Preface.- Modelling seasonal dynamics from temporal variation in agricultural practices in the UK ammonia emission inventory.- Inter-annual variations of ozone and nitrogen dioxide over Europe during 1958-2003 simulated with a regional CTM.- Field intercomparison of main components in air in EMEP.- Variations in the fluoride level in precipitation in a region of human impact.- Long term trends in sulphur and nitrogen deposition in Europe and the cause of non-linearities.- Trends in chemical composition of wet-only precipitation at rural French monitoring stations over the 1990-2003 period.- Monitoring long term trends in sulfate and ammonium in U.S. precipitation.- Temporal trend of non-sea salt sulfate and nitrate in wet deposition in Japan.- Sulfate and nitrate in precipitation and soil water in pine forests in Latvia.- Acid Rain in downtown Sao Paulo City, Brazil.- Atmospheric metal pollutants - archives, methods and history.- Nitrogen saturation of terrestrial ecosystems: some recent findings and their implications for our conceptual framework.- Effects of nitrogen deposition on bryophyte species composition of calcareous grasslands.- Atmospheric deposition of reactive nitrogen on turf grassland in central Japan: comparison of the contribution of wet and dry deposition.- Effects of nitrogen supply on the sensitivity to O3 of growth and photosynthesis of Japanese Beech seedlings.- Stem growth of Picea abies in south western Sweden in the ten years following limiting and addition of PK and N.- X-Ray microanalysis of needles from Douglas Fir growing in environments of contrasting acidity.- Effects of acid rain on competitive releases of cd, cu, zn, from two natural soils and two contamined soils in Hunan, China.- Modelling change in ground vegetation response to acid and nitrogen pollution, climate change and forest management in Sweden 1500-2100 AD.- Laboratory measurements of dry deposition of ozone onto northern chinese soil samples.- Ozone deposition to a coniferous and decidous forest in the Czech Republic.- Impact of harvest intensity on long-term base cation budgets in Swedish forest soils.- Long term effects of acid irrigation at the Hoglwald on seepage water chemistry and nutrient cycling.- Nitrogen budget of a Spruce forest ecosystem after six-year addition of ammonium sulphate in southwest Sweden.- Modification of soil solid Al phases during an extreme experimental acidification of A horizons of forest soils from southwest Europe.- Exposure programme on atmospheric corrosion effects of acidifying pollutants in tropical and subtropical climates.- The UN/ECE ICP materials dose-response functions for the multi-pollutant situation.- Long-term trends in surface water quality of five lakes in Japan.- The Fernow Watershed acidification study: ecosystem acidification, nitrogen saturation and base cation leaching.- Response of drinking water reservoir ecosystems to decreased acidic atmospheric deposition in SE Germany: signs of biological recovery.- Invasives, introductions and acidification: the dynamics of a stressed river fish community.- Fish stomachs as a biomonitoring tool in studies of invertebrate recovery.- Acidification at Plastic Lake, Ontario: has 20 years made a difference?.- Modeling acidification recovery on threatened ecosystems: application to the evaluation of the Gotenburg Protocol in France.- Recovery of acidified lakes:lessons from the Sudbury, Ontario, Canada.- Relationships between macroinvertebrate assemblages of stony littoral habitants and water chemistry variables indicative of acid-stress.- A novel environmental quality criterion for acidification in Swedish lakes -an application of studies on the relationship between biota and water chemistry.- Effects of liming on the aquatic fauna in a Norwegian watershed: why do crustaceans and fish respond differently?.- Recovery of acidified streams in forests treated by total catchment liming.- Cost-effectiveness analysis of reducing the emission of nit