Is an organized system of relationship between plants and animals
in the aquatic environment.
Who investigates the physical, chemical and biological
properties of ocean waters, ocean currents and ocean basins.
A. Pelagic Division
B. Benthic Division
A. PELAGIC DIVISION
This division embodies all the waters of the oceans and their
adjacent salt water bodies.
1. NERITIC ZONE
Extending offshore to the edge of the continental shelf to a depth
of 600 ft.
Rich in plant nutrients, especially the phosphates and nitrates.
The water is more variable in density and in chemical content than
2. OCEANIC ZONE
Has well-populated upper, lighted, 660 ft. stratum, deeper,
relatively dark, and sparsely populated layers.
Characterized by great pressure, animals modified for life in
darkness and under great pressure, and very few bottom animals.
The water is usually very transparent
B. BENTHIC DIVISION
The division of the marine environment embraces the entire
ocean floor, both coastal bottom and deep sea bottom, properly
termed the littoral and deep-sea systems, respectively.
1. LITTORAL ZONE
Area located between the high and low tide marks.
Animals living are adapted to periodic exposure to
air and sun as the tides eeb and flow
Most animals are motile
2 TYPES OF LITTORAL ZONE
a. EULITTORAL ZONE
This is probably the richest zone of the marine ecosystem
with respect to numbers and kinds of organisms.
Factors that changes in this environment are:
These variations are reflect in shapes movements, tolerance and life
histories of the characteristic animals and plants.
5 MAJOR KINGDOMS IN THE OCEAN
-no internal cell membranes
-planktonic or benthic
-recycle organic material
Protista: foraminifera, diatom,
-planktonic or benthic
-planktonic, benthic, eat or
• Abundant in the intertidal zone
• Not as diverse as on land
• Important in decomposition
• Plants that grow
attached to the sea
– Red, brown, and
– Advanced plants of
salt marshes and
• Only found in shallow
areas where bottom
is in the photic zone
2. DEEP-SEA SYSTEM
COMPONENTS OF MARINE ECOSYTEM
( classification by lifestyle)
A. PLANKTON ORGANISMS
C. NEKTON COMMUNITY
D. BENTHOS ORGANISMS
E. CORAL REEFS
F. MANGROVE SWAMPS
A. PLANKTON ORGANISMS
These organisms are small, mostly microscopic and have a
little or no power of locomotion, being distributed by water
This includes all the following plants, such as the small algae,
fungi and sargasum weed.
The most important in the economy of the sea are the Algae,
Diatoms and Dinoflagellates. They are the major producers in
Are microscopic, unicellular
plants and some of them form
They possess characteristic shell
composed of translucent silica,
and have a great variety of form
Possess one or more
chromophores, ranging in color
from yellow to brown.
Occurs as fossil, siliceous shell
deposits, called “diatomaceous
earth” and as a living producers in
practically all habitats of the
broad marine ecosystem.
They are found floating in water,
attached to the bottom, on larger
plants, on animals, and as spores,
enclosed in Arctic ice.
Phytoplankton organisms are more abundant in natural –
rich coastal waters than in offshore oceanic waters.
They are the primary producers upon which large and
small marine animals feed.
Possess whip-like flagella
that provide a slight degree
modifications that indicate
adaptation to environment
Organisms are the floating or weakly swimming animals,
which include the eggs and larval stages as well as adult forms.
PRINCIPAL KINDS includes
PROTOZOA such as Foraminifera and Radiolarian
CRUSTACEA such as Ostracods and Copepods
MOLLUSKS and also the eggs and early developmental stages
of most of the non- planktonic organisms in the sea.
• Small herbivores (plant eaters) that filter
diatoms from the water
• Molt their outer skeleton as they grow
• About the size of a grain of rice
• Migrate vertically seasonally
• Single celled, microscopic organisms
• Calcium carbonate shells - Carbonates
• Benthic forms outnumber the pelagic
• Their shells are porous and protoplasm
streams from inside the shell to engulf and
C. NEKTON COMMUNITY
They are actively swimming animals in marine ecosystems.
They comprise adult stages of such familiar forms as crabs,
squids, fish and whales.
Are airs breathing animals that live both on land and the sea.
Some of them are snakes, turtles, crocodiles and lizards.
D. BENTHOS ORGANISMS
They are relatively few kinds and numbers of animals on the deep-
They are mainly mud dwellers, possessing characteristic
structures permitting life in a quiet, dark, muddy environment
where food is scarce.
They are snails, mussels, clams, oysters, sea anemones, sea urchin,
sea cucumbers and starfish.
Epifauna - live on the bottom
Infauna – live within the bottom sediments
Note: fauna signifies animals not plants
E. CORAL REEFS
Are the habitats of marine organisms, like sea hares, sea fans,
sea anemones and nudibranchs.
Are important source of fish and other fishery products.
Are massive deposits of limestone that have been produced by
coral animals belonging to Phylum Cnidarian, Order Scleractinia
with major additions from calcareous algae and other organisms
that secrete calcium carbonate.
