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Eutrophication Mila Cherneva Atanas Radovanov Stefan Kourdov
10/6
What is eutrophication ?
A process in which an ecosystem collects mineral nutrients
(2)
Occurs in an aging lake or pond (3)
Anthropogenic eutrophication eutrophication caused by human
activity (3)
Often a part of the normal aging process of many lakes and pond
- some never experience it (lack of warmth and light) (2)
Caused a widespread loss of biodiversity in many systems has
some bad outcomes (3)
Causes of Eutrophication
Compounds containing the elements phosphorus and nitrogen
(2)
Sources of anthropogenic phosphorus - sewage discharges,
intensive livestock farms and the spreading of artificial
fertilizers and animal manures onto agricultural land (2)
Sources of anthropogenic nitrogen - gaseous emissions from car
exhausts and power stations and artificial fertilizers applied to
agricultural land (2)
Algal Blooms
Rapid increase in the population of algae in an aquatic
system
May occur in freshwater as well as marine environments
Result of an excess of nutrients (particularly phosphorus and
nitrogen)
Their growth cause for other plants to die
Dead organic matter->food for bacteria-> bacteria
increases-> uses the dissolved oxygen that keeps fish and
aquatic insects alive (1)
Algal bloom in Orielton Lagoon, 1994
http://soer.justice.tas.gov.au/2003/image/527/algal%20blooms/p-algal_bloom_orielton-m.jpg
Causes on People
Consumption of or indirect exposure to harmful algal bloom
toxins may cause illness or mortality (4)
Considerable economic losses to coastal communities and
commercial fisheries (4)
Causes to the Ecosystem (3 main ones)
Decrease in Biodiversity when the nutrients in an ecosystem are
increased, the primary producers are the ones that are benefited
the most. They increase their population and thus prevent the other
organisms from reproducing (become dominant). Also the primary
producers do not give the other species the chance to consume
efficiently the nutrients they need.
Invasion of New Species eutrophication can cause a competitive
release by making abundant a normally limiting nutrient. That may
lead to shifts in the species composition in an ecosystem. The
increase in amount of a nutrient might lead to the invasion of a
given territory by new competitive species that may out-compete
original inhabitant species.
Increase in Toxicity some of the algal blooms that are caused
by eutrophication are being toxic to plants and animals. In order
for them to make their way up the food chain they might produce
toxic compounds which can result in animal mortality.
(Cloem James)
Prevention
regulating agricultural use of fertilizer and animal waste must
be imposed
Policy concerning the prevention and reduction of
eutrophication can be broken down into four sectors: Technologies,
public participation, economic instruments, and cooperation
Creating riparian buffer zones that can prevent the pollutants
from moving from the land (farms, manufactories and etc.) to
flowing bodies of water, such as rivers
Minimizing nonpoint pollution sources of pollutants that spread
chemical compounds indirectly (e.g. through diffusion)
(Cloem James)
Dealing with the Effects
Cleanup measures have a 90% efficiency for eliminating the
pollution
Filtering of the pollutants can help for cleaning up water
Organic Farming organic fertilization; it decreases the levels
of eutrophication in the soil
(Gilbert, Patricia)
The Mississippi River Dead Zone
http://upload.wikimedia.org/wikipedia/commons/b/bd/Mississippi_River_basin.jpg
For the last 30 years the fertilizers used along the
Mississippi River had entered the Gulf of Mexico (9)
This had caused the levels of nitrogen input to triple (9)
There are impacts on the human health
Also, organisms either leave or die in the Dead Zone (9)
Companies in the fishing business, that are worth 2.8 billion
dollars, are threatened by the eutrophication (9)
GRN (Global Recycling Network) is dealing with the industrial
factors along the river (9)
The Problem in the Baltic Sea
http://www.helcom.fi/helcom/en_GB/aboutus/_files/75311642188906561/default/HELCOM_area_50dpi.jpg
On the coast line of the sea live about 85 million people
(7)
The sea itself is isolated by shallow waters and land from
other bodies of water which makes the water exchange 30 years long
(7)
The sea has a relative depth of 53 meters (7)
The large population of people input nutrient and hazardous
substances (7)
There are various salt layers crated on the bottom of the sea
that limit the biodiversity in addition to the eutrophication
effect (7)
HELCOM saves the day through its long-term recovery plans
(8)
What are Harmful Algal Blooms (HABs)? Harmful Algae . N.p.,
n.d. Web. 6 June 2010. .
Cloern, James . "Eutrophication - Encyclopedia of Earth". The
Encyclopedia of Earth. June 4, 2010 .
Gilbert, Patricia. "The Role of Eutrophication in the Global
Proliferation of Harmful Algal Blooms". The Oceanography society.
May 4, 2010 .
Eutrophication in the Baltic Sea. HELCOM Stakeholder Conference
on the Baltic Sea Action Plan Helsinki, Finland, 7 March 2006
http://helcom.navigo.fi/stc/files/BSAP/FINAL%20Eutrophication.pdf
About HELCOM. Helsinki Commission.
http://www.helcom.fi/helcom/en_GB/aboutus/
The Dead Zone. Healthy Waters.
http://www.healthygulf.org/our-work/healthy-waters/the-dead-zone