Sugarcane expansion areas may suffer from impact of climate change

Water shortages and disputes will tend to hinder irrigation during dry season, according to study by Brazilian researchers.

By Elton Alisson  |  Agência FAPESP – The areas used to expand sugarcane growing in Brazil, ranging from the far west of São Paulo State to the south of Goiás State, may suffer from the impact of climate change predicted in these regions, such as rising temperatures and longer periods of drought. This forecast is part of a research project conducted at the University of Campinas (UNICAMP) in São Paulo State.

The main findings from the project, which was supported by FAPESP, were published in August by Editora Unicamp in a book entitled Planejamento da produção de cana-de-açúcar no contexto das mudanças climáticas globais (“The planning of sugarcane production in the context of global climate change”, available only in Portuguese).

“The study involved researchers not only in the agricultural area but also in population studies, health, science and technology policy, genetic engineering and science popularization, since climate change is an issue that must be addressed in a multidisciplinary and interdisciplinary manner,” said Jurandir Zullo Junior, a researcher at UNICAMP’s Center for Meteorological & Climate Research Applied to Agriculture (CEPAGRI) and principal investigator for the project.

In recent years, the researchers at CEPAGRI, in collaboration with colleagues at the Brazilian Agricultural Research Corporation (EMBRAPA), the National Space Research Institute (INPE) and the University of São Paulo (USP), have produced scenarios for the possible impacts of climate change on Brazilian agriculture, particularly such crops as coffee, corn and soybeans.

In the project supported by FAPESP, they set out to study scenarios for sugarcane, given the widespread interest in extending the area used to grow the crop in Brazil in order to meet demand for fuel ethanol. “Sugarcane has always been the only Brazilian crop that offers advantages in a climate change scenario. We therefore decided to test this hypothesis by means of scenarios involving not only the agricultural sector but also other areas, with a view to producing outcomes useful to public policy decision makers for adaptation of the sugar and ethanol industry to climate change in Brazil,” Zullo told Agência FAPESP.

The researchers estimated the possible impacts of climate change on sugarcane yields in three areas: Ribeirão Preto, a traditional sugarcane-growing region; the far west of São Paulo; and southern Goiás. All three are considered suitable for expansion of sugarcane cultivation.

According to Zullo, the amount of sugarcane produced in these expansion areas has risen compared with other crops, especially in areas previously used for livestock production.

“We detected an increase in sugarcane production in these areas, especially southern Goiás,” he said. “Municipal governments have strongly encouraged this expansion because it’s a source of significant amounts of tax revenue for the cities concerned.”

Simulations using the scenarios indicated that the traditional sugarcane-growing region should not face problems related to climate change.

The main problems with this region, according to the researchers, are production planning and shipping. “There are sugarcane areas in the region that contain 14 mills producing ethanol and competing for sales in the ethanol market. This is negative inasmuch as it drives down ethanol prices,” Zullo said.

Areas selected for sugarcane expansion will be affected by climate change because they will require so-called “salvation irrigation” during the dry season. “Considering the current water shortages and disputes in Brazil, these areas will face the challenge of ensuring water for irrigation of sugarcane and other crops while at the same time maintaining the water supply to homes and factories,” Zullo said.

The researchers also noted that sugarcane genetic improvement programs have failed to develop varieties better adapted to climate change.

“The genetic improvement programs have focused on the near term, addressing such issues as yield, pest resistance, or adaptation of varieties to new areas for cultivation. However, we were unable to detect a concern with long-term issues such as developing a variety adapted to water and heat stresses,” Zullo said.

Planejamento da produção de cana-de-açúcar no contexto das mudanças climáticas globais
Editors: Jurandir Zullo Junior, André Furtado and Claudia Castellanos Pfeiffer
Publication: 2017
Price: R$68.00
Pages: 392
Language: Portuguese
More information: www.editoraunicamp.com.br/produto_detalhe.asp?id=1114