Trends in precipitation chemistry, surface water chemistry and aquatic biota in acidified areas in Europe and North America from 1990 to 2008 (ICP Waters report 106/2011)

Abstract

Results from international monitoring programmes on precipitation chemistry and surface water chemistry and biota for the time period 1990 to 2008 are reported here. Concentrations of sulphate and nitrate in precipitation in large areas in Europe and North America have decreased due to reduction of emissions to the atmosphere. For sulphate in surface waters, the same pattern can be seen although the reduction is not as large as in precipitation. Nitrate, however, does not show uniform decreasing trends. The acidity of lakes and rivers has decreased and in many areas there are good conditions for recovery of aquatic biological communities. Several areas in Europe will, however, not achieve good (non-acidified) water quality with current legislation of emissions of acidifying components. Future reductions of both S and N deposition are necessary to achieve biological recovery.