Sustaining The Earth - PowerPoint PPT Presentation

Loading...

PPT – Sustaining The Earth PowerPoint presentation | free to download - id: 68b0fe-M2NlN



Loading


The Adobe Flash plugin is needed to view this content

Get the plugin now

View by Category
About This Presentation
Title:

Sustaining The Earth

Description:

Sustaining The Earth s Biodiversity Chapters 10 and 11 – PowerPoint PPT presentation

Number of Views:26
Avg rating:3.0/5.0
Slides: 64
Provided by: You
Learn more at: http://bedfordjfhs.sharpschool.net
Category:

less

Write a Comment
User Comments (0)
Transcript and Presenter's Notes

Title: Sustaining The Earth


1
Sustaining The Earths Biodiversity
  • Chapters 10 and 11

2
HUMAN IMPACTS ON TERRESTRIAL BIOMES
  • Human activities have damaged or disturbed more
    than half of the worlds terrestrial ecosystems.
  • Humans have had a number of specific harmful
    effects on the worlds deserts, grasslands,
    forests, and mountains.

3
Causes and consequences of climate change
4
The Numbers
  • We have disturbed
  • 95 of the virgin forest
  • 83 of all land surfaces
  • 98 of the plains grassland in the Midwest
  • 99 of the grasslands in California
  • 85 of the Redwood forests in California

5
HUMAN IMPACTS ON TERRESTRIAL BIODIVERSITY
  • We have depleted and degraded some of the earths
    biodiversity and these threats are expected to
    increase.

Figure 10-2
6
Why Should We Care About Biodiversity?
  • Use Value For the usefulness in terms of
    economic and ecological services.
  • Nonuse Value existence, aesthetics, bequest for
    future generations.

Figure 10-3
7
Why Biodiversity?
  • Biodiversity maintains an ecosystem!!!!!

8
Core Case Study The Passenger Pigeon - Gone
Forever
  • Once the most numerous bird on earth.
  • In 1858, Passenger Pigeon hunting became a big
    business.
  • By 1900 they became extinct from over-harvest and
    habitat loss.

Figure 11-1
9
SPECIES EXTINCTION
  • Species can become extinct
  • Locally A species is no longer found in an area
    it once inhabited but is still found elsewhere in
    the world.
  • Ecologically Occurs when so few members of a
    species are left they no longer play its
    ecological role.
  • Globally (biologically) Species is no longer
    found on the earth.

10
Global Extinction
  • Some animals have become prematurely extinct
    because of human activities.

Figure 11-2
11
SPECIES EXTINCTION
  • Some species have characteristics that make them
    vulnerable to ecological and biological
    extinction.

Figure 11-4
12
SPECIES EXTINCTION
  • Scientists use measurements and models to
    estimate extinction rates.
  • The International Union for the Conservation of
    Nature and Natural Resources (IUCN) publishes an
    annual Red List, listing the worlds threatened
    species.
  • The 2004 Red List contains 15,589 species at risk
    for extinction.

Figure 11-5
13
SPECIES EXTINCTION
  • Percentage of various species types threatened
    with premature extinction from human activities.

Figure 11-5
14
SPECIES EXTINCTION
  • Scientists use models to estimate the risk of
    particular species becoming extinct or endangered.

Figure 11-6
15
IMPORTANCE OF WILD SPECIES
  • We should not cause the premature extinction of
    species because of the economic and ecological
    services they provide.
  • Some believe that each wild species has an
    inherent right to exist.
  • Some people distinguish between the survival
    rights among various types of species (plants vs.
    animals).

16
Endangered and Threatened Species Ecological
Smoke Alarms
  • Endangered species so few individual survivors
    that it could soon become extinct.
  • Threatened species still abundant in its natural
    range but is likely to become endangered in the
    near future.

