Download Life on earth

Chapter 38
Conservation
Biology
We are now living through a biodiversity crisis
A rapid decrease in Earth’s great variety of
organisms
6th mass extinction event in Earth’s history
PowerPoint Lectures for
Biology: Concepts and Connections, Fifth Edition
– Campbell, Reece, Taylor, and Simon
Lectures by Chris Romero Modified by K. McCoy
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
THE BIODIVERSITY CRISIS: AN OVERVIEW
38.1 Human activities threaten Earth’s biodiversity
• Biodiversity includes
– Genetic diversity, within and between
populations --raw material for adaptation
– Species diversity
– Ecosystem diversity
Figure 38.1B
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
• Human activities
– Threaten diversity at all levels
Figure 38.1A
Known extinct during historical times
or threatened with extinction
12% if birds
24% mammals
20% of all freshwater fish
200 species of plants in US extinct
730 endangered
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
Biodiversity is valuable for its own sake
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
Biodiversity is valuable for its own sake (movie)
Some people believe that all living
organisms have an innate right to life.
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
Biodiversity is valuable for its own sake and…
38.2 Biodiversity is vital to human welfare
– Also provides food, clothing, shelter,
oxygen, medicines, and ecosystem
services
– 25% of all prescriptions are plant based
Rosy periwinkle is native to Madagascar
8000 species of flowering plants many not
studied yet
Madagascar has lost 80% of its forests
and 50% of its native species!
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
Figure 38.2
Rosy periwinkle
treats cancer
Ecosystem diversity
•Network of interactions among populations of
different species.
•Means that extinction of one species can
negatively impact the ecosystem and connected
ecosystems…(aquatic to terrestrial)
•Each ecosystem has a global function… if
altered can affect biosphere
• “protective pastures” of phytoplankton in ocean
uses CO2 for photosynthesis (producers) and
for building shells…
– Feeding us and protecting us from global
warming…
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
Ecosystem services
•Ecosystems have economic value
• Wetland reduce severity of floods
• Natural predators reduce crop pests
• Pollination
• Plants purify air
• Decomposition of waste
• Nutrient cycling
•Value of services 1997 = 33 trillion US $
•Global gross national product 1997 = 18 trillion
GNP~ total market value goods and services produced plus the income accruing
as a result of investments.
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
So ecosystems are valuable and
necessary for maintaining our current
comfortable way of life.
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
Humans are a part of the environment
and not apart from it. Your actions
affect other organisms.
The things we eat, wear, drive, and
purchase have a direct impact on
organisms, populations, and
communities around the globe.
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
Figure 38.3A
38.3 Habitat destruction, introduced species, and
overexploitation are the major threats to
biodiversity
• Introduced species
– Can disrupt communities by competing with
or preying on native species
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
•
Figure 38.4
Habitat destruction
Chemical pesticides
May be concentrated by
biological magnification
– Phytoplankton absorb
chemicals
– Zooplankton eat a lot of
phytoplnkton
Concentration of PCBs
•
Herring
gull eggs
124 ppm
Lake trou
4.83 ppm
Smelt
1.04 ppm
– Fish eat a lot of zooplankton
– Larger fish eat a lot of small fish
– Birds and humans eat a lot of
large fish
Zooplankton
0.123 ppm
Phytoplankton
0.025 ppm
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
38.4 Pollution compounds our impact on other species
• Effects of pollution include
– Acid rain, ozone depletion, eutrophication,
and dead zones
(http://www.smm.org/deadzone/what/top.html and
http://www.smm.org/deadzone/causes/top.html)
A Dead Zone is a large region of the
ocean that is very low in oxygen,
and therefore can't support life.
Dead Zones occur along many of
the world's coastlines and are
caused by fertilizer and sewage and
other nutrients.
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
• Overexploitation of wildlife by harvesting
– Has threatened various animal and plant
species
Figure 38.3B
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
38.5
Rapid global warming is altering entire biosphere
• Burning of fossil fuels
– Is increasing the amount of CO2 and other greenhouse
gases in the air
1.05
0.90
CO2 concentration (ppm)
380
0.75
370
Temperature
0.60
360
0.45
350
0.30
340
0.15
330
CO2
0
320
–0.15
310
Figure 38.5A
–0.30
300
–0.45
1960
1965
1970
1975
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
1980
1985
Year
1990
1995
2000
2005
Temperature variation (°C)
390
Rapid global warming is altering entire biosphere
• The increase of these gases in the atmosphere
– leading to global warming
Global warming:
CO2 lets sunlight through
but retains the heat
radiated from Earth.
Human activities and natural
processes add CO2 to the
atmosphere, increasing the effect.
