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Biodiversity and diseases
Food contamination and food web distortion
Economical effects
Alteration to geographical landscapes
- Deforestation
- Desertification
- Erosion
- Landslide
Climatic pattern change
Ozone depletion and Acid rain
Alteration to lifestyle
Reduced visibility/clarity of air

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Photograph: Forest fires ©Department of Energy/National Renewable Energy Laboratory, US. Permission stated in the disclaimer.


Photograph: Forest fires ©AdCouncil. Permission obtained in 22 Feb 2001. E-mail message.


Photograph: Satellite image... ©Meteorological Service of Singapore. Permission obtained in August 2001. E-mail message.

 

Alteration to geographical landscapes

Deforestation

Deforestation is the degradation of forest areas in unsustainable rates, caused by human activities. 

Below is a table explaining some important pointers for deforestation:

Causes population increase, demands more lands to use for cultivation, residence and commerce areas, added by inappropriate technology
Impacts
  • increases in global greenhouse gases rate (from 1850 - 1990, deforestation contributes to 122 billion metric tons of carbon to the atmosphere)
  • reducing the evaporation and evapotranspiration processes in forest, thus decreasing precipitation rates, and makes the surface warmer, consequently lead to atmosphere warming
  • declining of biodiversity
  • erosion and soil degradation
Facts and Trends
  • lost of 6200 square miles per year from 1978 - 1986 in Brazillian Amazon forest, fell to 4800 square miles per year from 1986 - 1993

  • 16.5% (230,000 square miles) of the Amazon forest was affected by deforestation

  • an average rate of 21,000 square miles lost of forest in overall South America

  • region of Southeast Asia lost 4800 square miles per year during 1970s - 1980s

  • estimation of lost of 28 hectares forest a minute in early 1990s

  • during the past 30 years, the global forest is experiencing tropical forest deforestation rate of 20%, including 30% of Asia's forests.

  • lost of 137 species each day

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