G2 Ecosystems and Biomes powerpoint

8/11/2019 G2 Ecosystems and Biomes powerpoint

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OPTION G: ECOLOGY & CONSERVATION

G2: Ecosystems & Biomes


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G2: Ecosystems & Biomes

G.2.1 Define gross production, net production and biomass.

G.2.2 Calculate values for gross production and net production using the equation: gross

productionrespiration = net production.

G.2.3 Discuss the difficulties of classifying organisms into trophic levels.

G.2.4 Explain the small biomass and low numbers of organisms in higher trophic levels.

G.2.5 Construct a pyramid of energy, given appropriate information.

G.2.6 Distinguish betweenprimary and secondary succession, using an example of each.

G.2.7 Outline the changes in species diversity and production during primary succession.

G.2.8 Explain the effects of living organisms on the abiotic environment, with reference to the

changes occurring during primary succession.

G.2.9 Distinguish between biome and biosphere.

G.2.10 Explain how rainfall and temperature affect the distribution of biomes.

G.2.11 Outline the characteristics of six major biomes.


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Energy

There are rarely more than

six links in a food chain;

there are usually 3-4.

This is because much of the

energy is lost at each trophic

level due to heat loss.

From 5.1


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Trophic Levels

Some energy is

incorporated

into the

organism ateach trophic

level

This energy will

not be available

for the next

trophic level.

From 5.1


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Ecosystem Energy FlowsG.2.1 Define gross production, net production and biomass.


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Ecosystem Energy FlowsG.2.2 Calculate values for gross production and net production using the equation: gross production respiration = net production.

The unit of energy used is Kjm-2y-1(energy per square meter per year)


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Ecosystem Energy FlowsENERGY

7 000 000

TROPIC LEVEL

PRODUCERS

PRIMARY CONSUMERS

SECONDARY CONSUMERS

SUN

+1 700 000

87 400


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Pyramids of Energy

Usually only 10% of plant

energy transferred.

Only 20 to 30 % of herbivoreenergy transferred to

carnivores.

Eventually all energy is lost

from system.

From 5.1


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Pyramids of EnergyG.2.4 Explain the small biomass and low numbers of organisms in higher trophic levels.


The unit of energy used is Kjm-2y-1


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Produce a pyramid of energy using this information


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What is the efficiency of the conversion of solar energy by photosynthesis?


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Calculate energy lost by plant respiration.


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Trophic Levels

BRAINSTORM

Why do you think it would be difficult to classify

organisms as belonging only to one trophic level?

G.2.3 Discuss the difficulties of classifying organisms into trophic levels.


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Primary vs. Secondary SuccessionG.2.6 Distinguish between primary and secondary succession, using an example of each.

Primary Succession Secondary Succession

The emergence of an entirely new

ecosystem, such as a volcanic island or a

sand dune.

The replacement of one ecosystem by

another following environmental change,

such as following a bush fire.

WATCH! http://geoclio.org/ensci/imagesbook/04_03_succession.swf
http://geoclio.org/ensci/imagesbook/04_03_succession.swf


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Primary SuccessionG.2.7 Outline the changes in species diversity and production during primary succession.

Primary succession is the emergence of a new

community from a new ecosystem.

Gross Production Increases

First colonisers are lichens on rock surfacesSoil builds up, following the death of smaller lichens

Larger plants take root as soil deepens

Productivity plateaus as soils carrying capacity is reached.

Species Diversity IncreasesMore soil allows for burrowers, worms and detritivores

More plats take root and provide new niches

More death lead to more soil nutrient and nutrient recycling

ONLINE TUTORIAL!

http://bcs.whfreeman.com/thelifewire/content/chp55/55020.html
http://bcs.whfreeman.com/thelifewire/content/chp55/55020.html


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Primary SuccessionG.2.7 Outline the changes in species diversity and production during primary succession.

Primary succession is the emergence of a new

community from a new ecosystem.


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Primary Succession

During succession, living organisms change the abiotic environment.

G.2.8 Explain the effects of living organisms on the abiotic environment, with reference to the changes occurring during primary succession.

SoilProduces by detritivores

(worms) following death ofother plants or animals.

Detritivores and bacteria fix

nitrogen and other inorganic

nutrients into the soil. Decay

accumulates minerals around

roots, The soil is aerated byburrowing animals which

enables more respiration and

drainage.

Plant RootsPlant roots bind the soil,preventing erosion, root

systems are supportive. Root

systems uptake, filter and

recycle massive amounts of

water, preventing flood anddrought.

Microclimatesare generatedsmall niches of differing temperature,

light levels and humidity. These new niches provide opportunities formore species, in turn affecting the abiotic environment.


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Biome vs. Biosphere

The biosphereis made up of all the worlds biomes.

All ecosystems are interdependent and events in one ecosystem

affect those in another.

G.2.9 Distinguish between biome and biosphere.


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Biomes

Biomes are climaticallyand geographicallydefined

areas of ecologically similar characteristics.


Temperature and rainfall are key abiotic features of each biome and plant and animal species

are adapted to survive in the available niches.

Climographs (temperature vs.

precipitation) show how closely related

neighbouring biomes are in terms of

their climate characteristics.


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Biomes

TundraTree-less plains and alpineregions

Low annual temperatures (mostly below

freezing) and low precipitation.

Plant species are adapted to highexposure and harsh conditions and

photosynthesise in low light and include,

short shrubs ad bushes, tough grasses,

mosses and lichens.



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Biomes

Shrubland

Warm-hot summers and cool

winters.

Dry summers and wet winters

Natural fires common in the

summerAustralia, California,

parts of the Mediterranean

Vegetation is adapted to dry

conditions (xerophytes) and some

seeds are stimulated to germinate

by fire.

Seasonal change in foliage is rare

green all year round



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Biomes

Grassland

Large annual range in temperature and precipitation

Warm-hot summers and cold winters.

Heavy rain in summer-autumn

High diversity of grasses and shrubs and some trees.

Grazing animals present



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Biomes

Temperate Deciduous Forest

Clear seasonal changes with warm summers, cold

winters and rainfall all year round.

Deciduous foliage in leaf during spring and summer and

leaves fall off in the autumn and winter.

Broadleaf trees (oaks, maples, beeches), shrubs,

perennial herbs and mosses.



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Biomes

Tropical Rainforest

High annual temperatures with little

fluctuation.

High annual rainfall with wet and dry

seasons.

High diversity of plant and animal life due to

high number of ecological niches available.

Tall trees, mosses and other plants.

Rainforests are divided into vertical layers:

forest floor, lower canopy, upper canopy andemergent top trees.



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Biomes

Desert

Hot and dry all year round, with cold nights

Very low precipitation

Plant specie are extreme xerophytes and plantand animal diversity are low. Cacti, short bushes,

some short grasses


G2 Ecosystems and Biomes powerpoint

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