Figure 11-3
17
HABITAT LOSS, DEGRADATION, AND FRAGMENTATION
  • Conservation biologists summarize the most
    important causes of premature extinction as
    HIPPO
  • Habitat destruction, degradation, and
    fragmentation
  • Invasive species
  • Population growth
  • Pollution
  • Overharvest

18
HABITAT LOSS, DEGRADATION, AND FRAGMENTATION
  • The greatest threat to a species is the loss,
    degradation, and fragmentation of where it lives.

Figure 11-7
19
HABITAT LOSS, DEGRADATION, AND FRAGMENTATION
  • Reduction in ranges of four wildlife species,
    mostly due to habitat loss and overharvest.

Figure 11-8
20
Case Study A Disturbing Message from the Birds
  • Human activities are causing serious declines in
    the populations of many bird species.

Figure 11-9
21
Case Study A Disturbing Message from the Birds
  • The majority of the worlds bird species are
    found in South America.
  • Threatened with habitat loss and invasive species.

Figure 11-10
22
INVASIVE SPECIES
  • Many nonnative species provide us with food,
    medicine, and other benefits but a a few can wipe
    out native species, disrupt ecosystems, and cause
    large economic losses.

Kudzu vine was introduced in the southeastern
U.S. to control erosion. It has taken over native
species habitats.
Figure 11-A
23
INVASIVE SPECIES
  • Many invasive species have been introduced
    intentionally.

Figure 11-11
24
INVASIVE SPECIES
  • Many invasive species have been introduced
    unintentionally.

Figure 11-11
25
INVASIVE SPECIES
  • The Argentina fire ant was introduced to Mobile,
    Alabama in 1932 from South America.
  • Most probably from ships.
  • No natural predators.

Figure 11-12
26
INVASIVE SPECIES
  • Prevention is the best way to reduce threats from
    invasive species, because once they arrive it is
    almost impossible to slow their spread.

Figure 11-13
27
Characteristics of Successful Invader Species
Characteristics of Ecosystems Vulnerable to
Invader Species
Climate similar to habitat of invader
Absence of predators on invading species Early
successional systems Low diversity of
native species Absence of fire Disturbed by
human activities
High reproductive rate, short generation
time (r-selected species) Pioneer species
Long lived High dispersal rate Release
growth-inhibiting chemicals into soil
Generalists High genetic variability
Fig. 11-13, p. 236
28
POPULATION GROWTH, POLLUTION, AND CLIMATE CHANGE
  • Population growth, affluenza, and pollution have
    promoted the premature extinction of some
    species.
  • Projected climate change threatens a number of
    species with premature extinction.

29
Pollution
  • Each year pesticides
  • Kill about 1/5th of the U.S. honeybee colonies.
  • 67 million birds.
  • 6 -14 million fish.
  • Threaten 1/5th of the U.S.s endangered and
    threatened species.

Example of biomagnification of DDT in an aquatic
food chain.
Figure 11-15
30
OVEREXPLOITATION
  • Some protected species are killed for their
    valuable parts or are sold live to collectors.
  • Killing predators and pests that bother us or
    cause economic losses threatens some species with
    premature extinction.
  • Legal and illegal trade in wildlife species used
    as pets or for decorative purposes threatens some
    species with extinction.

31
OVEREXPLOITATION
  • Rhinoceros are often killed for their horns and
    sold illegally on the black market for decorative
    and medicinal purposes.

Figure 11-16
32
Case Study Rising Demand for Bushmeat in Africa
  • Bushmeat hunting has caused the local extinction
    of many animals in West Africa.
  • Can spread disease such as HIV/AIDS and ebola
    virus.

Figure 11-17
33
PROTECTING WILD SPECIES LEGAL AND ECONOMIC
APPROACHES
  • International treaties have helped reduce the
    international trade of endangered and threatened
    species, but enforcement is difficult.
  • One of the most powerful is the 1975 Convention
    on International Trade of Endangered Species
    (CITES).
  • Signed by 169 countries, lists 900 species that
    cannot be commercially traded.

