Transcript Biodiversity and Conservation ppt

Chapter 5
Biodiversity and
Conservation
Biodiversity
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Variety of species in a specific area.
Richest environments for
biodiversity are warm and moist
biomes such as tropical rain forests,
coral reefs, and tropical lakes.
It increases the stability of an
ecosystem.
Biodiversity Loss and Species
Extinction
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Extinction – disappearance of a
species when the last of its members
dies
Endangered species – a species
numbers become so low that
extinction is possible
Threatened species – when a
population of species is likely to
become endangered
3 Types of biodiversity
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Genetic Diversity- the variety of genes
in an ecosystem. This increases the
chance that a species will survive.
Species Diversity- number of different
species and the abundance of each
species. It increases as you move
closer to the equator.
Ecosystem Diversity- variety of
ecosystems present in biosphere.
Importance of Biodiversity
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1. Direct economic value- humans depend
on plants and animals to provide food,
clothing, energy, medicine, and shelter.
2. Indirect economic value- a healthy
biosphere provides many services to
humans and other organisms (oxygen, safe
drinking water, etc)
3. Aesthetic and scientific values- some
things are just beautiful or interesting to
study.
Threats to Biodiversity
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Background extinction- gradual
process of species becoming extinct
Mass extinction- an event in which a
large percentage of all living species
become extinct in a relatively short
time. *The last one was 65 million
years ago.
Factors that threaten biodiversity
Today’s high rate of extinction is
different than past mass extinctions
because it is a result of a single
species- Homo sapien.
1. Overexploitation- excessive use of
species that have economic value
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2. Habitat loss – habitats that are
destroyed due to human actions or
extreme weather
 Ex. Cutting down the rain forest
leads to loss of fertile land
 Ex. Coral reefs being destroyed by
disease, temperature, pollution
3. Habitat fragmentation – separation
of wilderness areas from other
wilderness areas
 Contributes to extinction, change
in biodiversity, invasion of exotic
species, increases risk of fire
4. Habitat degradation (pollution) –
damage to a habitat by pollution; such
as air, water, and land
 Acid precipitation – rain, sleet,
snow, and fog with low pH
 Pesticides use such as DDT
poisoning animals through the
food chain
5. Introduced Species- non-native
species that are either intentionally or
unintentionally transported to a new
habitat. They are not a threat to their
native ecosystem, but when introduced
to a new one, can cause a disruption.
Conserving Biodiversity
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Human activities are destroying and
degrading the habitats for many wild species
and driving some of them to premature
extinction.
Sooner or later all species become extinct
because they cannot respond successfully
to changing environmental conditions.
Current extinction rates are 100 to 10,000
times higher than natural extinction rates
because of human activities.
What can we do?
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Limit our use of non-renewable
resources (resources that are found
on Earth in limited amounts or that are
replaced by natural processes over
long periods of time).
Establish sustainable use (using
resources at a rate at which they can
be replaced or recycled while
preserving the long-term
environmental health of the biosphere
Protecting Biodiversity
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Establish protected areas – national
parks
Identify hot spots- areas that have
high levels of endemic species
(species only found in that area) and
critical levels of habitat loss
Create corridors between habitat
fragments- safe passageways for
organisms
Restoring Ecosystems
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Bioremediation- the use of living
organisms, such as prokaryotes,
fungi, or plants, to detoxify a polluted
area
Biological augmentation- adding
natural predators to a degraded
ecosystem.