Eutrophications , best for study materials

1. College Of Fisheries Science and Research Centre
(Chandra Shekhar Azad University of Agriculture & Technology, Kanpur)
Campus-Etawah– 206001, Uttar Pradesh
Presented By:-
Vikash Kushwaha
Id No. :CFS-154/19
A
Presentation
on
“EUTROPHICATION”

2. Introduction
• The word eutrophication is derived from the
greek words where eu means well and trophe
means nourishment.
• The process by which a body of water acquires
a high concentration of nutrients, especially
phosphates and nitrates.
• It is a slow-aging process for a water body, but
human activity greatly speeds up the process.
• Occurs naturally over centuries as lakes age
and are filled in with sediments.

3. • It is characterized by excessive plant and algal growth
due to the increased availability of one or more limiting
growth factors needed for photosynthesis such as
sunlight, carbon dioxide, and nutrient fertilizers
(Schindler 2006).
• Promotes excessive growth of algae
• When algae dies and decomposes, high levels of organic
matter is released decomposing organisms deplete
available oxygen of the water, causing the death of other
organisms, such as fish
• Alters the dynamics of a number of plant, animal and
bacterial populations thus, bringing about changes in
community structure.

4. 1. Fertilizer flows into water
causing….
2. Increased plant growth on the surface of
water, causing…..
3. Decreased light in lower levels of water,
causing…
4. Plants in lower levels of water
to die, causing….
5. Decay using up O2 and increasing
CO2,causing…...
6. Death of fish and other animals.
STEPS OF
EUTROPHICATION

5. Sources of nutrients
• Point sources - In point sources the nutrient
waste travels directly from source to water. Point
sources are relatively easy to regulate.
• Eg.
– Sewage treatment plant discharges
– Industrial discharges
• Nonpoint source - Which comes from ill-defined
and diffuse sources.
• Nonpoint sources are difficult to regulate and
usually vary spatially and temporally
• Eg.
– Atmospheric deposition
– Agricultural runoff (fertilizer, soil erosion)

6. • Limiting nutrient : The one in shortest supply
relative to demand. If we add more of that
nutrient the plants/algae will grow.
Phosphorus freshwater
Nitrogen salt & brackish

7. Source-http://www.who.dk/environment/pamphlets

8. Types Of Eutrophication
• Natural Eutrophication – A process that
occurs as a lake or river ages over a period of
hundreds or thousands of years.
• Cultural Eutrophication – A process that
occurs when humans release excessive
amounts of nutrients, it shortens the rate of
aging.

9. Natural Eutrophication

10. Cultural Eutrophication
• The addition of excess
nutrients from a variety of
sources results in the
rapid aging of aquatic
ecosystems.
• During this process the
species composition of
the aquatic community
changes.

11. Category of lake
Lakes are generally categorized by limnologists
according to the degree of nutrient enrichment.
• Oligotrophic lake- A young lake having sandy
bottomed, transparent with little plant life and
low in nutrient input or loading.
• Mesotrophic lake- As the lake becomes older, it
receives nutrients and sediments from the
surrounding drainage basin.

12. • Eutrophic lake- The lake then eventually
becomes nutrient rich and plant growth in the
form of phytoplankton and rooted aquatic
plants, can occur to a level in which the water
becomes undesirable for various uses.
• The overload of nitrogen, phosphorus
and other organic material can result in a
series of 'side effects'.

13. The main effects of eutrophication are:
• Increasing biomass of phytoplankton resulting in 'algal
blooms'.
• Hypoxia (reduced dissolved oxygen content of a body of
water).
• An increasing number of incidents of fish kills.
• The water can have a bad taste, color and odour which has a
negative impact on tourism
• Decline or loss of species biodiversity (commercially
important species may disappear).
• Some phytoplankton species produce toxins that cause severe
symptoms such as diarrhea , memory loss, paralysis and in
severe causes death.

14. Case study in India
Eutrophication in the Lakes of Udaipur city
Fateh Sagar Lake, Udaipur
• Udaipur has faced water scarcity due to its
geographical location.
• In the British regime, Udaipur known as the city of
lakes, and the four large water bodies, Pichhola,
Swaroop Sagar, Fateh Sagar and Badi, remained its
lifelines.
• But the condition of the lakes deteriorated sharply in
the post independence era.

15. • Unregulated and rapid commercialisation
increase the inflow of pollutants.
• The health of the lakes grew down every year.
• Over the last 25-30 years, massive
deforestation and faulty land-use practices
increased inflow of sediments into these
water bodies.

16. • The total outcome of the above activities is
the heavy loading of lake waters with
phosphate and nitrates.
• These two elements basically increase the
growth of Water Hyacinth.
• The lake bottom is also covered with a thick
mat of submerged vegetation.

