Over the last 25 years, the Brazilian Amazon lost an area of forest about the size of Germany. About 80% of that ended up as pasture or abandoned pasture.

Most deforestation took place on the Amazon’s southern and eastern edges in Para, Matto Grosso, and Rondonia. In a fascinating study published in the latest issue of Agricultural Economics, Benoit Mertens from CIFOR and four colleagues from CIRAD and EMBRAPA use satellite images and economic data to analyze one of Para’s main deforestation hotspots, the municipality of Sao Felix de Xingu.

Back in 1980, Sao Felix de Xingu had only 22,000 head of cattle. Today it has almost one million. Each new animal has meant about one less hectare of forest.

Large cattle ranches, or fazendas, cleared about 35% of the forest lost between 1986 and 1999. New roads connected south Para with northeast and southeast Brazil, giving south Para’s meat and dairy producers access to major urban markets. To supply those markets investors built large refrigerated meatpacking plants, which have bought increasing numbers of cattle from the fazendas. The only thing that has kept the large ranches from growing even faster is that two years ago the government prohibited people from shipping beef products from Para to the southeast because of foot and mouth disease.

During the same period, small-scale ranchers in government colonization projects accounted for 42% of forest loss. These ranchers originally sold their cattle to municipal slaughterhouses that catered to nearby towns. However, the government closed many of those slaughterhouses for failing to comply with health regulations. Now the small ranchers mostly sell calves to the fazendas, who fatten them for sale to the big factories. The smaller ranchers also sell milk to modern dairy plants attracted to the area by public investment in electricity, roads, and credit.

The remaining 23% of pasture expansion came from medium-sized ranches and small ranchers outside colonization projects.

Conservation areas and indigenous reserves suffered less deforestation than other forests, although there was a lot of logging there. Steep slopes and wide rivers also helped protect certain forests.

The authors’ analysis makes it clear though that protected areas were by no means the only policy that influenced what happened to the forest. Transportation investments, agricultural credit, land reform, energy projects, and health and sanitary regulations were just as important.