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Law of the Sea

Treaties regarding ownership andexploitation of the marine resourcesratified during the last 50 years

Truman extended U.S. control of themarine resources from the shoreline toa depth of 100 fathoms

1958 and 1960 Geneva Conventions onthe Law of the Sea resulted in a treaty

that placed the control of the sea bed,sea bed resources, and waters of thecontinental shelf under the country thatowns the nearest land

1982 U.N. Draft Convention on the

Law of the Sea

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1982 U.N. Draft Conventionon the Law of the Sea

Territorial waters extend seaward for 12nautical miles from the coast and are underdirect jurisdiction

An exclusive economic zone (EEZ) thatextends for 200 nautical miles offshore orto the edge of the continental shelf (if thatis farther), giving nations the right toregulate fishing, mineral resources,pollution and research

The right of vessels to free and innocentpassage outside of the territorial waters andthrough international straits that lie withinterritorial waters

That all private exploitation of mineral

resources beyond the EEZs must beapproved by the U.N. International SeabedAuthority and that part of the revenue fromthe resources will be shared with thedeveloping nations

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EEZ

The U.S. has the worlds largestEEZ because of the large areassurrounding various islandpossessions and states

The U.S.s EEZ is 30% larger thanthe land area of the U.S.

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Exclusive Economic Zones

(EEZ)

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U.S. EEZ

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Mineral Resources Petroleum, Oil, and Gas

Gas Hydrates Sand and Gravel

Manganese Nodules Cobalt Deposits

Phosphorus

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Petroleum Complex mixture of hydrocarbons

Hydrocarbon = combination of hydrogen and carbon with various

amounts of nitrogen and metals Oil as it comes from the ground is

called petroleum or crude oil Composition varies greatly depending

on the geologic history Smaller hydrocarbons are less dense

and lighter Oil can be separated into various

densities by distillation because oils of different densities evaporate at differenttemperatures

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Petroleum, Oil and Gas Hydrocarbons derived from

sedimentary rocks, which weredeposited in quiet, productiveregions with anoxic bottom waters in

which the remains of phytoplanktonaccumulated Deep burial resulting in high

temperature and pressure convertedthe organic remains to hydrocarbons

Initially oil, but higher temperaturesand pressure, methane is generated

Pressure forced the oil and gas fromthe source rock into water-filledporous and permeable strata above

Oil and gas accumulated, forming alarge deposit usually sandstone

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Oil and Gas Deposits

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How oil is found

Location of possible accumulationsof oil and gas can be determinedusing seismic reflection andrefraction methods to determine theconfiguration of rock layers

This only indicates the potential totrap oil and gas, not if oil and/or gasis present

Large reserves in ANWR and Marsin Gulf of Mexico (but smallcompared to U.S. consumption)

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Gas Hydrates

Unusual hydrocarbon deposits thatconsist of frozen water moleculesentrapping a single methanemolecule

Occur in polar sedimetns and indeposits of the continental slopebetween the depths of 300 and 500m where cold water is in contactwith the sea floor

Deposits contain incredibly largeamounts of gas, but no economicalmethod for its recovery at present

North Carolina deposits 350 x

annual energy consumption of theU.S. (6.6 billion barrels/yr)

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Sand and Gravel

Natural aggregates of unconsolidatedsediment with grain size greater than0.065 mm in diameter

Sand and gravel accumulate in highenergy environments where strongcurrents and/or waves prevail

Relict sediments on continental shelf from when sea level was lower

Materials used for construction of

roads and building Materials used to replenish beaches Mining sand and gravel threatens

both the benthic and pelagiccommunities and introduces largeamounts of material into suspension

Only 1% of sand and gravelpresently taken from offshore

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Sand and Gravel

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Manganese Nodules

Composed of about 20-30%

manganese, 10-20% iron oxide,1.5% nickel, and less than 1%copper, zinc and lead

Locally the nodules are veryabundant

Presently, no economical method of recovering them from the deep sea

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Cobalt Deposits Sides of many seamounts and islands

are enriched in cobalt between thedepths of 1000-2500 m

Cobalt is a strategic metal used inmaking jet engines

U.S. cannot produce sufficient cobaltto meet its needs

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Phosphorus

Phosphorus is required for growthby all organisms

Phosphate deposited generally formon submarine terraces where coastalupwelling generates highproductivity

Organic wastes and remainsaccumulate in the sediment and asthey decay they release phophoruscompounds, which precipitate asphosphate nodules

Nodules grow at the rate of about 1-20 mm/1000 yr

World consumption of phosphate is

about 150 million tons/yr Known supplies should last until

2050

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Living Resources

Fishing

Whaling Mariculture

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Fishing

Two types of fish are fished Pelagic live in water column Groundfish live on sea floor

