Can roads have a positive effect on nature?
IN 1989, A WEALTHY real-estate developer named George Quaid illegally bulldozed a 32km road through the tropical rainforests of north Queensland, just north of Cairns. The infamous ‘Quaid Road’ is still prominent today, a jagged scar across the Wet Tropics World Heritage Area.
Australia has relatively few illegally constructed roads like Quaid’s folly, but they are far more common elsewhere. The Amazon Basin is crisscrossed by nearly 100,000km of paved and unpaved roads, many of them made illegally by loggers, miners and cattle ranchers. In recent years loggers have bulldozed over 50,000km of new roads through the Congo Basin.
Such roads can open a Pandora’s Box of environmental problems. For instance, over 95 per cent of all deforestation, fires and carbon emissions in the Amazon occur within 10km of roads. Logging roads allow illegal gold miners and poachers to penetrate deep into forests, often taking a severe toll on wildlife.
For reasons such as these, roads have earned a bad reputation among scientists. Surprisingly, however, some roads might actually help the environment. This conclusion underlies an argument I made, along with Professor Andrew Balmford from the University of Cambridge, last week in the journal Nature.
Environmental benefits of good roads
In many ways, our research asserts, roads are like real estate — it’s all about ‘location, location, location’. A new road located in the wrong place, such as one cutting through the heart of a forest, can provoke an environmental disaster, especially in frontier areas where illegal activities are common.
But in areas well-suited for farming and where most native forest has already been cleared, a high-quality road (or improvements, such as paving an existing dirt road) can actually be beneficial.
In such areas, good roads make it much easier to move crops to market and import fertilizers. This increases farm yields and profits and improves the livelihoods of rural residents. And, like a giant magnet, such roads tend to attract migrants away from vulnerable wilderness areas, concentrating them in highly productive farming zones.
Deforestation along roads in the southern Brazilian Amazon. (Credit: Google Earth)
Global population expected to reach 10 billion
Well-conceived roads will be crucial in the future. The global population is expected to peak at over 10 billion people late this century, with most of the increases occurring in developing nations. To meet demands, food production will need to double, requiring around 1 billion hectares of additional farming and grazing land, or an area the size of Canada.
Increasing agricultural yields so dramatically will place huge pressures on natural ecosystems. To limit the environmental impact, we need a global scheme for road building, a plan that shows where good roads should be placed and, crucially, where to avoid putting bad roads which could provoke environmental chaos.
It’s all about being proactive. Right now, farms and grazing lands in developing nations are springing up all over, with farmers simply following roads built for other purposes, such as logging or mining. Many farms end up in areas with marginal soil or climate, or that are too isolated to be profitable.
Transport and farming in the future
But with the global scheme Andrew and I have proposed, road-building and farming could be concentrated in the right places. Rather than spreading out all over and causing massive environmental harm, farming could be concentrated in areas where yields and profits will be maximized.
Creating a global road plan like this is achievable. We already have the basic information and expertise to do it reasonably well. The real challenge will be getting decision-makers, road planners and other stakeholders to use the zoning scheme.
That might not be easy, but we have to try. At the least, doing this will shine a spotlight on roads and the crucial roles they play in determining the footprints of agriculture and environmental degradation.
One thing is clear: keeping roads out of surviving wilderness areas is by far the most practical and cost-effective way to protect crucial ecosystems. In a world struggling to sustain nature while producing enough food for billions of new mouths, managing transport networks is where the rubber meets the road.
Professor William Laurance is an Australian Laureate at James Cook University in Cairns, Queensland. He also holds the Prince Bernhard Chair in International Nature Conservation at the University of Utrecht, Netherlands.