Mr. Bolsonaro felt compelled to dispatch the military to put out blazes — but also rejected millions in aid pledged by the Group of 7 nations to help. Here is a sample of his long history of remarks on Indigenous protections and the environment, which range from dismissive to caustic and crude.

On Environmental Crimes

Mr. Bolsonaro has often criticized agencies that enforce environmental laws, and called fines for environmental crimes an “industry” that needs to be abolished.

Last week, in a video broadcast live on Facebook, he chided agents from IBAMA, the main federal agency tasked with enforcing environmental laws, for issuing too many fines.

“The guy would arrive with a pen in each hand, applying astronomical fines … We put an end to that.”

The agency’s enforcement actions decreased by 20 percent during the first six months of this year, compared with the same period in 2018.

Early last week, Mr. Bolsonaro said he suspected the fires had been set by pro-conservation N.G.O.s, in an effort to undermine him. He provided no evidence to back up the assertion.

“This is the war we face … We are going to do whatever it takes to contain these criminal fires.”

On Conservation

Mr. Bolsonaro has been dismissive of the value of conservation efforts, arguing that environmental regulations should be relaxed to spur economic growth.

This month, when Germany announced it would halt spending from its $39 million fund for conservation efforts in Brazil, Mr. Bolsonaro said Brazil didn’t need the money. He said he had “a message to dear Madam Angela Merkel,” referring to Germany’s chancellor.

“Take that money and use it to reforest Germany, O.K.? You need it way more than we do here.”

When a reporter asked Mr. Bolsonaro in early August if economic growth and sustainable development could coexist, the president responded with a crude remark, saying that all people had to do was defecate “every other day, and you will really make everyone’s life better that way.”

“All you need to do is eat a little bit less.”

Mr. Bolsonaro also recently announced that a sliver of coastline in Rio de Janeiro, a region in his home state that is currently a wildlife reserve, could lose that designation and be developed into a “Brazilian Cancun.”