The most egregious example is probably Brazil’s namesake nut. Some Brazil nuts are harvested in Brazil, but then sold to Bolivia and Peru, which shell and package them. These nuts are later exported to Europe — or sometimes even back to Brazil.

Brazil’s stock of deforested land in the Amazon is double the size of California, and a lot of it remains idle or underutilized. While cattle ranching remains one of the more lucrative uses, experts say nuts, cacao, exotic fruits and coffee are all part of an untapped forestry system that, paired with forest plantations and more productive cattle ranching, could provide more sustainable economic alternatives, if anyone pushed for them.

But the economy of the Amazon, simply put, has never been a priority for the rest of Brazil, which has competing infrastructure and development needs, Veríssimo said. It is often an afterthought for national leaders, many of whom have never visited or don’t grasp its complexity and opportunity.

The Amazon holds at least a third of the world’s remaining tropical forests. Some sources put it at more like half. Its rains supply farms and cities across South America. That makes the Brazilian presidential election one of the most important in the world for anyone who cares about the planet.

The 20 million voters who live in the Brazilian Amazon will vote in an election in which the two candidates were separated in the first round by roughly 2.2 million votes. That no major party in Brazil has yet figured out a sustainable way to persuade many of these voters to preserve the environment where they live is now poised to have consequences for everyone.