Threats to Tropical Rainforests
Tropical rainforests are disappearing at an alarming rate. Between 1990 and 2020, the world lost approximately 420 million hectares of forest — an area larger than the entire European Union. While deforestation has slowed in some regions, it has accelerated in others. This lesson examines the causes, rates and devastating impacts of tropical rainforest destruction, with a focus on the three countries losing the most forest: Brazil, Indonesia and the Democratic Republic of the Congo (DRC).
Causes of Tropical Rainforest Deforestation
Deforestation is driven by a combination of economic, social and political factors. In almost every case, the underlying driver is the demand for land or resources from growing populations and expanding global markets.
1. Commercial Agriculture — Cattle Ranching
Cattle ranching is the single largest driver of deforestation in the Amazon, responsible for approximately 80% of all deforestation in Brazil. The process is straightforward:
- Forest is cleared, usually by slash-and-burn methods (cutting trees and setting fire to the remaining vegetation)
- The ash temporarily fertilises the soil
- Grass is planted for cattle pasture
- After 5–10 years, the soil is exhausted and the rancher moves to clear new forest
- Brazil has approximately 215 million cattle — the largest commercial herd in the world
- Much of the beef is exported to Europe, China and the Middle East
2. Commercial Agriculture — Palm Oil and Soy
- Palm oil is the most widely used vegetable oil in the world, found in approximately 50% of all supermarket products (food, cosmetics, cleaning products, biofuel). Indonesia and Malaysia produce 85% of the world's palm oil, and vast areas of rainforest in Borneo and Sumatra have been cleared for plantations.
- Soy production in Brazil has expanded massively, often into areas of former rainforest or cerrado (savanna). Brazil is the world's largest soy exporter, producing over 130 million tonnes per year. Soy is primarily used for animal feed in the global meat industry.
3. Logging
- Commercial logging targets valuable hardwood species like mahogany, teak and ebony. A single mahogany tree can be worth 10,000–15,000 on the international market.
- Selective logging removes the most valuable trees, but the process of felling and extracting them damages surrounding trees — for every tree extracted, an estimated 10–30 surrounding trees are damaged.
- Illegal logging is a major problem, particularly in the DRC, Myanmar and Indonesia. The illegal timber trade is worth an estimated $50–150 billion per year globally.
4. Subsistence Farming
In the DRC and parts of South-East Asia, subsistence farmers clear small plots of forest using slash-and-burn techniques to grow crops for their families:
- The cleared plot is farmed for 2–3 years until soil fertility declines
- The farmer then moves to a new plot, allowing the old one to regenerate (this is called shifting cultivation)
- Traditionally, this was sustainable because population densities were low and forests had time to recover
- However, growing populations mean shorter fallow periods, preventing full forest recovery
5. Road Building
Roads are the arteries of deforestation. Once a road is built into previously inaccessible forest, settlers, loggers and farmers follow:
- The Trans-Amazonian Highway (BR-230), built in the 1970s, opened up vast areas of the Amazon to colonisation
- In a pattern known as "fishbone deforestation", secondary roads branch off the main highway, with settlers clearing forest on either side
- Satellite imagery shows that 95% of deforestation in the Amazon occurs within 5.5 km of a road
6. Mining
- The Amazon contains vast mineral deposits including iron ore, gold, bauxite (aluminium), manganese and tin
- The Carajás Mine in the Brazilian Amazon is the world's largest iron ore mine, covering an area of 900 km²
- Mining not only destroys the forest directly but causes secondary damage through pollution of rivers with heavy metals (mercury from gold mining), sedimentation and road building
7. Hydroelectric Power
- Brazil's Belo Monte Dam on the Xingu River (a tributary of the Amazon) flooded approximately 500 km² of forest
- While hydroelectric power is renewable, the reservoirs created by large dams destroy vast areas of forest and displace indigenous communities
Rates of Deforestation: Key Statistics
| Country | Forest Area Lost (2001–2022) | Key Drivers | Current Trend |
|---|
| Brazil | ~50 million hectares | Cattle ranching, soy, logging, mining | Accelerated 2019–2022 under Bolsonaro; declining since 2023 under Lula |
| Indonesia | ~28 million hectares | Palm oil, logging, paper/pulp industry | Slowing due to moratorium on new concessions (since 2011) |
| DRC | ~15 million hectares | Subsistence farming, charcoal production, logging, mining | Accelerating — now has the highest rate of primary forest loss |
Exam Tip: Learn specific statistics for at least two countries. In Paper 3, you may be given data about deforestation rates and asked to compare or evaluate. Having your own statistics to add to the pre-released material will strengthen your answers.
Impacts of Tropical Rainforest Deforestation
The impacts of deforestation are far-reaching, affecting local communities, national economies and the global climate.
Environmental Impacts