Tropical Rainforest - Deforestation

Tropical Rainforest - Deforestation

1. There are 5 main causes of deforestation

   • Farming- forest is cleared to set up small farms or large cattle ranches. Often the "slash and burn" technique is used to clear the forest - vegetation is cut down and left to dry then burnt.
   • Commercial logging - trees are felled to make money.
   • Population pressure - as the population in the area increases, trees are cleared to make land for new settlements.
   • Road building - more settlements and industry lead to more roads being built. Trees along the path of the road have to be cleared to build them.
   • Mineral extraction - minerals are mined and sold to make money. Trees are cut down to expose ground and to clear access routes.

2. Environmental impacts

   • Fewer trees mean fewer habitats and food sources for animals. This reduces biodiversity as organisms either have to move or become extinct.
   • With no trees to hold the soil together, heavy rain washed away the soil (soil erosion).
   • If a lot of soil from deforested areas is washed into rivers it can kill fish, make the water undrinkable and cause flooding (as the riverbed is raised so it can't hold as much water).
   • Without a tree canopy to intercept rainfall and tree roots to absorb it, more water reaches the soil. This increases the risk of flooding and reduces soil fertility as nutrients in the soil are washed down into the earth, out of reach of the plants.
   • Without trees there's no leaf fall - so no nutrient supply to the soil which makes it less fertile.
   • Trees remove CO2 from the atmosphere when they photosynthesis, so without them less CO2 is removed.
     • Burning vegetation to clear forest produces CO2, so more CO2 in the atmosphere, increasing global warming.
   • Without trees, water isn't removed from the soil and evaporated into the atmosphere. So fewer clouds form and rainfall in the area is reduced. Reduced rainfall reduces plant growth.

3. Social impacts

   • The quality of life for some local people improves as there are more jobs.
   • There can be conflict between native people, landowners, mining companies and logging companies over use of land.
   • Some native tribes have been forced to move when trees on their land have been cleared.
   • The livelihoods of some local people are destroyed - deforestation can cause the loss of the animals and plants that they rely on to make money.

4. Economic impacts

   • Logging,farming and mining create jobs.
   • A lot of money is made from selling timber, mining and commercial farming.

5. Political impacts

   • There's pressure from foreign governments to stop deforestation.