Photic Pelagic WatersPhotic Pelagic Waters

I. LocationI. Location

A. From surface to 200m A. From surface to 200m (average) (average)

B. Where photosynthesis takes B. Where photosynthesis takes placeplace

II. Environmental II. Environmental CharacteristicsCharacteristicsA. SunlightA. Sunlight

1. Plenty of sunlight1. Plenty of sunlight

2. Where most oxygen for 2. Where most oxygen for planet is producedplanet is produced

3. Wide variety of 3. Wide variety of photosynthetic photosynthetic

organisms organisms

B. TB. T1. Much warmer than deep sea 1. Much warmer than deep sea (for (for the most part)the most part)

2. Changes from day to day 2. Changes from day to day (sometimes within the (sometimes within the

day)day)

3. Has seasonal changes (warm 3. Has seasonal changes (warm during summer, during summer,

cooler during cooler during winter)winter)

4. Varies from place to place4. Varies from place to place

C. PressureC. Pressure

1. Upper photic – not much1. Upper photic – not much

2. Lower photic – bit more, 2. Lower photic – bit more, but but nothing like the deep nothing like the deep seasea

D. OD. O22 - #1 producers of oxygen, - #1 producers of oxygen, so so plentyplenty

E. Food – Not a problem; more E. Food – Not a problem; more food food than anywhere elsethan anywhere else

F. HabitatF. Habitat

1. Surface water is in constant 1. Surface water is in constant motion – waves, tides motion – waves, tides

and and currentscurrents

2. Really no place to hide or rest 2. Really no place to hide or rest – – open wateropen water

3. Can’t rest for long – will be 3. Can’t rest for long – will be eaten or starveeaten or starve

III. Importance of Photic III. Importance of Photic WatersWaters

A. All primary productivity for A. All primary productivity for ocean occurs hereocean occurs here

B. Start of the basis of the B. Start of the basis of the marine food chainmarine food chain

C. Place where humans likeC. Place where humans like

D. Richest part of the oceanD. Richest part of the ocean

IV. Types of OrganismsIV. Types of Organisms

A. A. PlanktonPlankton – organisms at the mercy – organisms at the mercy of the ocean; driftersof the ocean; drifters

1. 1. PhytoplanktonPhytoplankton – planktonic – planktonic plants plants plants at the mercy of the plants at the mercy of the oceanocean a) Basis of the marine food a) Basis of the marine food chainchain

b) Photosynthetic - #1 producers b) Photosynthetic - #1 producers of oxygenof oxygen

c) Most microscopic – diatoms, c) Most microscopic – diatoms, dinoflagellates; Protistas dinoflagellates; Protistas

Diatoms

dinoflagellates

d) Seaweed & kelp – true plants at d) Seaweed & kelp – true plants at mercy of oceanmercy of ocean

e) Without phytoplankton – NO e) Without phytoplankton – NO LIFELIFE

f) Produce more oxygen than f) Produce more oxygen than anything elseanything else

Where did the phytoplankton go!!?

2. 2. ZooplanktonZooplankton – planktonic – planktonic “animals”“animals”

a) Most microscopic – a) Most microscopic – copepods, copepods, larvae of many larvae of many invertebrates invertebrates (crab, shrimp)(crab, shrimp)

b) Some mega plankton – b) Some mega plankton – jellyfish, sunfish (one jellyfish, sunfish (one

of of largest fish in sea)largest fish in sea)

c) Second step in the marine c) Second step in the marine food chainfood chain

Mola mola

http://www.oceanlight.com/spotlight.php?img=3319

B. B. NektonNekton – directed swimmers, – directed swimmers, NOT at the mercy of the oceanNOT at the mercy of the ocean1. Includes all vertebrae 1. Includes all vertebrae

marine marine life, fish, adult life, fish, adult invertebratesinvertebrates

2. Must have special 2. Must have special adaptations adaptations to live in “open” to live in “open” waterswaters

3. Most nekton 3. Most nekton “hydrodynamic” – “hydrodynamic” – streamlined to move through streamlined to move through

water easily, fins water easily, fins retractable, eyes flushed retractable, eyes flushed

with head, powerful tailswith head, powerful tails

4. There is more nekton then any 4. There is more nekton then any other type of animals other type of animals

(except (except insects)insects)

