3. • Deforestation is the removal of a forest
or stand of trees where the land is
thereafter converted to a non-forest
use. Examples of deforestation include
conversion of forestland to
farms, ranches, or urban use.
DEFORESTATION
4. HUMAN CUSES (Agustín, Felipe
C, Francisco)
Some human causes of deforestation are :
• expanding cities,
• lack of farming land,
• cattle pastures needed to graze in.
When people cut down trees to expand land, every tree
they cut down is letting out carbon dioxide that has
been stored when they have done photosynthesis.
When people need place, they kill plants, trees and
animals, as well as the habitat of these animals just to
expand their lands. logging mining
6. Deforestation
Deforestation refers to the
cutting, clearing, and removal of
rainforest or related ecosystems into less
bio-diverse ecosystems such as
pasture, cropland, or plantations.
7. Natural causes
Some of the natural causes of deforestation are:
• Forest fires: uncontrolled fire in an area of
combustible vegetation that occurs in the
countryside or a wilderness area.
• Drought: period of unusually dry weather that
persists long enough to cause environmental or
economic problems.
• Floods: the main reason that deforestation cause
floods, it is because there isn´t plants enough to
absorb the water when it rains, etc.
9. • As our understanding of the role forests play
in stabilizing global climate increases, it is
becoming clear that their destruction is only
exacerbating climate change. If we're serious
about tackling this, then preserving our
remaining ancient forests has to be a priority.
Burning forests to clear land for agriculture releases
huge amounts of greenhouse gases
10. • Mature forests store enormous quantities of carbon, both in the trees and
vegetation itself and within the soil in the form of decaying plant matter. Forests in
areas such as the Congo and the Amazon represent some of the world's largest
carbon stores on land.
• But when forests are logged or burnt, that carbon is released into the
atmosphere, increasing the amount of carbon dioxide and other greenhouse gases
and accelerating the rate of climate change. So much carbon is released that they
contribute up to one-fifth of global man-made emissions, more than the world's
entire transport sector.
• Deforestation has such a massive effect on climate change
that Indonesia and Brazil are now the third and fourth largest emitters of carbon
dioxide on the planet. This dubious honour comes not from industrial or transport
emissions, but from deforestation - up to 75 per cent of Brazil's emissions come
solely from deforestation - with the majority coming from clearing and burning
areas of the Amazon rainforest.
Carbon storehouses
12. Effects on animals
• More than half of the animal and plant
species in the world live in tropical forests.
• It destroys their natural homes and habitat
forcing them to relocate, sometimes they try
to move into residential areas looking for food
or shelter and this can be very dangerous
depending on the animal.
15. • Animals help balancing our ecosystem, food
chain and acts as a food for us .So it´s really a
shame for us to destroy our animal habitat by
cutting trees{deforestation}.
17. • Rainforests are widely believed by laymen to
contribute a significant amount of the world's
oxygen, although it is now accepted by
scientists that rainforests contribute little
net oxygen to the atmosphere and
deforestation has only a minor effect on
atmospheric oxygen levels.
• However, the incineration and burning of
forest plants to clear land releases large
amounts of CO2, which contributes to global
warming.
18. • Scientists also state that tropical
deforestation releases 1.5 billion tons of
carbon each year into the atmosphere.
• Forests are also able to extract carbon
dioxide and pollutants from the air, thus
contributing to biosphere stability.
19. Carbon Emmission
• Every time we burn fossil fuels such as
gas, coal or oil, carbon dioxide is released into
the atmosphere. In a natural carbon
cycle, carbon dioxide is re-absorbed by plants
and trees. However, we are burning fuels
where the carbon dioxide has been trapped
under the earth's surface for millions of
years, and we're doing it so quickly that plants
and trees that are alive now have no chance of
soaking it up
20. • The effect of all this extra carbon dioxide in the
atmosphere is that the overall temperature of
the planet is increasing (global warming).
Whilst the average global temperature is
increasing, on a day-to-day level the climate is
changing in unpredictable ways. To try and
reduce the risk of ever more extreme weather,
we need to reduce how much fossil fuel we are
burning. This isn't easy
22. Trees store and transpire great
quantities of water; it's one of the
reasons rainforests remain humid and
wet. Take away the trees and that store
of water is lost.
Moisture cannot be returned to the
atmosphere without the plants. Because
neither water nor nutrients can cycle in
a forest ecosystem after the trees are
cut down, extensive cutting can convert
lush forests into deserts.
23. In the water cycle there are only a few
processes that gives water back to the
atmosphere, such as
transpiration, expiration and evaporation.
Transpiration is the process by which
water is loss from plants to the
atmosphere. So, if plants are removed
there will be less water returning in the
atmosphere. This will eventually cause a
reduction in the amount of water
returning the earth's surface such as the
seas, lakes and rivers.
24. We can stop deforestation with
measures such as
• Reforestation - Forest plantations
• Forest Management / Monitoring
deforestation
• High- yield/ hybrid crops
• Sustainable practices
