Transcript BIODIVERSITY

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BIODIVERSITY
Miranda Amey & Ian Cassidy
What is Biodiversity?
 Biodiversity is the variety of life in
the world or in a particular habitat
or ecosystem.
 It is also one of the measures of
health for an ecosystem
 Biodiversity is consistently rich in
the tropics and less rich in the
polar regions
What is the crisis?
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The loss of biodiversity throughout the earth.
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This creates unstable ecosystems and makes it
difficult for communities to adapt within their
ecosystem
The extinction of species increasing every day.
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Some scientists estimate 1/5 of all species alive
today could be extinct or nearly extinct by
2020.
 The Arizona Jaguar became extinct due to an
increased demand for its fur. As the human
population increased in the areas inhabited by
the jaguar, the hunting and shooting increased
and the last of this rare animal was shot in 1905
in New Mexico
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Some is natural (due to evolution etc.) but
certain activities have unnaturally sped up this
process!
 To what extent is the degradation of biodiversity
natural, and to what extent is it the fault of
mankind?
Indicators
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Indicator species are highly sensitive to
environmental changes and their populations
increase or decrease significantly depending on
changes in the environment.
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Frog populations are very vulnerable to
pollution and other forms of change, while
sludge worms are good indicators of low
oxygen concentration in waterways.
Biotic indices are calculated via the number of
tolerant and intolerant species at a time. The
numbers of these organisms in the indicator
species populations can be monitored over
time directly so they are easy to keep track of.
 Why would aquatic creatures be more accurate
indicators than terrestrial creatures?
Causes
 Human activities
 Millions of people live in moist tropical regions.
 Deforestation
 90% of the lowland forests in Ecuador have been destroyed
and cleared.
 Habitat destruction
 Tropical forests are the most diverse, but are being
destroyed at the fastest rate.
Effects
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The effects of biodiversity impacts both forests and
people.
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Loss of particular plant species means loss of unknown
economic potential- loss of food, fibers, medicines
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Some organisms are vanishing that may be the most
useful to humans, but we’ll never know.
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Rosy periwinkle from Madagascar aids Hodgkin’s disease
Loss of just one species can ruin an entire ecosystem.
Predators have lost prey, and prey undergo severe
population changes which is devastating
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Entire ecosystem can collapse
 What are some ways mankind might reverse/halt its
effect on biodiversity?
Prevention
 The Nature Conservancy is an organization dedicated towards
conserving precious lives, and the resources they need
 Steps have been taken towards preventing a great loss of bio
diversity.
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Many areas have set up wildlife, scientific and nature reserves
that preserve diversity and recovery of threatened species
These range from big to small, government owned, public or
private
They are managed by controlling alien species and restoring
ecosystems degraded by human impact
 Logging is monitored and controlled – if some are cut down,
more are planted
Types of Conservation
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In Situ Conservation
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Places where an animal is found in its own natural habitat and
is not allowed to be disturbed by humans and their activities.
Keeps the animals out of danger zones and allows them to live
and reproduce naturally. Most animals typically survive at a
greater rate using in situ conservation, and preserving their
habitat allows other species to live, thus preserving
biodiversity.
Ex Situ Conservation
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Captive breeding, animals kept in zoos or parks are allowed to
reproduce in order to give chance to increase in number, with
the possibility of eventually reintroducing some of the
offspring into the wild. Unfortunately many do not reproduce.
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Elephants are an example.
Botanic gardens are sites where many plant species are planted
in controlled environments to maintain their species.
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The Botanic Gardens of Kew has a massive collection of 50,000
species.
Seed banks are where seeds are kept in cold and dry storage,
since they stay in good condition for hundred of years.
 What is the most effective way to prevent the loss
of biodiversity?
 http://library.thinkquest.org/17456/loss1.html