Photosynthesis removes
CO2 from the atmosphere,
decreasing the effect.
CO2
CO2 in the
atmosphere
CO2
CO2
Destroying rain forest and causing dead zones
in the ocean…increase global warming
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
Figure 38.5B
• Global warming may
– Change climate patterns, melt polar ice caps,
flood coastal regions
– Increase the rate of species loss
– Affect coastal communities of humans
Figure 38.5C
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
So we are destroying the Earth…
Can we do anything about it?
YEP, MANY PEOPLE ARE.
Conservation biology: Is a goal-driven science
that seeks to counter the biodiversity crisis.
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
CONSERVATION OF POPULATIONS AND SPECIES
Major Threat: Habitat degradation
– Often fragments populations, causing their
numbers to decline
Figure 38.6A, B
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
CONSERVATION OF POPULATIONS AND SPECIES
38.6 Two ways to study endangered populations
• The small-population approach
– Identifies the minimum viable population
size and focuses on preserving genetic
variation
• The declining-population approach
– Diagnoses and treats the causes of a
population’s decline
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
MANAGING AND RESTORING ECOSYSTEMS
Sustaining ecosystems and
landscapes is a conservation priority
38.8
• Conservation efforts
– Are increasingly aimed at
sustaining ecosystems and
landscapes (habitats)
Figure 38.8A, B
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
Figure 38.8C
38.7 Identifying critical habitat factors can guide
conservation efforts
• Preserving and managing critical habitat
– May help endangered species recover
Figure 38.7A–C
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
• Migratory species, both terrestrial and aquatic
– May require international protection
Figure 38.9B
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
38.9 Protected areas are established to slow biodiversity loss
• Biodiversity hot spots
– Have large concentrations of endemic species
– Provide an opportunity to protect many species in
very limited areas
Equator
Figure 38.9A
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
Preservation
The Yellowstone to
Yukon Conversation
Initiative seeks to
preserve biodiversity by
connecting protected
areas
Yellowstone to Yukon
Ecoregion
38.10
YUKON
TERRITORY
NORTHWEST TERRITORIES
ALBERTA
BRITISH
COLUMBIA
–Is an international research
and conservation effort that
seeks to connect reserves and
protect species and
ecosystems
YELLOWSTONE TO YUKON
CONSERVATION INITIATIVE
LEGEND
MONTANA
Major Highways
WASHINGTON
Protected areas
Y2Y Ecoregion
70
0
140
280 km
OREGON
Figure 38.10A
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
IDAHO
WYOMING
• Grizzly bears and gray wolves
– Are two species that may benefit from this
initiative
Figure 38.10B, C
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
Restoration
• Large-scale restoration project
– Attempt to restore damaged landscapes
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
38.12
The Kissimmee River Restoration Project
– Is restoring river flow and wetlands, and
improving water quality and wildlife habitat
Former
canal
Figure 38.12A, B
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
Protection
Zoned reserves are an attempt to reverse
ecosystem disruption
38.13
• Zoned reserves
– Are undisturbed wild-lands surrounded by
buffer zones of compatible economic
development
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
• Costa Rica
– Has established many zoned reserves
Nicaragua
Caribbean Sea
Costa
Rica
Buffer zones supply steady
lasting supply of forest products,
water, hydro electric power etc.
Supports sustainable agriculture
While maintaining 80% native
species and nature as a
resource for tourism.
National parkland
Buffer zone
Pacific Ocean
Figure 38.13A, B
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
Zoned reserves
•Work because
• They involve partnerships
– among national and local governments,
non-government organizations, and
citizens
• They are NOT damaging human welfare
– Infant mortality is down
– Life expectancy is up
– Living conditions have improved
– Literacy rate is very high
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
38.14
Sustainable development is the ultimate goal
• Sustainable development
– Seeks to improve the human condition while
conserving biodiversity
– Depends on increasing and applying ecological
knowledge as well as valuing our linkages to the
biosphere
We must understand that natural
processes sustain us.
The goal is for each generation to
inherit enough natural and
economic resources and a stable
environment.
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
Figure 38.14
Saving the Tiger
• Tigers once roamed across Asia
– But the arrival of humans brought
competition for food, and also hunters
Myanmar tiger photographed by a remote “camera trap”
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
Another example of success..
•Conservation efforts
– Are providing protection
for tigers in Myanmar so
their populations can
increase
•The efforts to save tigers
– Reflect a worldwide
struggle to preserve
biodiversity, the diversity
of living things.
Copyright © 2005 Pearson Education, Inc. Publishing as Benjamin Cummings
Hukawng Valley, Myanmar