Europe's sensitive ecosystems are under threat from excessive levels of air pollution, despite marked improvements over the past two decades, according to a report from the European Environment Agency.
The report, entitled “Effects of air pollution on European ecosystems”, assessed the proportion of European ecosystems exposed to nitrogen and sulphur-containing pollutants above sustainable levels. It reveals that, while cuts in sulphur dioxide emissions have reduced acidification in recent years and helped some natural habitats to recover, emissions of ammonia (NH3) from agricultural activities and nitrogen oxides (NOX) from diesel vehicles and other combustion processes has increased, resulting in NH3 and NOX now being the main cause of surface water and soil acidification across parts of Europe.
The rapid accumulation of nitrogen in the soil damages ecosystems by feeding some beneficiaries, such as grass, heather, thistles and nettles, while crowding out a wide range of other species, including flowers, bees, beetles, and spiders, by depriving them of water, space and light. Nitrogen-rich leachates entering surface waters and groundwater, also increases the risk of eutrophication in rivers and lakes, which further damages marine life.
Hans Bruyninckx, executive director at the agency, commented: “Although air pollution does not cause as much harm as it once did, we are still struggling to protect sensitive ecosystems from harmful effects such as eutrophication. This changes habitats, endangering a wide range of species from fish to flowering plants. It is particularly striking that the problem appears to be just as bad in Europe’s protected natural areas.”
A recent report from the UK’s joint nature conservancy council (JNCC) also found compelling evidence of the risks to biodiversity from nitrogen emissions and says that critical loads for the protection of habitats from nitrogen deposition are being exceeded over large areas of Europe. Clare Whitfield, joint author of the study, said: “Nitrogen represents a major threat to biodiversity in the UK and across Europe. It is an under-acknowledged and very big issue that has slowly crept up on us.”
