[Show abstract][Hide abstract] ABSTRACT: Transboundary Air Pollution (LRTAP). However, outcomes vary widely depending on the approach. Weathering rates and the gibbsite equilibrium greatly influence the endurable rates for sulphur and nitrogen deposition obtained, likely due to individual buffering capacities in the soils. The authors use different approaches to calculate CL for acidity and eutrophying nitrogen and compare them with the development of base cation leaching, the base cations–aluminium ratio, and acid neutralising
capacity. Furthermore change in pH as well as potential changes in foliar magnesium, calcium, and potassium content are looked at to detect effects on or even shifts within ecosystem functioning. Data derived from the ICP Forests database provide a timeseries on deposition, soil and foliar chemistry, growth, and tree condition. Initial results confi rm signifi cant variation in CL values due to methodological issues. Calculated CL exceedances are not necessarily manifested in a growth decline; on other sites a
decline in tree health is observed even though no exceedances have occurred. The aim of this ongoing work is to modify CL calculations depending on forest ecosystem responses.
IUFRO World Congress, Salt Lake City, USA; 10/2014
[Show abstract][Hide abstract] ABSTRACT: Atmospheric deposition to forests has been monitored within the International Cooperative Programme on Assessment and Monitoring of Air Pollution Effects on Forests (ICP Forests) with sampling and analyses of bulk precipitation and throughfall at several hundred forested plots for more than 15 years. The current deposition of inorganic nitrogen (nitrate and ammonium) and sulphate is highest in central Europe as well as in some southern regions. We compared linear regression and Mann-Kendall trend analysis techniques often used to detect temporal trends in atmospheric deposition. The choice of method influenced the number of significant trends. Detection of trends was more powerful using monthly data compared to annual data. The slope of a trend needed to exceed a certain minimum in order to be detected despite the short-term variability of deposition. This variability could to a large extent be explained by meteorological processes, and the minimum slope of detectable trends was thus similar across sites and many ions. The overall decreasing trends for inorganic nitrogen and sulphate in the decade to 2010 were about 2% and 6%, respectively. Time series of about 10 and 6 years were required to detect significant trends in inorganic nitrogen and sulphate on a single plot. The strongest decreasing trends were observed in western central Europe in regions with relatively high deposition fluxes, whereas stable or slightly increasing deposition during the last 5 years was found east of the Alpine region as well as in northern Europe. Past reductions in anthropogenic emissions of both acidifying and eutrophying compounds can be confirmed due to the availability of long-term data series but further reductions are required to reduce deposition to European forests to levels below which significant harmful effects do not occur according to present knowledge.
Forest Condition in Europe, 2012 Technical Report of ICP Forests., Edited by Lorenz M., Becher G., 01/2012: chapter 5. Exceedance of critical limits and their impact on tree nutrition.: pages 77-91; Thünen Institute for World Forestry.
[Show abstract][Hide abstract] ABSTRACT: This paper presents the variation of sulphur and nitrogen deposition and the exceedance of their critical loads on Level II ICP Forests plots. The fact that critical loads are still exceeded at many forest sites in Europe indicates a continuing need for further implementation of air pollution abatement strategies. Such results contribute to the scientific basis for the development and reviews of the effectiveness of clean air politics by the Convention on Long-range Transboundary Air Pollution.
[Show abstract][Hide abstract] ABSTRACT: Intensive forest monitoring by means of harmonised methods has been conducted in Europe for more than a decade. Risks of atmospheric nitrogen and sulphur deposition are assessed by means of calculations of critical loads and their exceedances. In the present study throughfall and bulk deposition of nitrate (N-NO(3)), ammonium (N-NH(4)) and sulphate (S-SO(4)) show marked spatial patterns and temporal trends. In the period of observation (1999-2004), sulphate deposition on intensive monitoring plots decreased by about one quarter. This is in line with the reduction of S deposition by 70% since 1981 in Europe as a result of successful air pollution control politics under the Convention on Long-range Transboundary Air Pollution (CLRTAP). However, sulphate and especially nitrate and ammonium deposition were found to still exceed critical loads at many forest sites, indicating a continued need for further implementation of air pollution abatement strategies.
[Show abstract][Hide abstract] ABSTRACT: Forest condition in Europe has been monitored for 20 years jointly by the United Nations Economic Commission for Europe (UNECE) and the European Union (EU). Large‐scale variations of forest condition over space and time in relation to natural and anthropogenic factors are assessed on about 6000 plots systematically spread across Europe. Causal relationships are studied in detail on about 860 intensive monitoring plots covering the most important forest ecosystems in Europe. This paper describes results of the large‐scale defoliation survey, relationships between large‐scale defoliation and modelled large‐scale deposition, as well as of changes in concentrations of air pollutants in bulk deposition measured on intensive monitoring plots. There is an increase in defoliation of the most abundant species, with high spatial and temporal variation. Bulk deposition measurements indicate that sulphate and nitrate concentrations decreased from 1996 to 2001, whereas ammonium concentrations fluctuated during the same measuring period.
