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Soy made the Cerrado a breadbasket; climate change may end that

  • The Brazilian Cerrado is a vast tropical savanna covering over 20% of the nation’s landmass. More than half the Cerrado’s native vegetation — much of it biodiverse dry forest — has been converted to agribusiness, turning it into a breadbasket for Brazil and a key source of soy for China, the EU and other international markets.
  • Brazilian soy cultivation is set to expand by 12 million hectares between 2021 and 2050, with the vast majority of that expansion happening in the Cerrado and especially on its agricultural frontier — a four-state region known as Matopiba.
  • However, the Matopiba region (consisting of Maranhão, Tocantins, Piauí and Bahia states) is more vulnerable to climate change than other parts of Brazil. Researchers say global warming on the savanna is also worsened by the conversion of native vegetation to croplands and pastures.
  • Extensive conversion of native vegetation (which holds moisture in roots deep underground) into a soy monocrop (which stores little water) is becoming a major problem, as little Cerrado soy is currently irrigated. Scientists argue that the conservation of native vegetation must be actively pursued to save the Cerrado agricultural frontier.
Bare ground in fields along the BR-020 in August 2019 awaits the planting of Brazil’s most lucrative export — soybeans. Image by Sarah Sax / Mongabay.

A Mongabay team, Sarah Sax and Maurício Angelo, recently traveled to the Brazilian Cerrado to report on the impacts of booming agribusiness on the savanna environment and on the traditional people living there. This is the sixth story in a series telling what they found there.

WESTERN BAHIA, Brazil — Drive seven hours north on the BR-020 from Brasília, Brazil’s capital city, to the fast-growing agro-industrial city of Luis Eduardo Magalhães in Western Bahia state and you notice two things. The first is how new and straight as an arrow the well-paved road becomes as you cross from Goias state to Western Bahia — a sure sign of significant recent infrastructure investments to spur on agribusiness there.

The second thing you notice if traveling in August as we were, is how as soon as you enter Western Bahia, all vegetation disappears, giving way to endless brown, seemingly barren, fields cooking in the sun — most waiting to be planted with the cash crop that has transformed what was once one of Brazil’s most economically neglected regions into an agribusiness powerhouse; the Cerrado biome’s most valuable export commodity is soy.

Since the mid-1970’s, Brazil has transformed itself from a net food importer to a globally essential food exporter. But this agricultural revolution has come at a high cost, both for the Amazon biome and also for the Cerrado, the world’s most biodiverse savanna, containing 5% of all species on earth, including more than 10,000 plant species, and over 900 bird and 300 mammal species.

The Cerrado biome covers 2 million square kilometers (772,204 square miles). However, half the savanna’s native vegetation — mostly dry forest and scrubby grasslands — is gone, converted to crops (planted primarily with soy, but also corn and cotton, oil palm and eucalyptus monocultures), as well as cattle pasture, to the serious detriment of biodiversity, water availability, and traditional peoples’ livelihoods and lives.

Now, scientists are worried about how these changes may affect the future of the biome – one that already is more susceptible to climate change, and especially drought, than other parts of Brazil.

A Brazilian soy plantation in the Cerrado. Image by Alicia Prager / Mongabay.

An agricultural boom headed toward bust?

With the planet’s human population already topping 7.8 billion people, and the demand for meat soaring in China and Asia, developing countries are competing to keep up with the swelling international food demand — an endeavor especially true for Brazil and its large-scale soy and meat producers.

Brazil today is focusing its surging agricultural expansion primarily on one region, staking the country’s economic future on the northern Cerrado, a four-state area dubbed “Matopiba” by producers. But that region, composed of the states of Maranhão, Tocantins, Piauí and Bahia has an Achilles heel — it has always been susceptible to drought. And in recent years, hot dry conditions there have worsened, partly due to intensifying climate change, and also due to the loss of drought-resistant, water-holding, native vegetation. Experts now fear that the Cerrado’s agricultural revolution — already vulnerable due to a lack of irrigation infrastructure — could ultimately be short-lived.

“We’ve got warming all over the planet, but Matopiba is particularly delicate because it’s agriculture is rain-fed,” explains Michael Coe, an earth system scientist at the Woods Hole Research Center in Massachusetts, USA. Crops “just barely make it right now… and [the Cerrado is] switching to a much drier climate,” he says. “It’s going to have a heck of a problem achieving high yields with rain-fed agriculture in a lot of areas.”

According to a 2013 report by the Brazilian Panel on Climate Change, average temperatures in Brazil could be 3º-6º Celsius (5.4º-10.8º Fahrenheit) higher by 2100 than at the end of the 20th century, while rainfall in the north and northeast of the country could diminish by up to 40%. Those extreme temperatures, along with relentless drought in an extended dry season, could bring financial ruin to Cerrado agribusiness.

