Pollution of the
Hydrosphere
Objectives
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Describe the negative effects of sediment pollution
Trace the effects of nutrient pollution in an aquatic
ecosystem
ID sources of toxic organic & toxic inorganic
pollutants
Describe two waterborne illnesses & their sources
Differentiate between types of thermal pollution and
describe the negative effect of each on aquatic
ecosystems
Why is Freshwater Important?
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All organisms require freshwater to live
Less than 1% of all Earth’s water is useable
freshwater
Freshwater is not evenly distributed on Earth
What is Pollution?
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The addition of any
substance that has a
negative effect on water
or on the living things
that depend on the water
Sediment Pollution
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# 1 form of water
pollution
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Occurs when eroding
soil particles are
washed into water by
runoff
Causes of Sediment Pollution
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Exposed
agricultural
fields
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Clear-cut
logging
operations
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Construction
sites
Effects of Sediment Pollution
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Reduces amount of sunlight penetrating water
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Less photosynthesis
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Clogs gills of fish, amphibians, etc
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Some species rely on vision for hunting food
Negatively affects spawning
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Can’t get oxygen
Reduces vision
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Reduces food supply
Fewer eggs…fewer organisms
Make water more shallow
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Upsets ecosystem
Promotes more flooding
Nutrient Pollution
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Increase in the amount
of water soluble
chemicals such as
nitrates & phosphates
in water
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These chemicals act as
fertilizers to aquatic
plants
Sources of Nutrient Pollution
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Fertilizers applied
on lawns, gardens,
& farms
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Leaking septic
systems
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Wastewater
treatment plants
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Detergents
Effects of Nutrient Pollution
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Eutrophication (imbalance in aquatic ecosystem)
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Algal bloom - More algae
More algae dies
Decaying algae decomposed by aerobic bacteria
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Aerobic bacteria – use oxygen
Less oxygen in water = hypoxia
Other organisms die
Decaying organisms build up on bottom, making
water more shallow
Algal blooms clog pipes
Algal blooms clog boat engines
Eutrophication
Eutrophication
Toxic Organic Compounds
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Contamination
containing carbon atoms
Includes: oil, gasoline,
solvents, pesticides,
herbicides
Sources of TOCs
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Oil tanker spills
Underground fuel storage tanks
Lawn maintenance
Agriculture: herbicides, pesticides, manure
Effects of TOCs
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Toxic to living
organisms
Oil can on bird feathers
and animal fur,
restricting their
movement
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Can’t hunt, they’ll die
Affects tourism
Toxic Inorganic Compounds
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Contaminants that don’t contain carbon
Heavy metals: arsenic, mercury, lead
Synthetic industrial chemicals
Sources of TICs
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Poor waste disposal practices
Leaking landfills
Abandoned industrial sites
Effects of TICs
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TICs don’t break down as
readily as TOCs
Can remain in environment for
many years causing:
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Long term health problems
Death
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Bioaccumulation - increase in
concentration of a pollutant
from the environment to the
first organism in a food
chain
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Biomagnification -increase in
concentration of a pollutant
from one link in a food chain to
another
Effects of TICs
Disease-causing Agents
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Viruses
Bacteria
Amoeba
Protozoa
Parasitic worms
Sources of Disease-causing Agents
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Human waste
Animal waste
Waste water
Effects of Disease-causing Agents
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Waterbourne illnesses
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E.Coli
Typhoid
Malaria
Hepatitis
Cholera
Dysentery
Can cause death
Thermal Pollution
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Temperature change to
water
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Causes change in
aquatic environment
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Can cause change in
oxygen level of water
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Cold water holds more
oxygen than warm water
Causes of Thermal Pollution
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Industry uses water. Water
is heated in industrial
process then returned to
river or lake. River or lake
environment is now warmer.
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Dams built on rivers. Water
behind dam builds up…gets
deeper. Deeper water is
colder.
Effects of Thermal Pollution
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Changes in water
temperature are changes to
the aquatic environment.
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Some species are not able
to tolerate the temperature
differences and die off.
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Whole aquatic ecosystem
is affected, changed.