Geoscience Reference
In-Depth Information
1,800,000
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0
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Year
A.D.
Figure 20.32 Graph of Chinese population the past 2000 years.
Note the rapid growth phases from 1650 to 1900 and be-
tween 1950 and the present. Over 1 billion people now live in the country.
(11,390 mi
2
) in 1975 to only 13,000 km
2
(5,019 mi
2
) by 1985 due
to extensive logging. Results of the third national panda survey in
2004 indicated that China's wild giant panda population included
approximately 1600 animals, which is about 40% more than pre-
vious estimates. Although hailed as good news, it was believed
that this increase is probably related to more accurate survey
methods rather than an actual increase in the number of pandas.
KEY CONCEPTS TO REMEMBER ABOUT
PANDA HABITAT AND CONSERVATION
1.
Giant pandas are members of the bear family who live in
the bamboo understory of old-growth forests in China.
They mostly eat bamboo shoots.
2.
The range of pandas once included much of southeast-
ern Asia. As a result of increased human population and
logging, they are now confined to several small areas in
south-central China, including the Wolong Nature Re-
serve. Approximately 1600 pandas live in the wild, and
they are severely threatened with extinction.
The Wolong Nature Reserve
In the past decade, a systematic effort has been made to fully
document the extent of panda habitat and to monitor its health
and distribution. Much of this effort has focused on the Wolong
Nature Reserve, which is located in the Qionglai Mountains in
the west-central part of the modern panda range (Figure 20.31
and 20.33a). The reserve was established in 1963 and is about
200,000 hectares (~494,200 acres) in size. It contains numerous
high mountains and deep valleys, with overall elevation ranging
from 1200 m to 6250 m (~3900 ft to 20,500 ft) above sea level.
The vegetation in the reserve has a distinct vertical zonation, such
as that discussed in Chapter 10, ranging from evergreen and de-
ciduous broad leaf trees at the lower elevations to subalpine co-
niferous forests at higher elevations. Given this broad ecological
range, the reserve contains over 6000 different plant and animal
species, including more than 150 giant pandas. The reserve also
includes the Wolong Giant Panda Reserve Center, which was es-
tablished in the 1980s and is thus one of the oldest research cen-
ters devoted to pandas in China. In an effort to support the wild
panda population, this research center focuses largely on giant
panda breeding and the study of bamboo ecology.
3.
Analysis of land-cover change at the Wolong Nature Re-
serve shows the patterns of forest loss and fragmenta-
tion of panda habitat in the late 20th century.
4.
Understanding the patterns and causes of panda habi-
tat loss, coupled with concerns over their status, has
led to reforms aimed at protecting them in the wild.
5.
The loss of panda habitat may be stabilizing, potentially
resulting in the increased viability of pandas in the future.
A great deal of scientific research has been conducted in
the Wolong Nature Reserve to monitor the health of the panda
habitat and the human impact on it. Much of this research
uses the remote sensing technology discussed in Chapter 2.
Figure 20.33b is a good example of a satellite image of the
Wolong Nature Reserve. This image is a composite digital el-
