Biologists have long known that large areas of roadless space are generally far more beneficial to the natural environment than multiple smaller areas broken up by roads. Roads lead to increased human activity, groundwater contamination, introduction of invasive species, and other environmental compromises. A new mathematical analysis, published in the May 4 Science, offers a visual model of the quantity and distribution of roadless areas in the United States, providing a clear and useful guide to the ecological value of land for scientists and policymakers.
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“If you’re talking about your stock portfolio, you don’t just say ‘I have 768 shares of stock’ and stop,” says Raymond Watts, a geographer at the U.S. Geological Survey Science Center in Fort Collins, Colorado and lead researcher on the project. “You look at the value of the various shares of stock you have.” Similarly, Watts and his team of researchers wanted to know how much environmental “wealth” the United States has in open space, taking into account the high value of remote land.