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Flashcards in Biogeography Deck (17)
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Describe a basic cycle which includes autotrophs and heterotrophs

Sunlight gives energy to plant
Plant takes in CO2 and gives out O2
Plants are eaten by fish/plants die
Fish are eaten by bears
Animals die
Dead animals and plants are decomposed by microbes
CO2 returns to the environment


What are the 4 essential inputs of an ecosystem?



Give the definition of metabolism and two examples

Converting inputs to outputs
Eg. Photosynthesis - solar energy to glucose
Respiration - burns glucose to make energy


Compare photosynthesis and respiration

- stores energy as sugar
- uses CO2 and H2O
- increases weight
- produces oxygen

- releases energy from sugar
- releases CO2 and H2O
- decreases weight
- consumes oxygen


Name and define the 6 types of distribution

Cosmopolitan - species or taxonomic group that is distributed widely throughout the world
Primary endemic - s or t group in a particular region native only to that region
Secondary endemic - s or t group in a particular region whose distribution has contracted so that it is now native only to the region in which it's found
Rare - restricted geographically or is widespread but never found anywhere in abundance
Disjunct - occupies areas that are widely separated and scattered
Indigenous or native - originates in a particular place or has arrived there independently of human activity


What factors control patterns of species distribution?

Climate - heavily influenced by light and moisture availability
Geological factors - tectonic movement ie. Wallace's line
Ecological factors - habitat conditions


What are the controlling physical factors in an environment?

Moisture availability
Zonal factors - regional macroclimate (Equatorial, monsoonal)
Atonal factors - no zonal organisation or structure


Where is Wallace's line?

Between Borneo and Sulawesi
Between Bali and Lombok


Who came up with the theory of continental drift?



What is vicariance and dispersal?

Vicariance - species range is divided even though the species has remained in place. May happen through tectonic action, geologic action (rise of mountain, change in course of river) or other processes
- eg species B evolves from species A after plate tectonic split and isolation
Dispersal - species range changes because of some or all individuals moving to a new location (possibly crossing a barrier)
- eg species C migrates to another island and evolves into species E on the new location


Name some biomes

Steppe grasslands
Temperate deciduous forests
Temperate grasslands
Tropical forests
Savanna region
Hot deserts


Define the biome - tundra

A vegetation of mosses, grasses and low shrubs developed in Arctic and alpine regions
Cold mean temp of warmest month


Describe the biome - taiga

Northern 'boreal' coniferous forest (Alaska, Canada, northern Scandinavia, Siberia)
Dominated by spruce
Characterised by severe and relatively dry winters


Define the biome - steppe grasslands

Areas of permanent grassland
Winters relatively cold, though the steppes may be hot in summer, precipitation less than 50cm a year
Precipitation-evapotranspiration too low to support continuous forest


Define the biomes - prairie grasslands and Savannah

Prairie grasslands are warmer than the steppes but still have a low precipitation-evapotranspiration ratio
Savannah - open grassland with scattered trees, coldest month averaging over 18 degrees Celsius


Define he biome - temperate deciduous forest

Exists where winters are milder than those areas occupied by coniferous forest and where the climate is oceanic (relatively high precipitation-evapotranspiration ratio)
Once occupied much of Europe including British Isles south of the highlands, eastern n.america and Eastern Asia
Much has been cleared and surviving fragments of ancient woodland are highly managed


What is an ecosystem?

Organisms and co-existing geologic and climactic components that interact
Ecosystems that occupy specific climactic or geographic realms are called biomes