A school level presentation on Marine ecosystems and its parts

1. MARINE ECOSYSTEM

2. THE ‘WHAT’ PART…
• Oceans cover approximately 70% of the earth’s surface with an average
depth of 2.4 miles, or 3,800 meters.
• The marine ecosystem, in addition to the temperate and tropical oceans,
includes the shorelines, with mud flats, rocky and sandy shores, tidepools,
barrier islands, estuaries, salt marshes, and mangrove forests making up
the shoreline segment.
• Conventionally, the ocean has been divided into four major ocean basins:
Atlantic, Pacific, Indian and Arctic oceans. Specific marine ecosystems such
as coral reefs, estuaries, salt mashes, mangrove forests are found
throughout the world, but are characteristic of certain areas, depending on
climate, geography, water temperature, and other physical factors

4. AQUATIC ECOSYSTEM
• An aquatic ecosystem is an ecosystem in a body of water
• The two main types of aquatic ecosystems are marine ecosystems
and freshwater ecosystems.
• Marine ecosystems are distinguished from freshwater ecosystems by
the presence of dissolved compounds, especially salts, in the water.
Approximately 85% of the dissolved materials in seawater are sodium
and chlorine. They generate 32% of the world's net primary
production.
• Freshwater ecosystems cover 0.78% of the Earth's surface and inhabit
0.009% of its total water. Freshwater ecosystems contain 41% of the
world's known fish species.

6. THE SALT MARSH
• A salt marsh is a coastal ecosystem in the upper coastal intertidal zone between
land and open salt water or brackish water that is regularly flooded by the tides.
• It is dominated by dense stands of salt-tolerant plants such as herbs, grasses,
or low shrubs.
• These plants are terrestrial in origin and are essential to the stability of the salt
marsh in trapping and binding sediments. Salt marshes play a large role in the
aquatic food web and the delivery of nutrients to coastal waters.
• Plant species diversity is relatively low, since the flora must be tolerant of salt,
complete or partial submersion, and anoxic mud substrate. The most common
salt marsh plants are glassworts
• They serve as depositories for a large amount of organic matter and are full of
decomposition, which feeds a broad food chain of organisms from bacteria to
mammals.

8. THE INTERTIDAL ZONE
• The intertidal zone, also known as the foreshore and seashore and
sometimes referred to as the littoral zone, is the area that is above
water at low tide and under water at high tide
• This area can include many different types of habitats, with many
types of animals, such as starfish, sea urchins, and numerous species
of coral.
• The well-known area also includes steep rocky cliffs, sandy beaches,
or wetlands
• The area can be a narrow strip, as in Pacific islands that have only a
narrow tidal range, or can include many meters of shoreline where
shallow beach slopes interact with high tidal excursion.

10. MAN, IT HAS GOT THE GROOVE!
• A mangrove is a shrub or small tree that grows in coastal saline or
brackish water
• The term is also used for tropical coastal vegetation consisting of
such species. Mangroves occur worldwide in the tropics and
subtropics, mainly between latitudes 25° N and 25° S.The total
mangrove forest area of the world in 2000 was 137,800 square
kilometres (53,200 sq mi), spanning 118 countries and territories.
• Mangroves are salt tolerant trees, also called halophytes, and are
adapted to life in harsh coastal conditions. They contain a complex
salt filtration system and complex root system to cope with salt water
immersion and wave action. They are adapted to the low oxygen
(anoxic) conditions of waterlogged mud.

12. THE DEEEEEEEP SEA!
• The deep sea or deep layer is the lowest layer in the ocean, existing below the
thermocline and above the seabed, at a depth of 1000 fathoms (1800 m) or
more.
• Little or no light penetrates this part of the ocean, and most of the organisms
that live there rely for subsistence on falling organic matter produced in the
photic zone.
• For this reason, scientists once assumed that life would be sparse in the deep
ocean, but virtually every probe has revealed that, on the contrary, life is
abundant in the deep ocean.
• Organisms in the deep sea are almost entirely reliant upon sinking living and
dead organic matter which falls at approximately 100 meters per day. In
addition, only about 1-3% of the production from the surface reaches the sea
bed mostly in the form of marine snow.
• The plants also do chemosynthesis.

15. THE CORAL REEF
• Coral reefs are diverse underwater ecosystems held together by
calcium carbonate structures secreted by corals.
• Coral reefs are built by colonies of tiny animals found in marine water
that contain few nutrients.
• Most coral reefs are built from stony corals, which in turn consist of
polyps that cluster in groups.
• The polyps belong to a group of animals known as Cnidaria, which
also includes sea anemones and jellyfish.

17. THE SERENE LAGOONS
• A lagoon is a shallow body of water separated from a larger body of
water by barrier islands or reefs.
• Lagoons are commonly divided into coastal lagoons and atoll
lagoons. They have also been identified as occurring on mixed-sand
and gravel coastlines.
• Lagoons are common coastal features around many parts of the
world.
• Coastal lagoons are usually connected to the open ocean by inlets
between barrier islands. The number and size of the inlets,
precipitation, evaporation, and inflow of fresh water all affect the
nature of the lagoon.

18. THANK YOU