Brazil Sugarcane Growth Can Meet Biofuel Need and Not Drive Deforestation: Study

by Claire Asher (South Africa Today/Mongabay) -Sugarcane crop production in Brazil may need to expand by up to 5 million hectares by 2030 to meet a rising demand for ethanol biofuels, according to computer models that compared the impact of different economic, social, and policy scenarios on increased ethanol production.

-The recent study found that sugarcane ethanol demand by 2030 would increase by between 17.5 and 34.4 million metric tonnes. This demand could be met without new deforestation by intensifying ranching practices and converting existing Brazilian cattle pastures to sugarcane.

-However, in a move that surprised many experts, President Jair Bolsonaro this month revoked a decree limiting sugarcane cultivation in the Amazon and Pantanal biomes, leaving the decision about how to meet rising ethanol demand in the hands of the sugarcane industry.

-Experts say that even with the end of state regulation, sugarcane expansion into the Amazon and Pantanal is unlikely due to poor agricultural conditions and lack of infrastructure there, along with the industry’s need to maintain its positive environmental reputation in international markets.

David Lapola, an earth-system modeller at the University of Campinas in São Paulo state, not involved in the research, says he’s not surprised by the findings. “Of course, the demand for transport and the policies related to that … will affect the future demand,” he said. However, “the good thing is that they put that in numbers.”

Lapola does point to some uncertainties: ethanol isn’t the only possible product of sugarcane — harvested canes can also, for example, be processed into sugars for use in food — something he says the authors didn’t take into account. So even if Brazil’s domestic demand for ethanol subsides, sugarcane production may grow along with global demand for sugar.

While sugarcane-based biofuels are typically dubbed as renewable, “whether ethanol use actually reduces greenhouse gas emissions depends on how the sugarcane is produced,” explains geoscientist Akenya Alkimim from the Universidade Federal de Vicosa in Minas Gerais, Brazil.

Last year Alkimim reported the results of computer modeling, showing that for every hectare deforested in the Amazon, sugarcane plantations would release 608 tonnes of carbon dioxide into the atmosphere, creating a total “carbon debt” that would take 62 years of biofuel production to payback. So, she asks, “What would be the purpose of switching over to a ‘clean energy’ [renewable biofuel] if it would result in a higher overall carbon debt?”

However, if Brazil meets its rising sugarcane production needs not through new deforestation, but by converting existing pasture to cropland, that would release less than a tenth of the CO₂ and take only six years to repay the carbon debt.

Expansion of sugarcane into existing pasture could still indirectly drive increased carbon emissions if that land-use shift merely displaces cattle from already degraded grazing lands, causing ranchers to deforest elsewhere.

Thankfully, this worst case scenario has not been borne out. Instead, Lapola and colleagues have observed a different sequence of events: cattle ranchers giving up degraded pasture, tend to intensify land use by multiplying the number of cattle grazed per hectare elsewhere, a best use practice known as “increased stocking density” which minimizes new deforestation.

This land use intensification trend is predicted to continue in de Andrade Junior’s models, with increases in stocking density crucial to preventing sugarcane expansion from driving deforestation. “Since the stocking rates in Brazil are very low compared to their potential… higher pasture yields spare land for agriculture expansion without compromising beef and milk production,” said de Andrade Junior.

The repeal came as a surprise for many, as it wasn’t apparently driven by industry pressure. Local industry representatives have previously rejected the idea as an unnecessary risk to the positive environmental reputation of the cane industry, which has historically distanced itself from Amazon deforestation.

In a statement published on the Brazilian Sugarcane Industry Association (UNICA) website, the organisation reaffirmed their commitment to the National Biofuel Policy (RenovaBio), a voluntary initiative that prohibits deforestation and rewards fuel producers that emit less carbon into the atmosphere with “decarbonization credits,” which is set to come into force in 2020.

Experts hope that RenovaBio combined with the current Brazilian Forest Code, which mandates that 80 percent of privately owned land in the Legal Amazon must be conserved, will constrain sugarcane expansion to degraded pasture and other already existing agricultural land, despite the loss of ZAE regulations.