V. Two Very Important V. Two Very Important Phytoplankton Phytoplankton and One and One ZooplanktonZooplankton

A. A. DiatomsDiatoms – unicellular, – unicellular, microscopic microscopic algae algae (phytoplankton)(phytoplankton)

1. Looks like a “petri dish”, 1. Looks like a “petri dish”, usually a golden-brown usually a golden-brown

colorcolor

2. No means of locomotion 2. No means of locomotion

3. Made of silica -> makes 3. Made of silica -> makes siliceous oozesiliceous ooze

4. Feeds over half the marine 4. Feeds over half the marine lifelife

5. Millions upon millions 5. Millions upon millions throughout throughout every oceanevery ocean

6. Probably most important 6. Probably most important organism on this planet organism on this planet

B. B. DinoflagellatesDinoflagellates – unicellular, – unicellular, microscopic algae; microscopic algae; phytoplanktonphytoplankton

1. Has locomotion – flagella -1. Has locomotion – flagella -> > “whip like” projection“whip like” projection

2. Causes 2. Causes red tidesred tides - a massive - a massive killing of marine lifekilling of marine life

a) Dinoflagellates a) Dinoflagellates suddenly multiply in large suddenly multiply in large numbers – millions & millionsnumbers – millions & millions

b) They have a toxin that b) They have a toxin that poison and suffocates marine lifepoison and suffocates marine life

c) In such large numbers, c) In such large numbers, the dinoflagellates tint the water the dinoflagellates tint the water red -> red tidered -> red tide

d) d) DO NOT EAT OYSTERS, DO NOT EAT OYSTERS, FISH, OR CLAMS DURING A FISH, OR CLAMS DURING A RED TIDE!!!RED TIDE!!!

e) Have been known to harm e) Have been known to harm humans humans (Not attacked, but (Not attacked, but swallowed)swallowed)

C. C. CopepodsCopepods – microscopic, – microscopic, shrimp shrimp like zooplanktonlike zooplankton

1. Feed on phytoplankton1. Feed on phytoplankton

2. Second step in marine food 2. Second step in marine food chainchain

3. Filter feeders3. Filter feeders

4. Most have bioluminescence 4. Most have bioluminescence

5. Have adaptations to keep 5. Have adaptations to keep from from sinking into “Death sinking into “Death Zone”, Zone”, below the lightbelow the light

VI. Adaptations of Photic Water VI. Adaptations of Photic Water OrganismsOrganisms

A. Main goal is to stay in the A. Main goal is to stay in the photic zone – fall below will photic zone – fall below will die die (T(T, Pressure, no food), Pressure, no food)

B. Many have “projections” – fins, B. Many have “projections” – fins, hair, spines, etchair, spines, etc

1) Increases surface volume 1) Increases surface volume of “body”of “body”

2) Slows sinking rate2) Slows sinking rate

C. Body shapeC. Body shape1) Most are flat – easier to 1) Most are flat – easier to

stay stay afloatafloat2) Streamlined – move 2) Streamlined – move

through through water fast;water fast;3) Extra fat – 3) Extra fat – blubberblubber -> help -> help

larger animals stay larger animals stay afloatafloat

4) “Air” bladder – many fish, 4) “Air” bladder – many fish, allows them to stay allows them to stay “suspended”“suspended”

D. ColoringD. Coloring

1) Counter-shaded -> dark on 1) Counter-shaded -> dark on top, light on bottom, top, light on bottom,

blends blends in with environmentin with environment

2) Striping – dark, light banded 2) Striping – dark, light banded – blends with wave action– blends with wave action

3) Plankton – usually brownish 3) Plankton – usually brownish or clear (hard to see)or clear (hard to see)

4) Some brightly colored – 4) Some brightly colored – “coral “coral reef” blendingreef” blending

5) Nekton – generally silver, 5) Nekton – generally silver, graygray

E. SpeedE. Speed

1. Nekton – usually very fast, 1. Nekton – usually very fast, if if not will be eaten or starvenot will be eaten or starve

2. Plankton don’t have to 2. Plankton don’t have to worryworry

F. DefenseF. Defense

1. Being big or very small1. Being big or very small

2. “Swim in schools”2. “Swim in schools”

3. Being fast3. Being fast

4. Coloring - hard to see4. Coloring - hard to see

VII. The Benthos OrganismsVII. The Benthos OrganismsA. A. BenthosBenthos – organisms that live – organisms that live

in in or on the bottom of the or on the bottom of the oceanocean

B. Includes – crabs, clams, sea B. Includes – crabs, clams, sea stars, barnacles, snails, octopus, stars, barnacles, snails, octopus,

some fish, coral, etc…some fish, coral, etc…

C. Three TypesC. Three Types

1) 1) EpifaunaEpifauna – live – live on topon top of of the ocean floorthe ocean floor

