ed alkaline, and anything
measured below 5.6 is considered acid precipitation; note - a pH of
2.4 (the acidity of vinegar) has been measured in rainfall in New
England.

asbestos a naturally occurring soft fibrous mineral commonly used in
fireproofing materials and considered to be highly carcinogenic.

biodiversity - also biological diversity; many species, diverse in
form and function, at the genetic, organism, community, and ecosystem
level; loss of biodiversity reduces an ecosystem's ability to recover
from natural or man-induced disruption.

catchments assemblages used to capture and retain rainwater and
runoff; an important water management technique in areas with limited
freshwater resources, such as Gibraltar.

DDT (dichlorodiphenyltrichloroethane) a colorless, odorless
insecticide that has toxic effects on most animals; the use of DDT was
banned in the US in 1972.

defoliants chemicals which cause plants to lose their leaves
artificially; often used in agricultural practices for weed control,
and may have detrimental impacts on human and ecosystem health.

deforestation the destruction of vast areas of forest (e.g.,
unsustainable forestry practices, agricultural and range land
clearing, and the over exploitation of wood products for use as fuel)
without planting new growth.

desertification - the spread of desert-like conditions in arid or
semi-arid areas, due to overgrazing, loss of agriculturally productive
soils, or climate change.

dredging - in general, the practice of deepening an existing waterway;
more specifically, a technique used for collecting bottom-dwelling
marine organisms (e.g., shellfish) or harvesting coral, often causing
significant destruction of reef and ocean-floor ecosystems.

driftnet fishing done with a net, miles in extent, that is generally
anchored to a boat and left to float with the tide; often results in
an over harvesting and waste of large populations of non-commercial
marine species (by-catch) by its effect of "sweeping the ocean clean".

ecosystems ecological units comprised of complex communities of
organisms and their specific environments.

effluents waste materials, such as smoke or sewage, which are
released into the environment, subsequently polluting it.

endangered species a species that is threatened with extinction
either by direct hunting or habitat destruction.

freshwater - water with very low soluble mineral content; sources
include lake