International Journal of Environmental Studies 01/2008; 65(3):299-309.
[Show abstract][Hide abstract] ABSTRACT: Forest health status in Europe is assessed by the International Cooperative Programme on Assessment and Monitoring of Air Pollution Effects on Forests (ICP Forests). Established by the Convention on Long-Range Transboundary Air Pollution (CLRTAP) under the United Nations Economic Commission for Europe (UNECE), the ICP Forests has been monitoring forest condition in close cooperation with the European Commission (EC) for 20 years. The present paper describes the latest results of the deposition measurements on permanent monitoring plots and of the extensive defoliation sample survey. The findings reveal marked spatial patterns in bulk and throughfall depositions of nitrate (N-NO3(-)), ammonium (N-NH4(+)), and sulfate (S-SO4(2-)), as well as an obvious decrease in bulk and throughfall deposition of sulfate. Latest analyses of defoliation data confirm previous results, indicating a high correlation with weather extremes.
The Scientific World Journal 02/2007; 7 Suppl 1:22-7. · 1.73 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Forest conditions in Europe have been monitored over 20 years jointly by the International Cooperative Programme on Assessment and Monitoring of Air Pollution Effects on Forests (ICP Forests) and the European Union (EU). Maps for mean bulk SO4, NO3 and NH4 deposition at around 400 intensive monitoring plots in the years 1999–2001, as well as time trends for the period 1996–2001, are presented. Mean bulk SO4 deposition at 169 plots mostly located in central Europe decreased from 7.4 to 5.8 kgS ha−1 a−1. Mean NH4 bulk deposition decreased from 6.2 to 5.3 kgN ha−1 a−1. Nitrate bulk deposition fluctuated around 5 kgN ha−1 a−1. On average, throughfall deposition was considerably higher than bulk deposition. Time trends for mean tree crown defoliation as an overall indicator for forest condition show a peak in the mid 1990s for most of the monitored main tree species and a recent increase for the years 2003 and 2004. Multivariate linear regression analyses show some significant relations between deposition and defoliation. These relations depend on the tree species and site characteristics. Effects of deposition are moderated by the influence of biotic stress factors such as insects and fungi and by abiotic stress factors, such as weather.
[Show abstract][Hide abstract] ABSTRACT: Concerns on the harmful effects of air pollutants in 1970s prompted international collaboration to combat air pollutants at their sources. The Convention on Long-range Transboundary Air Pollution was established in 1979, with subsequent setup of its working bodies. They included the Working Group on Effects, which laid the basis for the cooperative monitoring and research of air pollution effects. This group comprises several international cooperative programmes and task forces. They cover a variety of receptors from ecosystems (forests, surface waters, vegetation) to materials and health effects on populations, including mapping activities and integrated monitoring. The research addresses many interlinking environmental problems and causative pollutants: acidification, terrestrial eutrophication, health effects, corrosion, ozone, particulate matter, contamination by heavy metals and persistent organic pollutants. The observational and modelling results cover the geographical area United Nations Economic Commission for Europe (UNECE) and the recorded trends span more than 15 years. The effect-oriented work has initiated and supported the development of several air pollutant emission reduction protocols under the Convention, some based on effects-based model calculations. The cooperation has created a nexus of observational networks and interdisciplinary policy-linked research unique in the world.
[Show abstract][Hide abstract] ABSTRACT: For 20 years the Convention on Long-range Transboundary Air Pollution has worked to control air pollutant emissions in Europe and North America. Its Working Group on Effects (WGE) has been responsible for much of the underpinning science. The WGE's six International Cooperative Programmes (ICPs) on Waters, Natural Vegetation and Crops, Forests, Materials and Cultural Heritage, Integrated Monitoring, and Modelling and Mapping, together with a Joint Task Force on Human Health with WHO, quantify air pollution effects on the environment through monitoring, modelling and scientific review. Early work found evidence to support the need for decreases in emissions of sulphur and nitrogen pollutants. More recently, monitoring results and models have provided the scientific basis, e.g. critical loads and levels, for effects-based Protocols and for evaluating their effectiveness. ICP studies on trends show recovery from acidification effects in keeping with the fall in sulphur emissions. Steady-state models provide an indication of long-term improvements. Recent increased emphasis on developing dynamic models will enable better links between recovery rates and abatement strategies. The scientific network of the ICPs and the monitoring and modelling results have been key to the development of the Convention and are an essential component for its success in the future.
Water Air and Soil Pollution 01/2001; 130(1):119-130. · 1.75 Impact Factor