• What is a biome?
– A group of ecosystems that have the same climate and dominant communities
– A large geographical area with distinctive plant and animal groups, which are adapted to that particular environment
• The climate • The soil • The communities that inhabit it
• Many organisms are adapted to the conditions of the biome
• They have tolerance – Ability to survive and reproduce under conditions
that differ from their optimal conditions
• Tropical rain forest
• Tropical dry forest
• Tropical savanna
• Desert
• Temperate grassland
• Temperate woodland and shrubland
• Temperate forest
• Northwestern coniferous forest
• Boreal forest
• Tundra
Abiotic Factors • High temperatures & humidity • Heavy rainfall • Thin, nutrient-poor soils
Geographic Distribution • Parts of:
• South and Central America
• Southeast Asia • Parts of Africa • Southern India • Northeast
Australia • Almost always
near the equator
Dominant Plants • Broad-leaved evergreen trees • Ferns • Large woody vines and
climbing plants • Orchids and bromeliads
Dominant Wildlife • Herbivores such as sloths,
tapirs, and capybaras • Predators such as jaguars • Anteaters • Monkeys • Birds such as toucans,
parrots, and parakeets • Insects such as butterflies,
ants, and beetles • Piranhas and other
freshwater fishers • Reptiles such as caymans, boa
constrictors, and anacondas
Interesting Info: • Rainforests now cover less than
6% of the Earth’s land surface. • More than half of all the world’s
plant and animal species live in tropical rainforests.
• Tropical rainforests produce 40% of the Earth’s oxygen.
• Rainforests have more types of trees than any other area of the world.
• 25% of all medicines we use come from rainforest plants.
• More than 1,400 varieties of tropical plants are thought to be potential cures for cancer.
Abiotic Factors Generally warm year-round Alternating wet and dry seasons Rich soils subject to erosion
Geographic Distribution Parts of:
Africa South and Central America Mexico India Australia Tropical islands
Dominant Plants Tall, deciduous trees that form a dense canopy during the wet season Drought-tolerant orchids and bromeliads Aloes and other succulents
Dominant Wildlife Tigers Monkeys Herbivores such as elephants, Indian rhinoceroses, & hog deer Birds such as great pied hornbills, pied harriers, and spot-billed pelicans Insects such as termites; reptiles such as snakes and monitor lizards
Abiotic Factors Warm temperatures Seasonal rainfall Compact soil Frequent fires set by
lightning
Geographic Distribution Large parts of:
Eastern Africa Southern Brazil Northern Australia
Dominant Plants Tall, perennial grasses Sometimes drought-tolerant and
fire-resistant trees or shrubs
Dominant Animals Predators such as lions,
leopards, cheetahs, hyenas, and jackals
Aardvarks Herbivores such as elephants,
giraffes, antelopes, and zebras Baboons Birds such as eagles, ostriches,
weaver birds, and storks Insects such as termites
Abiotic Factors o DRY!!! Low precipitation o Temperature may be
warm or cold o Soils rich in minerals, but
poor in organic material
Geographic Distribution o Africa o Asia o Middle East o United States o Mexico o South America o Australia
Where is the world’s largest
desert?
Antarctica!!! It’s bigger than
the Sahara.
Dominant Plants o Cacti and other succulents o Creosote bush and other plants
with short growth cycles
Dominant Wildlife o Predators such as mountain
lions, gray foxes and bobcats o Herbivores such as mule deer, pronghorn antelopes,
desert bighorn sheep, and kangaroo rats o Bats o Birds such as owls, hawks, and roadrunners o Insects such as ants, beetles, butterflies, flies, and
wasps o Reptiles such as tortoises, rattlesnakes, and lizards
Abiotic Factors Warm to hot summers Cold winters Moderates, seasonal
precipitation Fertile soils Occasional fires
Geographic distribution Central Asia North America Australia Central Europe Upland plateaus of South
America
Dominant Plants Lush, perennial grasses and herbs Most are resistant to drought, fire, and cold
Dominant Wildlife Predators such as coyotes and badgers—
historically included wolves and grizzly bears
Herbivores such as mule deer, pronghorn antelopes, rabbits, prairie dogs, and introduced cattle—historically included bison
Birds such as hawks, owls, bobwhites, prairie chickens, mountain plovers
Insects such as ants and grasshoppers Reptiles such as snakes
Abiotic Factors • Hot, dry summers • Cool, moist winters • Thin nutrient-poor soils • Periodic fires
Geographic Distribution • Western coasts of North
and South America • Areas around the
Mediterranean Sea • South Africa • Australia
Dominant Plants • Woody evergreen shrubs
with small leathery leaves • Fragrant, oily herbs that grow
during winter and die in summer
Dominant Wildlife • Predators such as coyotes, foxes,
bobcats, and mountain lions • Herbivores such as blacktailed deer,
rabbits, and squirrels • Birds such as hawks, California quails,
warblers, and other songbirds • Reptiles such as lizards and snakes • Butterflies
Abiotic Factors • Cold to moderate winters • Warm summers • Year-round precipitation • Fertile soils
Geographic Distribution • Eastern United States • Southeastern Canada • Most of Europe • Parts of Japan,
China, and Australia
Dominant Plants • Broadleaf deciduous trees • Some conifers • Flowering shrubs • Herbs • A ground layer of
mosses and ferns
Dominant Wildlife • Deer • Black bears • Bobcats • Turkeys • Numerous songbirds • Nut and acorn feeders such as squirrels • Omnivores such as raccoons and skunks
Abiotic Factors o Mild temperatures o Abundant precipitation
during fall, winter, and spring o Relatively cool, dry summer o Rocky, acidic soils
