Rivers Need Care
The world's rivers have never been under such stress. In the UK
and Ireland, rivers are under huge pressure from human activities.
Rivers and the surrounding land drained by them (catchments) are
very important wildlife habitats. The water itself provides the
environment for fish, plants and animals, while the banks and nearby
land support creatures such as otters, kingfishers and dragonflies
and a variety of water-loving plants. Pollution is the great danger,
which can destroy the balance of this environment.
Where does pollution come from?
There are several sources of water pollution, which work together
to reduce overall river water quality. Industry and agriculture
discharge liquid waste products. Rain as it falls through the air,
or drains from urban areas and farmland, absorbs contaminants.
Acid rain
Rain falling through polluted air absorbs some of the pollutants
as it falls. The main pollutant gases are sulphur dioxide and nitrogen
oxides, which form when fuels are burned. They react with rainwater
to form sulphuric and nitric acids.
On reaching the ground the acid liquid has many effects. It can
release harmful substances such as aluminium and heavy metals from
the soil. These are normally present in an inert, harmless state,
but in acid conditions can turn into compounds poisonous to plant
and animal life. When washed into lakes and streams the aluminium
can kill small water creatures and fish.
Industrial pollution
Many industrial wastes discharged into water are mixtures of chemicals,
which are difficult to treat. Some industrial wastes are so toxic
that they are strictly controlled, making them an expensive problem
to deal with. Some companies try to cut the costs of safely dealing
with waste by illegally dumping chemicals at times and in places
where they think they will not be caught.Agricultural pollution
When organic farm wastes like silage or liquid manure (slurry) escape
into rivers, the amount of oxygen in the water is reduced. Ten thousand
fish died when pig slurry escaped into a tributary of the River
Severn in 1 985.
Nitrate pollution problems occur when too much chemical fertiliser
is applied to the land. The excess runs off and can find its way
into drinking water sources, or can trickle into rivers and lakes.
Some experts believe that high levels of nitrate in drinking water
may pose a threat to health. A European directive states that drinking
water should not contain more than 50 milligrammes of nitrates per
litre of water.
In rivers, streams, ponds and lakes, too much nitrate can create
a 'pea soup' effect. The water becomes clogged with fast-growing
plant life like algae and weeds. This is a major problem especially
in some areas of England such as East Anglia. In problem areas,
some farmers voluntarily control their use of nitrogen.
Protecting rivers and streams
Both the European Union and the British government are concerned
about water pollution. Water quality is protected by many different
laws.
The most important modern legislation is the Water Resources Act
of 1991. It instructs the Environment Agency to police the use of
water in England and Wales. The Environment Agency manages fisheries,
flood defence, navigation, recreation and nature conservation
The Environment Agency protects water resources by issuing licences
for drawing off large volumes of water (abstraction) from watercourses,
and for the discharge of pollutants.
There is evidence that the quality of most rivers in the UK is good
and few give cause for concern. A recent survey, compiled from the
opinions of 140 experts advising the WWF, suggested that UK rivers
are on the whole in relatively good health and are well monitored.
There is however, no room for complacency and river management programs
must be enforced.
UK River Care:
http://www.ukrivers.net
Facts about UK river pollution:
http://www.ukrivers.net/state.html
UK Environmental Agency:
http://www.environment-agency.gov.uk
World River Pollution Issues:
A sample study of areas of the world where pollution is a problem
may be considered from the links below. Use search engines to find
out about the environmental issues relating to other major rivers
of the World.
EcoWorld Website
http://www.ecoworld.com/Water/ecoworld_Water_home.cfm
Columbia River:
http://www.columbiariverkeeper.org/theriver.htm
River Rhine Pollution:
http://library.thinkquest.org/28022/case/rhine.html
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