Threats to Rainforests

What Threats?

It’s been estimated rainforests once covered 14% of the earth’s surface but this has reduced to 6% and they may disappear altogether within 40 years. Humans intervene with rainforests to bring real or imagined benefits to themselves or the local population. Valuable minerals lie under the rainforest and land is often cleared for farming, minerals and logging. This is called deforestation. Not only wildlife destroyed but erosion and flooding occur too.

Impacts of Threats

Transportation

Better transportation means easier access to raw materials like minerals and timber. Forest resources can be transported away and sold

Infrastructure

Hospitals and education can be improved from the money gained from selling natural resources

Amazonian Indians

Five years ago there were an estimated ten million tribesmen living in the rainforest, today there is estimated only 200,000

Profits

Selling resources can be used to improve a country’s infrastructure

Land Clearance

Farming, transportation and mining can lead to deforestation. Hardwood tree take many years to grow so can be difficult to replace

Cheaper electricity

Brazil intends to deliver 50% of its power needs from dams in the Amazon and also use the dams for flood control

Fertile Soils

That make farming possible are quickly washed away when the forest is cleared. If soil ends up in rivers it can lead to flooding

Raw Materials

Tropical hardwoods such as ebony and mahogany, can be sold for a good price abroad

Loss of Animals Habitat

This occurs when trees are cut down. Deforestation can result in endangering animals and plant life, or even lead to them becoming extinct

Profits

From large-scale farming and selling resources often go back to rich countries or large companies and don’t benefit the rainforest

Water Cycle

Fewer trees means less water is stored in the roots and less water is transpired. Smaller lakes and streams could dry up and the area can become drier and suffer drought.

Soil erosion/destruction

Soil moisture is no longer protected by forest cover so dries up and nutrients evaporate. Eventually, rain washes down the soil surfaces and erosion takes place.

Reduction in River Flow

HEP dams reduce river flow and separate parts of rivers with impenetrable barriers. Fish migration is also affected.

What Is a Direct or Indirect Threat

Direct threat: clear link between one thing happening and the damage being caused to something else.

Indirect threat: unclear link between one thing happening and the damage that is caused to something else.

Direct threat	Explanation
Poverty	Countries are often driven to cut down the forest for timber and cash crops to pay off existing debt.
Debt	In LIC’s (Low Income Countries) local people are cutting down small areas of land to farm in order to make a living as there is no other alternative.
Economic development	Tropical rainforest have an array of resources available (timber, oil, gas, iron ore and gold) which are extracted by deforesting the area. Land is also cleared for growing populations.
Demand for resources	To develop their trade and economy further, the forests are sacrificed for roads and expanding cities which offer different more job opportunities to the locals.

Amazon Threats

Climate Change

As Climate change leads to warmer temperatures, species must respond if they are to survive. One way to do this is to migrate to new habitats that become suitable (and away from old ones that become unsuitable); another way is to adapt to hotter temperatures, but the speed of climate change may be too fast for some species to evolve to keep up. In some cases, if their structure permits it, species may be capable of tolerating increases in temperature, but the likelihood of this is unknown.

What has happened to the rainforest biome recently?

Your answer should include: Decreased / Biodiversity / Fallen / Logging / Exploited

List the main threats to the rainforest. Which is most important?

Your answer should include: Agriculture / Logging / Fires

What are the impacts of these threats?

Your answer should include: Economic / Social / Environmental