Soy expansion in Matopiba has been rapid over the last decade, as has the loss of native vegetation. Image by Sarah Sax / Mongabay.

Soy expansion by the numbers

Brazil’s soy expansion has been rapid. Production began steadily rising in the 1970s, but skyrocketed recently, more than doubling in the last decade, with the versatile bean feeding Brazil’s national needs, as well as meeting international demand. Brazilian soy today is used as feed for millions of pigs in China and for chickens in the European Union. This extraordinary agribusiness boom also led to massive deforestation and other environmental harm in both the Amazon and Cerrado.

This year, Brazil is set to surpass the U.S. and become the world’s largest soy producer, growing a record-breaking 125 million metric tons on 36.9 million hectares (91 million acres). This prodigious output can partially be attributed to crop intensification on lands already in production — much of it in the southern Cerrado. But the most recent wave of vegetation clearing has shifted north to Matopiba, a dryer area.

And this soy boom is set to continue. According to one study, Brazilian soy lands are expected to expand by more than 12 million hectares (29.7 million acres) between 2021 and 2050, with almost 11 million hectares (27.2 million acres) newly planted in the Cerrado alone. Of that, 86% is projected for Matopiba. This astronomical growth will also require major deforestation, meaning much less native vegetation to hold moisture in deep roots, which will add to drought intensification, even as climate change worsens, bringing less rain and more heat.

The Cerrado does have significant aquifers, with the biome long dubbed Brazil’s “birthplace of waters,” but even that river and underground supply seems unlikely to be able to sustain agribusiness in a drying world, according to experts.

“There’s pretty good evidence that deforestation, taking out the native vegetation, decreases the length of the wet season,” says Woods Hole researcher Coe. “That’s why we pretty much always argue the first thing we should do is stop deforesting, because that’s just exacerbating the problem. But savanna deforestation is showing no sign of slowing.

The Cerrado’s ability to feed the Brazilian people and the world is dependent on the savanna’s rivers and aquifers which are now seriously threatened by deepening climate change and expanding agribusiness. Image by Sarah Sax / Mongabay.

Western Bahia, the coming drought?

The municipality of Luis Eduardo Magalhães in Western Bahia offers a prime example of how soy has transformed the Cerrado’s land, economy and its people. Since 2000, the city’s population has grown more than fourfold to 83,000 people, making it one of Brazil’s fastest growing urban centers.

Today, Luís Eduardo Magalhães has the fourth highest GDP per capita in Bahia state, and ranks 20th in Brazil’s GDP of Agribusiness. But growth has its downside: public services, including sanitation and crime prevention, have failed to keep up. Many new arrivals from the countryside, lacking specialized skills, have been unable to get good jobs or gain access to the highly mechanized industrial agribusiness economy. So they remain poor, living in impoverished neighborhoods marred by drug trafficking and gang violence.

Still, the city remains a hub for Western Bahia soy production, a region that has seen as much agricultural expansion as the other three Matopiba states combined — equivalent to an increase of 352% since 1985.

“Bahia [equals] what the other three states plant together, both in [planted] area and in production; we are at least 15 years ahead,” says Luiz Shalke, a spokesperson for the Association of Farmers and Irrigators of Bahia (AIBA). Bahia had a head start, he explains: “We began in the 80’s; they [the states of Maranhão, Tocantins, and Piauí] started in 95, [and] after the 2000s.” The association represents 1,300 Bahia producers, primarily in the 9 municipalities of the western-most part of the state, where, according to Shalke, “99.9% of all soy producers are” located These municipalities also have some of the highest deforestation rates in Brazil.

Importantly, Western Bahia differs from the other areas in terms of its use of irrigation, which relied on just 9 center pivots in 1985, growing to 1,550 center pivots in 2016. However, the majority of soy production is still rain dependent, which is an alarming fact to scientists like Coe, but not to AIBA.

Schalke and other Cerrado farmers interviewed by Mongabay in 2019 don’t agree that climate change is currently impacting, or will impact, future production, except possibly regarding the availability of water for irrigation. “Based on our data, we’ve had similar moments of bad rain and good rain [in the past]. It’s been a very cyclical climate these past 80 years,” says Schalke. “Climate change has not affected our production; we had problems with drought because we were not prepared to go through this normal period of dryness, but the average production is now good.”

Croplands make heavy demands on Cerrado water. Pictured here is a large-scale irrigation system. Conservationists are concerned about the draining of aquifers due to drought and agribusiness growth. Image by Flávia Milhorance / Mongabay.

This statement flies in the face of many recent Cerrado scientific studies, especially in Matopiba. “We are in a rapid shift. The difference in climate [here] in the next couple of decades will be enormous,” Coe states. “Every indication shows that there is going to be a very rapid, and one directional, change towards drier. And this is not 2100 we are talking about, this is 2030.”

