Around 25 million kilometres of new paved roads are expected by 2050, with approximately 90 per cent of those to be built in developing nations.
These roads will facilitate accessibility and promote indispensable economic and social benefits. But new developments — particularly those that allow access to natural resources — leave delicate ecosystems vulnerable to the proliferation of unplanned or illegal roads.
Road networks are notoriously difficult to keep track of, and there are no mapped records of these unofficial roads. Thus, predictions of future environmental impacts lack accuracy.
“People are trying to predict future effects of infrastructure development using maps of roads that are 30 years old, and they’re assuming that the 30 year-old map is still going to be relevant in another 20 years. So it’s going to be a 50 year-old map of roads,” Jayden says.
“People are trying to predict future deforestation using historical records of infrastructure.”
Jayden says that more than half of the roads that exist across his study region are not mapped.
“There are a number of reasons roads throughout the Asia-Pacific aren’t mapped: they might be illegal or unofficial, or they could be roads that the government doesn’t consider to technically be a road, like logging tracks,” he says.
“It varies between countries. In Malaysia, only about three per cent of roads are actually mapped. So for every one kilometre of roads that we see on the map, there’s about 29 kilometres of roads that aren’t mapped.”
Part of Jayden’s PhD research involves completing the road maps using satellite imagery.
“We download the existing road maps and add them into Google Earth, and with the help of volunteers who are generously giving their time for this project, we go through and we manually trace the roads that aren’t in the maps,” he says.
“For some locations this process can be extremely time consuming. In the future, we hope to develop methods to automatically detect roads from satellite imagery using remote sensing.”
After establishing where the environmental impacts might occur and where they’re likely to spread, Jayden can begin developing methods to reduce these impacts. Although they can be extensive, his research focuses’ specifically on land cover change.
“For me, deforestation and habitat loss are some of the most important costs of road developments because if you don’t have any habitat, you can’t have any animals, regardless of what else is occurring,” he says.
“So, a way to preemptively mitigate the impacts of land cover change is to designate a place as a protected area before the development even goes ahead. Or in cases where that might not be possible, we can suggest changing a section of the highway and moving it a couple of kilometres, where it will have much less environmental impact.”