Rainforest Payback: How deforestation fails agriculture in the Amazon
Brazilian soybean and maize agrobusiness lost more than 1 billion US dollars due to changes in rainfall caused by Amazon deforestation between 2006 and 2019, according to a new study by Rainforest Foundation Norway and Minas Gerais Federal University in Brazil.
The advance of Brazilian agricultural production to the detriment of the largest rainforest on the planet is taking a heavy toll not only on the environment but also on agribusiness.
Researchers from Minas Gerais Federal University (UFMG) warn that climate changes caused by deforestation may be leading these farmers to what they call "agro-suicide" – when the impact of deforestation affects rainfall regimes to the point of making harvesting impossible.
Economic argument aims to convince agribusiness
Anders Krogh, an expert at Rainforest Foundation Norway, joined the researchers from UFMG on a field trip to the Brazilian state of Pará to interview the farmers featured in this article.
Krogh argues that the research findings show a new argument for preserving the Amazon, this time not just environmental, but economic This can be a strong argument for rural producers to stop deforesting.
"Between 80 and 90% of deforestation in the Amazon comes from agricultural expansion. We have to use all the tools we have to save this biome, and proving that less forest means less rain can convince the agricultural sector and local farmers that protecting the rainforest is really in their self-interest", says Krogh.
Rainy season delayed by 76 days
The UFMG study reveals that climate change caused by the loss of forests has already delayed the rainy season by up to 76 days in some regions of the Brazilian Amazon, directly affecting the plans of farmers who were used to harvesting twice a year. As a result, these farmers are feeling the effects of climate change where it hurts the most, in their pockets. The researchers calculate losses for soybean and corn producers of more than 1 billion US dollars over 14 years. The research is supported by Rainforest Foundation Norway.
The study cites that 30% of the rainfall in the Amazon comes from water that evaporates into the atmosphere from the forest. The paths this moisture takes to reach the Andes Mountains, as well as regions in the south and southeast of Brazil, are called "flying rivers". Without the forest, these "rivers" dry up and the effect can be devastating, explains forest engineer Argemiro Teixeira, a researcher at UFMG's Remote Sensing Center and one of the authors of the study.
"On average, regions that have more than 80% of their area deforested show a delay in rainfall of two weeks every five years. On the other hand, in regions where 80% of the forest is preserved, as demanded by the Brazilian legislation for the Amazon biome, this same delay occurs every 20 years. So the climatic risk to crop production is four times bigger in deforested areas," says Teixeira.
Rain delays cause massive economic losses
Rain being delayed by two weeks may not seem like much, but for agriculture, it can mean millions of dollars in losses. To optimize the use of the soil, farmers usually harvest two crops a year. The first is soy, which runs from December to March, followed by maize. With the delay in the rains, the window for maize production is so short that the second harvesting becomes unfeasible.
"If the rain doesn't start, the farmer will postpone planting, so for soybeans he can plant when there is rain. The problem is that the photoperiod (Ed. the period of time that the plants receive light each day) is already decreasing by the time the farmer puts the maize in the field. The amount of rain has also decreased. So this puts stress on the plant and it can't produce enough," explains Teixeira, who also cites the figures calculated for economic losses.
"Deforestation has caused a loss in the Amazon of more than 760 million dollars for soybean production and another 270 million dollars for corn production between 2006 and 2019," he adds.
Farmers confirm losses, but deny climate change
The research carried out by UFMG's Remote Sensing Centre included interviews with 20 agricultural farmers organizations, as well as 13 farmers. They reported net revenue losses of between 10 to 40 percent in those years affected by the atmospheric phenomena El Niño and La Niña - altering the temperature of ocean waters and either causing the onset of the rainy season in the Amazon to be delayed or to be short and intense. Even though they experience the effects of changes in the rainfall regime in practice, many farmers resist admitting that there is a link between deforestation and climate change.
"They don't say they are adapting to the climate, but they are changing the way they produce and if they don't change their production systems, they won't be able to produce. This is very important to us and supports the data we collected during our research," says Sônia Carvalho, a professor at the Department of Cartography at UFMG and one of the authors of the study.
For Vinicius Scaramussa, a 37-year-old farmer who owns a 3,000-hectare land that produces soybeans and maize on an area that also rotates with cattle ranching, the variation in rainfall puts the second harvest under threat.
"We can't control the rain, the sun, anything. So I say that we are
products of the environment. The trend for the next harvest is La Niña,
when the rainfall in our region increases. So what do we do? I've
already bought an extra fungicide as a precaution if it rains too much
so that my crop doesn't get sick," says Scaramussa.
Scaramussa's farm is in Paragominas, in the southeast of the state of Pará. The researchers visited his and three other rural properties to understand what actions the owners have taken in recent years to adapt to changes in the rainfall regime.
Irrigation systems replace rainfall
"We chose Paragominas because it is an old agricultural frontier, which began with the timber cycle. Then there was livestock farming and now agriculture," says Professor Sônia Carvalho, pointing out that farmers in the region have started to adapt to changes to reduce the effects of rainfall variations, like introducing irrigation. "They are highly susceptible to changes in the climate. Without being able to have more resilient systems, they showed us that they couldn't be doing activities such as livestock farming, ” she says.
To guarantee production regardless of rainfall variations, the farmer Gilberto Maraschin chose to invest R$10 million to implement an irrigation system on 700 hectares of his farm in Paragominas.
“Technology has helped us improve our harvest a lot. But when the weather says 'no, I'm not going to rain for a week', then there's nothing to do about it", says Maraschin, justifying the investment in the irrigation system.
Higher temperatures where the forest is gone
Another consequence of accelerated deforestation in the Amazon has been an increase in temperature. According to the UFMG study, deforested areas had an average temperature increase of 15% compared to intact forest areas.
"The second effect of deforestation is on temperature, because when you remove the vegetation, deforestation decreases what we call the albedo effect, which is how much of the energy coming from the sun’s rays that the surface reflects. So if it reflects less, as it does when the vegetation cover is removed, the air temperature gets warmer," explains Teixeira.
Farmer Murilo Zancaner shows us an area on his farm that has been preserved for 15 years and naturally reforested.
"Here we have a place near the forest where we can see that the rain comes more into the farm. It seems to draw more water. I don't know if it's because of the forest, but it rains more here than in the other plots”, says Zancaner.
The limits of technology
After deducting the production costs, the researchers calculated that the farmers suffered revenue losses of 10% from soy production due to deforestation-induced climate change. According to the study, the maize, with more than 80% of its production happening in the second harvest of the year, suffered losses of 20%. Thus, many farmers rely on technological innovations to continue producing under the more extreme weather conditions.
"We have people who invest in knowledge and technology to bring new farming methods adapted to our region. Paragominas could be a reference for production for other regions in Brazil. Paragominas is among the ten cities with the highest soy production in the country and is a showcase in livestock farming, all thanks to investment in knowledge and adaptation of the resources we have," says Renata Salatini, one of the farmers visited by the UFMG researchers.
Despite recognizing the technological advances within the field, the study warns that there could be a climate point of no return. In these cases, not even the most advanced technology can make soy and maize production in the Amazon profitable.
"Not all producers have access to technology. For example, only 10% of agricultural production in the Amazon is artificially irrigated, which is very little. In other words, 90% of producers depend on rainfall to produce. For there to be irrigation, there needs to be water. In some places in the Amazon there is already conflict over the use of water. Therefore, we usually say that the best strategy today, or the best “technological advance”, for production is forest conservation," warns Teixeira.