May 3, 2007 — A new method for evaluating the land in between roads could improve efforts to preserve wild areas and plan urban communities.
In the continental United States, roads are never more than a reassuring 22 miles away. Their ubiquity makes travel and transport convenient for people, but it can also fragment or destroy wildlife habitats, help introduce invasive species, and contribute to pollution.
The further an environment is from a road, the less it is affected by those things. But traditional tools for analyzing roadless space have ranked a plot of land one mile from a road the same as one several miles from a road.
The new method for evaluating roadless space takes those differences into account.
"Having a way to measure roadless space is a very general way of expressing how much natural landscape we have out there. Our metric, at most, bends over backwards to express the invulnerability of that area," said Raymond Watts, a scientist at the Rocky Mountain Geographic Science Center and USGS Fort Collins Science Center in Colorado.
Watts and his colleagues published the results of their study in this week's issue of Science.
The researchers compiled roadless space data in 100-foot intervals, county-by-county, across the 48 contiguous United States.
They calculated the remoteness of each point, converting the numbers into an altitude-style set of markings. The result is a map of peaks and valleys, where sections of land farthest from a road have the highest rise, and areas closest to roads have the lowest.
