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BIOMES
Biomes are very large regions of Earth, whose distribution depends
on the amount of rainfall and the temperature .
Each biome is characterized by specific plants(flora) and specific
animals(fauna).
Biome Types:
Aquatic Biomes:
Terrestrial Biomes:
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Aquatic Biomes:
Marine (largest biome on earth)
Estuary
Fresh Water
Terrestrial Biomes:
Tundra
Taiga (largest terrestrial biome) _
Temperate Deciduous Forest
Shrubs
Grassland
Desert
Tropical rainforest
Aquatic Biomes
Marine biome
The largest biomes, covering 70% of Earth’s surface. Most stable
biomes, with temperature that varies little because water has high heat
capacity. Provide most of Earths food and oxygen because of algae and
plankton.
Subdivided to:
Intertidal Zone: Where land and water meet.
Neritic Zone: Coral reefs are found, supporting variety of organisms.
Oceanic Zone:
1)pelagic zone : include Photic zone & aphotic zone
2)benthic (ocean bottom) zones.
3)abyssal zone: deepest part of ocean.
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Fresh water biome
Include: lakes, rivers, streams, ponds, wetlands. Low salt conc.
a) Photic zone:
1) Littoral Zone: Near the shore of lake. Many plants grow here and
support a wide variety of consumers. Like insects, snails, amphibians.
2) Limnetic Zone: Far from shore and extends downward as far as
light penetrate. Many photosynthetic organisms live here.
B) Aphotic zone (Profundal Zone): Too deep zone.
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Estuary water biome
Zone where fresh water meets salty water.
Characterized by high nutrients and plenty of fish.
Terrestrial Biome
Tundra:
There are two types of tundra:
1)Alpine tundra: on top of high mountains.
2)Arctic tundra: near poles.
Called permafrost or permanently frozen topsoil. (Deep root growth is
difficult because roots cannot penetrate the frozen ground.)
Very few trees.
Plants: grasses, mosses. (Small plants).
Animals: Arctic wolves, Arctic foxes, Arctic hares, reindeer, and
polar bears.
The number of individual organisms in the tundra is high but the
number of species is small
Called frozen desert
No water
Dry
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Taiga (Coniferous Forest)
largest terrestrial biome.
Dominated by conifers (evergreen trees) like cedar, pine, red wall.
Principal large mammals include moose, black bear • Has greater variety
in animal species than does the tundra.
Have very cold winters
Temperate Deciduous Forest:
Trees drop or shed their leaves in winter, and leaves regrow in spring.
Rich soil .
Animals: squirrels, raccoons, black bears.
plants: more plant species than does the taiga -birch, oak, maple tree.
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Shrub land:
characterized by shrubs (short, branched tree), and frequent fires.
Grasslands:
Low annual rainfall .
Low-growing plants and few scattered trees like oaks.
It supplies largest amount of food for human.
Two types:
1- Temperate grasslands(prairies): Farmland because of their fertile soil.
_ Animals: wild horses, bison.
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2- Tropical grasslands(savanna): support some of largest herbivores:
zebras, giraffes, elephants, rhinoceros.
Desert:
Characterized by dryness. Extreme temperature fluctuations
Plants: adapted for drought-resistant, Cacti can expand to hold extra
water and have modified leaves called spines, which protects against
attacking a cactus for its water .
Characteristic animals include rodents, kangaroo rats, snakes, lizards,
arachnids, insects, and few birds
Nocturnal activity: most animals are active at night, and burrow
underground or hide in shade during daytime.
Tropical Rain Forest:
Has the greatest plant and animal species diversity.
Highest rainfalls.
High temperature.
Highest humidity among terrestrial biomes.
Very tall trees with interlacing tops that form a dense canopy, keeping
the floor of forest dimly lit even at midday.
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Many trees are covered with epiphytes.
Poor soil, most nutrients stored in plants.
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