Transcript The World's Biomes

Module 4:
Biomes of the World
(Part-I)
Biomes are the the world's major communities,
classified according to the predominant
vegetation and characterized by adaptations
of organisms to that particular environment
(Campbell )
Biome is a large geographical region whose
climate produces a characteristic climax
association of plants and animals
Major Biomes of the World
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Desert
Grassland
Forest
Tundra
Aquatic
– Freshwater
– Marine
Distribution of major biomes of the world
Key points to understand a biome
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Climate
Distribution and geography
Special adaptations of vegetation
Types of animals found and their
adaptations
Desert Biome: Distribution
Desert Biome
•Covers one fifth of the land surface
•Rainfall is less than 50 cm per year
•Specialized vegetation and animals
•Soils have abundant nutrients, but
little or no organic matter
•Disturbances are fairly common
1.
2.
3.
4.
Hot and Dry Deserts
Semi-arid Deserts
Coastal Deserts
Cold Deserts
Hot and Dry Deserts: Distribution
• North America: Chihuahua, Sonoran, Mojave
and Great Basin; Southern Asia: Thar; Africa:
Sahara, and Australia
Hot and Dry Deserts
• Climate is warm throughout the year and very hot during
summers
• Evaporation rates exceeds rainfall
• Soils are course-textured, shallow, rocky or gravely with
good drainage; no subsurface water
• Flora:
Cactus, ocotillo, turpentine bush, prickly pears, false
mesquite, sotol, ephedras, agaves and brittlebush
• Fauna:
Small nocturnal carnivores, insects, reptiles, birds
Sonoran desert
http://mwsu-bio101.ning.com/forum/topics/a-sonoran-desertcommunity
Hot and Dry Deserts: Animals
Thorny devil
Moloch horridus
http://biology.ucr.edu/people/faculty/Garland.html
Hot and Dry Deserts: Animals
Kangaroo-rat
Dipodomys spectabilis
Semi arid Deserts
• Montana and Great Basin; North America,
Newfoundland, Greenland, Russia, Europe and
northern Asia.
• Summers are moderately long and dry
• Soil ranges from sandy to fine textured
Semi arid Deserts
• Flora:
Creosote bush, bur sage (Franseria deltoidea),
Acacia constricta, cat claw cactus, Prosopis
spp., brittle bushes (Encelia farinosa), Zizyphus
spp.
• Fauna:
Rabbits; insects like grasshoppers and ants;
lizards and snakes; burrowing owls and the
California thrasher
Semi arid Deserts
Coastal deserts
• Occur in moderately cool to warm areas
• Soil is fine-textured with a moderate salt
content; fairly porous with good drainage
Coastal Desert
•Flora:
salt bush, buckwheat bush, black bush,
rice grass, little leaf horsebrush, black sage,
and Euphorbia spp.
•Fauna:
spoonbill, sandpiper, coyote and badger,
toads, great horned owl, golden eagle and
the bald eagle, lizards and snakes
Coastal Desert: Fauna
spoonbill
Fennec fox
Dorcas gazelle
Cold Deserts
• Cold winters with snowfall less than 10
inches; short, moist and moderately warm
summers
• Soil is heavy, silty and salty
Cold Deserts
• Flora:
Bunchgrass, Artemisia spp.(sagebrush),
Chrysothamnus spp. (rabbit bush)
• Fauna:
Proghorn antelope, bighorn sheep, marco
polo sheep, mountain lion
Marco polo
sheep
Proghorn
antelope
Basin wildrye
Grassland Biome: Distribution
•Large terrains of grasses, herbs and grasses
•Average annual precipitation is enough to support grasses;
erratic..drought and fires prevent growing of trees
•Soil is thin and dry
Steppes
• Dry, cold grassland
• Found in USA, Mongolia, Siberia, Tibet and
China
• Found between forest and desert biome
• Grasses dominate
Steppes
Steppes: vegetation
Rhubarb
Rheum rhabarbarum
Tumble weed
Fringed sagebrush
Salsola collina
Artimisia frigida
Steppes : Fauna
Saiga antelope
Northern Lynx
Saiga tatarica
Felis lynx
Prairies: Distribution
• Found in North America
• Dominated by herbaceous plants and
grasses
Prairies: Vegetation
Indian grass
Sorghastrum nutans
Milkweed
Turkey feet grass
Andropogon gerardii
Asclepias currasavica
Prairies: Fauna
American bald eagle
Haliaeetus leucophalus
Prairie dog
Cynomis ludovicianus
Pampas: Distribution
• Found in South America
• Flat, fertile plains; warm, humid climate
• Frequent fires
Pampas: vegetation
Silver pampas grass
Geofrroy’s cat
Cortaderia selloana
Oncifelis geoffroyi
Ombu
Phytolacca dioica
Savanna
• Also known as tropical grasslands
• Warm temperature year around with a
very long dry winter,and a lots of rain in
the summer
savanna
Savanna: Flora and Fauna
•Flora:
•Cynodon dactylon, Pennesetum perpureum (napier
grass/ elephant grass), Eucalyptus cinerea, Acacia
tortilis, Acacia senegal
•Fauna:
•Elephant, buffaloes, antelopes, rhino, Giraffe, Wild
Dog, Black Mamba, Caracal, Chacma Baboon,
Egyptian Mongoose, Emu, Grant's Zebra, Koala Bear,
Lion, leopard, cheetah, Nigriceps Ants, Nile Crocodile
Savanna: vegetation
Euphorbia ingens
Acacia tortilis
Savanna: Fauna
Emu
Black mamba
Egyptian mongoose
savanna baboons
Forest Biome
1.
