Tyler Lark, a geographer at the University of Wisconsin-Madison, grew up among farms, working at a neighbor’s dairy, vaguely aware of the tension between clearing land to grow food and preserving wildlife. As an engineering student working on water projects in Haiti, he saw an extreme version of that conflict: forests being cleared for firewood or to grow crops, with soil erosion, environmental pollution and increasing poverty. “I think it was that experience that told me, ‘Hey, land use matters,'” he says.
He decided to explore how farmers are transforming landscapes through their collective decisions to plow grasslands, cut trees or drain wetlands — decisions that are at the heart of some of the planet’s greatest environmental challenges, as well as spark controversy. Lark bears professional scars from the recent clash in one of the fiercest of these battles: the debate over growing crops used to make fuel for cars and trucks.
About 15 years ago, government incentives helped spark a biofuel boom in the United States. Ethanol plants now consume about 130 million tons of corn per year. It’s about a third of the country’s total corn crop, and growing that corn requires more than 100,000 square miles of land. In addition, more than 4 million tons of soybean oil is converted to diesel fuel every year, and that number is growing rapidly.
Scientists have long warned that producing biofuels on this scale comes at a cost: it claims land that could otherwise grow food or, alternatively, grass and trees that take carbon from the air and provide a home for birds and other animals in the world. the wild. But government agencies, based on the results of economic models, concluded that those costs would be modest and that replacing gasoline with ethanol or biodiesel would help meet greenhouse gas reduction targets.
Lark and a group of colleagues recently revived this debate. In a February 2022 study, they concluded that the law that unleashed the ethanol boom persuaded farmers to plant corn on millions of acres of land that would otherwise have remained grassland. Environmentalists have long feared that biofuel production could lead to deforestation abroad; this article showed that a similar phenomenon was occurring in the United States.
That land conversion, the scientists concluded, would have released large amounts of carbon dioxide and other greenhouse gases into the air, and would make ethanol fuel just as bad for the climate as the gasoline it’s supposed to replace.
Farmers and biofuel trade groups lashed out at these findings — and against Lark himself. A biofuels industry association demanded that he and one of his co-authors be barred from a review panel of government experts on renewable fuels.
The dispute came at a time when world events exposed the trade-offs of biofuels. Less than two weeks after Lark’s paper came out, Russia invaded Ukraine, triggering a spike in prices for both food and fuel — already scarce and expensive due to the pandemic. Biofuel supporters have called for incentives to mix more ethanol with gasoline to lower gasoline prices. Proponents of anti-hunger demands fewer production of biofuels, to free up land to grow more food. And natural ecosystems keep disappearing.
