Climate change is already causing problems for Brazilian agriculture. And they are expected to increase considerably in the coming years.
Up to 2019, about 28% of the agricultural area in the transition region between the Amazon and the cerrado —which concentrates half of the national agricultural production— it had been affected and was outside a climate zone considered ideal.
Most of the impacts are in regions of agrarian expansion recent, as the southeast of Goiás and Matopiba (acronym for Maranhão, Tocantins, Piauí and Bahia).
For 2030, the projection is that until
% of this area leaves the ideal zone. Up to 2060, it is estimated that the percentage will rise to 74%.
The data come from the study “The Climatic Limit for Agriculture in Brazil”, published on Thursday (11) in the journal Nature Climate Change, by researchers at the Woodwell Climate Research Center, at Ipam (Institute for Environmental Research from the Amazon), from the universities of California and Richmond, from Unemat (University of the State of Mato Grosso) and from Ufra (Federal Rural University of the Amazon).
Scientists took into account precipitation data and droughts, important factors considering that, according to the survey, about 51% of the agriculture carried out in the observed area depends on rain. The climatic conditions in the 1970 decade, when the occupation of the Center-West for agricultural use intensified, were taken as a reference point.
The study concentrated in the following states: Mato Grosso, Goiás, Maranhão, Tocantins, Piauí and Bahia.
Three questions guided the scientists. Have recent droughts influenced the pace of intensification or de-intensification of agriculture or crops? Has the recent expansion of activity occurred in areas vulnerable to climate change? To what extent has the climate crisis already affected the possibility of production and what is the projection for the near future?
“We have seen that the agricultural areas we are currently occupying are, climatically speaking, marginal, they are suboptimal” , says Ludmila Rattis, a researcher at the Woodwell Climate Research Center and at Ipam, one of the authors of the research. “And this is putting soy and corn productivity at risk.”
According to Rattis, the agricultural frontier has moved towards a drier area (with higher temperatures not offset by the amount of rain), which leads to a greater possibility of hydric stress for the plantations.
In recent decades, Brazilian agricultural production has been growing, but the pace, warn the researchers, is hampered by drought events. “If you look closely, you can see that, in recent years, when producers lose, they lose a lot more than they used to. And when they win, they earn less.”
In other words, they are almost silent losses, year after year, says Rattis. “It’s not that the person will arrive and there won’t be rain, soil, there won’t be anything. The production capacity will be lost little by little.”
Currently, the country is experiencing a high situation of prices in consumer items caused, among other reasons, by losses in the fields caused by a prolonged drought and also by frost.
According to the specialist, the areas with cultivation from the decade of 1970 were occupied by plants adapted to the climate scenario at that time (which was perfected with the help of agricultural technology). Areas that now, as mentioned above, are significantly warmer and drier.
Looking only at the rainfall, scientists saw that, in areas with a decrease in average precipitation, there is also a lower probability of an area being used for more than one harvest per season.
“We are not managing to harvest and off-season. Much of the profit is in being able to do two harvests in the same planting window”, he says Rattis.
According to the article, the Brazilian government aims its expansion of cultivation exactly in areas with more climatic risks, but without taking them into account. “Brazil’s agricultural sector will likely face increased crop losses from droughts, heat waves and a prolonged dry season,” warn the authors.
The recent report by the IPCC (Intergovernmental Panel on Climate Change) ) points to projections of increased droughts in the North, Midwest, Southeast and part of the Northeast for the middle of the century.
But there are still ways to minimize the problems. Investing in low-carbon agricultural techniques and genetic alterations to adapt crops to the new climate reality are options.
“Brazil is an agricultural power thanks to the favorable climate and a lot of scientific research. here thanks to the Amazon that produces rain and the cerrado that absorbs water and supplies all the mines we have”, says Rattis.
The problem is that both biomes have shown high rates of destruction. The Amazon, in recent years, has been devastated by more than thousand km², the highest values in the decade. The cerrado, on the other hand, with about half the size of the Amazon biome, has a level of deforestation not very far away.
“We need to stop deforestation because nature has not read the Forest Code and does not know how to differentiate between legal deforestation and illegal”, summarizes the researcher from Ipam. “And keep investing in research. If we keep destroying and not funding science, it will be very difficult to plant.”