lO:36AlO:36A ROCKY COASTAL ZONES ROCKY COASTAL ZONES

U.S. western coastal zones are more mature because seasonal" changes are less. The greatest limiting factor is predation.

U.S. eastern coastal zones are less mature because of temperature changes that cause seasonal population changes. The greatest limiting factor is climate.

 

Rocky coasts are characterized by:

abundant food supply with good light

- tides produce hours of flooding in cool water followed by desiccation (drying out) and high temperatures.

- tidal pools are created and emptied- temperature and salinity fluctuations- very distinct zonation worldwide- wave shock

Wave action cuts rocks into sea caves, cliffs and sea stacks that provide shelter. Competition for these limited living spaces is high.

Sea stack Sea cave

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Inhabitants must find a place toattach or be crushed between waves and rocks. Methods of attachment include cement, byssus threads, holdfasts, muscular and tube feet, and boring.

Adaptations also include symbiosis and reproductive strategies, like hermaphrodites and organisms that change sex. The rocky coastal communities' succession has a predictable _pattern that is often controlled by sea urchins. Grazing urchins remove algae from rocks.

New communities can then begin because one group doesn't over populate the area.

Pioneer stage - bacteria and algae Juvenile - protozoa and worms Mature - barnacles, rockweed, mussels, starfish and sea urchins

_collectively these animals became known as fouling communities because of their harmful effects on ship's hulls, docks, pilings, and the smell they create at low tide.

10:37A10:37A  PHYLUM ARTHROPODAPHYLUM ARTHROPODA

It is numerically the largest phyla, and literally means jointed foot.

Class: Crustacea - crab, shrimp, barnacle, and lobster (Florida specie has no claws)

1. Jointed appendages have a variety of specialized functions.2. The body is covered by an exoskeleton made of chitin.Advantage: good protection, muscles attach to it for strength_Disadvantage: heavy and does not grow - animal must molt (shed) exoskeleton and becomes very vulnerable to predators

3. The body has 2 segments - a cephalothorax covered by the carapace and the abdomen.4. Meroplanktonic larvae don't compete with adults for food; Metamorphosis provides a gradual change to adult life.5. An open circulatory system contains a blue pigment called hemocyanin to transport oxygen from the gills to the body.

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, ...unlike the red pigment hemoglobin, their blood carries copper instead of iron. It makes an excellent medium for long-term", laboratory test because it will not support bacterial growth.

 

6. They have a ventral nerve cord with a well-developed brain and compound eyes. Neurosecretory cells control molting, color changes, food storage and hormones.

  PHYLUM ECHINODERMATA PHYLUM ECHINODERMATA (means .spiny skin)(means .spiny skin) ex: starfish, sea

urchins, sand dollars

1. endoskeleton of calcium carbonate plates2. bilaterally symmetrical larvae3. water vascular system instead of muscles is a big advantage in predatory situations4. highly regenerative - can eviscerate5. separate sexes; external fertilization

Why are they considered advanced?

Sea star

Sea urchin

Sand dollar

Seastar feeding on barnacle

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Why are they considered simple?

1. Light-sensitive eyes located at the end of each ray do not provide vision because there is no brain nor head. 2. They have reduced internal organs - no respiratory, circulatory, excretory nor nervous system. 3. Adults have pentamerous (5) radial symmetry . 4. Respiration is by diffusion through the skin.

_Starfish are scavengers and eat a variety of organisms. The starfish can open a clam shell a few centimeters wide. Then by inverting its stomach into the shell, the clam is digested and absorbed. Missing parts from injuries or evisceration are quickly replaced. Any. portion of the central disk will regenerate a _ new starfish - a fact that oyster fishermen learned too late!

10:38A TIDES10:38A TIDES

Tides are extremely long waves caused by the gravitational attraction of the Moon and the Sun on Earth. They are also affected by the: 

1.shape and depth of the ocean floor 2. latitude (greater pull at equator3. volume of water

The Earth and Moon revolve around each other and rotate on their axes.

Earth's rotation = 24 hours (one day)moon's rotation = 24 hours and 50 minutes (lunar day)

Tides occur 50 minutes later every day because of the rotation time difference.

At high tide (flow), the Moon pulls water out toward it. Centrifugal force pulls water out on the opposite side - causing a tidal bulge.

As the Earth turns, locations moveout of the center of gravity and low tides (ebb) result.

Low tide

High tide

Tidal range - difference between high and low tide volume ex:

When the Earth, Moon and Sun are orbiting in a linear arrangement, the Moon is in either the new or full stage.

_With the Sun and Moon pulling together on the water, tides are increased - called a spring tide.

_At quarter phases, the Moon pulls opposite and equal to the Sun - resulting in lower tides called neap tide.

This shows the different views of the Moon from Earth during a lunar month's revolution of 28 days.

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Aphelion -- the point on its orbit when the Earth is farthest from the sun

Perihelion -- the point on its orbit when the Earth is closest to the sun

July

95 million miles away

January

95 million Miles away

Tides are greater in North America in the winter because th Earth is slightly closer to the Sun in winter.

Tides are also greater at times during The month when the moon and earthAre closer together

252,000miles away

233,000 miles away

Monthly revolution of Moon and Earth

MixedSemiDiurnal

Diurnal

_Frequency is how often tides occur. There are some exceptions but basically there are 3 types: 1. semi-diurnal = 2 equal high and low tides per day each 6 hours and 12 1/2 minutes apart ex: east coast of U.S. 2. Diurnal = 1 high and 1 low tide per day each 12 hours and 25 minutes apart ex: Gulf of Mexico, S.E. Asia 3. Mixed = 2 high and 2 lows of unequal range at 6 hrs. and 12 1/2 minutes apart ex: west coast of U.S.

10:39 A WAVES10:39 A WAVES

Crest

Trough

Most wavesAre causedBy wind

1) Height is measured from crest to trough. 2) Wavelengths are measured from the crest of one wave to

the crest of the next wave.3) Period is the amount of time across a wavelength.To do this, measure the time from when the first crest hits I until the next crest hits to same point.4) Velocity is the speed of the wind (velocity = distance/timeTo do this, measure the wavelength, then divide by the period. 5) Fetch is distance over which the wind blows in one direction

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Swell is when bigger waves over take smaller waves.

7) Curl is the circular pattern of waves caused by wind blowing over the crest of a wave.

Why do waves break?

Water particles move in circular patterns. When the depth of the water is less than 1/2 the wavelength, the wave hits bottom. The length rolls over to become the height and the wave breaks.

10:39C10:39CTypes of waves (not caused by Types of waves (not caused by wind):wind):

1. Seiche waves are without a crest or trough. They cause the rocking motion in bays and marinas.

2. Rogue waves are caused by the collision of two water masses with different densities. They appear suddenly and may capsize boats.

3. Tsunamis are the result of earthquakes on the ocean _ floor. They are very long, low invisible waves in the open ocean. By the time they reach the shore and break, the wave height may be 100 ft. high and may travel at 400 miles/hour.

The largest tsunami recorded measured 210 feet, about 18 stories above sea level, when it reached Siberia's Kamchatka Peninsula in 1737.

In 1883, Krakatau was completely destroyed by a tsonami and volcano that killed 37,000 people.

4. Tidal waves are a combination of storms and high spring tides. They are very different from a tsunami.