The six year report: Acidification of surface water in Europe and North America. Dose/respons relationships and longterm trends (ICP Waters report)

The International Cooperative Programme on Assessment and Monitoring of Acidification of Rivers and Lakes is designed to: (1) establish degree and extent of acidification of surface waters, (2) evaluate dose/response relationships and (3) define long-term trends and variations in aquatic chemistry and biota attributable to atmospheric pollution. Data from 200 sites in 14 countries of Europe and North America are available in the database at Niva. Dose/response relationships show that the fauna are adapted to drifferent water qualities in different regions, and that critical limits for the fauna must be calculated according to data for the specific region. Long-term trends of water chemistry show decreases in SO4²- and Ca²+ at many sites. Nitrate shows no consistent trends