
“The single biggest thing we need to do is not convert forest to nonforest use,” said John Rajala, who manages a familyowned timber and milling company in Deer River, Minn. “Second is to promote long-lived species on as many sites as possible.”
Timberland goals
Rajala Cos. has been managing its 20,000 acres of timberland with those goals in mind for years. It plants long-lived, harvestable species such as white pine, but also those that will prevail in the warmer and wetter decades to come.
Rajala's company makes durable construction materials and cabinets that can last for decades, rather than short-lived consumer products that contribute to climate change as soon as they get tossed — “so we stop this cycle of throwaway consumerism,” he said.
“The products we make are almost as important as the way we manage the forest,” Rajala said.