1. Human Dependence and Modification
Ocean Systems
Human Dependence and Modification

2. Our Oceans Over 70% of our planet is ocean.
97% of the water on Earth is ocean water
Ocean systems –systems which affect weather and climate, ocean currents, coral reef and artificial reef ecosystems and marine food webs.

3. Earth’s Water Distribution

4. How humans depend on oceans
Create a circle map to brainstorm how humans depend on the ocean.
Human Dependence on oceans

5. How humans depend on oceans
Food – fish and shellfish
Transportation – both travel and shipping
Recreation (boating, scuba, jet skis)
Minerals – salt, sand, gravel, manganese, copper, nickel, iron and cobalt
Drilling for crude oil
Removing carbon and providing oxygen (C-cycle)
Regulates Earth’s climate – transfers heat
Medicines for fighting disease.

6. Oxygen Production
50-85% of the worlds oxygen production comes from marine producers called phytoplankton in our oceans.
Carbon Cycle
CO2 is taken out
O2 is given off

7. Oceans impact on Climate
Ocean currents transfer heat great distances around the world that helps regulate Earth’s climate.

8. Global Warming
The average increase in Earth’s global surface temperatures.
More CO2 is in the atmosphere and absorbed in the ocean making it more acidic.
Ocean water absorbs most of the heat from the sun causing ice caps to melt and ocean temperatures to increase.

9. Human Activities that modify ocean systems
Positive activities:
Artificial reefs, education programs, reducing, reusing and recycling, controlling global warming, fishing regulations, etc.
Negative activities:
Overfishing/Overharvesting
Shipping
Global warming
Coastal development
Deforestation
Siltation/sedimentation flowing into oceans
Pollution

10. Coral Reefs
Natural underwater ocean structures made up of living coral and their remains of limestone.
Provide humans with food, recreation, and medicines.
Are at risk due to overfishing, ocean warming, pollutions and siltation due to coastal development.

11. Artificial Reefs
Human-made underwater structures that act as coral reefs to help promote marine life.

12. Benefits of Artificial Reefs
Artificial reefs provide complex, durable and stable homes for many fishes and marine invertebrates
Scientists use artificial reefs as platforms for rigorous ecological experimentation.
Fishery managers sometimes use artificial reefs to help buffer the effects of overfishing and environmental damage.
Artificial reefs attract anglers and divers and provide a significant fiscal boost to local economies.

14. Tidal Power
Tidal energy in the form of hydropower that converts the energy of tides into useful forms of power mainly for electricity.

15. Tidal Power

16. Tidal Power

17. Migratory path

18. Overfishing/Overharvesting
Fishing or harvesting too much marine life that it negatively effects the ecosystem.
Doesn’t allow fish time to reproduce and replace.

19. Shipping
In theory, shipping can be safe and profitable for economies around the world.
However, problems may occur
Oil spills
Dumping of waste water
Chemical accidents
Water and air pollution
Disrupting natural ocean environments
Killing marine wildlife

20. Algae Bloom
An excessive growth of algae (red to bright, neon green to more blue-green) in water that occurs naturally or as a result of an excess of nutrients (phosphorus and nitrogen) from organic pollution.
Agriculture and
Urban runoff has
a high Phosphorus
and Nitrogen
content.

21. Algae Blooms
Most algal blooms are harmless, but certain types of algae may pose a risk to humans, animals and water quality. Algae and algal blooms are generally not considered harmful unless they are capable of producing toxins and you come in direct contact with them.
Blue-green algae that form have been known to produce a wide array of neurotoxins, liver toxins, cell toxins and skin irritants

24. Factors Contributing to Algae Blooms
Excess nutrients from runoff (e.g. phosphorus or nitrogen) from Agriculture and Urban sources.
Fertilizer and sewage
Intense Sunlight
Low-water levels or low-flow conditions
Calm water (low-wind conditions)
Warmer temperatures

25. Zebra Mussels

26. Zebra mussel video