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The vast majority of the world's forests are no more than
small or highly disturbed pieces of the fully functioning ecosystems
they once were.
In contrast, the world's frontier forests — large, ecologically
intact, and relatively undisturbed natural forests — are likely
to survive indefinitely without human intervention.
- Forests cover about a quarter of the world's land surface, excluding
Greenland and Antarctica. Global forest cover has been reduced
by 20 percent since pre-agricultural times, and possibly as much
as 50 percent.
- Forest area has increased slightly since 1980 in industrial
countries, but has declined by almost 10 percent in developing
countries. Tropical deforestation probably exceeds 130,000 square
kilometers a year.
- Less than 40 percent of forests globally are relatively undisturbed
by human action. The great majority of forests in the industrial
countries, except Canada and Russia, are reported to be in "semi-natural" condition or converted to plantations.
- Many developing countries today rely on timber for export earnings.
At the same time, millions of people in tropical countries still
depend on forests to meet their every need.
- The greatest threats to forest extent and condition today are
conversion to other forms of land use and fragmentation by agriculture,
logging, and road construction. Logging and mining roads appear
to lead the way in opening up intact forest to pioneer settlement
and increases in hunting, poaching, fires, and exposure of flora
and fauna to pest outbreaks and invasive species.
Source: World Resources 2000-2001
In Rivers Of Destiny,
journey to four major river systems of the world to investigate environmental
problems facing those whose lives depend upon the health of their
river. Read the full description
of this program or watch a video clip.
In On the Brink, examine how severe environmental problems can lead to political crises and increased hostilities around the world. Read the full description
of this program or watch a video clip.
In Hot Zones, see how the increased spread of infectious diseases has altered global and local ecosystems. Read the full description
of this program or watch a video clip.
Read Stories of Hope
from the Journey to Planet Earth series focusing on forest ecosystems:
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