This article was written by UC Davis ARE PhD student Bruno Pimenta.  It is the seventh in a series of excellent articles written by students in my ARE 231 class this fall.

After years of decline, fires in Brazil's Amazon rainforest have surged recently. The drivers of deforestation, deeply rooted in the Brazilian rural sector, have received international media attention. Generally, loggers and land grabbers clear the land and sell it to cattle ranchers. Soybean producers claim they have no linkage to deforestation. However, the country's massive increase in soybean production over the past decades might tell a different story.

From a negligible production in the 1960s, the country's soybean production increased rapidly and constantly since 1970. At the beginning of the last decade, Brazil already produced more soybean than the rest of the world, excluding the United States and Argentina. In 2019, the country became the world's largest producer, surpassing American soybean production. United States soybean production has steadily increased over the years. Nonetheless, in 2020 Brazil produced 135 million tons of soybean, the largest value ever reached by a single country.

But where does all this soy go? What is it used for? Brazil exports most of its production, approximately 65%.  The country represents about 50% of the world's soybean exports, a position that Brazil will keep throughout the decade, a report by the Food and Agriculture Organization of the United Nations (FAO) estimates.  China is the main destination of the country's production, accounting for 85% of the Brazilian soybean' exports.

But why does China import so much soy? Soybean are a versatile product that has many utilities. It is used in the cosmetic, pharmaceutical, and, naturally, food industries. It can also be used to produce biofuels. However, the primary use of soybean is to feed livestock, accounting for 79% of its use in the world, especially due to their relatively low prices and protein-rich nature. Ultimately, when we eat beef, pork, or chicken, we are indirectly eating soy.

To feed a meat-hungry world, Brazilian soybean producers increasingly expanded their cropland. From 240,919 hectares harvested in 1961, soybean farmers harvested 35,881,447 hectares in 2019, an expansion of almost 15,000%. In comparison, the United States harvested an area of 10,928,000 hectares in 1961 and 30,352,150 hectares in 2019, an increase of 177% (FAOSTAT).

For such an expansion to be possible, farmers not only switched from other crops to soybean, but areas previously used by cattle ranchers were converted to soybean production. As discussed a 2020 paper by Assunção and co-authors, cattle ranching is usually a low-technology activity in Brazil. Ranchers expand their livestock numbers by increasing their pasture land. During most of Brazil's history, ranchers dominated the Cerrado, a tropical savannah biome that crosses the country diagonally.

The Cerrado's acidic soil made it unsuitable for agricultural production. However, technology has made it possible for farmers to correct the soil's PH and also use more resistant soybean strains with higher yields. In 1961, Brazil had an average yield of 11,269 hg/ha (hectogram per hectare). At the same time, American producers yielded on average 16,900 hg/ha of soybean. In 2019, both countries had very similar yields, 31,846 hg/ha and 31,890 hg/ha for Brazil and the United States, respectively (FAOSTAT).

Land Use in Brazil

The Brazilian Center-West, a region dominated by the Cerrado biome, is the country's largest soybean producer, followed by the South region. Now, more than 44% of the Cerrado is devoted to agriculture. As soybean producers expand their activity, they push cattle ranchers northwards towards the Amazon. An inevitable consequence of this agricultural frontier expansion is deforestation, reflected by the increase in pasture in the north, as the map above shows.

Between 2019 and 2020, Brazil registered the two years of highest deforestation ever recorded. The international community pressure on the Brazilian government to curb deforestation and the ever-increasing demand for cheap soybean are two forces that will determine the future of the world's most iconic rainforest. 

You can generate the soybean production charts in this article using this R code.