Life in the Oceans & Life in the Oceans & Ocean ResourcesOcean Resources

Chapter 20.2 & 20.3Chapter 20.2 & 20.3

Ocean Chemistry and Marine LifeOcean Chemistry and Marine Life

Marine organisms Marine organisms depend on depend on

two major factors two major factors

for survival.for survival. Nutrients in Nutrients in

ocean water ocean water SunlightSunlight

Ocean Chemistry and Marine LifeOcean Chemistry and Marine Life

Marine organisms maintain chemical Marine organisms maintain chemical balance of ocean water by:balance of ocean water by: removing nutrients and gases from the oceanremoving nutrients and gases from the ocean returning gases and nutrients to the oceanreturning gases and nutrients to the ocean

UpwellingUpwelling

Deep water is a storage area for nutrients Deep water is a storage area for nutrients needed for life, BUT, most marine needed for life, BUT, most marine organisms live near surface, so…organisms live near surface, so…

Nutrients must return to surface through Nutrients must return to surface through process of upwelling.process of upwelling.

Upwelling: movement of deep, cold, and Upwelling: movement of deep, cold, and nutrient-rich water to the surface.nutrient-rich water to the surface.

UpwellingUpwelling

Marine Food WebsMarine Food Webs

Most organisms live in upper 100 m of water.Most organisms live in upper 100 m of water. Plankton: free-floating, microscopic plants and Plankton: free-floating, microscopic plants and

animals are base of complex food web.animals are base of complex food web. Consumed by nekton and benthos.Consumed by nekton and benthos.

Nekton: all organisms that swim actively in open Nekton: all organisms that swim actively in open waterwater

Benthos: organisms that live on the ocean floorBenthos: organisms that live on the ocean floor

PlanktonPlankton

Larger marine animalsLarger marine animals

Nekton: all organisms that swim actively in Nekton: all organisms that swim actively in open wateropen water• E.g. fish, dolphins, squidE.g. fish, dolphins, squid

Benthos: organisms that live on the ocean Benthos: organisms that live on the ocean floorfloor• E.g. oysters, sea stars, and crabsE.g. oysters, sea stars, and crabs

NektonNekton

BenthosBenthos

Ocean environmentsOcean environments

Two basic environmentsTwo basic environments Benthic zone: bottom region of oceans and Benthic zone: bottom region of oceans and

bodies of fresh waterbodies of fresh water Palegic zone: regions of an ocean or body of Palegic zone: regions of an ocean or body of

fresh water above the benthic zonefresh water above the benthic zone

Ocean zonesOcean zones

Benthic zonesBenthic zones

IntertidalIntertidal Sublittoral zoneSublittoral zone Bathyal zoneBathyal zone Abyssal zoneAbyssal zone Hadal zoneHadal zone

Palegic ZonesPalegic Zones

Zone above the benthic zoneZone above the benthic zone Neritic zone Neritic zone Oceanic zoneOceanic zone

Divided into four zonesDivided into four zones

Ocean ResourcesOcean Resources

Increase freshwater supply by Increase freshwater supply by desalination- the extraction of fresh water desalination- the extraction of fresh water from salt water.from salt water.

Methods of desalinationMethods of desalination DistillationDistillation FreezingFreezing Reverse Osmosis deslinationReverse Osmosis deslination

The Jubail desalination plant in Saudi Arabia is the The Jubail desalination plant in Saudi Arabia is the largest in the world. The plant produceslargest in the world. The plant produces

800 million gallons per day, while generating 5,000 800 million gallons per day, while generating 5,000 megawatts of power. Fresh water is a vital megawatts of power. Fresh water is a vital

environmental resource in the Middle East.environmental resource in the Middle East.

Mineral and Energy ResourcesMineral and Energy Resources

PetroleumPetroleum Found beneath sea floorFound beneath sea floor ¼ of Earth’s oil extracted from offshore wells¼ of Earth’s oil extracted from offshore wells

Trace MineralsTrace Minerals Mg and Br—But to extract is too costlyMg and Br—But to extract is too costly

NodulesNodules Source of manganese, iron, copper, nickel, Source of manganese, iron, copper, nickel,

cobalt, and phosphates—but recovery cobalt, and phosphates—but recovery difficult and expensivedifficult and expensive

Food from the OceanFood from the Ocean

Seafood—important source of proteinSeafood—important source of protein Harvested fromHarvested from

Fishing—important industry Fishing—important industry

but must manage to prevent but must manage to prevent

over-harvestingover-harvesting Aquaculture—the raising Aquaculture—the raising

of aquatic plants and of aquatic plants and

animals for human use or animals for human use or

consumption.consumption.

Ocean-Water PollutionOcean-Water Pollution

Grown worse Grown worse

with growth of with growth of

world population world population

and increased and increased

use of more-toxic use of more-toxic

substances.substances.

Productive coastal areas and Productive coastal areas and beaches are in greatest danger beaches are in greatest danger because they are closest to the because they are closest to the

sourcesource Beach damaged by oil pollutionBeach damaged by oil pollution

Filthy Facts websiteFilthy Facts website

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