Transcript Eutrophication Powerpoint

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AP Environmental Science
Chapters 17 and 18
*Eutrophic Lake
* WHAT IS WRONG WITH THIS
LAKE?
1. Process by which a body of water such as
pond, lake, or river has a sudden increase in
algae concentration (high net primary
productivity).
2. Caused by the infusion of excess nitrogen &
phosphorous nutrients from surface water runoff
into local ponds, lakes, river, etc. due to human
activity (anthropogenic causes).
Cultural Eutrophication
* Occasionally, certain conditions—such as an
increase in nutrients in the water—can spur the
algae to reproduce rapidly, causing harmful
“blooms” that can be toxic to ecosystems.
* Prymnesium parvum, a distant cousin of
phytoplankton and giant kelp, is typically found in
the ocean and interferes with aquatic org ability to
respire underwater. Not toxic to humans /terrestrial
animals.
* P. parvum has also recently bloomed in freshwater
environments, where they’ve had devastating
effects, such as fish kills.
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P. Parvum
Highly Toxic
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Nitrogen exists in environment as:
a. Atmosphere (78% N2)
b. Nitrite (NO3)
c. Nitrate (NO4)
d. Ammonia (NH3) or Ammonium (NH4)
e. Lightning
Phosphorous is commonly found from rocks
as PO4.
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3.
Consequences of Cultural Eutrophication
a. Increased algal growth on surface water.
b. Incr. algae causes water to become cloudy
(low turbidity) and decreases dissolved
oxygen in water.
c. Algae can release toxins &interfere with
aquatic species respiration ability.
d. Underwater plants die from low light
attenuation, causing bacteria to decompose
plants.
e. Bacteria use up available dissolved oxygen.
f. Massive fish kills occur.
*Agricultural fertilizer runoff
*Recreational areas such a
golf courses
*Animal Manure
*Fossil fuel
*Industrial Discharge
*Water sewage power
plants effluent
* Excessive Fertilizers from Golf Courses,
Professionally maintained Residential Lawns
* Found naturally occurring in
rocks.
* Found in water systems from
sewage transferred from Sewage
Treatment Plants (STP)
* Each community has standards to
process & neutralize body wastes.
* STP dumps effluent (cleaned
waste water) into local rivers,
lakes, and ponds.
*How can eutrophication
of aquatic systems be
reversed?
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