Geoscience Reference
In-Depth Information
in the United States that collectively contain about 200 bil-
lion barrels of oil. Many regard successful extraction of these
fossil-fuel resources as essential to a healthy and expanding
U.S. economy. On the other hand, extracting these resourc-
es may very well have significant negative environmental im-
pacts that could even harm human health. Is this a deal that
we are willing to accept? Only time will tell.
Our last case on panda habitat also requires good
knowledge of physical geography to fully comprehend the
issue and possible outcomes. Understanding panda con-
servation requires knowledge of the geographical charac-
teristics of their habitat, such as the distribution of bamboo,
elevation, and relief. It also requires an understanding of
human population trends in the area and how expansion
of agriculture and wood fuel collection has impacted the
habitat. This case study also demonstrates how scientists
have used geographical techniques to reconstruct the
changes in habitat over time. Their studies have helped
shape conservation efforts within China and by various in-
ternational organizations in a positive way that may very
well have stabilized the giant panda population in the wild
and saved them from extinction.
S u m m a r y o f K e y C o n C e p t S
1.
An understanding of physical geography is essential to
understanding human environmental interactions around
the world. Many of the topics covered in this text, such
as solar radiation, atmospheric circulation, soils, and
plant geography, are directly related to major societal
issues.
4.
With the growing need for food, agriculture is being
practiced on a massive scale in many places, such as
the San Joaquin Valley in California and in several parts
of Australia. The clearing of native vegetation and the
use of irrigation have caused intensive soil salinization
to occur in many parts of these landscapes. This pro-
cess significantly harms soils and reduces crop yields at
a time when more food is required.
2.
Human population has grown dramatically in the past
200 years, from about 1 billion people in 1800 to approx-
imately 6.7 billion today. It is projected that the popula-
tion will reach over 9 billion by 2050. This rapid growth
is tied directly to industrialization and improvements in
human health. It poses profound questions regarding the
impact on environmental systems around the world.
5.
As a result of rising demand for oil and decreasing sup-
ply, the oil industry is systematically developing uncon-
ventional supplies such as those found in the Athabasca
oil sands in Canada and various shale plays in the United
States. Although these oil sources show great prom-
ise, extraction techniques such as open-pit mining and
fracking may have serious environmental impacts.
3.
An important ongoing and future issue is the availability
of freshwater for human consumption in many places
around the world. As population grows, more people
are moving to marginal lands where water supplies are
scarce. This scarcity in places such as Las Vegas, Ne-
vada, poses major challenges regarding sustainable
economic development in semi-arid and arid regions in
the future.
6.
A growing population has resulted in massive deforesta-
tion around the world. Such forest loss has threatened
the habitat of countless plant and animal species, such
as the giant panda in China. Conservation efforts have
the potential to stabilize these losses and even reverse
them in the coming decades.
C h e C K y o u r u n d e r S t a n d i n g
1.
Describe the overall history of human population on
Earth. When were there major growth spurts, and why
did they occur? What is the projected growth of popula-
tion in the future?
3.
Why does population growth in the developing world
make it more likely that concentrations of atmospheric
CO
2
will increase in the future?
4.
Characterize the climate of Las Vegas and describe why
this pattern occurs.
5.
What is the Colorado River Compact, and how did it in-
fluence the population of Las Vegas?
2.
What is the difference between the developed and de-
veloping world, and what are the population trends in
each of these areas?
