Savanna BiomeThorntree and Tropical ScrubThe Thorntree and Tropical Scrub is characterized by short, thorny trees and shrubs. Trees The vegetation may form a continuous cover eliminating grasses. This vegetation formation is a response to a longer, and more intense drought period.
The thorntree and tropical scrub has suffered
under the misuse of human activity. Overgrazing has reduced the
capacity of the system to withstand the erosive forces of wind,
and to a lesser extent water. Without the protective restraint
plants, soil and sand, along with valuable soil nutrients, can
blow free from the surface. Deserts are rapidly encroaching and
replacing the savannas and steppe grasslands. Many years of
prolonged drought combined with human pressures on the biome
increases the likelihood for desertification of these areas.
Midlatitude Savanna
A Midlatitude savanna is sometimes called a parkland. Here, prairie vegetation is broken by patches or ribbons of broadleaf trees. The midlatitude savanna is located in a transitional area between the humid continental and midlatitude steppe climates. Parkland often is a step in the successionary evolution of plant communities on abandoned farm fields of the eastern United States. For more see "Prairie Parkland (Temperate) Province ". Human activities and the savanna biomeMany animals of the savanna biome like the rhinoceros are endangered and threatened
with extinction due to hunting and habitat loss. The most species of
elephants ere in danger of
extinction due to poaching for their ivory tusks. Several means to protect these animals
have been tried, even removal of the rhinoceros's horns and the elephant's tusks.
Many countries have banned the sale of ivory to discourage
poaching. But some countries have argued for the temporary lifting
of such bans to sell stockpiled ivory from seizures. Yet lifting
such bans may encourage further poaching. The NPR Morning
Edition "Elephant
Poaching on the Rise"
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Figure BE.34 Livestock grazing severely damages the thorntree savanna leading to
problems of desertification. Burkina Faso* (Picture credit:
Carolyn
Redenius, United Nations)
Figure
BE.35 Pinon-Juniper savanna of northern New Mexico.
segment from Jan. 17, 2000 (5:20) reports on the rise of elephant
poaching as a result of the lifting of the ban on ivory sale for a
few African countries. 