Biomes Specific Divisions of Biosphere. Ecosystems So almost every corner of this planet, from the highest to the lowest, the warmest to the coldest,

Biomes

Specific Divisions of Biosphere

Ecosystems• So almost every corner of this planet, from the

highest to the lowest, the warmest to the coldest, above water and below, has acquired its population of interdependant plants and animals. It is the nature of these adaptations that has enabled living organisms to spread so widely through our varied planet.– David Attenborough

Biome Definition

• Large, distinct, terrestrial ecosystem characterized by particular climate, soil, plants and animals.

• Boundaries determined mostly by climate

• Precipitation next limiting factor

• Altitude next

Tundra• Cold north!!! Why not south?

• Long, harsh winters; dark 20 hrs/day

• Very short summers

• Due to tilt of earth, sunshine is “watery” and weak

• However, days are long; light 20 hrs/day

• Sun might not even set for a few days in midsummer!!!!

• Cold limits precipitation; very little available

• Tundra soils young. Why?– Only since last ice age

• Consequences?– Poor organic load– Poor nutrients

• Permafrost– Never thaws– Only a few feet down– Limits roots; no plants over a foot tall!!!– In summer when upper layer melts; water sits there– “Boggy”

• Low species diversity– Plant

• “Lots of a little”

• Monotonous landscape

– Animal• Small herbivores

– Rodents, hares

• Low species diversity– Plant

• “Lots of a little”

• Monotonous landscape

– Animal• Small herbivores

– Rodents, hares

• Larger herbivores– moose, caribou, musk-oxen

www.smouse.force9.co.uk/index.htm (moosecall)

Notice the monotonous plant life

Caribou

• Low species diversity– Plant

• “Lots of a little”

• Monotonous landscape

– Animal• Small herbivores

– Rodents, hares

• Larger herbivores– moose, caribou, musk-oxen

• Carnivores– Weasels, owls, hawks

• No reptiles!!!!!

• No amphibians!!!!

• Lots of insects

• parkscanada.pch.gc.ca/parks/nwtw/nahanni/

• tqjunior.thinkquest.org/3500/animals.htm

Taiga: Evergreen Forests of North

• Large stretches of North America and Europe• ~11% of earth’s surface!!• Again not found in Southern Hemisphere• Winters long and cold, but not as severe as

tundra• Little precipitation (rain; there is lots of

snow)

• Consequently poor soils

• Lots of ponds and lakes, depressions left from previous ice ages

• Layer of decomposed conifer detritus

• Predominant vegetation; conifers - the cone bearers

• Consequently poor soils

• Lots of ponds and lakes, depressions left from previous ice ages

• Consequently poor soils

• Lots of ponds and lakes, depressions left from previous ice ages

• Layer of decomposed conifer detritus

• Predominant vegetation; conifers - the cone bearers

• Animals = all sorts of consumers– Migrators; bear, moose, wolves, etc

Grizzly

Brown Bear

Black Bear

Wolves

Foxes

• Consequently poor soils• Lots of ponds and lakes, depressions left from

previous ice ages • Layer of decomposed conifer detritus• Predominant vegetation; conifers - the cone

bearers• Animals = all sorts of consumers

– Migrators; bear, moose, wolves, etc– Most mammals small; rodents, rabbits, fur covered

predators (lynx, mink, etc)– Birds seasonal

• Lots of insects (due to standing water)

• Some reptiles; but low species diversity

• Not good for agriculture; but huge in forestry

• 1 in 6 Canadians works in forestry

• www.taiga.org/photo/image.php3?pic=1047