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

(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