A presentation on Eutrophication.

1. Eutrophication

2. Eutrophication
excessive richness of nutrients in a lake or other body of
water, frequently due to run-off from the land, which causes
a dense growth of plant life.

3. Natural Eutrophication Cultural Eutrophication
Types of Eutrophication

4. Natural Eutrophication
Natural eutrophication is the process by which lakes gradually age and become
more productive.

6. Cultural Eutrophication
Cultural eutrophication occurs when man speeds up the aging process by
allowing excessive amounts of nutrients in such forms as sewage, detergents,
and fertilizers to enter the ecosystem.

8. Sources of Eutrophication
Point Sources Non Point Sources

9. Point Sources
Pollution that comes from a discrete source. Directly attributable to one influence.
Nutrients waste travels directly from source to water. Point sources are relatively easy to
regulate

10. Industrial Source
industrial wastewater discharges nitrogen and stormwater runoff are some of the industrial
sources of nutrient pollution. Pulp and paper mills, food and meat processing, agro-
industries, and direct discharge of sewage from maritime vessels are some of the larger
sources of industrial nutrient pollution.
Power Plant
specific emitting points through which through which wastes are emitted
Sewage Treatment Plant
Treatment process releases oxides of Nitrogen and Phosphates of in effluents, which drain
to waterbodies

11. Non Point Sources
Pollution that comes from the diffuse source. Non point source are difficult to regulate
and usually vary spatially and temporarily

12. Urban Source
Municipal wastewater treatment plants wastewater discharges, nitrogen leaching from below-
ground septic tanks, and stormwater runoff are some of the urban source of nutrient pollution
The most prevalent urban source of nutrient pollution is human sewage, though its
importance varies by region and country. Sewage is estimated to contribute 12 percent of
riverine nitrogen input in the United States
Agriculture Source( Chemical Fertilizers, Manure, Aquaculture)
A portion of the volatilized ammonia is redeposited in waterways through atmospheric
deposition. Phosphorus, which binds to the soil, is generally lost through soil erosion from
agricultural lands. an oversupply of manure means that it is applied to crops more than is
necessary, further exacerbating nutrient runoff and leaching. Aquaculture (fish farming) is
another growing source of nutrient pollution
Fossil Fuel
When fossil fuels are burned, they release nitrogen oxides (NOx) into the atmosphere. NOx
contributes to the formation of smog and acid rain. NOx is redeposited to land and water
through rain and snow

13. Causes of Eutrophication
The sources of Eutrophication are indirectly responsible for eutrophication. But the main
responsible are showed on the next

14. Causes of Eutrophication
discharge of
detergents
Run-off of inorganic
fertilizer
Run-off from erosion
Natural run-off
nutrients from the
soil and the
weathering of rocks
Run-off of manure
from farms
discharge of partially
treated or untreated
sewage

15. Steps of Eutrophication

16. Excessive Nutrients Enter into Waterways
Through runoff, fertilizers from farms or lawns wash off into the waterbody, where the process all begins

17. Nutrients Help Develop Plant Growth
The nutrients of the fertilizers (nitrogen and phosphorus) help quickly grow not only plants, but algae too

18. Algal Blooms Occur
With the high levels of nutrients in the water, algae grows VERY quickly, which leads to the overgrowth of
algae called algae bloom

19. Plants Die
the algal bloom on the surface of the water blocks sunlight to the plants at the bottom of the pond/lake. As
plants require light for photosynthesis and this light is blocked, the plants die.

20. Algae and Plant Die and Decomposed by Bacteria
The algae eventually die and bacteria decompose both the dead plants and the dead algae, further using
up the oxygen in the pond/lake.

21. Fish And Other Aquatic Life Forms Die

22. At this point the pond/lake is anoxic (no oxygen in the water) and only
bacteria/algae which do not need oxygen to survive are left.

24. Examples of Eutrophication

25. Potomac River
Beginning in the 19th century, wastes from factories, farms and residential area deteriorated the water quality causing
severe eutrophication. President Abraham Lincoln tried to escape the stench of the river and another President
Lyndon Johnson dubbed it as a “National Disgrace”. However the govt. took initiatives to save the river.

26. Lake Erie
Lake Erie is the 4th largest lake in the USA and 11th largest globally. Millions depend on the lake for drinking
water and recreation. It’s also a vital fishery. But it has a long history of environmental damage, that continues
today with a resurgence of toxic algae bloom. Even though the researcher, farmers and nearby residents team
up to tackle the problem there’s has been signs of re-eutrophication since 2013

27. Gulshan Lake
The lake has been declared by the city corporation as being "Ecologically Critical Area" in 2001. Direct dumping of
sewage and water runoff had increased the pollution of the lake. The lake has also experienced an algal boom
which has further reduced the oxygen available, harming the aquatic life

28. Impacts of Eutrophication
Ecological Impact Human Health Impact Economic Impact

29. Ecological Impact
Algae Bloom
Harmful Algae Bloom
Mortality of fishes, birds and other mammals
Water Pollution
Dissolved Oxygen Depletion
Species Biodiversity Decreases

30. Human Health Impact
Amnesic Seafood Poisoning
Muscular paralysis
Difficulty in breathing
State of Shock
Gastrointestinal symptoms (diarrhoea,
vomiting and abdominal pain)
Difficulty in breathing

31. Economic Impact
Financial Loss of Fishing Industry
Recreation and Tourism
Hefty Costs of Water treatment

32. How to Control Eutrophication

33. Improvement of the purifying performance of waste water treatment plants
Installing tertiary treatment systems to reduce nutrient concentrations
Implementation of effective filter ecosystems to remove nitrogen and phosphorus present in the run-off
water (such as phyto-purification plants)
Shellfish in estuaries and using predatory fishes

34. Reduction of phosphorous in detergents
Removal and treatment of hypolimnetic water (deep water in contact with the sediments) rich in
nutrients since in direct contact with the release source
Oxygenation of water for restore the ecological conditions, reducing the negative effects of the eutrophic
process, such as scarcity of oxygen and formation of toxic compounds deriving from the anaerobic
metabolism
oxygenation of water for restore the ecological conditions, reducing the negative effects of the
eutrophic process, such as scarcity of oxygen and formation of toxic compounds deriving from
the anaerobic metabolism;

35. Thank You
Feel Free to Ask Any Question