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Forest
Myth-
conceptions? | | |
 ENVIRONMENT
 "Environment"
means forests?
The "environment" is a catch-all term
that refers to the external conditions that act upon people.
It includes physical, chemical and biological aspects,
as well as social, cultural, economic and political aspects.
Sometimes one refers to
the green or natural environment,
and the brown or built environment.
Forests thus form part of our natural environment.
Often the word environment is used
to talk about natural resources,
which can be confusing.
Forests conserve
water?
Since forests need water to grow,
and recirculate the water back into the atmosphere,
they help to maintain the rainfall that falls on them.
The tree roots, ground vegetation, and humus also act as a sponge
which slows down the drainage of excess water from the forest land into rivers.
Thus forests help to regulate the amount of water that flows in rivers.
However,
other types of vegetation, such as grasses, can do this equally well.
Forests are the
lungs of the earth?
A confusing claim!
Our lungs take in oxygen, and give out carbon dioxide.
Forests do two things.
As they grow, they use the sun’s energy and carbon dioxide
to produce carbohydrates needed for growth.
This is the process of photosynthesis.
Oxygen is a “waste” product that enters the atmosphere.
But as trees die and decay,
they are broken down into carbon dioxide again and oxygen is used up.
This is the process of respiration.
In mature forests, the two processes are in balance,
so that there is no net change
in the amount of carbon dioxide and oxygen in the air.
It is not certain how the atmospheric oxygen came to be there,
but it seems to have been produced and maintained
by the photosynthesis of marine organisms,
not forests.
Forests help to
lock up carbon
As trees grow, they absorb carbon dioxide and store the carbon.
When the tree dies and decays, the carbon is released.
Forests, whether natural or planted,
only act as a permanent stores if they are allowed to regenerate.
If trees are harvested, the amount of carbon stored can be increased
provided that the timber is used in, say, buildings and does not decay.
Of course,
the proper solution to excessive CO2
is to reduce the emissions at source.
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