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Fishing

Most of the ocean is sparselypopulated because of low nutrientavailability

Major fish production areas arecoastal waters and regions of upwelling

Because they are economic tocapture, major commercial fishes arethose which form large schools

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Ocean Fisheries

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Fishing Methods

To locate the fish Sonar Scouting vessels

Airplanes Satellites

Nets

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Drift Nets Controversial, because they capture

everything too large for the net andneedlessly kill many organisms

1989 U.N. Convention for theProhibition of Long Drift netsprohibits drift nets longer than 2.5km Compliance is voluntary Impossible to enforce

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Fishing Sustainability World ocean fish production appears

to have leveled at between 80-100million tons/yr

Maximum sustainable catchestimated to be 100 million tons/yr

Currently the expense to fishexceeds the profit from the sale of fish Fishing industries survive only through

government subsidy

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Overfishing

Removing a living resource from thesea faster than it can replace itself

If continued long enough, the

resource will collapse Overfishing is possible today

Technology has made it easier to locatelarge schools of fish and to directfishing fleets to those locations

Mismanagement of policies related tosustaining fish populations

Fishermen resist quotas and misreportcatches

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Fishing Harvests

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Maximum Sustainable Yield

Theoretical maximum amount of fish that can be removed from apopulation without significantly

interfering with the populationsability to renew itself

Based on biological factors such aspopulation dynamics, food webs,

and spawning success, and thefishing effort required to produce agiven catch

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Problems with determining

a maximum sustainableyield Under-reporting the amount of fish caught Natural fluctuations of populations due to

predation and food supply The inherent difficulty in determining the

size of fish populations The unknown impact of discard fish (those

returned to the sea because they are too

small or of poor quality) on the population Politics frequently result in altering the

scientifically determined maximumsustainable yields to meet political ends

Should be replaced by precautionary

principle, which is to avoid anything whichmay damage or negatively impact a fishery

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Mariculture Marine agriculture or fish farming Finfish, shell fish, or algae Currently, about of the fish

consumed has spent part of its life inmariculture

For some species, this percentage ishigher

For mariculture to be economicallyviable, the species must be Marketable Inexpensive to grow Trophically efficient

At marketable size within 1to 2 years Disease resistant

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Mariculture vs. Fishing

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The Human Presence in theOcean

Pollution

Hydrocarbons natural and spills Municipal and Industrial Wastes Ocean Dredging and Mining

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Pollution

Introduction by man, directly orindirectly, of substances of energyinto the environment, resulting in

deleterious effects such as harm toliving resources, hazards to humanhealth, hindrance of marineactivities, including fishing,impairing quality for use of seawater and reduction of amenities

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Pollutants

Manufacturing,transportation,

agriculturalfertilizers, and

pesticides

NoneSyntheticChemicals

Municipaleffluents,

agriculturalfertilizers

Rivers,upwelling,

atmosphere,bacterial

decomposition

Nutrients

Industrial andmunicipaleffluents

Volcanoes,rivers, sedimens,

weathering of rocks

Heavy Metals

Transportation,production,

aerosols

Seeps, rivers,volcanoes,

atmosphere,bacteria

Hydrocarbons

HumanSource

NaturalSource

Pollutant

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Extent of Pollution

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Studying Pollution

Need to have a baseline from whichto measure mans impact upon theenvironment, because some of what

is considered to be pollution may beoccurring naturally and not causedby man

Pollutants are eventually broken

down by various oceanographic andbiological processes

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Parts of the ocean wherepollution is conentrated

Sea floor bottom of ocean Accumulation on bottom by settling or

by becoming attached to particleswhich settle

Mainly affects benthos

Pycnocline density gradientbetween surface and deep ocean Accumulation because pollutants are

too light to sink through dense bottomlayer

Often occurs in estuaries

Neuston layer air-water interface Mainly affects plankton

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Hydrocarbons

Only a small fraction of the oil in thesea comes from major oil tankeraccidents 31% from contaminated rivers 32% from tanker release as they pump

their bilges, incomplete burning of fuel,and general ship traffic

13% from leakage at coastal refineries 20% from natural oil seeps and

atmospheric fallout

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Transportation Routes forCrude Oil

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Hydrocarbon Fates

Altered in the environment Spreading Lighter than water so it floats Spreads to be film on top

Drift by currents and wind

Evaporation Light portion evaporates Dissolution

Soluble portion dissolves

Emulsification Heavy portion Forms into a water-oil mixture without

dissolving Globules which eventually form tar balls,

which wash ashore or sink

Sedimentation Attaches to particles and sinks to bottom

Biodegradation Broken down into CO 2 by bacteria Some ingested by larger organisms

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Hydrocarbon Fates

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Municipal and IndustrialEffluents

