Rare plant and animal species are likely to decline or disappear as a result.
The Government's nature conservation arm estimates that about 600 Sites of Special Scientific Interest (SSSIs) out of a total of 2,619 have soil that is unable to counter current and future levels of acidity caused by air pollution, mostly from the burning of fossil fuels in power stations.
The main acid-rain pollutant, sulphur dioxide, is being reduced by 60 per cent between 1980 and 2003 under an European Community directive.
However, English Nature says that even after this cut is accomplished, the 600 SSSIs will still be vulnerable.
The sites are designated because they have rare plant and animal species or are particularly rich in wildlife. Those most at risk include woodlands,
lowland peatlands and lowland heathlands, some of which are internationally important for having
particularly rare plants and animals. Cumbria has more vulnerable SSSIs than any other English county - 88 in all covering more than 200 square miles.
Dr Andrew Farmer, air pollution specialist at English Nature, said: 'Sites whose soils are acidified . . . may never regain the variety and abundance of wildlife they once contained, let alone the rare species they were important for.'Reuse content