Brazilian President Luiz Inacio Lula da Silva is set to lead tributes to the Amazon rubber-tapper Chico Mendes on the 20th anniversary of his murder.
Mr Mendes is seen as a pioneer of the environmental movement who mobilised local forest communities to stop the advance of loggers and ranchers.
He was shot dead outside his home in the state of Acre on 22 December 1988.
His legacy was the creation of a network of reserves where people can make a living from the forest.
Mr Lula is expected to make a television address on Monday night to pay homage to Mr Mendes.
The rubber-tappers' leader had spent years encouraging poor communities to protect the rubber trees that gave them their livelihood against large landowners who wanted to clear the forest for cattle ranching.
Pressures
After Mr Mendes's murder, the government began to set up extractive reserves, which now number 20 and where a limited ...