Climate modeling shows that clearing native vegetation in the Cerrado increases climatic variability in part by decreasing the amount of water recycled to the atmosphere. Research has found that for every million hectares of Cerrado converted to croplands, dry season evapotranspiration decreased by 1.7 km3. For example, in 2013, cropland areas recycled 3% less water than they would have had they been cloaked in native vegetation.

A different University of Brasilia study linked native vegetation clearing to an 8.4% drop in annual Cerrado rainfall over the last three decades. Considering that the Cerrado currently feeds 8 out of the 12 hydrological regions of Brazil, that statistic is deeply worrisome.

But there are larger trends that scientists are most concerned about.What we are seeing in Matopiba is that the climate has already been changing towards a drier climate — a longer dry season and more frequent drought,” says Coe. “That’s where it’s headed in the next couple of decades. The new extreme is becoming the norm.”

A recent study by the Brazilian Agricultural Research Corporation, utilizing UN Intergovernmental Panel on Climate Change (IPCC) global warming scenarios, found that the amount of land suitable to soy production in Brazil by 2040 could be reduced by up to 39%. And according to a 2017 report by IPAM, the Amazon Environmental Research Institute, a scientific, non-governmental, non-partisan and non-profit organization, more than a quarter of all land in Matopiba is already in moderate to high-risk productive zones due to climate and soil.

Although AIBA may not be concerned about deepening climate change, they are concerned about water availability, especially as the use of irrigation continues to expand. “Lack of water due to climate change does affect us,” Schalke said. “Everyone says there is a lot of water in the Urucuia Aquifer, but no one has ever stopped to analyze it. We need to understand in order not to have a problem in the future.”

AIBA, in association with Brazilian universities, the government of Bahia and the University of Nebraska, is studying the water potential of Western Bahia to verify capacity and whether water may be lacking for planting and irrigation in future. According to producers, there are still opportunities to advance the use of irrigation in Bahia; but the implementation of that infrastructure won’t be inexpensive, while escalating climate change may deplete aquifers and outpace short-term irrigation fixes.

The Cerrado’s scrubby grasslands and dry forest don’t appear particularly biodiverse at a glance, but the Brazilian savanna harbors an estimated 5% of all species on the planet. Image by Sarah Sax / Mongabay.

A path forward: land use intensification

As scientists worry about the impact clearing new land could have on Cerrado rainfall and regional climate stability, many experts are pointing out that soy production could easily continue increasing, without ever clearing another hectare of native vegetation.

According to a paper published last year by Lisa Rausch at the University of Madison Wisconsin and colleagues, in 2015 there were 23 million hectares (57 million acres) of already cleared land in the Cerrado considered highly suitable for soy, and another 15 million hectares (37 million acres) classified as potentially suitable. Soy production could double or even triple if all that already cleared land was utilized, without any additional native vegetation conversion.

Donald Sawyer, senior advisor at the Institute for Society, Population and Nature (ISPN), an NGO that has been working intensively in the Cerrado since the 1990s, asserts that the solution to the Cerrado conundrum lies in working with already degraded land, and strengthening alternative systems of production in the biome — shifting to scaled-down agricultural systems, including family farming, that have received far less attention, money and public support than the highly industrialized and mechanized model.

“I’m really worried that family farming will go extinct,” he told Mongabay. “Small farmers can live in complex mosaics.” That system is “not perfect, but it’s better than nothing. Those [small farm, multi-crop] mosaics can store carbon better than soybeans or pasture can, and increase infiltration of water into the ground.”

Mosaics, patches of different kinds of habitat types (including forests, riparian buffers, and agricultural lands), are also important in preserving remaining Cerrado biodiversity, which is seriously threatened by climate change and expanding agribusiness.

While most people understand the importance of the Amazon, maybe due to the grandeur of the rainforest, Sawyer points out that the importance of the vast and unique diversity found in the Cerrado, with its dry forests and grasslands, is often underappreciated.

That diversity may also have value above and beyond its intrinsic existence; the Cerrado biome may have much to teach us, Sawyer explains: “Cerrado biodiversity [could] be of strategic importance to the world because of its natural characteristics of resilience to heat and drought,” conditions that will surely worsen around the world in coming years. A closely studied Cerrado, he says, could yield up secrets useful for surviving and thriving in a much hotter, dryer world.

“The tropical rainforest is very species rich and might hold the key to cancer,” Sawyer concludes, “but specifically, in regard to these genetic [survival] risks, the Cerrado can be of strategic value in the context of [our adapting to] global warming.”

Banner image caption: Soy is currently king in the Brazilian Cerrado, but intensifying heat and drought due to climate change and deforestation could bring the agribusiness boom to an end.  Image by Flávia Milhorance / Mongabay.

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