34
Endangered Species
  • 1973 Endangered Species Act protected species in
    danger of extinction
  • Species in such small numbers that extinction is
    imminent
  • Species that are threatened by environmental
    factors that could decimate the population

35
Case Study The U.S. Endangered Species Act
  • One of the worlds most far-reaching and
    controversial environmental laws is the 1973 U.S.
    Endangered Species Act (ESA).
  • ESA forbids federal agencies (besides defense
    department) to carry out / fund projects that
    would jeopardize an endangered species.
  • ESA makes it illegal for Americans to engage in
    commerce associated with or hunt / kill / collect
    endangered or threatened species.

36
Case Study The U.S. Endangered Species Act
  • Biodiversity hotspots in relation to the largest
    concentrations of rare and potentially endangered
    species in the U.S.

Figure 11-18
37
Endangered Species
  • Because of scarcity of inspectors, probably no
    more than 1/10th of the illegal wildlife trade in
    the U.S. is discovered.

Figure 11-19
38
Endangered Species
  • Congress has amended the ESA to help landowners
    protect species on their land.
  • Some believe that the ESA should be weakened or
    repealed while others believe it should be
    strengthened and modified to focus on protecting
    ecosystems.
  • Many scientists believe that we should focus on
    protecting and sustaining biodiversity and
    ecosystem function as the best way to protect
    species.

39
How Would You Vote?
  • Should the Endangered Species Act be modified to
    protect and sustain the nation's overall
    biodiversity?
  • a. No. Protecting entire habitats will only
    further interfere with the rights of landowners.
  • b. Yes. Protecting endangered habitats is more
    efficient and effective than saving individual
    species.

40
ECOLOGICAL RESTORATION
  • Five basic science-based principles for
    ecological restoration
  • Identify cause.
  • Stop abuse by eliminating or sharply reducing
    factors.
  • Reintroduce species if necessary.
  • Protect area form further degradation.
  • Use adaptive management to monitor efforts,
    assess successes, and modify strategies.

41
ECOLOGICAL RESTORATION
  • Restoration
  • Rehabilitation
  • Replacement
  • Creating artificial ecosystems

42
ECOLOGICAL RESTORATION
  • Restoration trying to return to a condition as
    similar as possible to original state.
  • Rehabilitation attempting to turn a degraded
    ecosystem back to being functional.

43
ECOLOGICAL RESTORATION
  • Replacement replacing a degraded ecosystem with
    another type of ecosystem.
  • Creating artificial ecosystems such as
    artificial wetlands for flood reduction and
    sewage treatment.

44
PROTECTING WILD SPECIES THE SANCTUARY APPROACH
  • The U.S. has set aside 544 federal refuges for
    wildlife, but many refuges are suffering from
    environmental degradation.

Pelican Island was the nations first wildlife
refuge.
Figure 11-20
45
PROTECTING WILD SPECIES THE SANCTUARY APPROACH
  • Gene banks, botanical gardens and using farms to
    raise threatened species can help prevent
    extinction, but these options lack funding and
    storage space.
  • Zoos and aquariums can help protect endangered
    animal species by preserving some individuals
    with the long-term goal of reintroduction, but
    suffer from lack of space and money.

46
RECONCILIATION ECOLOGY
  • Reconciliation ecology involves finding ways to
    share places we dominate with other species.
  • Replacing monoculture grasses with native
    species.
  • Maintaining habitats for insect eating bats can
    keep down unwanted insects.
  • Reduction and elimination of pesticides to
    protect non-target organisms (such as vital
    insect pollinators).

47
Using Reconciliation Ecology to Protect Bluebirds
  • Putting up bluebird boxes with holes too small
    for (nonnative) competitors in areas where trees
    have been cut down have helped reestablish
    populations.

Figure 11-B
48
Core Case Study Reintroducing Wolves to
Yellowstone
  • Endangered Species
  • 1850-1900 two million wolves were destroyed.
  • Keystone Species
  • Keeps prey away from open areas near stream
    banks.
  • Vegetation reestablishes.
  • Species diversity expands.

