Geography Reference
In-Depth Information
road. The greater danger is that prices of food will rise
due to lack of availability . Price rises might also be expe-
rienced by countries that import Indian food because
there will be less of it.
The very poorest of the India' s 235 million farmers,
already malnourished, will certainly be at even greater
risk for health problems and even death. In previous
years of food shortages, there have been “rice riots”
with resultant personal injuries and property destruc-
tion. These events harm local communities and place
an even greater strain on newly required government
resources.
Those of us living in a high-tech world probably find
it difficult to grasp these circumstances and levels of des-
peration. But for millions in Asia and elsewhere, desper-
ation is still a fact of life.
layer has a different microclimate, with the upper layer
having the most light, heat, and wind. The forest' s bio-
mass is in the canopy , high above the forest floor. Leaves
appear on tree trunks at approximately 15 feet (5 m)
above ground, and this begins the canopy that reaches
upward to 100 feet (30 m) or more. Poking out of the
canopy are the tallest trees, called emergents.Diptero-
carps ,with their two-winged seeds, are said to be the
“apex of evolution.” Of grand stature, they dominate the
upper canopy and house a wealth of flora and fauna.
The middle level of the canopy is densest (Figure
2-11). It has a spectacular array of mammals, birds, and
other species. Lianas (woody climbers and vines) loop
around and between trees. These are the bane of foresters
because they can so entangle a tree that even when the
tree is completely cut down, it remains dangling, tied to
adjacent trees. Some lianas are 8 inches (20 cm) in diam-
eter. Orchids, ferns, and other epiphytes inhabit this
zone as well. Epiphytes are physically , but not nutrition-
ally , supported by other plant life.
NaturalVegetation
Natural vegetatio implies undisturbed, mature plant
communities. Major terrestrial ecosystems are called
biomes . Biomes are characterized by particular climates,
soils, plants, and animals. Climate is the most important
factor in the generation of these biotic communities.
Earth biomes are usually named for their dominant
vegetation. Because of thousands of years of occupation,
an undisturbed biome is a rarity . However, examination
of natural, model biomes helps us to understand origi-
nal vegetation and reveals the measure of human im-
pacts. The following biomes are coincident with the
climate zones of the regions of Asia under discussion in
this topic.
TROPICAL RAINFORESTS
T Tropical rain forests are most prominent in Southeast
Asia, where equatorial conditions provide plentiful year-
round moisture and consistently warm temperatures.
Here is Earth' is most diverse biome. Of 250,000 flower-
ing plant species in the world, 170,000 are tropical. Of
these, 40,000 are in Asia, with 25,000 in Malaysia and
Indonesia. Western Europe, west of Russia and north of
the Alps, has 50 indigenous species. Eastern North
America has 171. In contrast, one study in Indonesia
revealed more than 170 different plant species in a sin-
gle acre (about the size of a football field). Another 123
acre research plot on the Malay Peninsula exhibited 830
indigenous species.
Think of rain forests as having layers within which
every plant competes for sunlight and moisture. Each
Figure 2-11
T Tropical rain forest. Where light penetrates, vegetation can be
very dense. Note the lianas. Dense forest like this is often called
“jungle.” Photograph courtesy of B. A. Weightman.
 
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