Essentials of Ecology

(Kiana) #1

CONCEPTS 10-5A, 10-5B, AND 10-5C 239


eas in the lower 48 states are threatened habitat islands
in a sea of development.
Scattered blocks of public lands with a total area
roughly equal to that of the U.S. state of Montana
could qualify for designation as wilderness. About 60%
of such land in the national forests. For more than
20 years, these areas were temporarily protected un-
der the Roadless Rule—a federal regulation that put
undeveloped areas of national forests off-limits to road
building and logging while they were evaluated for wil-
derness protection.
For decades, politically powerful oil, gas, mining,
and timber industries have sought entry to these areas—
which are owned jointly by all citizens of the United
States—to develop resources there. Their efforts paid off

in 2005 when the secretary of the interior ended protec-
tion of roadless areas within the national forest system
that were being considered for classification as wilder-
ness. The secretary also began allowing states to classify
old cow paths and off-road vehicle trails as roads (Fig-
ure 10-22), which would disqualify their surrounding
areas from protection as wilderness.

THINKING ABOUT
Protecting Wolves and Wild Lands
How do you think protecting wolves, in part by
reintroducing them to areas such as Yellowstone
National Park (Core Case Study), helps to protect the forest
areas where they live?

10-5 What Is the Ecosystem Approach to Sustaining

Biodiversity?

CONCEPT 10-5A We can help to sustain biodiversity by identifying severely
threatened areas and protecting those with high plant diversity (biodiversity
hotspots) and those where ecosystem services are being impaired.
CONCEPT 10-5B Sustaining biodiversity will require a global effort to rehabilitate
and restore damaged ecosystems.
CONCEPT 10-5C Humans dominate most of the earth’s land, and preserving
biodiversity will require sharing as much of it as possible with other species.

▲▲▲


We Can Use a Four-Point Strategy


to Protect Ecosystems


Most biologists and wildlife conservationists believe that
we must focus more on protecting and sustaining eco-
systems, and the biodiversity contained within them,
than on saving individual species. Their goals certainly
include preventing premature extinction of species, but
they argue the best way to do that is to protect threat-
ened habitats and ecosystem services. This ecosystems
approach generally would employ the following four-
point plan:


  • Map global ecosystems and create an inventory of
    the species contained in each of them and the eco-
    system services they provide.

  • Locate and protect the most endangered ecosys-
    tems and species, with emphasis on protecting
    plant biodiversity and ecosystem services.

  • Seek to restore as many degraded ecosystems as
    possible.

  • Make development biodiversity-friendly by provid-
    ing significant financial incentives (such as tax
    breaks and write-offs) and technical help to private
    landowners who agree to help protect endangered
    ecosystems.


Some scientists have argued that we need new laws
to embody this strategy. In the United States, for exam-
ple, there is support for amending the Endangered Spe-
cies Act, or possibly even replacing it with a new law
focused on protection of ecosystems and biodiversity.

Protecting Global Biodiversity


Hotspots Is an Urgent Priority


In reality, few countries are physically, politically, or fi-
nancially able to set aside and protect large biodiversity
reserves. To protect as much of the earth’s remaining
biodiversity as possible, some conservation biologists
urge adoption of an emergency action strategy to iden-
tify and quickly protect biodiversity hotspots (Con-
cept 10-5A)—an idea first proposed in 1988 by environ-
mental scientist Norman Myers. (See his Guest Essay
on this topic at CengageNOW.) These “ecological arks”
are areas especially rich in plant species that are found
nowhere else and are in great danger of extinction.
These areas suffer serious ecological disruption, mostly
because of rapid human population growth and the re-
sulting pressure on natural resources. (See Case Study
p. 240.) Myers and his colleagues at Conservation
International relied primarily on the diversity of plant
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