Brazil's sugarcane crop could help reduce carbon emissions

Brazil’s sugarcane crop gets larger every year, and that could be good for the planet.

Sugarcane has become one of the South American country’s top crops – not to use for sugar to be used in food, but to convert into ethanol. That crop has the potential to reduce global carbon dioxide emissions by more than 5 percent, according to an analysis led by Dr. Stephen P. Long of the University of Illinois.

Maximizing that potential would take work, said the research team, which included scientists from Brazil’s University of Sao Paolo. Land use would need to make room for more cane, first of all, they said – fields totaling the size of Texas and California together.

But the sugarcane crop could be expanded without encroaching on environmentally sensitive areas or cutting into crops of human, the researchers said.

“We’ve kept the proposed sugarcane production within the area that can be legally converted,” Long said in a press release.

The team came to their conclusions by developing a new model to study Brazil’s sugarcane and other agricultural production. They took into account how sugarcane crops behave in various types of soil, with varying amounts of rain, and in other environmental conditions found around the country.

“Most models used to predict future crop production are statistical models that really don’t take full account of the way changes in water, carbon dioxide and temperature interact to aect sugarcane production,” Long said. “We’ve used a mechanistic model here that grows the plant, so it’s driven by the factors that the plant is responding to on an hourly basis.”

They also took into account that Brazil uses every part of the sugarcane crop – even the stem residue is used to power the mill that extracts the ethanol – and the higher efficiency of sugarcane versus corn in producing ethanol.

Converting more of Brazil’s agricultural land to ethanol production could go a long way toward helping the world reach the goals set by the Paris agreement in 2015, which includes working to keep global temperatures no more than 2 degrees Celsius higher than in pre-industrial times.

Expanding Brazil’s sugarcane crop – and returning fallow sugarcane fields to production in places like Hawaii, the Caribbean and other regions – could put a large dent in that goal, the researchers said.

“The only way we’re going to get there is to have a massive reduction in net CO2 emissions,” Long said. “No single solution will get us there. We’ll need to implement a whole series of incremental steps. We’re trying to point out that this could be a very important increment, and one that could be realized in a timely manner.”

The analysis has been published in the journal Nature Climate Change.

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By Kyla Cathey, Earth.com staff writer

Image credit: Depositphotos photo by Jaykayl