(Redirected from Stagnant water)
'Water stagnation' occurs when
water stops flowing. 'Stagnant water' can be a major
environmental hazard.
Dangers
Malaria and
dengue are among the main dangers of stagnant water, which can become a breeding ground for the
mosquitoes that transmit these diseases.
Stagnant water can be dangerous for drinking because it provides a better incubator (than running water) for many kinds of
bacteria, and other
parasites.
Causes and prevention
Stagnant water may be classified into the following basic, although overlapping, types:
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Water body stagnation: stagnation in
lakes,
lagoons,
rivers, etc.
★ Surface and
ground water stagnation
★ Trapped water stagnation. The water may be trapped in human artifacts (discarded cans, plant pots, tires, dug-outs, roofs, etc.), as well as in natural containers, such as hollow tree trunks, leaf
sheaths, etc.
To avoid ground and surface water stagnation, drainage of surface and subsoil is advised. Areas with a shallow
water table are more susceptible to ground water stagnation due to the lower availability of natural soil drainage.
Excessive watering may cause ground or surface water stagnation.
Life that may thrive in stagnant water
Some plants prefer flowing water, while others, such as
lotuses, prefer stagnant water.
Bacteria
Various
anaerobic bacteria are commonly found in stagnant water.
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Denitrifying bacteria
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Purple bacteria (both sulfur and non-sulfur)
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Leptospira
Fish
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Northern snakehead fish
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Siamese fighting fish
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Pygmy gourami
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Spotted barb
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Lepisosteidae (gar)
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Walking catfish

Mosquito
larvae in stagnant water
Insects
Stagnant water is the favorite breeding ground for a number of
insects.
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Mosquito larvae
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Fly maggots
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Dragonfly nymphs
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Nepidae (water scorpions)
Other
★ A number of species of
frogs prefer stagnant water.
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Algae
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Biofilm
★ Some species of
turtles
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Mata mata
Miscellanea
Pools of stagnant water have historically been used in the processing of
hemp and some other
fiber crops, as well as of
linden bark used for making
bast shoes. Several weeks of soaking makes
bast easily separable due to bacterial and fermentative processes.
See also
★
Water pollution