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Monitoring and maintaining the environment - OCR Gateway Deforestation

Biodiversity is a measure of how many different species live in an ecosystem. Human activities like changing land use, deforestation and peat bog destruction reduce this.

Part of Biology (Single Science)Global challenges

Deforestation

For thousands of years, humans have been deforesting small areas of woodland to build their own houses or grow crops to feed their families. However, in recent years, the increase in the human and development of industrial machinery has meant that much larger areas have been cleared. This is often by large companies who deforest to provide land for cattle, rice fields and growing crops for .

Deforestation destroys the of the organisms that live there and through this kills individuals of many . Scientists estimate that over a hundred species of plant, animal and insect might be lost each day partly as a result of deforestation. This means that deforestation is causing extinctions and dramatically reducing biodiversity.

Image gallerySkip image gallerySlide 1 of 2, World map showing areas of forest in 8000 BCE, The world's forests 8000 BC

Global example - Sustainable management of the rainforest

Brazil needs to exploit the Amazon's resources to develop, so leaving the rainforest untouched is not an option. We still have a lot to learn about the rainforest and its species. For example, many medicines were found in plants that grow in the rainforest before they became commercially available.

While uncontrolled exploitation can cause irreversible damage such as loss of , , flooding and climate change, use of the rainforest can help meet the needs of Brazil's population without compromising the needs of future generations.

Possible strategies that allow humans to lessen their negative impact on the ecosystem include:

  • Agro-forestry - growing trees and crops at the same time. This lets farmers take advantage of shelter from the canopy of trees. It prevents soil erosion, and the crops benefit from the nutrients from the dead organic matter.
  • Selective logging - trees are only felled when they reach a particular height. This allows young trees a guaranteed life span and the forest will regain maturity after around 30 - 50 years.
  • Education - ensuring those involved in exploitation and management of the forest understand the consequences of their actions.
  • Afforestation - the opposite of deforestation. If trees are cut down, they are replaced to maintain the canopy.
  • Forest reserves - areas protected from exploitation.
  • Monitoring - use of satellite technology and photography to check that any activities taking place are legal and follow guidelines for sustainability.