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Increasing
acidification deprives the soil of its nutrient reserves as well as releases
aluminium and certain heavy metals into the ground water, which when taken up
by plants, causes damage. In the tropics, biomass burning associated with land
clearing is widespread resulting in large quantities of sulphur dioxide and
nitrogen oxides released into the atmosphere. Although the impacts on our
forests have not been fully investigated, it is expected to increase leaching
of tropical soils. Scientific
studies strongly indicate that air pollutants, directly or indirectly, causes
forest damage at a regional level. Periods of drought and frost have a more
severe and long-lasting impact on trees already exposed to air pollution. The
extent of forest damage in Europe is a matter of very grave concern. For
example, high sulphur coal from the Black Triangle near the borders of
Germany, Czech and Poland was used as a fuel for power plants. Emissions of
sulphur dioxide from industrial processes caused significant damage to their
forests. A similar situation was observed in Chongqing, China. Sulphur
dioxide is emitted during the process of refining metals such as copper and
nickel that contain high levels of sulphur. In the past, forest dieback in
Ashio, Japan was due to high concentrations of sulphur dioxide generated from
its copper refining industry. Even now, we see similar damage occurring in
other parts of the world. For example, we can observe tens of kilometers of
dead forests around the metal refining factories in Kora Peninsula in the
western part of Russia. Impacts
on Buildings and Materials Dirty
air can cause irreplaceable damage to our historic and cultural monuments. If
existing pollutant levels persist or are aggravated, deterioration of our
historic buildings particularly those made of marble or stone, sculptures,
monuments and artifacts will accelerate. Can we allow our ties with history to
literally weather away before our eyes? Sulphur
dioxide affects the composition of leather, fabrics and paper causing
significant deterioration. Corrosion of iron and steel structures is most
extensive in polluted industrial sites. Have you seen what appear to be icicles on walls and eaves of old buildings and highways? Dirty raindrops seep into walls through cracks, dissolve calcium in concrete materials and then leach out the walls. They combine with carbon dioxide in the air and form calcium carbonate, which grows like icicles. Wherever we observe these “icicles”, we can find dirty droplets at the top of the “icicles”. |
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