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BiomesA Biome is a terrestrial

ecosystem occupying an extensive geographical area

and is characterized by a particular plant community.

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video on biomes

http://www.youtube.com/watch?v=WuejxJttBqo&safe=active

Biomes:

Physical factors that can effect the location of biomes include:• Temperature• Rainfall• Altitude and Latitude• Mountain Chains• Air currents• Ocean currents

The land surface of the Earth is divided into a number of geographic areas distinguished by particular types of dominant vegetation.

These categories of plant life are called biomes.

Often biomes are thought of as climatic regions

E.g. grassland, savanna, temperate forest, desert, boreal forest, tropical rain forest, tundra

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Temperature and Rainfall:Terrestrial Biomes are greatly influenced by rainfall and temperature.

Temperature influences the availability of water to plants, soil & animals.

• The hotter it is the faster water evaporates

• Cold temperatures can lock the water up in ice

Latitude:Latitude measured in degrees, is the distance north or south from the equator, which is at 0 ° latitude.

Latitude affects the angle at which the sun strikes the Earth’s surface. This is due to the tilt of the Earth’s Axis

.

Mountains have an important impact on climate.thinning air retaining less heat

As elevation increases temperature decreases due to

The temperature drops 2o C (3.5o F) for every 305 meters (1000 feet) Mountains also create a local dry area called a rain shadow on the leeward side

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In general the world can be divided into biomes based on latitude.

The Major Terrestrial Biomes

http://dsc.discovery.com/videos/assignment­discovery­shorts­iii­biomes­tundra.html

Video : Tundra

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The TundraLocation:

South of the ice caps

of the Arctic extending

across North America

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Low average temperature.

Average yearly precipitation of 10­12 cm. Due to low evaporation, the region is wet with ponds and bogs during the short, warm summer (poor drainage).

The bogs consisting of peat soaked within melt water form because melting snow cannot drain into the permafrost.

The Tundra Climate

Growing season of 2 months, harsh cold winters.

> Mosses

> Lichens (reindeer moss)

> Grasses

> Sedges

> Shrubs.

The word tundra means“marshy plain”.

The Tundra Plants

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• Insects include black flies and mosquitoes.

The Tundra AnimalsLargest animals: Caribou, musk oxen, reindeer.

Top predators: include wolves, grizzly bears, white fox and snowy owl.

Herbivores: Arctic hares, grouse and lemmings (shrew type animal).

Summer sees migrations of birds to feed on large groups of insects.

Permafrost (permanently frozen soil) is present.

The thin, uppermost layer of the soil (active layer) will thaw during summer but is of poor quality because the cold reduces activity of decomposers (bacteria and fungi) so there is slow cycling of matter and little organic matter, thus slow decomposition.

The Tundra Soil

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• http://dsc.discovery.com/videos/assignment­discovery­shorts­iii­biomes­taiga.html

Video : Boreal

Boreal Location:

South of the tundra extending across North America.

Newfoundland is considered part of the boreal forest biome.

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• Cold winters with the ground covered in snow and warm summers causing the ground to thaw completely.

• Average precipitation of 50­100 cm.

• Growing season is about 120 days.

Boreal Climate

• Conifers (pine, fir, spruce)

• Deciduous conifers (tamarack)

• Some deciduous trees (birch, maple)

• Blueberry & cranberry shrubs

• Ferns

• Moss, etc.

Boreal Plants

Evergreen trees, small compact, wax coated leaves.

Can’t compete with deciduous trees in temperate zones.

The Pacific coast forests have adapted to dry summers and can store water and nutrients due to massive size. Thick bark protects from fires.

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• Moose

• Bears and grizzly

• Marten (Pine martin)

• Lynx

• Snowshoe hares

• Foxes, wolf

• Beavers

• elk

• deer

• Variety of birds such as warblers (coniferous nesters)and grouse.

Wide variety of insects, including pests of trees like the sawflies and Spruce budworms

Boreal animals

The is acidic due to decaying conifer needles

A deep litter layer and higher temperatures allow more rapid decomposition.

Mineral deficient are due to large amounts of water moving through the soil

Boreal Soil

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http://dsc.discovery.com/videos/assignment­discovery­shorts­iii­biomes­temperate­forest.html

Video : temperate

Location:

South of the boreal forest in eastern and central Canada.

Temperate Deciduous Forest

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Temperate Deciduous Climate • Cold winters with hot summers.

• Average precipitation of 75 to 150 cm.

• Growing season is about 180 days.

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Temperate Deciduous Plants• Deciduous trees (maple, birch, chestnut, beech) that lose their leaves seasonally. Further south trees are oak and hickory.

• Well developed and diversified shrubs, ferns, moss, etc.

It has 4 layers of plant growth which include the tree layer, shrub layer, field layer and ground layer.

• White­tailed deer­ feed on shrubs and seedlings

• Black bear

• Gray fox, wolves, mountain lions feed on other mammals

• Skunk

• Squirrels, Chipmunks, Racoons, opossums, Mice feed on nuts, fruits and insects.

• Wide variety of birds including wild turkeys and woodpeckers.

• Amphibians, reptiles and insects are also abundant and diverse.

Temperate Deciduous Animals

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• Brown forest soils.

• Thin surface litter (decomposing leaves) layer due to rapid decomposition, earthworms being active.

• Upper soil is mildly acidic due to the litter layer. Acidity decreases with depth.

• More fertile than Taiga soils because of high levels of nitrates and other soil nutrients held by clays.

A Rich top soil due to large population of decomposers.