Humans produce over 20 billion tonsof wastes each year

Much of that is disposed of in theocean Most wastes from farmland, cities,

and industrial areas Most wastes enter ocean through

rivers All bodies of water have a natural

capacity to clean themselves of acertain amount of pollution

Dense populations can overwhelmthat

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Pollution Distribution

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Pollutant Fates

Diluted as it enters the oceandependent on waves and currents

Pollutant behavior depends on

temperature, density, and stability A contaminant plume is formed

upon release

Plume increases in size with distance

as the pollutant is diluter

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Pollutant Fates

Particulate matter will settle out,larger particles settle out first andclosest

Some material will concentrate at

pycnocline Influence of pollution decreases with

distance from the source

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Biota Distribution near

Outfall At the source

the bottom will consist of sludge No infauna

Farther from the source Dwarfed individuals

At even greater distance Fauna will be unusually abundant due

to large amounts of nutrients Fauna forms dense masses

At a great distance Fauna unaffected by the pollution

Normal density and normal size of individuals

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Municipal and Industrial

Wastes Sewage

Messy sludge of organic and inorganiccompounds

Heavy metals Elements such as lead, mercury,

cadmium, arsenic, and copper thatnormally occur in trace amounts butbecome toxic in larger dosages

Artificial biocides Man-made toxic chemical compounds

that do not occur naturally

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Bioaccumulation andBiomagnification

Bioaccumulation The process whereby organisms retain

and concentrate a toxic material withintheir body

Biomagnification The process whereby a toxic material

increases in concentration with eachtrophic level of a food chain

Results from bioaccumulation at eachtrophic level

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Sewage

Human waste is a major componentof sewage Organic matter Inorganic nutrients (nitrates and

phosphates) Pathogens

Disease-causing organisms such as bacteria,viruses and parasites

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Results of Sewage

If sufficient nutrients are released, aphytoplankton bloom can occur As dead phytoplankton sink to the bottom and

decompose, an excessive demand on oxygenoccurs

Biological oxygen demand (BOD) Water becomes hypoxic or anoxic Process called eutrophication

Resulting low oxygen content will killmost organisms on the bottom and in theaffected water column As herbivores are killed, there is less grazing More phytoplankton survive to reproduce and

generate an even greater BOD Eventually the food chain can be decimated

Eutrophication observed in lakes,

embayments, and even on sections of thecontinental shelf

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Heavy Metals

Normally added to the ocean insmall amounts through theweathering of rocks and volcanic

activity Manufacturing and industrial

processes greatly increase theamount of heavy metals released

Mercury, especially methyl mercury,is highly toxic because it is notbiodegradable Stored in the fatty tissues Damages the central nervous system

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and fishing

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Narragansett Bay

Hypoxic and anoxic conditions

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Artificial Biocides

Halogenated hydrocarbons ororganochlorines are common DDT

PCB Not biodegradable Remain for a long time

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DDT

Highly toxic Banned in most of the western world Use continues in some countries

Sprayed on crops and soil, muchwashes into rivers

Some remains airbornecontaminating rain and snow orsettling into the ocean

Has been detected in the muds of thedeep ocean and in the ice of Antarctica

Large lens off Los Angeles Miles in diameter, > 1 m thick

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PCB

Used in production of electricalequipment, paints, and adhesives

Released into the environment by

incineration and unregulateddisposal

Have been found throughout theocean environment

Hudson contaminated by GE

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Agricultural Wastes

Fertilizers and animal wastes washedoff fields into rivers

Eventually flow into ocean Act as fertilizer in ocean Cause eutrophication

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Ocean Dredging

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Ocean Dredging

80-90% of the material dumped atsea each year comes from dredging

If dredged material is clean, it is lessof a problem If material is dumped slowly, many

benthic organisms can work their wayto the surface through the new layer of sediment

If material is dumped too rapidly, theyare buried and killed

If the material is different than theoriginal, a different group of organismsmay colonize the area

Clean dredgings can be used toreplenish beaches

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Contaminated Dredge

Sediments Represent an initial and long-term

source of pollutants Come from harbors and rivers,

Dredging the contaminatedsediments reintroduces pollution intothe water at the site of the dredging

Dumping the sediment releasespollution at the dumping site

As the dumped sediment compacts,contaminated pore water escapes andcontaminates the water column

Storms and currents disturb thesediment and reintroduce pollution

To minimize reintroduction,contaminated sediment is frequentlycapped

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Ocean Mining Mining will most likely be

accomplished with a hydraullicpumping system that will vacuumwater, sediment and organisms from

the sea floor and bring them to thesurface

Most of these organisms will die

Large areas of the sea floor will be

disrupted and stripped of life Sediment released at the surface will

create a massive sediment plume If it remains suspended, it will reduce

photosynthesis due to lower light frothe increased turbidity

Rapid sinking could bury organisms

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Name the 5 oceans