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Figure 20
Corridors between habitat fragments allow safe passage for animals.
Describe
What are the advantages and disadvantages of corridors?
Corridors between habitat fragments
Conservation ecologists are maintaining and improving biodiversity by providing
corridors, or passageways, between habitat fragments. Corridors, such as those shown
in
Figure 20
, are used to connect smaller parcels of land. These corridors allow organ-
isms from one area to move safely to the other area. This creates a larger piece of land
that can sustain a wider variety of species and a wider variety of genetic variation.
However, corridors do not completely solve the problem of habitat destruction. Diseases
easily pass from one area to the next as infected animals move from one location to
another. This approach also increases edge effect. One large habitat would have fewer
edges, but often a large habitat is hard to preserve.
Legislative actions
During the 1970s, a great deal of attention was focused on destruction of the
environment and maintaining biodiversity. Laws were enacted in countries around the
world, and many treaties between countries were signed in an effort to preserve the
environment. In the United States, the Endangered Species Act was enacted in 1973. It
was designed to legally protect the species that were becoming extinct or in danger of
becoming extinct. An international treaty, the Convention on International Trade in
Endangered Species of Wild Fauna and Flora (CITES), was signed in 1973. It outlawed
the trade of endangered species and animal parts, such as ivory elephant tusks and
rhinoceros horns. Since the 1970s, many more laws and treaties have been enacted and
signed with the purpose of preserving biodiversity for future generations.
Restoring Ecosystems
Sometimes, biodiversity is destroyed in an area such that it no longer provides the
abiotic and biotic factors needed for a healthy ecosystem. For example, the soil from
cleared tropical rain forests becomes unproductive for farming after a few years. After
mining activities are completed, land might be abandoned in a condition that does not
support biodiversity. Accidental oil spills and toxic chemical spills might pollute an area
to such a degree that the native species cannot live there.
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Module 5 • Biodiversity and Conservation