Grassland: Ecosystem in Australia

Content 1 : Biome Description
Grassland:
Ecosystem in Australia
What are
grasslands?
The distribution of Grassland Biome
Grassland is mainly a vegetation domination, where it covers
more than 40 percent of the Earth’s land surface. It is
geographically widespread than any other group of plants and
could be found in possibly every single continent except
Antarctica. About 35 percent of the continent receives so little
rain, it is effectively desert. Organisms such as birds, mice, and
ground squirrels live on or below the ground feeding on the
vegetation. It is also a place of changing colors, in winter, the
grasslands are white; the grasslands turn green in spring; in the
summer days, the plants wilt and turns into yellow or brown.
Ultimately, the climate determines the growing season for plants,
including grassland biomes. [1]
In general, grasslands occupy the interior of continents, where rainfall is limited
because of the far distance from ocean. They are also found in areas that are
too dry for most trees to survive and also places where it is not as shaded. Crops
and plants situated in shady areas will not be able to go through photosynthesis
due to the limited source of energy available.
Climatogram
Grasslands are divided into two types on Earth: temperature grasslands and
tropical savanna grassland.
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Temperature grasslands occupy regions with a temperature climate and is most
found in North America, eastern Europe, Turkey, northern Iran, central Asia, and
part of southern China. On the other hand, Savanna grassland are mainly found
in Africa, south America, and Australia. The weather will always be warm Savanna
grasslands, since occasionally the regions will cause precipitation, leading to
more frequent rainfalls. Eventually, there will be abundance of grasses, which
results in a biome of grassland. [1]
This climatogram shows the precipitation and temperature rates for grassland
regions in Australia. In general, the temperature is fairly warm throughout the
entire year while precipitation is fairly high.
abiotic factor
influences on the
structure of
Grassland biome
Australia used to be a land of rivers, lakes, and forests.
However, its climate turned drier about 10 million years
ago. Eventually the lakes disappeared as forests shrank
because trees needed plentiful supply of water.
However, grasses remained sustainable because it can
manage with less source of water. Consequentially, the
retreat of forest was accompanied by the expansion of
grassland. [1]
Content 2 : BioSphere of the ecosystem
[2]
Food web
The relationship among plants and animals are shown in the diagram above, where the
arrows illustrates the source linking to the sink for all matter and energy flows. The plants
uses photosynthesis to make carbohydrates out of carbon dioxide and water. This food
is later eaten by animals, and since plants produce it they are identified as producers.
Herbivore then become primary consumers because they eat plant food directly.
Carnivores feed on primary consumers such as Dingo so they are secondary consumers,
which are also the top predators in this food web. In this scenario, the rabbit is
considered as one of the keystone species because it is the largest influence in this
food web that causes the existence of Dingo and Wedge-Tailed Eagle which are the
secondary consumers. Dingo is the largest terrestrial predator in Australia, which serves
as the apex species in this food web. Eventually, when organisms die, bacterias can
help break down any organic matters in the ecosystem. [1]
*90% loss per trophic level on average*
Content 3: :Tropic Structure
Pyramid of Numbers
[4]
Secondary
consumers: Dingo
and Wedge-Tailed
Eagle
354,000
organisms/km^2
Primary consumers: goat, brown hare,
rabbit, red kangaroo 708,000
organisms/km^2
Producers: Green grass, blackberries, wild grasses, weeds
5,842,000 organisms/km^2
Pyramid of Biomass
Secondary
consumers: Dingo
and Wedge-Tailed
Eagle (1610g/km^2)
Primary consumers: goat, brown hare,
rabbit, red kangaroo 2495g/km^2
Producers: Green grass, blackberries, wild grasses, weeds
3,204,032 g/km^2
I found this information on the internet, which
provides me the approximate number of
individuals in each trophic level to satisfy the
ecosystem of grassland in Australia. This
assumption is based off a production of 6
million plants in grassland ecosystem, in which if
calculated, the primary consumers only obtain
10 percent of the energy producers releases
because organisms uses energy for respiration,
movement, and reproducing more offsprings.