Geographic Distribution o Pacific coast of northwestern
United States and Canada, from northern California to Alaska
Dominant Plants o Douglas fir o Sitka spruce o Western hemlock o Redwood
Dominant Wildlife o Bears o Large herbivores such as
elk and deer o Beavers o Predators such as owls,
bobcats, and members of the weasel family
Abiotic Factors Long, cold winters Short, mild summers Moderate precipitation High humidity Acidic, nutrient-poor soil Earth’s largest terrestrial
biome
Geographic distribution Northern Europe North America Asia
Dominant Plants Needle-leaf coniferous trees
such as spruce and fir Some broadleaf deciduous trees Small, berry-bearing shrubs
Dominant Wildlife Predators such as lynxes and
timber wolves and members of the weasel family
Small herbivorous mammals Moose and other large
herbivores Beavers Songbirds and migratory birds
Abiotic Factors Strong winds Low precipitation Short and soggy summers Long, cold, and dark winters Poorly developed soild Permafrost
Geographic Distribution Northern North America Asia Europe
Dominant Plants Ground-hugging
plants such as mosses, lichens, sedges, and short grasses
Dominant Wildlife A few resident birds
and mammals that can withstand the harsh conditions
Migratory waterfowl, shore birds, musk ox, Arctic foxes, and caribou
Lemmings and other small rodents
Mountain Ranges • Found on all
continents • Conditions depend
on elevation • Precipitation rises
and temperature falls with increasing elevation
• Dominant plants and animals get smaller and hardier as the elevation increases
Polar Ice Caps • Very cold year-round • Few plants and algae—producers
are primarily lichens and mosses • North Pole:
• Dominant wildlife include polar bears, seals, and insects.
• Arctic Ocean is covered with sea ice, and ice caps cover most of Greenland
• South Pole: • Dominant wildlife includes
penguins and marine mammals including the leopard seal and a variety of large whales.
• Antarctica is covered by ice that may be up to 5 kilometers thick.
Flowing-Water Ecosystems (Rivers & Streams)
o Unidirectional flowing water
o Flowing-water ecosystems are extremely variable, depending on location and conditions.
Standing-Water Ecosystems (Lakes & Ponds)
Standing or still water
Richness depends on supply of nutrients, temperature, & sunlight
Some are seasonal, but others remain year-round
Often have limited species diversity due to isolation
Water Zones: Littoral Zone
Topmost zone near the shore
Submerged areas shallow enough to allow rooted plants to grow
Water Zones: Limnetic Zone
Near the surface Open water; further
from shore Dominated by phyto-
and zooplankton
Water Zones: Profundal Zone
Deep water Light does not
penetrate (no autotrophes)
Much colder and denser than at surface
Abiotic Factors • Water either covers the soil or is
present at or near the surface of the soil for at least part of the year
• May be flowing or standing • May be freshwater, salty, or brackish
(mixture of salt and freshwater) • Highest species diversity of all
ecosystems
Geographic Distribution • Widely distributed around globe—
especially at or near coastlines
Main Types of Wetlands • Bogs
• Often dominated by sphagnum moss
• Typically form in depressions where water collects
• Marshes • Often contain cattails,
rushes, and other tall, grass-like plants
• No trees or shrubs • Swamps
• Water flows slowly • Often look like flooded
forests • Presence of trees and shrubs
distinguishes it from a marsh
Dominant Plants • Submerged water
plants such as seagrasses and eelgrass
• Floating water plants such as water lilies and duckweed
• Emergent waterplants (roots are completely submerged) such as cattails and arrow arum
• Surrounding trees and shrubs such as silver maple, cypress, and mangrove
Dominant Wildlife • Fish – many fish depend on
wetlands as hatcheries and nursery grounds
• Amphibians – aquatic and terrestrial frogs
• Reptiles – alligators & crocodiles, snakes, lizards, turtles
• Mammals – large herbivore and predators such as the Florida panther
• Monotremes (in Australia) – platypuses
• Insects and invertebrates – shrimp & shellfish
Estuaries Areas where freshwater
empties into oceans, forming “brackish” water
Interesting diversity of life—some adapted specifically to brackish water
Often shallow
Mangrove Swamps Dominant plants are several
species of salt-tolerant trees, collectively called mangroves
Widespread across tropical regions, such as Florida and Hawaii
Example: Everglades National Park in Florida
Salt Marshes Temperate-zone estuaries
dominated by salt-tolerant grasses above the low-tide line and seagrasses under water
Found along much of the eastern coast of North America
Ocean Zones/Regions • Intertidal Zone:
• “Where the ocean meets the land”
• May be submerged or exposed as tides come in and out
• Very diverse & productive
Ocean Zones/Regions • Coral Reefs:
“Rainforests of the Sea” • Widely distributed in
shallow warm water • Nutritionally poor
water—nutrients are supplied primarily from algae & corals
• Extremely diverse (25% of all known marine species)
• Great Barrier Reef • Nearly 2,000 miles
long & 133,000 sq. mi.
• Over 2,900 individual reefs & 900 islands
Ocean Zones/Regions • Pelatic Zone:
• Open ocean • Usually cold water • Much less
productive
Ocean Zones/Regions • Benthic Zone:
• Ocean floor (below Pelagic Zone)
• Temperature decreases and pressure increases with depth
• Rich ecosystems, but no photo-synthesis
Ocean Zones/Regions • Abyssal Zone:
• Deepest parts of the ocean, including mid-ocean ridges
• Very cold water, extremely high pressures
• Deep ocean vent (chemosynthetic) ecosystems