Air pollution is estimated to cause more than seven billion early deaths around the world every year – 40,000 in the UK and 2,500 in Scotland alone.
Now experts have said it’s not only a human health issue, but it is also driving a dramatic loss of plant diversity and pushing many wildlife habitats into critical condition.
They said the destructive effects of excess nitrogen from traffic fumes, burning of fossil fuels and agriculture is a far more immediate threat than climate change on the diversity of plants, lichens and fungi, killing delicate specimens and encouraging more “thuggish” species to thrive.
The report, which is backed by organisations including the National Trust, the Woodland Trust, RSPB and the Botanical Society of Britain and Ireland, spells out how tackling the destructive impact of atmospheric nitrogen deposition on plants and ecosystems is one of the biggest challenges for nature conservation.
The research shows 90 per cent of all nitrogen-sensitive habitats in England and Wales – such as heathlands, acid grasslands and sand dunes – are receiving deposition at higher levels than they can withstand. The UK-wide figure stands at 63 per cent.
As a result, low-nitrogen plants are declining, which means more than a third of flowering plants are at threat.
Dr Trevor Dines, Plantlife’s botanical specialist, said: “It is hard to exaggerate what a destructive impact nitrogen deposition is having on our wild flowers and other flora, fungi and ecosystems more broadly. Put simply, this report reveals that nitrogen deposition may present a far more immediate threat to semi-natural habitats than even climate change.”
He said nettles, hogweed and hemlock – “thuggish” species that thrive in soil steeped in excess nitrogen – are drowning out rare and more vulnerable species such as harebells.
He added: “We are force-feeding the natural world a diet of nutrient-rich junk food and it is having a devastating impact. Once-diverse habitats are becoming monotonous green badlands where only the thugs survive and other more delicate plants are being bullied out of existence.”
Scientists said urgent global action must be taken to cut air pollution, plus local measures to reduce its impact and increase nature’s resilience.