Simple changes in Minnesota’s forestry, farming could slash carbon emissions
Managing the nations landscapes with carbon in mind from prairies to farms to urban and northern forests could cut greenhouse gas emissions by up to 21 percent annually in the United States, about equal to what all the cars and trucks on the road produce.
And Minnesota is among the states that could do the most: It ranks 8th overall with the potential to reduce net carbon emissions by up to a third, according to a study published Wednesday in the journal Science Advances.
The strategy wont solve climate change on its own, said the lead author, Joe Fargione, an ecologist with The Nature Conservancy. But the study, which measured 21 specific practices, illustrates the potential that such natural climate solutions could have.
It reduces the risk of catastrophic climate change, which is going to be hard to do from the energy sector alone, he said.
Moreover, they are all changes that can be adopted by individual landowners, homeowners and farmers, or local and state governments, while providing the added benefits of cleaner water and air and healthier soils, said Bonnie Keeler, a professor at the University of Minnesota who studies the social value of nature.
This is not a radical shift in behavior, she said. Its good land management.
But the shift would come at a steep price for some, at least in the short run. For example, a significant portion of the benefit in Minnesota would come from planting cover crops, which protect bare soil from erosion and capture nitrogen something farmers would have to choose to do. And while use of cover crops such alfalfa is on the rise, especially to reduce runoff and fertilizer contamination of water, its a steep climb, said Paul Porter, a U of M agronomy professor.
At least in the near term, we are not going to do this on vast acreages, he said. For that to change, he said, it has to be economical for farmers, and right now its not.
The study examined what contributions natural climate solutions could make in achieving the U.S. carbon reduction goals established by the Paris Climate Accord 26 to 28 percent below 2005 emissions by the year 2025.
The authors, 36 researchers from 22 conservation and academic institutions, then estimated the amount of carbon that would be sequestered by 21 different land management practices without reducing the amount of food and fiber produced by growers. That 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.
At most, assuming zero cost, the country could reduce carbon by 21 percent of the net emissions it produced in 2016. The vast majority would come from reforesting some lands, primarily in the northeast and south central regions of the country, but excluding productive farmland. Extending harvest cycles on privately held timber lands would also provide a significant benefit.
In Minnesota, eleven of the practices could be used to reduce 33.75 percent of the 80 million net tons of carbon the state produces each year. An estimated 50 million tons is already held in the land, primarily in the soils, grasses and forests that make up its primary ecosystems.
The single biggest thing we need to do is not convert forest to non-forest use, said John Rajala, who manages a family-owned timber and milling company in Deer River. Second, is to promote long-lived species on as many sites as possible.
Rajala Companies has been managing its 20,000 acres of timber land with those goals in mind for years. It plants long-lived, harvestable species like white pine, but also those that will prevail in the warmer and wetter decades to come.
The products we make are almost as important as the way we manage the forest, he said.
His company makes long-lived 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 throw away consumerism, he said.
Josephine Marcotty 612-673-7394