Transcript The Body in Motion

Biology, Seventh Edition
Solomon • Berg • Martin
Chapter 55
Humans in the
Environment
Copyright © 2005 Brooks/Cole — Thomson Learning
Biology, Seventh Edition
CHAPTER 55 Humans in the Environment
• Biological diversity
• Variety of organism considered at
three levels
–Genetic diversity
–Species diversity
–Ecosystem diversity
• Decreasing worldwide
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Biology, Seventh Edition
CHAPTER 55 Humans in the Environment
• Extinct species
• All members of the species are
dead
• Endangered species
• In imminent danger of extinction
• Threatened species
• Population is quite small, but
extinction is less imminent
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Biology, Seventh Edition
CHAPTER 55 Humans in the Environment
An extinct
species
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Biology, Seventh Edition
CHAPTER 55 Humans in the Environment
• Four causes of declining
biological diversity
• Most significantly, habitat loss and
fragmentation
• In addition, pollution, introduction of
invasive species, pest and predator
control, and commercial activity
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Biology, Seventh Edition
CHAPTER 55 Humans in the Environment
Percentage of imperiled U.S. species that
are threatened by various human activities
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Biology, Seventh Edition
CHAPTER 55 Humans in the Environment
• Conservation biology
• Study of how humans affect
organism
• Development of ways to protect
biological diversity
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Biology, Seventh Edition
CHAPTER 55 Humans in the Environment
Habitat destruction
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Biology, Seventh Edition
CHAPTER 55 Humans in the Environment
Biodiversity hotspots
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Biology, Seventh Edition
CHAPTER 55 Humans in the Environment
• In situ conservation
• Efforts to preserve biological
diversity in the wild
• Ex situ conservation
• Efforts to preserve biological
diversity in human-controlled
settings
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Biology, Seventh Edition
CHAPTER 55 Humans in the Environment
• Endangered Species Act (ESA)
• Authorizes the U.S. Fish and
Wildlife Service to protect biodiversity domestically and abroad
• CITES
• International organization to protect
species from illegal international
wildlife trade
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Biology, Seventh Edition
CHAPTER 55 Humans in the Environment
Illegal
commercial
harvesting
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Biology, Seventh Edition
CHAPTER 55 Humans in the Environment
Organisms
listed as
endangered
or
threatened
in the U.S.,
2003
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Biology, Seventh Edition
CHAPTER 55 Humans in the Environment
• Forests provide many ecosystem
services
• Watershed protection
• Soil erosion prevention
• Climate moderation
• Protection from flooding
• Wildlife habitat
• Greatest problem is deforestation
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Biology, Seventh Edition
CHAPTER 55 Humans in the Environment
Deforestation
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Biology, Seventh Edition
CHAPTER 55 Humans in the Environment
• Greenhouse gases
•
•
•
•
•
Carbon dioxide
Methane
Surface ozone
Nitrous oxide
Chlorofluorocarbons
• Causes greenhouse effect and global
warming and enhanced greenhouse
effect
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Biology, Seventh Edition
CHAPTER 55 Humans in the Environment
Mean annual global temperature,1960 to 2002
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Biology, Seventh Edition
CHAPTER 55 Humans in the Environment
• Surface Ozone
• Ozone (O3) is a form of oxygen
• Human-made pollutant in lower
atmosphere
• Occurs naturally in the stratosphere
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Biology, Seventh Edition
CHAPTER 55 Humans in the Environment
• Ozone destruction in the
stratosphere
• Amount of ozone in the stratosphere
is declining (ozone depletion)
• Large areas of ozone thinning over
Antarctica and the Arctic
• Excessive exposure to UV radiation
linked to human disease, i.e., skin
cancer
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Biology, Seventh Edition
CHAPTER 55 Humans in the Environment
Increase in greenhouse gases, preindustrial to
present
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Biology, Seventh Edition
CHAPTER 55 Humans in the Environment
Enhanced
greenhouse
effect
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Biology, Seventh Edition
CHAPTER 55 Humans in the Environment
UV radiation and the ozone layer
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Biology, Seventh Edition
CHAPTER 55 Humans in the Environment
Ozone thinning
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