CERTAIN FACTORS THAT FAVORS THE
DEVELOPMENT OF CORAL REEFS
1. Temperature above 18 degrees Celsius.
2. Water depth shallower than 50 meters.
3. Constant salinity greater than 30 but less than 36 parts per
4. Low sedimentation rates.
5. Sufficient circulation of pollution-free water.
6. Pre-existing hard substrate.
THREE TYPES OF CORAL REEFS are;
1. ATOLLS are circle reefs enclosing a lagoon, horseshoe-shaped
ridges of reefs.
2. BARRIER REEFS along continents.
3. FRINGING REEFS are very common around tropical high islands
and sometimes border the main coastline.
FACTORS THAT LEAD TO THE DESTRUCTION
OF CORAL REEFS
1. Pollution from oil, sewage, heavy metals and thermal discharge,
have caused the destruction of fringing reefs.
2. Destructive fishing activities such as blasting, dragging nets over
reefs and the use of cyanide.
3. Reef gleaners break corals by walking over the reef at low tide to
gather food and swimmer damage coral with their fins.
4. Tourists sometimes remove live corals and reef animals for souvenir.
Indiscriminate anchoring tourists’ boats over coral reefs have caused
huge destruction to frequently visited areas.
F. MANGROVE SWAMP
Help to form Island and extend shores. (LAND BUILDER)
Are among the few emergent land plants that tolerate the salinities
of the open sea.
TWO TYPES OF MANGROVE
1. RED MANGROVE
Form the outermost zone.
Has an extensive deposition of mud and silt.
Provide surfaces for attachment of marine organisms.
Its seed sprout while still on the tree, the seedlings drop off
and float in the water where well-develop roots may take hold,
perhaps to start anew island.
2. BLACK MANGROVE
Forms a zone nearer shore.
Its roots stick up the mud like branch of asparagus.
Mangroves are not only important in extending coasts
and building islands, but also in protecting coasts from
excessive erosion which might otherwise be produced by
fierce tropical storms.
PROBLEMS OF MARINE ECOSYSTEM
1. Nature-induced stresses
2. Man-induced stresses
1. NATURE-INDUCED STRESSES
By water movement and geological and biological
a. Water movements due to typhoons or cyclonic
b. Biological factors such as competitions and predation
are known to cause reef deterioration.
2. MAN-INDUCED STRESSES
Are siltation, overfishing in shallow coastal waters,
destructive fishing, logging and conversion of mangroves
into fishponds, pollution and expansion of tourism
a. SILTATION. Excessive siltations due to deforestation
and mining activities have been observed to cause the death of
b. OVERFISHING. Overfishing means the continuous
exploitation of particular fishing ground over sometime period.
c. DESTRUCTIVE FISHING.
Practice which plague the marine ecosystem include;
-Blast fishing means the use of dynamite or any other
explosive in fishing.
-Cyanide is the common poison used by illegal fisherman.
Caused several of skin disease.
-Electro-fishing is fishing with the used of electric
-Trawl fishing is done with a net in the shape of ling conical
bag tapering from the wide-open mouth to a narrow bag at the end.
d. POLLUTION. Industrial waste.
-The instability and death of organisms associated with
corals which could ultimately lead to the extinction of species.
-Decreased productivity followed by the decreased of fish
production which results to the loss of a source of livelihood of
fisherman and other people involved in the fishing industry.
-An increase in coastal erosion.
-The DE growth of the tourism industry.
-A loss in part of our natural heritage.
e. TOURISM INDUSTRY. Lack of guidelines on marine
-Is a natural phenomenon brought about by the bloom or
predominance of floating microscopic organisms known as
-It is called red tide because of the reddish color of
dinoflagellates give to the cell when present in high cell densities.
-It organisms that caused deaths in the country has been
identified as PYRODINIUM HABAMENSE VAR COMPRESA. This
organism is attracted to sunlight during daytime and settles at the
bottom in the dark hours.
- The poison in the organism is known as SAXITOXIN. It is
water-soluble salt that affects the nervous system.
THREE CONDITIONS THAT TRIGGER RED TIDES
1. Stirring up of the sediment in the nearshore waters by wind action.
2. High temperature of water due to summer sun which makes the sea
3. Nutrient enrichment of the sea. Occurs during May and June.
PROTECTION OF MARINE ECOSYSTEM
RULES AND REGULATIONS (Implemented by the DENR)
1. Prohibit various forms of illegal fishing.
2. Prohibit the exportation of Bangus fry.
3. Prohibit the operation of commercial trawls and purse seines in certain
4. Establish fish refuges and sanctuaries.
5. Establish “closed seasons”.
6. Explore, exploit, utilize and conserve coral reef.
7. Insure continuous supply of fish in communal water areas.
8.Under take and arrange special technical assistance and training
9. Conduct research and study fish and fishery products and resources.