17. Control measures
• Silt removal programs should be organized on regular
basis.
• Developing reservoir operation policy so as to keep
and maintain the minimum conservation pool level of
at least 10% of the total storage capacity the lakes at all
times.
• The public participation in the campaign of removal of
water hyacinth in the last 25 years.
• Removal of the surface and submerged aquatic weeds
like hydrilla, vallisneria and lemna, the protection of
native fish species & rejuvenation of certain
conservatory type fishery.

19. A case study on
POWAI LAKE

20. LOCATION
• Located in the Powai valley, where a Powai village
once existed.
• Indian Institute of Technology, Bombay and The
National Institute of Industrial Engineering, some of
the premier educational institutions in India are on
the periphery of this lake.
• Luxurious and expensive Housing complexes and
luxurious hotels are developed all around the lake.

21. PROBLEMS
• DECREASE IN AREA
• In recent times, 40% of the lake
has disappeared.
• Accelerated growth of
residential, commercial
establishment
• Quarrying activity in the
catchment area around the lake

22. Water quality deterioration
• Untreated disposal of
sewage and garbage from
nearby residential and slum
colonies have affected the
quality of the water.
• Washing cattle also
deteriorates the water
quality.

23. Management strategies
Two types of management strategies should be
adapted:
Short term practices
Long term strategies
1. Short term practices- to alleviate the affect of
the problem by water column manipulation using
destratifier to prevent water stratification during
summer and autumn.

24. 2. Long term strategies- to reduce sediment
and nutrient inputs to the waterways by
adapting total catchment management
practices in the upstream catchment.
• It is also essential that a multi-disciplinary,
multi-sectoral and multi-focal approach is
adapted to reach the ultimate goal of
sustainable management.

26. Human health impacts
• Harmful algal bloom species have the capacity
to produce toxins dangerous to humans.
• Algal toxins are observed in marine
ecosystems where they can accumulate in
shellfish and more generally in seafood
reaching dangerous levels for human as well
as animal health.
• Several algal species able of producing toxins
harmful to human.

27. Socio-economic impacts
Impact on Recreation and Tourism
• The enrichment of nutrients to an ecosystem
can result in a massive growth of macroalgae.
• The existence of such dense algal growth
areas can inhibit or prevent access to
waterways.
• This decreases the fitness for use of the
water for water sports (swimming, boating
and fishing).

28. Aesthetic impacts
• Algal blooms are unsightly and can have
unpleasant smells.
• Eg.
– When macroalgae or seaweed are decomposed by
anaerobic bacteria hydrogen sulfide is (H2S)
released. This gas is characterized by a very
unpleasant characteristic foul odor of rotten eggs.

29. Economical impacts
• Some specific cases local authorities depend on
eutrophic waters for drinking .
• Infected waters increases the costs of water
treatment in order to avoid taste, odor and toxin
problems in the water.
• Due to the toxins produced by harmful algal
blooms commercial fish and shellfish may
become unsuitable for consumption resulting in
potential economical and financial problems for
the fishing industries.
• In extreme cases beaches are closed due to the
presence of toxic algal blooms.

30. Controls
• Many municipalities have passed legislation
to regulate point-source loading of nutrients,
eutrophication and cyanobacterial blooms but
are still prevalent in surface waters around the
world.
• These strategies have proven to be ineffective,
costly and impractical, especially for large,
complex ecosystems.
Source- www.nature.com/scitable/knowledge/library/eutrophication-causes-consequences-and-controls-in-aquatic

31. • Use of algaecides, such as copper sulfate, is
effective at reducing HABs temporally.
• Copper chelates such as copper citrate , these
can be used in hard and alkaline waters,
where copper sulphate is less efficient.

32. • However, algaecides are expensive to apply
and pose risks to humans, livestock, and
wildlife, in addition to harming a variety of
non-target aquatic organisms.
• Oxidants such as chlorine or potassium
permanganate can also be used
• Biomanipulation - control blooms by
increasing zooplankton populations to
promote heavy grazing of algae.

33. Conclusions
• Eutrophication continues to pose a serious threat to
potable drinking water sources, fisheries, and
recreational water bodies.
• Nutrient reduction can be difficult (and expensive) to
control, especially in agricultural areas where the algal
nutrients come from nonpoint sources.
• Cultural eutrophication and HABs continue to be the
leading cause of water pollution for many freshwater
and coastal marine ecosystems and are a rapidly
growing problem in the developing world.

34. • The demand for freshwater resources is
expected to increase dramatically, protecting
diminishing water resources has become one
of the most pressing environmental issues and
will likely become more complicated as
climate change, species invasions, and
pollution further degrade water quality and
quantity.

35. • Control and management of eutrophication is
a complex issue and will require the collective
efforts of scientists, policy makers, and
citizens to reduce nutrient inputs, to develop
effective, long-term biomanipulation
techniques, and to eventually restore aquatic
communities.

36. References
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