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The Coastal Ocean
Essentials of Oceanography
Coastal waters
Relatively shallow areas that adjoin continents
Heavily used for commerce, recreation, fisheries, and waste disposal
Experience dramatic changes in salinity and temperature
Salinity and temperature in the coastal ocean
Estuaries
Estuaries are partially enclosed coastal bodies of waterExamples of estuaries include:
River mouthsBaysInletsGulfsSounds
Formed by a rise in sea level after the last Ice Age
Classifying estuaries by origin
Coastal plain
Fjord
Bar-built
Tectonic
Figure 11-3
Examples of estuaries
Fjord estuary (Norway) Tectonic estuary (San Francisco Bay)
Genesis of a Fjord
Coastal wetlandsCoastal wetlands are saturated areas that border coastal environments
Brackish water conditions
Two most important types of coastal wetlands:
1. Salt marshes (mid-latitudes)
2. Mangrove swamps (low latitudes)
Coastal wetlands: Salt marshes and mangrove swamps
Figure 11-8
The value of coastal wetlands
Coastal wetlands are high biological productivity areas that serve as fish nurseries for many important species
Effectively filter polluted runoff from land
Problem: are viewed as worthless land, so are often replaced with developments (roads, housing, shopping, etc.)
Lagoons
Lagoons are shallow coastal bodies of water separated from the ocean by a narrow strip of land such as a barrier island
Figure 11-9
Mediterranean circulation
The Mediterranean Sea experiences high rates of evaporation
Causes inflow of water at the surface and outflow of high salinity water below
Figure 11-11b
Pollution in coastal waters
Coastal waters are highly affected by pollution because they are:
Heavily used
Close to sources of pollution
Shallow-water bodies
Not as well circulated as the open ocean
Marine pollution: A definition
The introduction by man, directly or indirectly, of substances or energy into the marine environment, including estuaries, which results or is likely to result in such deleterious effects as harm to living resources and marine life, hazards to human health, hindrance to marine activities, including fishing and other legitimate uses of the sea, impairment of quality for use of sea water and reduction of amenities. (World Health Organization)
Main types of marine pollution
Petroleum (oil)
Sewage sludge
DDT (dichlorodiphenyltrichloroethane) and PCBs (polychlorinated biphenyl)
Mercury
Non-point-source pollution
Marine pollution: Petroleum
Oil spills can be caused by:
Tanker accidents
Intentional dumping
Drilling/pumping operations
Figure 11-12
Marine pollution: Petroleum
Petroleum is biodegradable
Many pollution experts consider oil to be among the least damaging ocean pollutants
Data from the 1989 Exxon Valdez oil spill shows the recovery of key organisms
Figure 11-13
Marine pollution: Petroleum
Various processes act to break up and degrade oil in the marine environment
Figure 11-18
Marine pollution: Petroleum
When oil washes up at a beach, it can negatively affect the marine environment
Oil can coat marine organisms and render their insulating fur or feathers useless
Macando Blowout
Gulf of Mexico
Marine pollution: PetroleumDeep-water Horizon Oil Spill (2010) – More appropriately named the Macando Blowout
4.9 million barrels of oil spilled.
Approx. 210,000,000 gallons of oil
Marine pollution: Sewage sludge
Sewage sludge is the semisolid material that remains after sewage treatmentMuch sewage sludge was dumped offshore until laws restricted sewage dumping
Figure 11-21
Marine pollution: DDT
DDT was a widely used pesticide that became concentrated in marine fish
DDT caused brown pelicans and ospreys to produce thin egg shells
Worldwide, DDT has been banned from agricultural use but is still used in limited quantities for public health purposes
Marine pollution: PCBsPolychlorinated biphenyl
Liver damage, cancer, changes in estradiol
PCBs are industrial chemicals used as liquid coolants and insulation in industrial equipment such as power transformers
PCBs enter the marine environment through leaks and from discarded equipment
PCBs can accumulate in animal tissues and affect reproduction
Marine pollution: Mercury and Minamata disease
Mercury has many industrial uses but is extremely toxic
A chemical plant released large quantities of mercury into Minamata Bay, Japan
Residents who ate highly contaminated fish suffered neurological disease and birth disorders (Minamata disease)
Marine pollution: Non-point- source pollution
Non-point-source pollution comes from material washed down storm drains as “poison runoff”
Includes fertilizers (atrizine), pesticides, road oil, and trash
Figure 11-26
Current law regulating ocean dumping
The only substance that is illegal to dump anywhere in the ocean is plastic
Ocean Garbage Patches:
A trash vortex
Approximately twice the size of Texas
At least 100 feet deep
Plastic in the marine environment
Plastic:Does not biodegrade
Floats
Has high strength
Is ingested by and entangles marine animals
Figure 11-28
In groups of two or three:
Design, draw & label the following:An estuary
Movement of water in/out of the estuary from a large body of water.
Some example life forms that would live in the area
3 sources of pollution & the consequences or resolutions to the pollution.
By yourself:1. Draw or describe a made up organism that can be found
in the following zones:a. Euphotic
b. Disphotic
c. Aphotic
d. Hadal
2. At least one must be benthic.
3. The following characteristics/strategies must be included: DSL, counter shading, chromatophores, camouflage, euro/stenothermal, euro/stenohaline, meroplanktonic.
BellworkChange 10 to 25% of the water in your tank. Fill up the tank so there is no visible water line!
If you are not helping with your tank you need to be working on the following:
In groups no larger then 3:
Create a single chart/drawing that includes all of the following in their appropriate locations:
Epipelagic, mesopelagic, bathypelagic, abyssopelagic, hadal, deep scattering layer, estuary, lagoon, barrier island, coastal waters, continental shelf, small-eyed fish, large-eyed fish, blind fish.