Indigenous communities 'among the very few best protectors' of Peruvian Amazon

Small-scale gold mining often involves the use of mercury, a neurotoxin, to separate ore from substrate. In 2011 alone, nearly 1,400 tons of mercury was used for gold mining, making it the world’s largest source of environmental mercury pollution. Oil and natural gas extraction, too, often releases dangerously high levels of heavy metals into rivers, according to the report. 

And the roads that these industries build, while a boon for commerce, tend to perpetuate a cycle of forest destruction. “A huge impact of the roads is the migration it causes,” said Robert Guimaraes, vice president of FECONAU, an indigenous federation in Ucayali in the report. “With them comes a cocktail of problems: illegal logging, coca cultivation and illegal mining.” 
http://news.mongabay.com/2014/1212-gfrn-cannon-indigenous-groups-forest-protection.html