FREE ESSAY ON ACID RAIN

ACID RAIN

Acid Rain
What Is Acid Rain 
Acid Rain is a type of air pollution, formed when oxides of sulfur and nitrogen combine
with atmosphere moisture to yield sulfuric and nitric acids, which may then be carried
long distances from a source before they are deposited by rain. This pollution may also
be snow, fog, or a dry form of precipitation. Acid rain is currently a subject of great
controversy because of widespread environmental damage for which it has been blamed,
including eroding structures, injuring crops and forests, and threatening or killing life
in freshwater lakes.The Effect Of Acid RainWhen the environment can't neutralize the acid
rain, damage will occur to forests, crops, lakes, and fish. Toxic metals such as copper
and lead can also be leached from water pipes into drinking water.
Research published in 1996 suggested that forests and forest soils are more susceptible
to the effects of acid rain than previously believed, and recovery from these effects is
very slow. In light of this information, many scientists believe that the 1990 amendments
to the Clean Air Act will not be sufficient to protect lakes and forest soils of the
northeastern United States from further acidification.
Affects In The Aquatic EcosystemsThe interactions between living organisms and the
chemistry of their aquatic habitats are extremely complex. If the number of one species
or group of species changes in response to acidification, then the ecosystem of the
entire water body is likely to be affected through the predator-prey relationships of the
food web. At first, the effects of acid deposition may be almost imperceptible, but as
acidity increases, more and more species of plants and animals decline or disappear. 
As the water pH approaches 6.0, crustaceans, insects, and some plankton species begin to
disappear. 
As pH approaches 5.0, major changes in the makeup of the plankton community occur, less
desirable species of mosses and plankton may begin to invade, and the progressive loss of
some fish populations is likely, with the more highly valued species being generally the
least tolerant of acidity. 
Below pH of 5.0, the water is largely devoid of fish, the bottom is covered with
undecayed material, and the near-shore areas may be dominated by mosses. 
Terrestrial animals dependent on aquatic ecosystems are also affected. Waterfowl, for
example, depend on aquatic organisms for nourishment and nutrients. As these food sources
are reduced or eliminated, the quality of habitat declines and the reproductive success
of the birds is affected. 
Affects Of Terrestrial Plant LifeBoth natural vegetation and crops can be affected from
acid rain. 
It can alter the protective waxy surface of leaves, lowering disease resistance. 
It may inhibit plant germination and reproduction. 
It accelerates soil weathering and removal of nutrients. 
It makes some toxic elements, such as aluminum, more soluble. High aluminum
concentrations in soil can prevent the uptake and use of nutrients by plants. 
Affects of Animal LifeThe effects on terrestrial wildlife are hard to assess. As a result
of pollution-induced alteration of habitat or food resources, acid deposition may cause
population to decline through stress (because of decreases in available resources) and
lower reproductive success.
Affects of Human Life
We eat food, drink water, and breathe air that has come in contact with acid deposition.

Canadian and U.S. studies indicate that there is a link between this pollution and
respirator problems in sensitive populations such as children and asthmatics. 
Acid deposition can increase the levels of toxic metals such as aluminum, copper, and
mercury in untreated drinking water supplies.
Is Acid Deposition Occurring To The Same Extent Across Canada? 
No. Sulphur emissions tend to be concentrated in relatively few locations, while the
sources of nitrogen emissions are widely distributed; however, where they are deposited
depends on more than just where they are produced. Airborne acidic pollutants are often
transported by large scale weather systems thousands of kilometers from their point of
origin before being deposited. In eastern North America, weather systems generally travel
from southwest to northeast. Thus, pollutants emitted from sources in the industrial
heartland of the midwestern states and central Canada regularly fall on the more rural
and comparatively pristine areas of the northeastern U.S. and southeastern Canada. Did
you know!
-That about 40% of nitrogen oxides come from transportation (cars, trucks, buses,
trains), about 25% from thermoelectric generating stations, and the balance from other
industrial, commercial, and residential combustion processes.
-That more than 80% of all Canadians live in areas with high acid rain-related pollution
levels. 
-That it has been estimated that about 50% of the sulphate deposited in Canada is derived
from sources in the U.S.