Download 樹木、蝴蝶和 人的關係 Trees, Butterflies and Humans

樹木、蝴蝶和
人的關係
Trees, Butterflies
and Humans
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樹木、蝴蝶和人的關係
Trees, Butterflies and Humans
Living in the city, we seem to be removed
from nature. Trees, however, are an
invaluable part of our lives. Trees provide
us with environmental protection, as well as
being the source for many for our essential
day to day products.
Trees and Humans
People and animals depend on trees and
plants for oxygen. As you breathe in, your
body uses oxygen. As you breathe out, you
expel carbon dioxide. In photosynthesis,
trees can do the opposite. They take in
carbon dioxide, and then release oxygen
(which also helps clean the air). Trees can
absorb harmful pollutants from the air, and
they store carbon, reducing air pollution.
Trees with thick canopies can act as noise
barriers, helping to block unwanted noise.
Trees can screen against strong winds and
sunshine. Their leaves regulate temperature
and humidity through transpiration, making
the environment more comfortable for us.
Trees are good for the environment and
add vitality to our cities. Trees in water
catchments help to trap soil and prevent
pollution, protecting our water sources.
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Many of our resources come from trees.
They provide essential products such as
fruit, nuts, timber and many other products
we use every day such as furniture and
paper. Different parts of certain trees can
be modified to make medicines; Aspirin
originally came from the bark of a Willow
tree. Quinine, the cure for malaria, comes
from the bark of Cinchona trees. We
depend so much on trees in our daily lives.
Butterflies and Trees
Butterfly caterpillars depend on leaves. For
example, Plains Cupid (Chilades pandava)
caterpillars feed mainly on Cycas. Flowers
provide nectar for butterflies. Tree sap
and rotten fruits can also be their favourite
f o o d s . A s b u t t e r f l i e s s i p n e c t ar , t h e y
spread pollen and therefore, help trees to
reproduce.
In addition to being food sources, trees
serve as shelter for butterflies. In winter,
Danaid butterflies gather in valleys, where
trees help block winds, so they can survive
through cold weather.
Butterflies and Humans
Although butterflies are usually just
appreciated for their beauty, they do
influence our daily lives! Butterflies help
to pollinate our crops; without them there
are many kinds of fruit that may not be
produced. Although butterfly caterpillars
that feed on our crops are pests.
Butterflies have a short lifespan and some
species are particularly vulnerable to
environmental threats. Therefore, butterflies
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are very important ecological indicators.
Caterpillars of different butterfly species
depend on different host plants. The
more butterfly species a place has, the
richer are its plant species. On the other
hand, butterfly species are very sensitive
to changes in their surroundings, so
higher numbers of species are usually
found in undeveloped areas. The types
and numbers of butterflies present in
a place can be an important factor for
deciding whether an area should be
safeguarded from development. When
their environment is under stress, they
are the first few to suffer and disappear.
The beautifully intricate patterns and
richly coloured wings of butterflies have
always been much admired. In many
countries, including China, butterflies are
good subjects for artist, indicating their
value in arts and literature.
Compared to many other wild animals,
butterflies are much easier to observe,
and can be excellent subjects for nature
education. Though it is their beauty,
perhaps that sparks people’s interest in
nature.
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