Figure 10-1
49
Keystone species
  • Keystone species are those organisms that play a
    major role (niche) in the functionality of an
    ecosystem

50
Wolves Keystone?
  • After the wolf population was nearly destroyed,
    there was an increase in grazing herds
  • Moose, deer, antelope
  • These herds decimated the vegetation because
    their natural predators were in such small numbers

51
Fish Wildlife
  • 1987 US Fish and Wildlife re-introduced wolves to
    Yellowstone National Park.
  • Resistance by local farmers
  • Carrying capacity of 110-150 wolves
  • Since 1987, the herds of grazing animals under
    control, vegetation is rebounding and coyotes are
    no longer a threat!

52
Will Restoration Encourage Further Destruction?
  • There is some concern that ecological restoration
    could promote further environmental destruction
    and degradation.
  • Suggesting that any ecological harm can be
    undone.
  • Preventing ecosystem damage is far cheaper than
    ecological restoration.

53
WHAT CAN WE DO?
  • Eight priorities for protecting biodiversity
  • Take immediate action to preserve worlds
    biological hot spots.
  • Keep intact remaining old growth.
  • Complete mapping of worlds biodiversity for
    inventory and decision making.
  • Determine worlds marine hot spots.
  • Concentrate on protecting and restoring lake and
    river systems (most threatened ecosystems).

54
WHAT CAN WE DO?
  • Ensure that the full range of the earths
    ecosystems are included in global conservation
    strategy.
  • Make conservation profitable.
  • Initiate ecological restoration products to heal
    some of the damage done and increase share of
    earths land and water allotted to the rest of
    nature.

55
What Can You Do?
Sustaining Terrestrial Biodiversity
Adopt a forest. Plant trees and take care
of them. Recycle paper and buy recycled paper
products. Buy sustainable wood and wood
products. Choose wood substitutes such as
bamboo furniture and recycled plastic outdoor
furniture, decking, and fencing. Restore a
nearby degraded forest or grassland. Landscape
your yard with a diversity of plants natural to
the area. Live in town because suburban sprawl
reduces biodiversity.
Fig. 10-27, p. 219
56
NATIONAL PARKS
  • Countries have established more than 1,100
    national parks, but most are threatened by human
    activities.
  • Local people invade park for wood, cropland, and
    other natural resources.
  • Loggers, miners, and wildlife poachers also
    deplete natural resources.
  • Many are too small to sustain large-animal
    species.
  • Many suffer from invasive species.

57
Case Study Stresses on U.S. National Parks
  • Overused due to popularity.
  • Inholdings (private ownership) within parks
    threaten natural resources.
  • Air pollution.

Figure 10-23
58
  • Suggestions for sustaining and expanding the
    national park system in the U.S.

Figure 10-24
59
NATURE RESERVES
  • Ecologists call for protecting more land to help
    sustain biodiversity, but powerful economic and
    political interests oppose doing this.
  • Currently 12 of earths land area is protected.
  • Only 5 is strictly protected from harmful human
    activities.
  • Conservation biologists call for full protection
    of at least 20 of earths land area representing
    multiple examples of all biomes.

60
NATURE RESERVES
  • Large and medium-sized reserves with buffer zones
    help protect biodiversity and can be connected by
    corridors.
  • Costa Rica has consolidated its parks and
    reserves into 8 megareserves designed to sustain
    80 if its biodiversity.

Figure 10-10B
61
NATURE RESERVES
  • Geographic Information System (GIS) mapping can
    be used to understand and manage ecosystems.
  • Identify areas to establish and connect nature
    reserves in large ecoregions to prevent
    fragmentation.
  • Developers can use GIS to design housing
    developments with the least environmental impact.

62
NATURE RESERVES
  • We can prevent or slow down losses of
    biodiversity by concentrating efforts on
    protecting global hot spots where significant
    biodiversity is under immediate threat.
  • Conservation biologists are helping people in
    communities find ways to sustain local
    biodiversity while providing local economic
    income.

63
NATURE RESERVES
  • Wilderness is land legally set aside in a large
    enough area to prevent or minimize harm from
    human activities.
  • Only a small percentage of the land area of the
    United States has been protected as wilderness.
About PowerShow.com