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Chapada dos Guimarães has a national park to preserve some of the Cerrado biome. Photo: Alessandra Marques da Silva Thompson, Wikimedia Commons, CC 4.0

World’s most biodiverse savannah soon to become a carbon emitter

Greed threatens the Brazilian Cerrado, evidencing short-sightedness from decision-makers.
Greed threatens the Brazilian Cerrado, evidencing short-sightedness from decision-makers.

The Amazon is not the most endangered biome in Brazil. It’s got a neighbour with wooded grasslands that nest species like the golden trumpet tree. Its bright yellow flowers bloom during the Brazilian winter and its thick bark withstands scorching summers—and, with a 1961 decree by then-president Jânio Quadros, it is also a symbol of Brazil.

The competition with soy and cattle for space in the Brazilian savannah—or Cerrado—has, however, been harsh on golden trumpet trees. As it has been on animal species like the giant armadillo (the biggest and rarest armadillo in the world) and the tapir, South America’s largest mammal. Forced to fight chainsaws and tractors, they are not winning. 

Taking up almost a quarter of the Brazilian territory, the Cerrado seconds only the Amazon in extension. It feeds most of the main river basins in the country and is the world’s most biodiverse savannah. Yet, it is under severe strain. 

The maned wolf is one of the most known as a typical species in the Cerrado. It is the largest canine in South America and it’s classified as near threatened with extinction by the IUCN’s Red List of Threatened Species. Photo: Jonathan Wilkins, Wikimedia Commons, CC 3.0

From sink to emitter

Deforestation is driving climate change and threatens water supply throughout Brazil. Besides harming biodiversity, this could turn the biome from a carbon sink to emitter in three decades. 

Its intensive land use can speed up climate change processes, unleashing a vicious circle that harms biodiversity and the economy in Brazil. 

Mercedes Bustamante, professor at the University of Brasília, explains that the Cerrado currently works as a carbon sink: it absorbs more carbon dioxide in the rainy season than it emits during the dry period. Higher mean temperatures are likely to disrupt this balance. 

“Climate change can affect the rainy season by decreasing precipitation at the same time it increases the length of the dry season. If this happens, the Cerrado can go from a sink to a carbon dioxide emitter,” she says. A longer dry season also means more fires in the biome, limiting the vegetation’s capacity to absorb carbon even further.

The more the Cerrado becomes pastureland, the more land surface temperature rises—and less water flows back into the atmosphere. Extreme events such as changes in humidity and more erratic weather patterns are already putting the biome under pressure, Bustamante said.

“If the Cerrado areas become less suitable to agriculture, it means an increased pressure over neighbouring biomes, especially the Amazon,” says the researcher, who co-coordinated the chapter on land uses for the latest IPCC report

It is always about the economy 

Raoni Rajão, associate professor of Environmental Management at the Federal University of Minas Gerais, says that one of the greatest problems is that landowners privatize profits and share losses, largely disrespecting environmental regulation. 

An example is the existence of more than three thousand private properties located in conservation areas of the Cerrado that should be wholly protected from economic activities of any kind. The area, according to WWF-Brazil, takes more than 11 thousand square kilometers—larger than countries like Cyprus or Lebanon.

Such disregard for the law is true even if the value of ecosystem services the Cerrado can provide is more than 10 times what agribusiness can obtain in the same area. A hectare of undisturbed Cerrado can generate over US$3,300 in natural services such as erosion control, water regulation and pollination—besides the absorption of greenhouse gases. 

On the other hand, soy producers get US$300 from that same area. And collective losses will definitely be much greater than that if the Cerrado begins to emit more carbon than it stocks in a few years. 

Mercedes Bustamante observes that if this happens, it will mean less carbon trapped in the soil and by plants themselves. “Large portions of vegetation will suffer because of this imbalance and will fall apart faster than they would otherwise,” she says.

Calliandra, also known as flor-do-cerrado (Cerrado flower) is one of the symbols of the biome (free image)

The problem, Rajão sees, is also symbolic. The Cerrado is not as widely known as the Amazon and, even in Brazil, the area is not as valued as it should be. “Burning the Amazon is like setting Da Vinci’s Monalisa on fire or melting the Eiffel Tower to use its metal for other purposes. This collective sense of violence just doesn’t embrace the Cerrado,” he says. 

Part of the agribusiness sector is starting to realize that the depletion of the biome is not only dire for biodiversity but also bad for business. Rajão says the sector used to be monolithic in its decisions, but now local producers and exporters are split. Agribusiness uses 40% of the biome, according to the WWF-Brazil.

Representatives from the Brazilian agricultural sector such as the Brazilian Confederation for Agriculture and Farming (CNA) and the Association of Soy and Corn Producers of Mato Grosso (Aprosoja) weren’t available for comment by the time this piece was edited. 

“Exporters are being pressured, especially by European markets, to be more sustainable. Producers are not fully engaging in the conversation—maybe because they haven’t been penalized for real yet”, Rajão adds.