Spatial extent of road pollution: A national analysis

Authored by sciencedirect.com and submitted by Wagamaga

Roads form vast, pervasive and growing networks across the Earth, causing negative environmental impacts that spill out into a ‘road-effect zone’. Previous research has estimated the regional and global extent of these zones using arbitrary distances, ignoring the spatial distribution and distance-dependent attenuation of different forms of road environmental impact. With Great Britain as a study area, we used mapping of roads and realistic estimates of how pollution levels decay with distance to project the spatial distribution of road pollution.

We found that 25% of land was less than 79 m from a road, 50% of land was less than 216 m and 75% of land was less than 527 m. Roadless areas were scarce, and confined almost exclusively to the uplands (mean elevation 391 m), with only ca 12% of land in Great Britain more than 1 km from roads and <4% of land more than 2.5 km from roads. Using light, noise, heavy metals, NO 2 , and particulate matter PM 2.5 and PM 10 as examples, we estimate that roads have a zone of influence that extends across >70% of the land area. Potentially less than 6% of land escapes any impact, resulting in nearly ubiquitously elevated pollution levels. Generalising from this, we find that, whilst the greatest levels of road pollution are relatively localised around the busiest roads, low levels of road pollution (which may be ecologically significant) are pervasive.

Our findings demonstrate the importance of incorporating greater realism into road-effect zones and considering the ubiquity of road pollution in global environmental issues. We used Great Britain as a study area, but the findings likely apply to other densely populated regions at present, and to many additional regions in the future due to the predicted rapid expansion of the global road network.

jamany on March 13rd, 2021 at 15:57 UTC »

"just 1%" is an odd way to put it

zombiesunflower on March 13rd, 2021 at 15:56 UTC »

One thing I've never heard anyone talk about really is what effect on groundwater asphalt has when it's first laid and over time.

Chrisnothing on March 13rd, 2021 at 15:21 UTC »

If only we hadn’t butchered the trainlines

Edit:

There's a lot of misinformation being spread in the comments below.

Here's a good video on how rail privatisation has failed.