“The best thing you could do for the Amazon is to blow up all the roads.” These might sound like the words of an eco-terrorist, but it’s actually a direct quote from Professor Eneas Salati, a forest climatologist and one of Brazil’s most respected scientists.
Many scientists share Salati’s anxieties because we’re living in the most explosive era of road expansion in human history. The International Energy Agency (IEA) predicts that by 2050 we will have 60% more roads than we did in 2010. That’s about 25 million kilometres of new paved roads — enough to circle the Earth more than 600 times.
In new research published today in Nature, we’ve developed a global “roadmap” of where to put those roads to avoid damaging the environment. Our maps are also available to the public on a new website.
Roads today are proliferating virtually everywhere — for exploiting timber, minerals, oil and natural gas; for promoting regional trade and development; and for building burgeoning networks of energy infrastructure such as hydroelectric dams, power lines and gas lines.
Even national security and paranoia play a role. The first major roads built in the Brazilian Amazon were motivated by fears that Colombia or the US might try to annex the Amazon and steal its valuable natural resources. India’s current spate of road building along its northern frontier is all about defending its disputed territories from an increasingly strident China.
According to the IEA, around nine-tenths of new roads will be built in developing nations, which sustain the most biologically important ecosystems on Earth, such as tropical and subtropical rainforests and wildlife-rich savanna-woodlands.
Crucially, such environments also store billions of tonnes of carbon, harbour hundreds of indigenous cultures, and have a major stabilizing influence on the global climate.
Why are roads regarded as disasters for nature?
Far too often, when a new road cuts into a forest or wilderness, illegal poachers, miners, loggers or land speculators quickly invade — unleashing a Pandora’s box of environmental problems.
For instance, my colleagues and I recently found that 95% of all forest destruction in the Brazilian Amazon has occurred within 5 kilometres of roads (notably, we also found that many Amazonian roads are illegal; for every kilometre of legal road, there were three kilometres of illegal roads). Other research has shown that major forest fires spike sharplywithin a few dozen kilometres of Amazon roads.
The Congo Basin is reeling from a spree of forest-road building by industrial loggers, with over 50,000 kilometres of new roads bulldozed into the rainforest in recent years. This has opened up the forest to a tsunami of hunting. The toll on wildlife has been appalling; in the last decade, for instance, around two-thirds of all forest elephants have been slaughtered for their valuable ivory tusks.
In Peru, a new highway slicing across the western Amazon has led to a massive influx of illegal gold miners into formerly pristine rainforests, turning them into virtual moonscapes and polluting entire river systems with the toxic mercury they use to separate the gold from river sediments.
Image Credit: WWF-Malaysia/Lau Ching Fong