Deterioration of copper and bronze caused by acidifying air pollutants

The ‘ICP on effects on materials’ was launched in 1985, within the framework of the Convention on Long-range Transboundary Air Pollution with the aim to find an approach for clearing the main gaps in the knowledge about material degradation caused by environmental impacts. The project was organized as a staggered8 year's material exposure programme accompanied by an extensive measuring programme for environmental parameters. During the evaluation of the 4 years data set it took shape that the most efficient parameters for quantifying the material degradation are the mass loss and especially for copper the corrosion volumes. Bronze already reacts extremely sensitive on low SO₂ concentrations. The starting corrosion rate for copper is suprisingly high. A strong impact of chloride on the formation of pin holes for sheltered copper could be detected without showing high mass loss. At simultanous presence of ozone the corrosive action is catalysed by it's oxidation power and leads to severe mass loss. Based upon the 4 years data set for most of the materials preliminary dose-response-functions have been prepared. For the first time a synergetic effect of SO₂ and ozone has been demonstrated in a field exposure.     

Soil Contamination Caused by Emergency Bio-Reduction of Catastrophic Livestock Mortalities

Water, Air, & Soil Pollution - The variations of tropospheric ozone levels was assessed for the first time in the Boukornine National Park (N.E. Tunisia) by detection of leaf injury development...     

Mapping critical levels of ozone,sulfur dioxide and nitrogen dioxide for crops,forests and natural vegetation in the United States

Air pollution abatement strategies for controlling nitrogen dioxide, sulfur dioxide, and ozone emissions in the United States focus on a ‘standards-based’ approach. This approach places limits on air pollution by maintaining a baseline value for air quality, no matter what the ecosystem can or cannot withstand. In this paper, we present example critical levels maps for the conterminous U.S. developed using the ‘effects-based’ mapping approach as defined by the United Nations Economic Commission for Europe's Convention on Long-Range Transboundary Air Pollution, Task Force on Mapping. This approach emphasizes the pollution level or load capacity an ecosystem can accommodate before degradation occurs, and allows for analysis of cumulative effects. We present the first stage of an analysis that reports the distribution of exceedances of critial levels for NO₂, SO₂, and O₃ in sensitive forest, crop, and natural vegetation ecosystems in the contiguous United States. We conclude that extrapolation to surrounding geographic areas requires the analysis of diverse and compounding factors that preclude simple extrapolation methods. Pollutant data depicted in this analysis is limited to locationally specific data, and would be enhanced by utilizing spatial statistics, along with converging associated anthropogenic and climatological factors. Values used for critical levels were derived from current scientific knowledge. While not intended to be a definitive value, adjustments will occur as the scientific community gains new insight to pollutant/receptor relationships. We recommend future analysis to include a refinement of sensitive receptor data coverages and to report relative proportions of exceedances at varying grid scales.     

Mapping Ozone Critical Levels for Vegetation in Central Italy

Within the framework of the UN-ECE Convention on Long-Range Trans-boundary Air Pollution, critical ozone levels for forest trees and crops have been determined. This paper shows the mapping results of short and long-term threshold exceedances in an area of Central Italy. Eighty-thousand hourly mean ozone concentrations were recorded and computed to evaluate the potential distribution of the pollutant in the area. The results suggest that the threshold is frequently exceeded in the summer, and this may be very critical for the plants' health.     

Developing optimal abatement strategies for the effects of sulphur and nitrogen deposition at European scale

Integrated Assessment Models were successfully used to provide input to the negotiations for the Oslo Protocol on Further Reductions of Sulphur Emissions, finalized within the United Nations Economic Commission for Europe Convention on Long-range Transboundary Air Pollution in Oslo in June 1994. The techniques developed within this framework will be extended now to the simultaneous analysis of sulphur and nitrogen deposition. In addition to acidification, atmospheric deposition of nitrogen contributes to eutrophication of certain ecosystems, through a nutrient effect, and originates from the long-range transport of emissions of both oxidised and reduced nitrogen (NO_x and NH₃). Modelling reductions in nitrogen deposition thus introduces a need to establish multi-pollutant multi-effect modelling techniques. This paper investigates the development of a model set up to examine reductions of these pollutants in an economically and environmentally efficient manner. The control of nitrogen deposition encompasses action across several economic sectors, particularly the power, transport and agricultural sectors. Combining sulphur and nitrogen deposition limits on a European scale will require a flexible modelling approach and the issues governing possible approaches are presented.     

Measurements of Ozone Deposition to Vegetation Quantifying the Flux,the Stomatal and Non-Stomatal Components

Water, Air, &; Soil Pollution - Ozone deposition to vegetation represents the major sink for boundary layer ozone and yet the underlying mechanism of reaction and uptake at the surface is poorly...     

Establishing critical levels for the effects of air pollution on vegetation

In recent years, international air pollution effects research has focused on setting critical levels of pollutants, above which adverse effects occur on sensitive receptors. Once established, these levels are used to determine the geographical extent of exceedance for different vegetation categories and ultimately in the development of international protocols for pollution control within the Convention on Long-range Transboundary Air Pollution. Ideally, the critical level for each pollutant and vegetation category should have a relatively simple definition to allow ease of mapping. Nevertheless, the definitions need to be sufficiently robust to apply to sensitive vegetation growing in a diverse range of climates. The restrictions imposed by these criteria have led to complex and delicate negotiations between scientists from the UN/ECE* region. Data for the direct effects of air pollutants on vegetation have been carefully reviewed for applicability to critical levels. To date, critical levels have been set for the effects of SO₂, ozone, NOx and NH₃ on crops, trees and natural vegetation. The use of effects data to establish these levels is critically assessed in this paper in relation to current and future requirements for mapping.     

Numerical Simulation of the Springtime Trans-Boundary Air Pollution in East Asia

Water, Air, &; Soil Pollution - During the spring, the high concentrations of ozone (O3) and aerosols are frequently observed aloft in Japan. Such episodes supposedly are caused by the...     

An Integrated Feasibility Study on Designing Remediation Systems for Petroleum-Contaminated Sites

Water, Air, & Soil Pollution - This paper presents an integrated feasibility study on designing systems for remediating petroleum-contaminated sites. Its consists of components of...     

An integrated analysis of sulfur emissions,acid deposition and climate change

This paper presents one of the first integrated analyses of acidification and climate change on a geographically-detailed basis, and the first linkage of integrated models for acid deposition (RAINS) and for climate change (IMAGE 2). Emphasis in this paper is on Europe. Trends in driving forces of emissions are used to compute anthropogenic SO₂ emissions in 13 world regions. These emissions are translated into regional patterns of sulfur deposition in Europe and global patterns of sulfate aerosols using source-receptor matrices. Changes in climate are then computed based on changes in sulfate and greenhouse gases. Finally, we compute ecosystem areas affected by acid deposition and climate change based on exceedances of critical loads and changes in potential vegetation. Using this framework, information from global and regional integrated models can be used to link sulfur emissions with both their global and regional consequences. Preliminary calculations indicate that the size of European area affected by climate change in 2100 (58%) will be about the same as that affected by acid deposition in 1990. By the mid 21st century, about 14% of Europe's area may be affected by both acid deposition and climate change. Also, reducing sulfur emissions in Europe will have both the desirable impact of reducing the area affected by acid deposition, and the undesirable impact of enhancing climate warming in Europe and thus increasing the area affected by climate change. However, for the scenarios in this paper, the desirable impact of reducing sulfur emissions greatly outweighs its undesirable impact.