In the air quality directive (2008/EC/50), the EU has set a critical level for nitrogen oxides (NOx) for the protection of vegetation within the zones designated by member states: the NOx annual mean value may not exceed 30 micrograms per cubic metre (µg/m3).
EEA standard re-use policy: unless otherwise indicated, re-use of content on the EEA website for commercial or non-commercial purposes is permitted free of charge, provided that the source is acknowledged (http://www.eea.europa.eu/legal/copyright). Copyright holder: European Environment Agency (EEA).
Appreciate wildlife, but be sure to watch wild animals from a distance and avoid feeding them. Remember, the scent you leave when you touch a nest or a lair may scare the parents off for good. Instead of touching, try to find out more about them and maybe even discover how you can contribute to their protection.
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