Page 129 - Fundamentals of Air Pollution

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Effects on Health and

Human Welfare

I. AIR-WATER-SOIL INTERACTIONS

The harmful effects of air pollutants on human beings have been the
major reason for efforts to understand and control their sources. During
the past two decades, research on acidic deposition on water-based ecosys-
tems has helped to reemphasize the importance of air pollutants in other
receptors, such as soil-based ecosystems (1). When discussing the impact
of air pollutants on ecosystems, the matter of scale becomes important. We
will discuss three examples of elements which interact with air, water, and
soil media on different geographic scales. These are the carbon cycle on a
global scale, the sulfur cycle on a regional scale, and the fluoride cycle on
a local scale.

A. The Carbon Cycle: Global Scale

Human interaction with the global cycle is most evident in the movement
of the element carbon. The burning of biomass, coal, oil, and natural gas
to generate heat and electricity has released carbon to the atmosphere and
oceans in the forms of CO 2 and carbonate. Because of the relatively slow

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