Temperate Deciduous Soil

http://www.greatpacificmedia.com/#terrestrial_biomes_dvd

Video : Grassland

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Grassland

• Very cold winters with hot summers.

• Average precipitation of 25 to 75 cm.

• Growing season is about 180 days.

Grassland Climate

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Grassland Plants • Mainly Grasses mixed with legumes and some

annuals.

• Wild flowers

• Trees are limited to low valleys and low mountains.

Grassland Animals • Snakes

• Badgers, prairie dogs, ground squirrel (burrowers)

• Bison were once numerous.

• Antelope, elk, coyote, wolves.

• Grassland birds are limited due to the vegetation, such as sparrows, seed eatibg rodent, hawks.

• Most abundant insect is the grasshopper.

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Grassland Soil • Soil is deep and rich (fertile) causing this biome to become the most productive farmland on Earth.

• Called chernozem soils, or black earths, organic matter accumulates in the upper portion of the soil, making it dark.

• Neutral or slightly alkaline soil.

Temperate (Mediterranean) Shrub lands or chaparral:Coastal regions bordering deserts

Low rainfall like a desert, but fog and longer rainy season

Mild moist winters, long, dry summers: Mediterranean climateVegetation:

Dense stands of shrubs and small trees with waxy or fuzzy evergreen leaves to conserve water.

Can withstand frequent fires.

Animals:

Mule deer, lizards, rabbits, rodents are often small and dull colored to match environment.

California is considered to have a Mediterranean scrub biome.

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November 03, 2017Deserts:Subtropics , low levels of rainfall(10 ­20 inches). Less than 25 cm of rainfall a year.

Nights are cold

Brief growing seasons

Vegetation:

Succulents (eg sedum) adapted to store water. Perennials with large shallow root systems to quickly soak up desert storms.

Coating of plant is water proof . Water stored in thick stems of succulents.

Specialized annual wild flowers that flower after storms for only a month or less.

Animals:

Reptiles, insects are common. Snakes, lizards, owls, kangaroo rat.

Many animals are small and are active at night to hunt for food.

Tropical Rain Forests: Humid equatorial regions, uniform temperature, lots of rain.

Seasonal rainfall

Tropical rain forests get 200­400 cm of rainfall per year.

Complex ecosystem, has more plant and animal species than all the other biomes put together.

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Animals:

Birds, monkeys, and insects. Edible material near ground is scarce so many are are living in or among trees.

Vegetation:

Huge broad leaf evergreen trees dominant this biome.

Competition among plants for light is strong

Upper canopy of solitary tall trees, can be 50­60m tall, (150 ft).

Lower story canopy is continuous at 30 ­40 m (90 ­120 ft).

Many vines and epiphytes (plants grow above ground) growing on the trees.

Few plants on forest floor, little leaf litter.

Soil is infertile,low in nutrients, mostly red clay.

Aquatic Biomes

Video: aquatic biome

http://dsc.discovery.com/videos/assignment­discovery­shorts­iii­biomes­aquatic.html

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The Oceans

­But oceans are only about 1/3 as productive as land.

­Oceans cover 71% of the Earth’s surface

• Made up of a salt water environment.

The most important factors in marine ecosystems are sunlight and nutrients

But although water appears to be transparent it blocks light energy. Light can only go about 200m.

Most of the nutrients are concentrated near the bottom!Along the continental shelves life is much denser than in the open ocean because nutrients are washed out from the land.

The Oceans

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Most nutrients are concentrated near the bottom sediments where light is too low for photosynthesis.

Upwelling

transports

these sediments

to the surface

photic zone

Supports photosynthesis

aphotic zone

Supports chemosynthesis only

Ocean Life Zones

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The life in the oceans is divided into two main groups:

Benthic (bottom dwelling). Pelagic (free floating)

.

The start of the food chain in oceans is the free floating phytoplankton (autotroph).Consisting of algae, protists, shrimp and other crustaceans.

They are the basis of the food web for most pelagic organisms

Next in the food chain

are the free floating Zooplankton

(heterotroph)

There are two types of plankton:

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Coastal wetlands are rich in nutrients, water is shallow and plants can attach to the bottom.

Breeding grounds for a range of organisms including most commercially important fish species.

Estuaries

video http://www.youtube.com/watch?v=tU2F36Y3AdU&list=UU1nf2pzxQRKrFUfrUAwp4oA&safe=active

http://www.youtube.com/watch?v=1lLtfbde16A&list=UU1nf2pzxQRKrFUfrUAwp4oA&index=14&safe=active

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Video: freshwater biome

http://www.youtube.com/watch?v=tU2F36Y3AdU&feature=related

Freshwater Aquatic Biomes

• Made up of any of body of water that is made of freshwater such as lakes, ponds, streams, and rivers.

• They cover roughly 20% of the Earth.

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Two types of Lakes 1) Oligotrophic ­ deep, clear very cold and very low nutrients

2) Eutrophic ­ shallow, warm,not clear, excellent supply of nutrients

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Freshwater BiomesComposed of three zones:

Littoral Zone­ splashing area where sunlight reach bottom of the lake, lots of light, warm/cold, oxygen; close to shore; and organisms include waterlillies and sedges

­Limnetic Zone­open area of the lake with sufficient light and oxygen; heat will decrease with depth; and organisms include plankton and fish

­Profundal Zone­ deep part of lake with no sunlight, very little oxygen; cold water; and organisms include bacteria and bottom dwelling invertebrates

Profundal

A Lake

Limnetic

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