Human Activities

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Added: November 06, 2009 This Presentation is Public 
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DEFORESTATION :DEFORESTATION In many countries, people are chopping down the forests to provide timber or space for agriculture and urbanisation for the growing population.


Slide 5:BEFORE AFTER


Slide 6:SLASH BURN AND


Slide 9:LOSS OF BIODIVERSITY EXTINCTION OF ANIMALS AND PLANTS


WEATHER AND CLIMATIC CHANGES :WEATHER AND CLIMATIC CHANGES When large scales of trees are destroyed by cutting and burning, it will reduce rainfall, transpiration rate and the rate of using carbon dioxide during photosynthesis by plants. Vast amounts of greenhouse gases such as carbon dioxide which are released during the clearing and burning of forest can prevent heat from escaping from the atmosphere. This leads to greenhouse effect and global warming.


GREENHOUSE EFFECT :GREENHOUSE EFFECT Carbon dioxide traps heat in the atmosphere and causes the temperature of the earth to rise. This leads to disruption of the weather patterns. E.g. drought, floods


Slide 17:1979 2003 THE CHANGING ARCTIC


Slide 18:SAVE MY SPECIES


Intensive Farming :Intensive Farming In order to produce more food from the land, farmers have to use more fertilisers and pesticides. However, if inorganic fertilisers are used excessively, these highly soluble nutrients will quickly leach out, ending up in surrounding rivers and lakes. This process is called eutrophication. Eutrophication is also caused by urbanisation.