1. Pollution of the Hydrosphere
Chapter 28
Pollution of the Hydrosphere

2. Sediment Pollution
Rapid introduction of sediments into water ecosystems due to runoff
Sources include:
exposed agricultural fields
clear cut logging
construction sites

3. Effects of sediment pollution
Hurts aquatic organisms
reduces the amount of photosynthesis that can occur in water
reduces the ability to absorb oxygen
may clog gills

4. Nutrient Pollution An increase in nutrients in an aquatic ecosystem
Leads to a rapid increase in growth of plants and algae
Algal bloom is a rapid increase in algae due to the introduction of nutrient fertilizers into an ecosystem.

5. Eutrophication
Nutrient pollution due to an increase in nitrates and phosphates
Caused by use of fertilizers, leakage from septic/sewage systems

6. Nutrient Pollution (Eutrophication)
Sources are:
Detergents
Nitrogen compounds
Runoff from streets and lawns
Fertilizers from agriculture
Discharges of sewage treatment plants and septic tanks

7. Effects of Eutrophication
Hurts aquatic organisms
Reduces amount of light for photosynthesis
Increases the amount of dying algae
Results in bacterial growth that depletes oxygen in the water
Decreased dissolved oxygen creates hypoxic (low/no oxygen) conditions, toxic to living organisms

8. Toxic Organic Compounds
ORGANIC (natural) = contains CARBON!
Examples: Oil, Gasoline, Pesticides
Hurts aquatic organisms:
heavy oil pollution in the water can be deadly

9. BP Oil Spill (2010) Gulf of Mexico
In April 2010 an explosion on the Deep water Horizon drilling rig killed 11 men and sent millions of gallons of oil gushing into the Gulf of Mexico

10. Toxic Inorganic Compounds
It includes synthetic industrial chemicals and heavy metals, such as:
Lead, Mercury, Arsenic
Sources include:
poor waste disposal
toxic chemicals infiltrating and contaminating groundwater
May be worse than toxic organic compounds because they can remain deadly for years and usually are not broken down naturally.

11. Disease-Causing Agents
Specific organisms that cause or spread diseases, such as viruses and bacteria.
Waterborne illnesses is a type of disease caused by an organism that lives in water.
Some examples are:
Typhoid
Malaria
Hepatitis

12. Disease-Causing Agents
Wastewater: polluted water that is unfit for drinking or for introduction into the environment because it has been previously used and contaminated
Wastewater affects organisms
Can contaminate shellfish and other fish
Humans may eat contaminated fish and develop health problems

14. Thermal Pollution Caused by a change in temperature.
The temperature of the water and the amount of dissolved oxygen is an inverse (opposite) relationship.
Nuclear power causes thermal pollution
Water used for cooling towers increases the temperature of surface water when released
Aquatic animals need a constant temperature to survive

16. Thermal Pollution
Construction of dams causes thermal pollution by lowering water temperature
The temperature of the river drops about 10 degrees
Native fish cannot tolerate the temperature change.

17. Test Your Knowledge
1. The most widespread pollution is.. Sediment Pollution 2. The enrichment of fertilizers in an aquatic ecosystem is called... Nutrient Pollution 3. Runoff from a construction site can result in.. Decreased Photosynthesis

18. Test Your Knowledge (cont.)
4. Leaking septic systems located around lakes and ponds can cause.. Nutrient Pollution 5. A rapid increase in the population of aquatic plants is known as.. Algal Bloom 6. Increasing amounts of nitrates and phosphate fertilizers in water cause.. Eutrophication

19. Test Your Knowledge (cont.)
7. As the temperature of the water increases, what happens to the level of dissolved oxygen within the water? It Decreases 8. What is the main source of waterborne illnesses? Wastewater 9. PCB’s are an example of what? Toxic Inorganic Compounds

20. Test Your Knowledge (cont.)
10. An increase or decrease in water temperature caused by human activity is known as what? Thermal Pollution