2.
3.
4.
Tropical forests
Deciduous forests
Alpine forests
Boreal forests OR Taiga
Tropical forest: Distribution
Tropical Forest Biome
• Occur near the equator
• Cover around 6% of the earth’s surface
• Distinct seasonality: winter is absent, and only two
seasons are present (rainy and dry).
• Temperature and water are not limiting
• Soil is nutrient-poor and acidic. Decomposition is
rapid and soils are subject to heavy leaching
• Greatest diversity of species
Tropical Forest Biome
• Canopy is multilayered and continuous, allowing
little light penetration
• Vegetation:
mostly evergreen, with large dark green leaves.
Plants such as orchids, bromeliads, vines (lianas),
ferns, mosses, and palms are present
• Fauna:
numerous birds, bats, small mammals, and insects
Tropical forest: vegetation
Bambusa tulda
Ceiba pentandra
Ficus spp.
Tropical forest: Fauna
spider
Golden toad
Temperate deciduous Forest Biome
• Occur in eastern North America, northeastern
Asia, and western and central Europe
• Well-defined seasons with a distinct winter
• Moderate climate and a growing season of
140-200 days during 4-6 frost-free months
Temperate deciduous Forest Biome
• Temperature varies from 30° C to 30° C
• Precipitation (75-150 cm)
is distributed evenly
throughout the year
• Soil is fertile, enriched with
decaying litter
Temperate deciduous Forest Biome
• Flora:
Broad leaved deciduous plants-oak,
hickory, pine, beech, hemlock, maple,
basswood, cottonwood, elm, willow,
and spring-flowering herbs
• Fauna:
squirrels, rabbits,
skunks, birds, deer,
mountain lion, bobcat,
timber wolf, fox, and
black bear.
Alpine Forests: Distribution
• Himalayan mountains
• Andes mountains…South America
• Rocky mountains…western North America
Alpine: Climate
• Found in the high mountains all over the world
usually above 10,000 ft.
• Cold and dry throughout the year
• Soil is well drained
• Vegetation:
Alpine Phaceli, Bear Grass, Bristle cone Pine, Moss
Campion, Polylepis Forest, Pygmy Bitterroot, Wild
Potato
• Fauna:
mountain goat, snow leopard, Yak, Himalayan
tahr, takin, marmot etc.
Himalayan Alpine: Distribution and climate
• Dry air, low precipitation
• Harsh environment with long cold winters,
mild short summers
Himalayan Alpine: Vegetation
Rhododendron spp.
Himalayan Alpine: Fauna
Snow leopard
Panthera uncia
Himalayan tahr
Hemitragus spp.
Yak
Bos grunniens
Himalayan Alpine: Fauna
Takin
Budorcas
taxicolor
Marmot
Marmota
himalayana
Taiga biome: Distribution
Boreal forests/ Taiga biome
• Largest terrestrial biome, covers 11% area
• Broad belt of Eurasia and North America: two-thirds
in Siberia with the rest in Scandinavia, Alaska, and
Canada
• short, moist, and moderately warm summers and
long, cold, and dry winters
• The length of the growing season is 130 days
• Precipitation is primarily in the form of snow, 40100 cm annually.
Boreal forests/ taiga
• Soil is thin, nutrient-poor, and acidic
• Canopy permits low light penetration, and as a result, under
story is limited.
• Flora :Evergreen conifers with needle-like leaves: Balsam Fir,
Black Spruce, Douglas-fir, Eastern Red Cedar, Jack Pine,
Paper Birch, Siberian Spruce, White Fir, White Poplar, White
Spruce
• Fauna: American Black Bear, Bald Eagle, Bobcat, Canadian
Lynx, Gray Wolf, Grizzly Bear, Long-Eared Owl, Red Fox, River
Otter, Snowshoe Rabbit, Wolverine
Taiga Biome: vegetation
Balsam fir Abies balsamea
Jack pine Pinus banksiana
Taiga Biome: vegetation
White Birch Betula populifolia
White popular Populus alba
Taiga Biome: vegetation
Douglas fir Pseudotsuga
menziesii
White spruce Picea glauca
Taiga Biome: Fauna
American Black bear
Ursus americanus
Snow shoe rabbit
Bald eagle
Haliaeetus
leucocephalus
Lepus americanus
Tundra biome: Distribution
•Tundra Finnish word ‘tunturia’ barren land
•Bleak and treeless place
•World’s youngest, coldest and driest biome..formed 10,000
years ago
•Covers 20% of the Earth’s surface..Northern hemisphere
Tundra biome: Climate
•The ground is permanently frozen 10 inches to
3 feet
•Main seasons: Winter..summer
•Average annual temperature -280C [ max –
700C; max 120C]
•Land of midnight sun
•Strong winds; 6-10 inches of precipitation each
year
•One of the major sinks of carbon
Tundra biome: Lichens
Bear berry
Tundra biome: vegetation
•Adaptations: low
growing plant; fine
silky hair, leathery
leaves
Arctic willow
Salix arctica
Arctic moss
Calliergon giganteum
Arctostaphylos uva-ursi
Tundra biome:
animals
Arctic fox
Lagopus alopex
Caribou / Reindeer
Rangifer tarandus
References
• Campbell, N.A. 1996. Biology, 4th
Edition. The Benjamin/Cummings
Publishing Company, Inc., Menlo Park,
California.
• http://www.ucmp.berkeley.edu/exhibits/
biomes/marine.php
• http://earthobservatory.nasa.gov/Experi
ments/Biome/Images/pictemperate.jpg