Morgan Tsui
Science Olympiad
What is a biome?
A large community of plants and animals that occupies a distinct (unique characteristics) region. Biomes are
typically defined by their climate and dominant vegetation.
The aquatic biome can be broken down into two basic regions, freshwater (ponds and rivers) and marine
(oceans and estuaries).
Properties of marine and freshwater biomes
Marine regions cover about three-fourths of the Earth's surface and include oceans, coral reefs, and estuaries.
The largest biome in the world is all water. The marine biome includes all bodies of water that are salty, such
as oceans. There are 7 major oceans in the marine biome, along with smaller bodies, known as gulfs and
bays. The ocean is divided into 3 layers. The top layer is called the euphotic layer, and it is shallow enough for
light to reach it. The disphotic zone lets enough light through for it to look light twilight. The final zone, the
apotic zone, is so deep, that no light can reach it.
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salt concentration of ~ 3%
cover ~ 75% of the earth’s surface
have enormous impact on planet’s climate
evaporation of seawater provides most rainfall
ocean temperatures affect wind patterns, distribution of energy to land via currents
supply substantial portion of world’s oxygen
photosynthesis by marine algae & photosynthetic bacteria
consume huge amounts of atmospheric carbon dioxide
communities are distributed through several zones
based on
o depth of water
o degree of light penetration ( absorb )
o distance from shore
http://mason.gmu.edu/~klargen/111lectecosystemsaquaticbiomesspring04.htm
The freshwater biome is a low-saline, or sweetwater, aquatic biome that covers one fifth of the earth's
surface. Streams, rivers, swamps, bogs, ponds, lakes, ditches, puddles, and canals comprise the freshwater
biome.
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salt concentration of <1%
characteristics are influenced by
o patterns and speed of water flow
o climate of area in which its located
two categories Standing and Moving
standing (lentic) bodies of water (lakes, ponds, inland wetlands)
moving (lotic)bodies of water (rivers and streams)
Producers
Producers are organisms that can make all of their own food in an ecosystem. The
main producers of a freshwater biome are the plants and algae. When energy enters
the ecosystem as sunlight, plants and algae capture the sunlight and store it as food
energy. Through the process of photosynthesis, they provide oxygen and food for
animals. Algae are one of the most important producers of food for living organisms.
http://www.waterboards.ca.gov/water_issues//programs/outreach/waterlessons/pdf/6part6.pdf
Producers in marine biomes are most often plants, because they are the main source of energy, because they
use photosynthesis to use the sun's energy. The producer in a marine biome would often be algae, kelp, sea
weed and sea grass
The producers in fresh water are water algae, lilies and duck weed.
http://wiki.answers.com/Q/What_are_the_producers_in_a_marine_biome#ixzz1j6pcAham
Consumers
The consumers of Marine life is krill, Mollusks and Fish and zooplankton
http://www.slideshare.net/mageejeremy/marine-biomes-presentation
Consumers of an ecosystem cannot make their own food. They depend on
producers for their food and energy.
The consumers of a freshwater biome include snails, insects,
crustaceans, amphibians, fish, and aquatic birds.
Decomposers
Decomposers of an ecosystem are microorganisms, like bacteria and fungus, which are
responsible for breaking down plant and animal waste and turning it into food for other plants and
animals. Decomposers provide an important role in the maintenance of a freshwater biome.
http://www.waterboards.ca.gov/water_issues//programs/outreach/waterlessons/pdf/6part6.pdf
Marine Biome Climate
The marine biome climate has a very strong influence on the climate. The evaporation of the water from the
oceans and seas helps in formation of rain. The ocean is constantly moving and the currents and waves are
warm or cold depending on the weather and marine biome temperature in a particular region of the earth. The
marine biome temperature is just above freezing point at the north and south poles and deep in the abyssal zone.
The tropical waters have a warm marine biome climate because they are near the equator.
http://www.buzzle.com/articles/marine-biome-facts.html
Marine biome food web
All animals require food and water to survive. All aquatic plants and animals are members of the marine food
web. The first level of the marine biome food chain is covered by the phytoplankton. The next marine biome
food chain is covered by zoo planktons that eat phytoplankton. The zoo plankton are in turn eaten by the next in
line of the marine food chain, that is, krill, fishes, crustaceans, etc. The fourth level of marine food chain are
consumed by big fishes, penguins, seals, walrus and whales. The penguins and seals are eaten by polar bears
and seals hunted by human. Humans are always placed high up in the marine biome food chain as although they
are not part of the marine biome, they consume sea foods like fishes, crabs, lobsters, etc. If even one member of
the marine biome food chain becomes extinct, the food chain will go for a toss.