Chapter 6Chapter 6BiomesBiomes

Section 1Section 1What is a Biome?What is a Biome?

BiomeBiome

A biome is a large region characterized by a A biome is a large region characterized by a specific type of climate and certain types of specific type of climate and certain types of plants and animal communities.plants and animal communities.

Biomes and VegetationBiomes and Vegetation

Biomes described by vegetation because Biomes described by vegetation because they are the most noticeable characteristics.they are the most noticeable characteristics.– Plants determine organisms that can live there.Plants determine organisms that can live there.– Plants have adaptations to allow them to Plants have adaptations to allow them to

survive.survive. Cacti conserve and retain water.Cacti conserve and retain water.

Biomes and ClimateBiomes and Climate

Climate refers to the weather conditions, such as Climate refers to the weather conditions, such as temperature, precipitation, humidity, and winds, in an area temperature, precipitation, humidity, and winds, in an area over a long period of time.over a long period of time.

Temperature and PrecipitationTemperature and Precipitation– Biomes where rainfall is not frequent – cacti and desert shrubsBiomes where rainfall is not frequent – cacti and desert shrubs– Biomes with rainfall – large treesBiomes with rainfall – large trees

Latitude and AltitudeLatitude and Altitude– Latitude – the distance north or south of the equatorLatitude – the distance north or south of the equator– Altitude – height of an object above sea levelAltitude – height of an object above sea level– As both increase, biomes and vegetation changeAs both increase, biomes and vegetation change– Rainforests – close to equatorRainforests – close to equator

Section 2Section 2Forest BiomesForest Biomes

Tropical Rain ForestsTropical Rain Forests

Located in a belt around the Earth near the Located in a belt around the Earth near the equator.equator.

Help regulate world climate and play vital Help regulate world climate and play vital roles in the nitrogen, oxygen, and carbon roles in the nitrogen, oxygen, and carbon cycles.cycles.

Always humid and warmAlways humid and warm

Tropical Rain ForestsTropical Rain Forests

NutrientsNutrients– Most nutrients in the plants, not in the soil.Most nutrients in the plants, not in the soil.– Organic matter decays quickly in hot, wet Organic matter decays quickly in hot, wet

conditions. Plants quickly take up nutrients.conditions. Plants quickly take up nutrients.– Removed so efficiently that water running out of Removed so efficiently that water running out of

the soil may be as clear as distilled water.the soil may be as clear as distilled water.

Tropical Rain ForestsTropical Rain Forests

LayersLayers– Emergent Layer – tallest trees. Trees emerge into Emergent Layer – tallest trees. Trees emerge into

direct sunlight.direct sunlight.– Canopy – Primary layer of rain forest. Trees can grow Canopy – Primary layer of rain forest. Trees can grow

to more than 90 feet.to more than 90 feet. Lower canopy – receives less light. Lower canopy – receives less light.

– Epiphytes, organisms that grow on tall trees, live here.Epiphytes, organisms that grow on tall trees, live here.– OrchidOrchid

– Understory – very little lightUnderstory – very little light Many of our house plant are native to tropical rain forests. Many of our house plant are native to tropical rain forests.

Because they adapted to low levels of light, they are able to Because they adapted to low levels of light, they are able to grow indoors.grow indoors.

Collared AnteaterWreathed Hornbill

Costa Rican MantisOrchid

Threats to the Rain ForestsThreats to the Rain Forests

Habitat Destruction – occurs when land Habitat Destruction – occurs when land inhabited by an organism is destroyed or inhabited by an organism is destroyed or altered.altered.– Every minute – 100 acres of rain forest clearedEvery minute – 100 acres of rain forest cleared

Exotic Pet TradingExotic Pet Trading– Illegally trapping animals and selling at high Illegally trapping animals and selling at high

pricesprices– Planet in PerilPlanet in Peril

Temperate ForestsTemperate Forests

Temperate rain forests - occur in North Temperate rain forests - occur in North America, Australia, and New Zealand.America, Australia, and New Zealand.– Olympic National Park – Washington stateOlympic National Park – Washington state– Large amount of precipitation, high humidity, Large amount of precipitation, high humidity,

and moderate temperatures.and moderate temperatures.

