BIOMES IN THE OCEAN

LIFE ZONES IN THE OCEAN

• HORIZONTAL ZONES–EXTENDING FROM LAND OUT

TO SEA• COASTAL, PELAGIC, NERITIC, OCEANIC

• VERTICAL ZONES–DISTANCE BELOW SEA SURFACE• NEUSTIC, EUPHOTIC, APHOTIC

• BENTHIC ZONE–SEA BOTTOM HABITANTS

HORIZONTAL ZONE

• COASTAL ZONE (INTERTIDAL)– Region where tides expose the sea

bottom for some part of the day. Between High Tide and Low Tide.

– AKA: Littoral, Nearshore, Intertidal–Organizms adapted to harsh

environmental changes

PELAGIC ZONE• LOCATED SEAWARD OF THE

COSTAL ZONE’S LOW-TIDE MARK.

• CONTAINS VAST OPEN WATER OF THE OCEAN.

• TWO SUBDIVISIONS:–NERITIC–OCEANIC

PELAGIC ZONE• NERITIC ZONE–WATER OUTLYING THE CONTINENTAL

SHELF– USUALLY EXTEND TO A DEPTH OF

600FT– SUNLIGHT PENETRATES ENTIRE

COLUMN– GREATEST DENSITY AND DIVERSITY

OF LIFE

PELAGIC ZONE• OCEANIC ZONE– REGION OF THE SEA EXTENDING

FROM THE EDGE OF THE CONTINENTAL SHELF, OVER THE CONTINENTAL SLOPE, AND OVER THE OCEAN FLOOR

–DARKNESS, HIGH PRESSURES– VERTICAL ZONES ARE SIGNIFICANT

HERE

BENTHIC ZONE• THE OCEAN FLOOR• CONTAINS ALL HABITANTS OF

THE SEA BOTTOM• COASTAL, CONTINENTAL SHELF,

DEEP OCEAN…

VERTICAL ZONES• EPIPELAGIC ZONE– PHOTIC ZONE OR SUNLIGHT ZONE

• MESOPELAGIC ZONE–DISPHOTIC ZONE OR TWILIGHT

ZONE• BATHYPELAGIC ZONE– APHOTIC ZONE OR MIDNIGHT ZONE

• ABYSSOPELAGIC ZONE– APHOTIC ZONE OR MIDNIGHT ZONE

• HADOPELAGIC ZONE– APHOTIC ZONE OR MIDNIGHT ZONE

EPIPELAGIC ZONE

• PHOTIC ZONE• ENOUGH SUNLIGHT FOR

PHOTOSYNTHESIS• PRIMARY AREA OF FOOD PRODUCTION• SURFACE TO 200M

MESOPELAGIC ZONE

• DISPHOTIC ZONE (DYSPHOTIC)

• NOT ENOUGH SUNLIGHT FOR PHOTOSYNTHESIS• 200M TO 1000M

MIDNIGHT ZONES

• NO SUNLIGHT• 1000M TO BOTTOM (AROUND

11,000M LOWEST)• LOW DENSITY AND DIVERSITY

OF LIFE

• 1000M – 4000M : BATHYPELAGIC ZONE

• 4000M – 6000M : ABYSSOPELAGIC ZONE

• 6000M – 11000M : HADOPELAGIC ZONE

LIFESTYLES• 3 BASIC LIFESTYLES–PLANKTON–NEKTON–BENTHOS

PLANKTON• FLOATERS OR VERY POOR

SWIMMERS• 2 GROUPS– PHYTOPLANKTON : PRODUCERS,

PHOTOSYNTHESIZERS– ZOOPLANKTON : CONSUMERS

PHYTOPLANKTON

• MUST LIVE IN PHOTIC ZONE

• MOST ABUNDANT IN SHALLOW COASTAL AREAS OR IN UPWELLING ZONES

• BASIS OF OCEANIC FOOD CHAIN

PHYTOPLANKTON

• CYANOBACTERIA• DIATOMS• COCCOLITHOPHORES• DINOFLAGELLATES

ZOOPLANKTON• FORAMINIFERS• RADIOLARIANS• COMBJELLIES• ANTHROPODS• LARVAE

PLANKTON• MEROPLANKTON–SPEND ONLY PART OF THEIR

LIFE CYCLES AS PLANKTON–ARE THE LARVAL STAGES OF

ORGANISMS THAT GROW TO BECOME BENTHIC OR NEKTONIC ORGANISMS

• HOLOPLANKTON–SPEND THEIR ENTIRE LIFE

CYCLES AS PLANKTON

NEKTON• FREE SWIMMERS• MANEUVER ACTIVELY IN WATER

COLUMN• FOUND IN THE WATER COLUMN

FROM SURFACE TO FLOOR

NEKTON• 5 CATEGORIES–REPTILES–MAMMALS–FISH–ANTHROPODS–MOLLUSKS

NEKTON•MARINE REPTILES–TURTLES–SNAKES–CROCODILES–IGUANAS

NEKTON• MARINE MAMMALS–WHALES–SEALS–OTTERS–MANATEES–DOLPHINS

NEKTON• BONY FISH–TUNA–BARRACUDA–EELS–ANGLER FISH

NEKTON• CARTILAGINOUS FISH–SHARKS–RAYS–SKATES

NEKTON•MARINE ANTHROPODS–SHRIMP–CRABS–LOBSTERS–HORSESHOE CRABS

NEKTON•MOLLUSKS–SQUID–OCTOPI–SNAILS–MUSSELS–CLAMS

BENTHOS• BOTTOM DWELLERS• LIVE ON OR ARE ATTACHED

TO BOTTOM• FILTER FEEDERS OR

SCAVENGERS• 2 TYPES–SESSILE : LIVE ATTACHED TO

BOTTOM–VAGRANT : ABLE TO MOVE

BENTHOS - SESSILE

• BARNACLES• SPONGES• CORALS• SEA ANEMONES• OYSTERS• CLAMS• STEAMERS, MMM

BENTHOS - VAGRANT

• CRABS• SEA STARS• SEA CUCUMBERS• SEA URCHINS• BRITTLE STARS

SEA LIFE