A study regarding land use changes has shown that an increase in biofuel production in the United States may cause an increase in greenhouse gas emissions.

The study, published in the online journal Sciencexpress, was led by Timothy Searchinger, visiting research scholar at Princeton University, and was worked on by scientists at Iowa State.

Amani Elobeid, associate scientist at the Center for Agricultural and Rural Development at Iowa State and a co-author of the study, said she and other colleagues at Iowa State began studying scenarios that would increase ethanol production, such as a change in crude oil prices.

Iowa State’s CARD uses international scientific models to measure the global impact of such possible scenarios. Elobeid said she and her colleagues used these models to evaluate how an increase in biofuel production would effect other crop prices and how that would, in turn, affect land use in the United States and abroad.

Searchinger and his colleagues then worked with ISU scientists to translate their data to reflect environmental impacts.

The study, published Feb. 7, says that if farmers worldwide convert forests and grasslands to croplands, an increase in biofuels production would follow and, in turn, conclude with an increase in greenhouse gas emissions.

According to the study, the plowing up of these lands would lead to an increase in atmospheric carbon dioxide, as the plants that were previously on the land remove carbon dioxide from the atmosphere. The decomposition or fire used to clear the land for new crops would also add carbon emissions, according to the study.

Biofuels have often been viewed as better for the environment than fossil fuels because the plants they are made from initially take carbon out of the atmosphere through photosynthesis. Pat Schnable, professor of agronomy, explained that this aspect of biofuels initially offered the hope of a neutral carbon cycle for a fuel.

Because of this, there have been recent political moves in favor of biofuels. In December, President Bush signed legislation that called for ethanol production to reach 36 billion gallons per year by 2022, according to an Associated Press article.

Elobeid said the article in Sciencexpress helped “contribute to the information pool policy-makers have.”

“It’s really just a contribution to the debate,” Elobeid said. She said looking at biofuels’ impact on food prices and land use was uncharted territory.

“I think this is one of the first steps,” said co-author Simla Tokgos, associate scientist the CARD. “I’m sure there will be more studies on this.”

The study said that if biofuel production were to increase, biofuels would eventually be able to “pay back” the emissions they create, since they are made from plants that undergo photosynthesis. Thus, producing biofuels would eventually take more carbon out of the atmosphere than it puts in. Such a cycle would only happen over a long time, according to the study.

In the meantime, according to the study, biofuel production would actually cause greenhouse gas levels to rise for thirty years before helping to reduce them.

Robert Anex, associate director of Iowa State’s Office of Biorenewable Programs, found faults with a number of elements in the Sciencexpress article. For one thing, he said, agriculture and biofuels themselves will change over the years, and the authors of the study “only envision biofuels that require land that competes with agriculture.”

“I think it’s going to be a whole mixture of systems [that replace fossil fuels],” Anex said. He said scientists already know that using only grain as a substitute for fossil fuels will not work, and that conservation will have to be a big part of the solution.

“There is no future scenario that anybody looking at this [sees] we can continue to use more and more [fuel], and we’re going to find an amazing fuel,” Anex said.

Anex said the study further suggests that it is better for farmers to be poor, since it envisions a negative situation brought about by rising crop prices.

“We want prices to go up,” Anex said. “We want farmers to be making more money.”

Anex said that, while he did take issue with these aspects of the study, he said it was correct in showing “we’re not going to do it all with biofuels.”

“I don’t think anyone’s suggested that we will,” Anex said.