2) 2) InfaunaInfauna – lives – lives inin or or burrow into the sediments burrow into the sediments of the ocean floorof the ocean floor

3) 3) SessileSessile – permanently – permanently attached; like barnaclesattached; like barnacles

D. Most benthos on continental D. Most benthos on continental shelfshelf

E. Harsh environmentE. Harsh environment

1) Constant changes in salinity 1) Constant changes in salinity levelslevels

2) Constant and heavy waves, 2) Constant and heavy waves, currents & tide actioncurrents & tide action

3) Constant change in water T3) Constant change in water T4) “Home” constantly moving 4) “Home” constantly moving

(unless on rocks)(unless on rocks)

F. AdaptationsF. Adaptations1) Excellent burrowers – can 1) Excellent burrowers – can

dig dig in sediments very in sediments very fastfast

2) Usually have a “shell” for 2) Usually have a “shell” for protection (keep protection (keep

from from getting getting crushed – waves, crushed – waves, seds)seds)

3) Cryptic coloring – can 3) Cryptic coloring – can change change or “patterned” or “patterned” after after sedimentssediments

4) Some have great “stick ‘um” 4) Some have great “stick ‘um” power – cling to rocks, etc,,power – cling to rocks, etc,,

5) Special feeding lots of food in 5) Special feeding lots of food in this area; mostly tiny “particles”this area; mostly tiny “particles”

a) a) filter feedersfilter feeders -> “rake in” -> “rake in” food particles (usually food particles (usually

with with antenna or “hands”)antenna or “hands”)

b) b) siphon feederssiphon feeders -> “siphon” -> “siphon” in in water with food water with food particlesparticles

c) c) detritus feedersdetritus feeders – feed on – feed on small particles of small particles of

decaying decaying mattermatter

VIII. Miscellaneous VIII. Miscellaneous A. The photic zone is a vast areaA. The photic zone is a vast areaB. Includes many species of B. Includes many species of

organismsorganismsC. Variety of adaptations, colors, C. Variety of adaptations, colors,

sizes, etc…sizes, etc…D. 99% of all studies in the ocean D. 99% of all studies in the ocean

are in the photic zoneare in the photic zoneE. Still many unanswered questionsE. Still many unanswered questionsF. Without the photic zone, there F. Without the photic zone, there

would be NO LIFE!would be NO LIFE!

IX. Importance of the photic IX. Importance of the photic waterswatersA.A. Start of food chainStart of food chain

1. 1. primary productivityprimary productivity – – energy energy that comes from that comes from

photosynthesisphotosynthesis

2. #1 producers of 2. #1 producers of photosynthesis – photosynthesis – phytoplanktonphytoplankton

3. 20% of the phyto sink below 3. 20% of the phyto sink below the photic zone & diethe photic zone & die

4. the sinking of dead organisms 4. the sinking of dead organisms is is called called detritusdetritus

5. 90% of food for benthic comes 5. 90% of food for benthic comes from detritus from detritus

6. about 95% of all marine “food” 6. about 95% of all marine “food” begins in the photic zonebegins in the photic zone

7. Without phytoplankton = no life7. Without phytoplankton = no life

B. Nutrients not found readily in B. Nutrients not found readily in photic zonephotic zone

1. Nutrients needed to help 1. Nutrients needed to help go go through photosynthesisthrough photosynthesis

2. most nutrients found below 2. most nutrients found below photic zonephotic zone

3. need a nice mixing of 3. need a nice mixing of waterswaters

a. a. upwellingsupwellings – a current – a current that that brings nutrients from brings nutrients from

the deep to the surfacethe deep to the surface

b. b. winter mixingwinter mixing – surface – surface waters become colder & sinkwaters become colder & sink

1) this forces nutrients to 1) this forces nutrients to surfacesurface

2) excellent winter mixing in Gulf 2) excellent winter mixing in Gulf of Mexico – very productiveof Mexico – very productive

3) the tropics & the polar regions 3) the tropics & the polar regions – not very good mixing– not very good mixingleads to poor primary leads to poor primary productivity – but clear productivity – but clear

waterswaters

C. Factors that affect primary C. Factors that affect primary productivityproductivity

1. Types of organisms – more 1. Types of organisms – more phytoplankton = more phytoplankton = more

“food”“food”

2. Sunlight – needed for 2. Sunlight – needed for photosynthesisphotosynthesis

3. T3. T & seasons – affects & seasons – affects amount of nutrientsamount of nutrients

4. Amount of nutrients – can’t 4. Amount of nutrients – can’t live on sunshine alonelive on sunshine alone