In 63% of special areas of conservation, our best wildlife sites, nitrogen levels are already too high. This has dire consequences for animals, including pollinating insects, that depend on wild fungi and plants for food, nutrients and shelter. This affects us all, as biodiversity is vital to our health and wellbeing, our culture and our economy.
On National Clean Air Day, Thursday 15 June, we’re calling for action to cut air pollution which threatens our native wildlife (Nature needs fresh air too, 2 June). The UK government’s air quality consultation, closing on 15 June, focuses on “tackling nitrogen dioxide in our towns and cities”. That issue deserves urgent action – but it’s not enough. Air pollution is a problem in both rural and urban areas, for people and wildlife. We need to tackle the sources and solutions as a whole.
Nitrogen in air pollution acts as a fertiliser, making conditions too rich for many wild fungi and plants. That’s why you’re more likely to see nitrogen-tolerant species, such as common orange lichen, nettles and hemlock, on road verges and field margins – rather than bird’s foot trefoil, harebells or orchids, which are more sensitive. In 63% of special areas of conservation, our best wildlife sites, nitrogen levels are already too high. This has dire consequences for animals, including pollinating insects, that depend on wild fungi and plants for food, nutrients and shelter. This affects us all, as biodiversity is vital to our health and wellbeing, our culture and our economy.
Measures to cut air pollution from transport and other sources need to be extended across the country – not just urban areas. These include better green spaces, public transport, walking and cycling routes. In particular, much faster action is needed to cut ammonia emissions, which have not reduced in line with other pollutants. Ammonia is a precursor to particulate matter, affecting human health as well as nature. The main source is farming – livestock and fertilisers – requiring concerted action by farmers, industry and government.
Let’s have an air quality strategy that delivers for people and for wildlife.
Ian Denholm Chair, Botanical Society of Britain and Ireland
David Minter President, International Society for Fungal Conservation
Allan Pentecost President, British Lichen Society
Matt Shardlow Chief executive, Buglife
Marian Spain Chief executive, Plantlife
Stephen Trotter Director, Wildlife Trusts England
• It’s useful to know that people’s exposure to atmospheric pollution can be reduced by walking or cycling away from streets where it is at its worst (Walking on side streets can halve exposure to pollution, study says, 14 June), but it is important to realise that this advice refers mainly to exposure to NO2.
In fact, the health effects of pollution come not just from NO2 but also from small particulates (especially PM2.5s: particles that are up to 2.5 microns in size). NO2 concentrates mainly near the areas where it is produced (hence the advice), while for PM2.5s the fall in concentration over distance is much less, and even 100 metres away from the source – mainly vehicle engines – concentrations are still significant. Given that, according to other research from King’s College London, over a third of early deaths from pollution are caused by PM2.5s, it is clear that, while walking on side streets may help, it will not completely remove the damaging effects of pollution.
Dr Richard Carter
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