Temperate Deciduous ForestsTemperate Deciduous Forests

Trees drop their broad, flat leaves each fall.Trees drop their broad, flat leaves each fall. Located between 30 degrees and 50 degrees Located between 30 degrees and 50 degrees

north latitudes.north latitudes. Temperature and vegetation changesTemperature and vegetation changes PlantsPlants

– Maple, Oak, small shrubs, ferns, mossesMaple, Oak, small shrubs, ferns, mosses AnimalsAnimals

– Squirrels, bears, grasshoppers, deerSquirrels, bears, grasshoppers, deer– Many birds are migratory – fly south to warmer Many birds are migratory – fly south to warmer

weather and more food.weather and more food.

TaigaTaiga

Northern coniferous forest that stretches in Northern coniferous forest that stretches in a broad band across the Northern a broad band across the Northern Hemisphere just below the Arctic CircleHemisphere just below the Arctic Circle

Plants Plants – Conifer – tree with needle-shaped leaves and Conifer – tree with needle-shaped leaves and

seeds that develop in conesseeds that develop in cones

Animals Animals – Snowshoe hares, lynx, wolvesSnowshoe hares, lynx, wolves

Section 3Section 3Grasslands, Desert, and Grasslands, Desert, and

Tundra BiomesTundra Biomes

SavannasSavannas

A tropical biome dominated by grasses, A tropical biome dominated by grasses, shrubs, and small treesshrubs, and small trees

Rain falls mainly during wet season, which Rain falls mainly during wet season, which last for only a few months of the year.last for only a few months of the year.

AnimalsAnimals– Elephants, giraffe, cheetah, lion, hyena Elephants, giraffe, cheetah, lion, hyena

Temperate GrasslandsTemperate Grasslands

Cover large areas of the interior continents, Cover large areas of the interior continents, where there is moderate rainfall, but still too where there is moderate rainfall, but still too little for trees to grow.little for trees to grow.

PlantsPlants– Grasses and wildflowers – roots form dense Grasses and wildflowers – roots form dense

layers to survive drought and firelayers to survive drought and fire AnimalsAnimals

– Pronghorn antelope, bison, prairie dogsPronghorn antelope, bison, prairie dogs Threats – farming and overgrazingThreats – farming and overgrazing

ChaparralChaparral

A temperate shrubland biome that is found in all five A temperate shrubland biome that is found in all five parts of the world with a Mediterranean climate.parts of the world with a Mediterranean climate.– Moderately dry, coastal climate, with little or no rain in Moderately dry, coastal climate, with little or no rain in

summersummer PlantsPlants

– Low-lying, evergreen shrubs and small treesLow-lying, evergreen shrubs and small trees– So well adapted to fire that they can resprout from small bits So well adapted to fire that they can resprout from small bits

of surviving plant tissue.of surviving plant tissue. AnimalsAnimals

– Quail, lizards, chipmunk, mule deer – brownish-gray to blend Quail, lizards, chipmunk, mule deer – brownish-gray to blend in with brushin with brush

ThreatsThreats– Human developmentHuman development

DesertDesert

Areas that have widely scattered vegetation Areas that have widely scattered vegetation and receive very little rain.and receive very little rain.

PlantsPlants– Succulents – cacti– thick, fleshy stems and Succulents – cacti– thick, fleshy stems and

leaves that store water. leaves that store water. Spines on cacti keep thirsty animals from devouring Spines on cacti keep thirsty animals from devouring

plantplant

AnimalsAnimals– Gila monsters, rattlesnakes Gila monsters, rattlesnakes

TundraTundra

Located in northern arctic regionsLocated in northern arctic regions Winter too cold and dry to permit growth of trees.Winter too cold and dry to permit growth of trees.

– Permafrost – deeper layers of soil that are permanently Permafrost – deeper layers of soil that are permanently frozen throughout the year.frozen throughout the year.

VegetationVegetation– Mosses and lichens – plants that grow close to the groundMosses and lichens – plants that grow close to the ground

Animals Animals – Caribou, wolves, moose, arctic foxesCaribou, wolves, moose, arctic foxes

ThreatsThreats– Oil exploration disrupts habitats of plants and animalsOil exploration disrupts habitats of plants and animals– Planet in Peril – Polar BearsPlanet in Peril – Polar Bears