1. “Oceans, Coasts, and Fisheries”
Unit 3
“Oceans, Coasts, and Fisheries”

2. Oceans on the Earth 71% of Earth’s surface is covered by oceans
Composition of ocean water is as follows:
96% water
3.5% salt (mostly NaCl – sodium chloride)
.5% consists of trace amounts of Sulfate, Mg, Ca, K, and Bicarbonate

3. Oceans on the Earth As depth increases, pressure _________. Why?
As depth increases, temperature __________. Why?
As depth increases, salinity _________. Why?
As depth increases, light penetration decreases

4. Movement of Ocean Water
Currents – large volume of ocean water that flows due to changes in density, temperature, gravity, and wind
Horizontal currents: usually due to wind
Vertical currents: due to density, temperature, and gravity

5. Movement of Ocean Water
Upwelling - vertical flow of cold, dense water to the surface; occurs in areas where horizontal currents diverge
Downwelling – vertical flow of warm, less dense water toward the ocean bottom; occurs in areas where horizontal currents converge

6. Movement of Ocean Water
It is important to understand the interconnectedness of air currents (wind) and ocean currents
Air currents affect horizontal ocean currents and horizontal ocean currents affect vertical ocean currents
Therefore, a change in meteorological conditions can affect/change ocean conditions

7. Ocean’s Vertical Zones

8. Ocean’s Zones Continued

9. Ocean Currents Summary

10. Marine Habitats
The ocean contains a great variety of species that include invertebrates and vertebrates
There are two categories of marine habitats:
Benthic: the ocean bottom in either shallow or deep water
Pelagic: the open ocean

11. Marine Habitats
The majority of marine ecosystems are Benthic, but there are also a few found in the Pelagic habitat
Coral Reef
Tide Pool
Salt Marsh
Mangrove Forest
Deep Ocean
Kelp Forest

12. Human Impact on the Ocean
The ocean is used in much the same way as is the lithosphere
Transportation, Resource Extraction (both biotic and abiotic), Tourism etc. are all ways in which people use oceans
As a result of the above-mentioned ocean usage, pollution and overexploitation occurs

13. Pollution and Overexploitation
Pollution – any unwanted substance that is released into the ocean as a result of resource extraction, transportation, or tourism
Overexploitation – is the taking of too many individuals of a marine species thereby making it impossible for those remaining to replenish the numbers lost through fishing
Bycatch – non target marine species are killed as a result of becoming entangled in nets meant to catch another marine species

14. Examples of Pollution & Overexploitation

15. MPA’s & MR’s
Marine Protected Area (MPA): Geographic area with discrete boundaries that has been designated to enhance the conservation of marine resources. This includes MPA-wide restrictions on some activities such as oil and gas mining and the use of zones such as fishery and ecological reserves to provide higher levels of protection.
Marine Reserve: A zone in which some or all of the biological resources are protected from removal or disturbance; encompasses both fishery and ecological reserves.