When Sebasti?o Salgado sent his first photos in 1986 from a frenzied gold rush in the Amazon to the New York Times magazine, there was silence in the office. Peter Howe, then the magazine’s photo editor, later recalled that it was the only time in his career that “photographs caused text editors to be both speechless and engrossed”.

Mr Salgado had spent a month at Serra Pelada, on the south-east of the Amazon rainforest in Brazil, where he photographed a vast pit dug out by hand and the men desperate to find their fortunes. Seeing the epic scale of the images, with hundreds of labourers climbing in unison up the ladders at the side of the crater, huge bags of soil on their backs, the common reaction was to compare them to the pyramid-builders. The work sealed Mr Salgado’s reputation as the documentarist of his era.

The photos were first published just as concern about the destruction of the Amazon was starting to become an international cause célèbre. Three decades later, Mr Salgado’s photos are on display again — an exhibition opened in S?o Paulo this month before starting a four-nation tour. And the Amazon is once again back in the headlines.