Today, Plantlife publishes a report on air pollution and its impacts on Wales’ magnificent wildlife – an issue which resonates across the UK. We’re raising the alarm about recent increases in ammonia emissions from farming - one of the main sources of nitrogen pollution to the air.
The rise in dense clusters of intensive poultry units in some areas is a particular concern, as each unit may be unregulated but their cumulative impacts are devastating.
High concentrations of ammonia, such as from these units, are deposited onto nearby habitats, with visible impacts on lichens (a traditional indicator of air quality) and other vegetation. At some of Wales’ most important woodland and parkland SSSIs, staff from Natural Resources Wales have found algal gunk smothering lichens on trees nearer to intensive farming operations, whereas healthy lichens are found on trees in other parts of the site. In other cases, lichens and other vegetation are bleached and killed by the pollution.
More broadly, farm ammonia and nitrogen oxides (NOx) from transport, industry and homes are enriching and acidifying our most important wildlife habitats – Plantlife recently highlighted the impact of road traffic emissions on road verge wildflowers. Even in remote uplands, excess nitrogen levels are found in bogs and heaths, as nitrogen can travel long distances in the atmosphere.
The good news is that the UK government’s proposed Clean Air Strategy set out new requirements for farm businesses in England to cut ammonia emissions. We’re calling on the Welsh Government and other devolved administrations to follow suit. Unlike NOx and most other air pollutants, ammonia is largely unregulated; only the largest pig and poultry units have to control emissions as a condition of their environmental permit. It’s estimated that these units account for 5% of farm ammonia emissions in Wales; the remaining 95% - from all beef, dairy and sheep farming, fertiliser management and smaller pig and poultry units – is unregulated.
There’s lots of other good reasons to regulate ammonia – it damages people’s health by helping to form fine particulate matter. Ammonia is also partly converted in the air to nitrous oxide (N2O), a powerful greenhouse gas. Many of the practical steps involved – covering slurry stores, efficient use of fertilisers and improved animal housing – will also prevent water pollution, boost animal welfare and mitigate climate change.
What about the wildlife and habitats that are already affected?
More than 96% of England’s semi-natural wildlife habitat – on land and water – already has excess nitrogen from air pollution, making our semi-natural grasslands, woodlands, heaths and bogs too fertile and too acidic. Air pollution is also a major pathway by which nitrogen reaches freshwater and marine habitats, contributing to eutrophication and acidification. Nitrogen-tolerant plants, fungi and lichens thrive, while those that prefer low nutrient conditions are wiped out – along with the insects and other wildlife that depend upon them.
While cuts in emissions must be a priority, the Clean Air Strategy should also set out targeted action to protect and restore wildlife species and habitats, including:
- prioritisation and funding for Natural England’s Shared Nitrogen Action Plans (SNAPs) at European Special Areas of Conservation (SACs). These are designed to engage local stakeholders in a plan to reduce nitrogen levels and restore the habitat. Progress on pilot projects has been slow, under-funded and low profile;
- factoring nitrogen deposition and its impacts into the monitoring, assessment and management of all SSSIs. A methodology has been developed for this by the statutory agencies, but it has yet to be approved and implemented.
So to mark National Clean Air Day, take the time to read and respond to the government’s consultation to secure clean air for wildlife and people.
Jenny Hawley, Senior Policy Officer, Plantlife
The opinions expressed in this blog are the author's and not necessarily those of the wider Link membership.
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