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EUTROPHICATION

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					EUTROPHICATION




       NATALIA KORCZ EPM I
 What is the eutrophication?

Addition of artificial or non-artificial
nutritious substances into water basins.
Especially biogenic elements like nitrates
and phosphates. This elements create
excessive production of algae’s biomass.
It appears as so-called ‘algal bloom’.
Nitrates (NO3-)
•are water-soluble (they dissolve
easily in water), and are commonly
applied to agricultural fields as
fertilizer.
Phosphates (PO43-),
•are not water-soluble; they do not
usually dissolve in water. However,
they do adhere to soil particles.
        Types of eutrophication
• Natural- goes very slow, from moment in
  which lake starts to exist. It is caused mainly
  by changes of climate. Natural eutrophication
  is minimal and imperceptible for human.

• Anthropogenic –(civilization, artificial) it is
  connected with public utilities; sewage,
  deforestation and intensive farming.
         Causes of eutrophication
• natural run-off of nutrients from the soil and the weathering
  of rocks
• run-off of inorganic fertilizers (containing nitrates and
  phosphates)
• run-off of manure from farms (containing nitrates, phosphates
  and ammonia)
• run-off from erosion (following mining, construction)
• discharge of detergents (containing phosphates)
• discharge of partially treated or untreated sewage (containing
  nitrates and phosphates)
http://www.google.pl/imgres?imgurl=http://library.thinkquest.org
         Effects of eutrophication

•   increase in plant and animal biomass
•   increase in growth of rooted plants, e.g. reeds
•   increase in cloudiness of water
•   increase in rate of sedimentation
•   decrease in species diversity
•   change in dominant biota (e.g. carp replace trout and
    blue-green algae replace normal algae) and an
•   increase in the frequency of algal blooms.
•    High fluactions of concentration of oxygen and pH
•   Formation of anaerobic conditions
•   Intensive colouring and smell
Lake Rankala, Kolhapur (India) : Eutrophic due to high
            phosphorous concentrations




    http://www.engr.colostate.edu/~harshad/documents/Projects/NLCP/lake.html
The Gulf of Mexico




   http://www.marietta.edu/~biol/biomes/mangroves.htm
Matilda Bay, Swan-Canning Estuary during February 2000
 Consequences of eutrophication

• the water may become unsuitable for drinking
  even after treatment
• decrease in the amenity value of the water
  (e.g. it may become unsuitable for water
  sports such as sailing)
• disappearance of commercially important
  species (such as trout)
 Chemical consequences of anoxic
            conditions
 When plants and algae die their remains are consumed
  by aerobic bacteria. This results in a reduction of the
  level of dissolved oxygen. Eventually, often near the
  bottom of a lake, virtually no oxygen remains and the
  water is said to be anoxic. Under these conditions
  anaerobic bacteria flourish. Anaerobic bacteria often
  produce foul-smelling compounds such as
   – hydrogen sulphide (H2S)
   – thioalcolohs (RSH) and
   – ammonia (NH3).
• resulting in the water becoming extremely unpleasant
http://www.saawinternational.org/enviromentandhealth.htm
http://www.saawinternational.org/enviromentandhealth.htm
Schematic Diagram Showing effect of algal bloom
on water quality
         Did you know…?


  Eutrophication plagues more than half the
lakes in Europe and Asia, 41 percent of those
  in South America, and 28 percent in North
                  America.
      Eutrophication prevention
• planting vegetation along streambeds to slow
  erosion and absorb nutrients
• controlling application amount and of fertilizer
• directing waste water away from lakes to
  rivers and the sea researching use of biological
  controls.
• reducing the use of phosphates as builders in
  detergents
                             Bibliography


•   http://www.google.pl/imgres?imgurl=http://library.thinkquest.org
•   http://www.engr.colostate.edu/~harshad/documents/Projects/NLCP/lake.html
•   http://www.marietta.edu/~biol/biomes/mangroves.htm
•   http://www.saawinternational.org/enviromentandhealth.htm
•   http://www.scienceclarified.com/El-Ex/Eutrophication.html
•   http://www.sciencedaily.com/articles/e/eutrophication.htm
•   http://www.lenntech.com/eutrophication-water-bodies/introduction.htm
•   http://ec.europa.eu/environment/water/water-nitrates/pdf/eutrophication.pdf

				
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posted:10/12/2011
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