Where on Earth should roads go and not go?

"The best thing you could do for the Amazon is to blow up all the roads."

Road to ruin? (photo by Rhett Butler)

Those might sound like the words of an eco-terrorist, but it's actually a direct quote from Eneas Salati, a forest climatologist and one of Brazil's most eminent scientists.

Salati was saying it straight: far too often, roads open up a Pandora's Box of environmental problems -- allowing illegal loggers, miners, hunters, or land speculators to invade forests and other native ecosystems.  The results are often disastrous for nature.

But societies need roads -- for economic growth, to access land and natural resources, and for scores of other reasons.  Where on Earth should roads go and not go?

Today, in the leading journal Nature, ALERT director Bill Laurance and a team of co-authors from Harvard, Cambridge, Melbourne, James Cook and other universities present a global strategy for road building. 

Their paper advances a strategy for zoning and optimizing road locations, by assessing the relative environmental costs and economic benefits of road construction for every square kilometer of land on Earth.

You can download the paper for free here. 

And here is an insightful News & Views piece that Nature published about the article. 

And here is a popular, easy-to-read article that hits all the key points.

This paper has striking implications.  It shows the most critical areas to keep road-free, the areas where roads can have the greatest benefits for improving human welfare and food production, and the places where environmental conflicts are most likely to arise in the future.

By 2050, it's expected that there will be 25 million kilometers of new roads -- enough to circle the Earth more than 600 times. 

Nine-tenths of these new roads will be built in developing nations that sustain the biologically richest and most environmentally important ecosystems on the planet.

Deciding where this avalanche of new roads will go -- and not go -- is among the most critical environmental challenges we have ever faced.