REVIEW OF OCEAN ZONES

What Ocean zone is closest to the shore? Intertidal Zone Why do we call the shoreline an INTERTIDAL

zone?

**Because it is where land and sea meet between low and high tide

**They must survive great changes in temperature, sunlight, & salinity.

(view page c114 in textbook for more info on this)

High tide, low tide, why do we care anyways… This allows for a great variety of life

here! The area between high tide and low tide

are called the intertidal zone In order for the tide to reach areas that are further back on the shore, the tide must be higher then normal

All about tides Tides are the rising and falling of water level in

the ocean…lowest at low tide The moon and sun contribute to the tides.

HOW? Gravitational Pull

The gravity is always acting/working on the sun and moon. As the moon’s gravity is pulling on Earth, the Earth’s water bulges creating tides.

What comes after the intertidal zone? Neritic Zone We find the GREATEST AMOUNT of

ocean life in the NERITIC zone.

But why?

Because the great amount

of nutrients and temperature

What is PLANKTON?

PHYTOPLANKTON ZOOPLANKTON

Plant-like microbes that make their own food.

Animal-like organisms that eat other organisms.

Plankton microbes are the most abundant life in the ocean.

PHYTOPLANKTON ZOOPLANKTON

Converts sunlight and carbon dioxide into food and oxygen. Greek and Latin word “photo” meaning light

in fact it converts about as much CO2 (carbon dioxide) into oxygen as all land plants combined.

Important source of oxygen that you are breathing right now algae plant-like protists

Greek and Latin word “zo” meaning animal

Zooplankton eat phytoplankton and then become food for other organisms animal-like protists krill jellyfish

PHYTOPLANKTON ZOOPLANKTON

Plankton microbes have incredibly fast growth & life cycles

these microbes are the most important food & oxygen source on the planet!

Think about why?

What happens when there’s too much algae?

Plankton and algae are nutrients, food, and chemicals that support life.

When Phosphorus and nitrogen levels increase, it causes an increase in algae blooms known as eutrophication.

Eutrophication is usually a slow process where the overabundance of algae covers the surface area of a body of water

This blocks the sun from penetrating all the way through and reducing available oxygen levels in the given area

2 habitats here in the neritic zone:

CORAL REEFS KELP FORESTS

Coral Reefs Kelp Forests

In warm tropical regions Built up limestone

deposits from small organisms called corals

Corals depend on a certain type of algae for food needs, algae uses sunlight to produce food

Only exist in areas where sunlight reaches

In cold waters Type of seaweed that

attaches itself to ocean floor

Appox 130 feet tall Uses sunlight to produce

food Only found in waters

near shore Provides habitats for

many animals

The intertidal and neritic zones have lots of life because

of the Sun! It kicks off PHOTOSYNTHESIS…so all the

producers (sea plants & phytoplankton autotrophs) can make their own food!

And subsequently, become food for all others in a food web.

Continental shelf – the gradual sinking on continental crust into water

Continental crust- the area where continental crust meets oceanic crust resulting in a deep drop since the density of the crust differs greatly

Got Fish? UPWELLING

• Upwelling is the process in which water from the depths (deeper parts of the ocean) moves up to the surface (coast) because the direction the wind is pushing the water.

• This brings nutrients to the surface of the water and makes great fishing spots for fishermen

Got Fish? OVERFISHING BYCATCHING

Overfishing is when so many fish are caught, that the population can’t reproduce fast enough to replace them.

Caused by Mass Fishing and Commercial Fishing.

We catch three times more fish than we need.

By-catching is when commercial fishermen catch a portion of animals that they didn’t originally intend on catching in their nets, which eventually get thrown back into the ocean in most case injured or dead

Sometimes the by-catch numbers are greater than the portion of fish actually intended to be caught

What’s life like farther down… Deep Ocean

The Benthic zone is the deepest, coldest, and darkest part of any body of water.

It has very little if any sun. Most Benthic zones have NO SUN! Since it is located so far down, the pressure increases so

much that people could EXPLODE and not as many marine animals swim/survive in this area.

COOL FACT! Most of the Benthic Zone is unexplored…because humans can’t survive the crushing pressure and vastness of the ocean… but we do learn from

Deep ocean exploration & technology tells us!

Despite the pressure, darkness, lack of air, and temperature scientists have developed tools to help explore the ocean

submarines & other submersibles are used to explore sea life

Deep ocean exploration & technology tells us!

Sonar Waves (sound waves) map sea floor. Vibrations travel down and reflect (bounce back) from the

sea surface or animals to tell us things such as depth

Life exists even in the deep ocean

But how?

Life exists even in the deep ocean!

CHEMICAL ENERGY from Hydrothermal Vents hydrothermal vents are underwater volcanoes that seeps

methane gas and other nutrients from the earths interior into the water, providing that food and heat that plants need/use

This process is known as chemosynthesis

HOW?