William Laurance writing at Yale Environment360:
Although the direct effects of roads are serious, they pale in comparison to the indirect impacts. In tropical frontier regions, new roads often open up a Pandora’s box of unplanned environmental maladies, including illegal land colonization, fires, hunting, gold mining, and forest clearing. “The best thing you could do for the Amazon,” said the respected Brazilian scientist Eneas Salati, “is to bomb all the roads.”
Big projects like the Belo Monte dam receive the lion’s share of attention, but the profusion of roads in the Amazon poses a greater threat. That’s not to say Belo Monte is net-positive for the environment—it’s probably not—but while we’re gasping in horror at the big gash, the Amazon is busy bleeding to death from a thousand smaller cuts.