11-6 Tropical Deforestation

How Fast Are Tropical Forests Being Cleared and Degraded, and Why Should We Care? Protecting the Priceless

Climatic and biological data suggest that mature tropical forests once covered at least twice as much area as they do today, with most of the destruction occurring since 1950.

Studies indicate that more than half of the world’s species of terrestrial plants and animals live in tropical rain forests. Brazil has about 30% of the world’s remaining tropical rain forest in the vast Amazon basin, which is about two-thirds the size of Canada.

There are disagreements about how rapidly tropical forests are being deforested and degraded because of three factors:

  1. It is difficult to interpret satellite images.

  2. Some countries hide or exaggerate deforestation rates for political and economic reasons.

  3. Governments and international agencies define forest, deforestation, and forest degradation in different ways.

Most biologists believe that cutting and degrading most remaining old-growth tropical forests is a serious global environmental problem because of the important ecological and economic services they provide.

What Causes Tropical Deforestation and Degradation? The Big Five

Tropical deforestation results from a number of interconnected primary and secondary causes. Population growth and poverty combine to drive subsistence farmers and the landless poor to tropical forests, where they try to grow enough food to survive.

Government subsidies can accelerate deforestation by making timber or other tropical forest resources cheap, relative to the economic value of the ecological services they provide.

The depletion and degradation of a tropical forest begins when a road is cut deep into the forest interior for logging and settlement and hunters are hired to kill wild animals to provide loggers and other work crews with meat.

After the best timber has been removed, timber companies often sell the land to ranchers. Within a few years they typically overgraze it and sell it to settlers who have migrated to the forest hoping to grow enough food to survive. Then they move their land-degrading ranching operations to another forest area.

Healthy rain forests do not burn. But increased logging, settlements, grazing, and farming along roads built in these forests results in fragments of forest that dry out.

Solutions: How Can We Reduce Deforestation and Degradation of Tropical Forests? Prevention Is Best

Analysts have suggested various ways to protect tropical forests and use them more sustainably:

  • One method is to help new settlers in tropical forests learn how to practice small-scale sustainable agriculture and forestry.

  • Another approach is to sustainably harvest some of the renewable resources such as fruits and nuts in rain forests.

  • Another approach is to use debt-for-nature swaps to make it financially profitable for countries to protect tropical forests.

  • Another important tool is using an international system for evaluating and certifying tropical timber produced by sustainable methods. Loggers can also use gentler methods for harvesting trees.

Solutions: The Incredible Neem Tree

The neem tree is a broadleaf evergreen member of the mahogany family. This remarkable tropical species, native to India and Burma, is ideal for reforestation because it can grow to maturity in only 5–7 years. It also contains various natural pesticides. Chemicals from its leaves and seeds can repel or kill more than 200 insect species, including termites, gypsy moths, locusts, boll weevils, and cockroaches.

Additionally, neem-seed oil evidently acts as a strong spermicide and may help in the development of a much-needed male birth control pill.

Despite its numerous advantages, ecologists caution against widespread planting of neem trees outside its native range. As a non-native species, it could take over and displace native species because of its rapid growth and resistance to pests.