Transcript Human Impact

Human Impact and the
Environment
Chapter 22
Earth’s Layers
• Geosphere
• Hydrosphere
• Atmosphere
•
Biosphere
Biodiversity
• Species diversity
– Species richness
– Species evenness
How do you study
these factors?
Are they equally
important?
• Genetic diversity
– Affects a
populations ability
to adapt when
faced with
environmental
change.
Benefits of Biodiversity
• Why is your quality of life impacted
by the extinction of species?
Environmental Issues
• Pollution
– Smog
• Nitrogen oxides, sulfur oxides, organics,
ozone
– Ozone thinning
• CFC’s deplete ozone
• Could lead to new cases of skin cancer
– Global warming
• A complex issue.
Ozone Layer
• What is it?
• Why is it
important?
• What factors
seems to
affect the
ozone layer?
• Acid Precipitation
• Land and Water Pollution
– Biological magnification
• Everyone’s problem
Bald Eagles and Lead
Poisoning--Biomagnification
Ecosystem Disruption
• Extinction
Passenger
Pigeon
Tasmanian
Tiger
Quagga
Ecosystem imbalances
• Some species are critical to the
functioning of ecosystems.
• These species are called keystone
species.
–
–
Ever built the arch at the Science Center?
Can the arch stand without the keystone?
– Keystone species
• Prairie Dogs have long been vilified by
ranchers and others who believe that they
damage the range and take valuable forage
away from cattle and other livestock. In fact,
prairie dogs are what is known as a
keystone species, a species whose very
presence contributes to the diversity of life
and whose extinction would result in the
extinction of species dependent on it.
The grazing and burrowing activities of
prairie dogs improve forage quality,
conserve water and improve soil
Human Resource Use
• Human’s use 55% of the primary
production of the Earth
• Ecological footprint: human impact
on ecosystems
• Sustainability: the ability to meet
human needs in such a way that a
human population can survive
indefinitely. (what is the Earth’s
Carrying Capacity?)
Environmental Solutions
• Conservation
Biology: identify,
protect and
manage areas that
still have
biodiversity.
• Restoration
Biology: repair
damaged
ecosystems (have
you seen the “Prairie
Restoration” signs on
the highway?)
• Species and Habitats
– Bioindicators: species that are very
sensitive to environmental change.
Ex. Amphibians,
Whooping Crane
• In 1935 only about 15 individuals left.
• 2011 census indicates around 600
individuals.
• Is this a conservation success story?
Protecting Ecosystems
Biodiversity Hotspots
Regions richest in
biodiversity but in need of
protection.
• Governments and Laws: protect
endangered species, set aside land
to protect habitats, clean up pollution,
regulate destructive activities such as
mining.
• Ecotourism: a way for developing
countries to protect their biodiversity.
Urban Ecology.
• What can you do?
• What do you do?