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UK Biodiversity Indicators 2023. Indicator B5a: Air pollution 2023


Updated 14 November 2023.

These documents support response indicator B5a – Air pollution. The documents include a datasheet and technical background document.

This indicator shows the proportion of sensitive habitat that is affected by two major impacts of air pollution: (i) acidification; and (ii) the excessive richness of nitrogen (eutrophication). The air pollutants sulphur dioxide, nitrogen oxides and ammonia can contribute to acidification; nitrogen oxides and ammonia can also contribute to terrestrial eutrophication. These pollutants arise mainly from burning fossil fuels and from livestock waste. Around a third of UK land area (78,000 square kilometres) is sensitive to acidification, and a third (73,000 square kilometres) to eutrophication (much of this area is sensitive to both). Critical loads are thresholds for pollutant load above which significant harmful effects may occur on sensitive habitats; statistics on critical load exceedance indicate the risk of damage.

These resources may not be fully accessible for all users. If you need a copy of any of these resources in a different or more accessible format, please get in touch.

More information on UK Biodiversity Indicator B5a is available on the UKBI B5a webpage.

Resource type Publication

Topic category Environment

Reference date 2023·11·14

Department for Environment, Food and Rural Affairs, UK. 2023. UK Biodiversity Indicators 2023.

The UK Biodiversity Indicators were created to provide a measure for reporting on the UK’s progress towards meeting international biodiversity goals and targets and were first published in 2007.

Responsible organisation
Communications, JNCC distributor

Limitations on public access No limitations

Use constraints Copyright of data and/or information presented in these resources may not reside solely with the distributor (JNCC). For more information, please contact

Metadata date 2023·11·14

Metadata point of contact
Communications, JNCC

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