Geoscience Reference
In-Depth Information
are important sources of carbon storage and play key roles in both regional and
global climates.
Unfortunately, this great diversity of flora and fauna, forest products, and medi-
cines is under tremendous threat. Tropical forests are disappearing at an alarming
rate. Despite growing international concern, tropical forests continue to be destroyed
at a pace exceeding 80,000 ac (32,000 ha) per day. Much of the remaining forests
have been affected by human activities and no longer retain their original biodiver-
sity. Clearing these forests affects biodiversity through habitat destruction, fragmen-
tation of formally contiguous habitat, and increased edge effects. Deforestation of
tropical forests has a global impact through species extinction, the loss of important
ecosystem services and renewable resources, and the reduction of carbon sinks. This
destruction, however, can be slowed, stopped, and in some cases even reversed.
Tropical forest loss is due to a complex combination of causes. Land use conver-
sion for farming and ranching activities has led to the loss of forests, particularly in
the Neotropics and Southeast Asia. Legal and illegal logging of rainforest trees
through clear-cutting and selective cutting destroys forests and wildlife habitats, as
well as changes the microclimate of the area. Fires in nearby cleared areas can spread
to forests that are ill equipped to survive under these conditions. These changes influ-
ence surrounding forested areas, leading to negative feedback processes that further
amplify the effects of local forest loss. Increases in population lead to increased need
for land for settlements, as well as resources such as fuelwood and meat. Hunting
contributes to the loss of many forest species, particularly large mammals.
Most of the tropical forests of the world lie in developing countries where popu-
lation increases and economic pressures often outweigh the need to conserve the
forest. Extraction of valuable minerals, gold, oil, and trees can provide temporary
economic relief to these countries. The rates of extraction are unsustainable, how-
ever, and can lead to the total loss of forest and any potential revenue that an intact
forest could have provided in the future.
As the world's tropical forests continue to disappear, considerable effort is
needed to slow or stop these losses. International nongovernmental organizations
such as the World Wildlife Fund, Conservation International, and the Rainforest
Action Network are a few of the groups working on the problem. National and
local governments and local community and conservation groups are involved in
the preservation, protection, and sustainable harvest of these areas. As there are
multiple factors causing the destruction of tropical forests, there must be multiple
approaches to stop or lessen deforestation.
National and local parks and reserves can be successful if they are properly
funded and if local communities are involved in the process of protecting local for-
ests. Both large and small reserves can be important in supporting the diverse flora
and fauna of the forests, smaller reserves can serve as corridors between larger
areas allowing for the dispersal and migration of forest species. Reserves of this sort
have been successful in Costa Rica, Bolivia, and Australia. In many areas, how-
ever, creating parks and reserves has neither stopped forest clearing by illegal log-
gers and developers nor improved the quality of living or economic opportunities
