round aquifers.

greenhouse gas - a gas that "traps" infrared radiation in the
lower atmosphere causing surface warming; water vapor, carbon dioxide,
nitrous oxide, methane, hydrofluorocarbons, and ozone are the primary
greenhouse gases in the Earth's atmosphere.

groundwater - water sources found below the surface of the earth
often in naturally occurring reservoirs in permeable rock strata; the
source for wells and natural springs.

Highlands Water Project - a series of dams constructed jointly by
Lesotho and South Africa to redirect Lesotho's abundant water supply
into a rapidly growing area in South Africa; while it is the largest
infrastructure project in southern Africa, it is also the most costly
and controversial; objections to the project include claims that it
forces people from their homes, submerges farmlands, and squanders
economic resources.

Inuit Circumpolar Conference (ICC) - represents the 125,000 Inuits
of Russia, Alaska, Canada, and Greenland in international environmental
issues; a panel convenes every three years to determine the focus of
the ICC; the most current concerns are long-range transport of
pollutants, sustainable development, and climate change.

metallurgical plants - industries which specialize in the science,
technology, and processing of metals; these plants produce highly
concentrated and toxic wastes which can contribute to pollution of
ground water and air when not properly disposed.

noxious substances - injurious, very harmful to living beings.

overgrazing - the grazing of animals on plant material faster than
it can naturally regrow leading to the permanent loss of plant cover, a
common effect of too many animals grazing limited range land.

ozone shield - a layer of the atmosphere composed of ozone gas (O3)
that resides approximately 25 miles above the Earth's surface and
absorbs solar ultraviolet radiation that can be harmful to living
organisms.

poaching - the illegal killing of animals or fish, a great concern
with respect to endangered or threatened species.

pollution - the contamination of a healthy environment by man-made
waste.

potable water - water that is drinkable, safe to be consumed.

salination - the process through which fresh (drinkable) water
becomes salt (undrinkable) water; hence, desalination is the reverse
process; also involves the accumulation of salts in topsoil caused by
evap