*5,842,000 divided by 708,000 = 0.12 = 12
(approximately) [4,5]
I found this information on the internet, which
provides me the approximate biomass in each
trophic level to satisfy the ecosystem of
grassland in Australia. This assumption is based
off a production of 6 million plants in
grassland ecosystem, in which if calculated,
the primary consumers only obtain 10 percent
of the energy producers releases because
organisms uses energy for respiration,
movement, and reproducing more offsprings.
Content 4: :Carbon cycle
Carbon cycle
[2]
In a grassland ecosystem, the carbon cycle specifically focuses on the
photosynthesis process, where autotrophs absorb carbon dioxide from the
atmosphere and convert it into carbohydrates, lipids and all the other carbon
compounds that they require. By doing so, it allows a reduction in the carbon
dioxide concentration of the atmosphere. With the combination of carbon
dioxide, gas, and sunlight in the atmosphere, it produces plants in grasslands
regions, which are producers and source of food obtained by primary
consumers. As seen in the diagram, plants would eventually be fed by
heterotrophic organisms, and herbivores will be fed by carnivores. This food
web is a cycle that continues until the plants wilt or animals die from conditions
such as the inability to undergo the ecology of “survival of the fittest”. Dead
bodies or wilted plants will get decomposed by bacteria, algae, and much
more that would later be fragmented and soak into the soil. Fossilization then
takes place to create fossil fuels that are later released to the atmosphere
again. [3]
Meanwhile, humans begin to use fossil fuels for industrial purposes
and for factory goods. In relationship to how human activities have
affected our society, factories and other burning activities have
released an abundance of carbon into the atmosphere, which
creates an unbalanced and interfered the natural process of
carbon cycle. This influence causes a high concentration of carbon
dioxide in the atmosphere that is redundant for our carbon cycle. [3]
Content 5: Evolution and Adaptation
[8] Weeds
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These two organisms, weeds and dingos were selected in a grassland type
ecosystem due to several factors. First of all, grasslands occur in deep interior of
continents that are far from the ocean. Since the climate of grasslands are too dry
fairly warm, and rainfall is generally low, the carbon cycle allows carbon dioxide to
emerge with gas and sunlight to produce weeds, which are the autotrophs and
producers of the ecosystem. As more grass type plants dominate the entire region,
adaptation factors starts to form in the environment, selecting a community of
organisms.
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However, due to the unevenly distributed rainfall in grasslands throughout the year,
grasses have varying productivity rates. Perhaps primary consumers vary in eating
long grass or short grass, therefore when rainfall is particularly low during a season,
one of the extreme phenotypes in primary consumers may be selected. This is an
example of directional selection, which causes a shift in the population. As a result,
the secondary consumer would also vary. Nonetheless, Dingos are one of the
examples.
Another way
Dingos are
selected is
through the
process of domestication. Dingos are wild dogs that live on
Australian grasslands. However, it has been discovered that
present day dingos are descended from a pair of
domesticated dogs that entered Australia from Indonesia
about 5,000 years ago.
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Organism can either be evolved naturally or
domesticated through cultivating and taming
them. [7]
[9] Dingo
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Sources:
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[1] Strelecky, Richard Garratt, et al. Biomes of the Earth: Grasslands. New York: An imprint of Infobase Publishing, 2006. Print.!
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[2] http://aanikacollingwoodscience7.weebly.com/food-web.html!
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[3] http://www.biologydiscussion.com/essay/food-chain-in-ecosystem-explained-with-diagrams/1669!
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[4] http://www.globalchange.umich.edu/globalchange1/current/lectures/kling/energyflow/highertrophic/trophic2.html!
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[5] http://www.biomass.net/Biomass-and-Trophic-Levels.html!
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[6] http://signgehki.xoom.it/prevx-cs33/loforv.html!
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[7] http://encyclopedia2.thefreedictionary.com/Grassland+ecosystem!
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[8] http://nwfarmsandfood.com/wp-content/uploads/2010/06/weeds.jpg!
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[9] http://upload.wikimedia.org/wikipedia/commons/5/5a/Dingo_face444.jpg!
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