biomes 4.3. biomes what is a biome? a complex of terrestrial communities that cover a large area...
TRANSCRIPT
BiomesBiomes4.34.3
BiomesBiomes
• What is a biome? • A complex of terrestrial communities that cover a large area characterized by certain soil and climate conditions and particular plants and animals.
BiomesBiomes• Can all kinds of
organisms live in every biome?
• What allows species to survive in their biome?
• No- Not all species of organisms can live in every biome.
• Species have adaptations to help them adapt to different conditions
ToleranceTolerance
• What is meant by tolerance?
• Ability to survive and reproduce under conditions that differ from their optimal conditions.
• Too much or too little of any environmental factor can make it difficult for an organism to survive.
Frozen wood frog
http://www.pbs.org/wgbh/nova/sciencenow/video/3209/i05.html
Biomes & ClimateBiomes & Climate• What are the
two main components of climate?
• What is a microclimate?
• Temperature • Precipitation
• A small area within a biome where the climate differs from the climate around– When driving to school on a
sunny day, you go through a valley blanketed by fog
The 10 Major BiomesThe 10 Major Biomes
• Tropical rain forest
• Tropical dry forest
• Tropical savanna
• Desert
• Temperate grassland
• Temperate woodland & scrubland
• Temperate forest• Northwestern
coniferous forest• Boreal forest
(Taiga)• Tundra
The Major BiomesThe Major Biomes• What can cause
variations within a biome?
• What is a transitional area?
• Microclimates • Differences in exposure • Elevation above or below sea
level• Presence of rock outcroppings
• Areas between one biome and the next where plants and animals become more or less common to the biomes adjacent one another
Tropical Rain ForestTropical Rain Forest• Canopy
– 50-80 m above the forest floor
• Understory – area below the canopy
• Abiotic – hot & wet year-
round– thin, nutrient poor
soils
• Biotic – home to more
species than all other biomes combined
• Geographic distribution– South & Central America– Southeast Asia– Parts of Africa– Southern India– NE Australia
Tropical Dry ForestTropical Dry Forest
• Rainfall is highly seasonal.
• Trees drop their leaves during dry season.
• Abiotic– warm year-round– alternating wet & dry
seasons– rich soils subject to
erosion
• Geographic Distrib.– Parts of Africa– South & Central America– Mexico– India– Australia– Tropical Islands
• Biotic– deciduous trees, drought-
tolerant plants – tigers, monkeys,
elephants, birds, snakes, monitor lizards, etc.
Tropical SavannaTropical Savanna• More seasonal
rainfall than deserts, but less than tropical dry forests
• Abiotic – warm temperatures– seasonal rainfall– compact soil– frequent lightning fires
• Geographic Dist.– Eastern Africa– Southern Brazil– Northern
Australia
• Biotic – Grasslands. – Spotted with isolated trees
and small groves– lions, cheetahs,
rhinoceroses, elephants, giraffes, baboons, eagles, ostrich, etc.
DesertDesert
• Annual precipitation is less than 25 cm. Vary based on elevation and latitude. Extreme temperature changes & extreme conditions
• Abiotic – Low precipitation
– variable temps
– soils rich in minerals but poor in organic material
• Geographic Dist.– Africa– Asia– Middle East– United States– Mexico– South America – Australia
• Biotic – Mountain lions,
bobcats, pronghorn antelope, bighorn sheep,
– owls, hawks, rattlesnakes, lizards, etc.
Temperate Temperate GrasslandsGrasslands• Rich mix of
grasses and some of the world’s most fertile soil.
• Abiotic – Warm to hot summers, cold
winters – moderate seasonal precipitation – fertile soils– occasional fires
• Geographic Dist.– Central Asia– North America– Australia– Central Europe– South America upland
plateaus
• Biotic
– Lush perennial grasses, most drought, fire, & cold resistant
– coyotes, wolves, grizzly bears
– Rabbits, prairie dogs, snakes, etc.
Temperate Woodland & Temperate Woodland & ScrublandScrubland
• Semiarid climate. Growth of dense low plants that contain flammable oils makes fires a constant threat.
• Abiotic– Hot, dry summers– Cool, moist winters– Thin, nutrient-poor
soils– Periodic fires
• Geographic Dist.– Western coast of North
& South America– Areas around the
Mediterranean Sea– South Africa– Australia
• Biotic– Woody evergreen
shrubs, oily herbs– Coyotes, fox, bobcats– Deer, rabbits, squirrels– Lizards, snakes,
butterflies, etc.
Temperate ForestTemperate Forest
• Cold winters that halt plant growth for several months. Deciduous trees shed leaves in autumn, new plant growth in spring.
• Abiotic– Cold to moderate
winters– Warm summers– Year-round precipitation– Fertile soils
• Geographic Dist.– Eastern US– SE Canada– Most of Europe– Parts of Japan– China– Australia
• Biotic– Coniferous trees &
deciduous trees, mosses, ferns
– Deer, black bear, squirrels, skunk
– Songbirds, turkeys
Northwestern Coniferous Northwestern Coniferous Forest (Temperate Rain Forest (Temperate Rain Forest)Forest)• Mild, moist air from
Pacific Ocean provides abundant rainfall.
• Abiotic– Mild temperatures– Abundant precipitation during
fall, winter, & spring– Relatively cool, dry summer– Rocky, acidic soils
• Geographic Dist.– Pacific coast of NW US– Canada– Northern California to
Alaska
• Biotic– Redwood trees, Spruce– Bears, elk, deer, owls, bobcats,
weasels, etc.Twilight Series is set here
Boreal Forest (Tiaga)Boreal Forest (Tiaga)
• Also referred to as Taiga. Bitterly cold winters, mild summers to allow ground to thaw.
• Abiotic– Long, cold winters– Short, mild summers– Moderate precipitation– High humidity– Acidic, nutrient-poor
soils
• Geographic Dist.– North America– Asia– Northern Europe
• Biotic– Needleleaf coniferous
trees, small berry-bearing shrubs
– Lynxes, timber wolves, moose, beaver, songbirds, migratory birds
TundraTundra• Characterized by
permafrost (layer of permanently frozen subsoil). Ground thaws a few centimeters in summer becoming soggy & wet.
• Abiotic– Strong winds– Low precipitation– Short, soggy summers– Long, cold, dark winters– Poorly developed soils
• Geographic Dist.– Northern North America– Asia– Europe
• Biotic– Ground hugging plants– Musk ox, arctic fox,
caribou, lemmings, small rodents, migratory waterfowl, shore birds
Other Land AreasOther Land Areas
• Some areas of land on Earth do not neatly fall into the major biome categories.
• Mountain Ranges- found on all continents. – Abiotic and biotic
conditions vary with elevation. As elevation rises, temperature decreases and precipitation increases.
Other Land Areas• Polar Ice Caps-
border the tundra, cold all year
• Northern polar regions- – Arctic Ocean covered with sea
ice & a thick ice cap over most of Greenland
• South polar regions-– Antarctica is covered by a layer
of ice nearly 5 km thick– Dominant wildlife:
• Penguins and marine mammals