Transcript Woodland Ecosystem - Tai Po Kau Nature Reserve Field Study

WOODLAND ECOSYSTEM TAI PO KAU NATURE
RESERVE FIELD STUDY
4C Cheung Tsz Ching (11)
4C Li Huan Huan (22)
4C Tai Mung Wan (27)
HISTORY AND INTRODUCTION OF
TAI PO KAU NATURE RESERVE

Tai Po Kau Nature Reserve, located in the Tai Po Kau
Special Area. It has been well known among all the people
who are interested in nature.
It was originally called
the Tai Po Kau
Plantation, there are
440 hectares of forest
on the steep catchment
area of the stream near
the car park area at the
entry of the country
park. The height
extends from 50 metres
to 650 metres at the top
of Grassy hill ( Tso
Shan ) .
WEATHER CONDITION ON 6/3/2010
The temperature range is about 20-22 ℃. Sometimes,
there were sunshine but with a cloudy sky.
Relationship between different tree
layers and relative humidity
Water, or moisture, is the most important factor in a
habitat. It carries nutrient to the vegetation that favors
the process of photosynthesis.
Due to much rainfall, vegetation amount in Tai Po
Kau is very much. It shows that the weather is wet
enough for vegetation growth. As the tall trees need
much water that works as the raw material for
photosynthesis, the relative humidity will be higher.
Besides, tall trees (Canopy layer and emergent layer)
block lots of sunlight, reduce level of evaporation, so,
the surrounding air contains relatively more moisture,
and relative humidity is high.
Short trees (ground layer
and shrub layer) also
need water to grow, most
of the sunlight absorbs
most of the sunlight, and
so, short trees and the
surrounding air may be
wet as the
evapotranspiration rate is
low. The relative
humidity may be higher
than the tall trees layer.
THE AMOUNT OF VEGETATION
COVER AFFECTING STEMFLOW AND
THE QUALITY OF THE SOIL

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The branches of the trees intercept the large amount
of rainfall, most of the water runs along the branches
and reaches the ground.
Rainfall affect soil formation so much. The rapid
of stemflow will cause leaching. Heavy rainfall causes
a downward movement of water and the soluble
materials in the soil, the soluble materials may be
slash away by the rainwater. There is a strong
downward movement of bases and silica that is
decilication. Without silicate colloids, the soil is firm
and porous rather than sticky and plastic,
transmitting water easily, the horizons are not
distinctive although lower layers tend to be darker in
color due to the accumulation of bases and colloids.

In conclusion, stemflow may destroy the structure of
the soil and the nutrient of the soil may be loss by the
slash of the rainwater and leaching.
SPECIES FOUND IN TAI PO KAU
NATURE RESERVE

The dominant tree was
Chinese Red Pine ( Pinus
massoniana ) and
because of that the area
has come to be known
locally as Tsung Tsai
Yuen, meaning Pine
Garden. More recently,
small areas of Camphor
Tree, China Fir, Acacia
and Paper-bark Tree
have been planted

There are also many interesting native species, such
as the Litsea, Giant Bean and Sweet Gum. As you
walk along the quiet paths you find stretches of
ground carpeted with large, brown leaves. These are
from the tree called Castanopsis fissa, a good timber
tree formerly much used by the Chinese in making
agricultural implements such as the primitive wooden
plough. Of all the special areas in Hong Kong, this
one is probably the richest in variety of native species
of trees.
ADVANTAGES FOR PLANTS TO BE
EPIPHYTES

Epiphytes is a kind of herbs that grow in crevices of
the larger trees, without roots, epiphytes cannot
uptake nutrient from the soil but by growing in
crevices of the larger trees in a network-like shape,
letters trapped by the epiphytes then become the
nutrient for them
Epiphytes absorb more
sunlight and rainwater than
other short plants because it
crevices the larger trees so
they can get to a higher place
which can receive more
sunlight and rainfall.
DIFFERENCE BETWEEN
EPIPHYTES AND PARASITIES

Parasities is a kind of
climbers which also
grow in crevices of the
larger trees. But they
are also nourished by
host tress, some have
aerial roots in which
falling leaves may be
trapped and then
provide the plants with
nutrients.


Parasities take
nutrient from the host
trees, sometimes, or
eventually, the host trees
may die as the parasities
uptake most of their
nutrient.
Epiphytes just grow in
crevice of the larger trees
but do not take any
nutrient from the trees.
So, they are not harmful
for the trees and will not
affect the lives of the
trees.
THE DIFFERENCES BETWEEN THE
CROWNS OF EMERGENT LAYER AND
THOSE OF THE LOWER LAYER

As this is a Sub Tropical Rain Forest, it made up of a range of
codominant species. As they want to fight for the sunlight, the
main canopy is the emergent layer. They are the main canopy,
most of them have umbrella-shaped crowns in order to increase the
surface area to obtain maximum sunlight.
Therefore they can intercept most
of the rainfall, and obtain most of
the insolation. And the drip tips of
the leaves allow the moisture from
the frequent rains to be shed to the
lower layer. And there is some
buttress root or stilt root, it provide
added stability to very tall trees.
The appearance of buttress root
And the continuous canopy. Most of them are 15 to 30m and
with long tapering crowns. About half are usually sapling of
the larger trees. From a continuous canopy which absorbs
more than 70% of the ligh and intercept 80% of rainfall. They
shade the underlying species, but they protect the soil from
erosion.
-The lower layer of the canopy.

The shorter trees under the following canopy only about 10m.
It have crowns that are narrow in proportion to sunlight, an
adaptation that enables them to take maximum advantages of
such light as penetrates the canopy. In the TRF there are not
many shorter trees. As the result of the competition for
sunlight, it is discontinuous and becoming dense only where
there are breaks in the canopy. They included herbs, such as
ferns. A considerable proportion of bare ground and little
undergrowth because there are less than 5% of insolation to
forest floor.
The lowest
layer grow in
the breaks in
canopy. They
are usually
small in size.
THE FUNCTIONS PERFORMED BY
BUTTRESS ROOT

According to the photo we
can see that the spur-like
swellings at the base of the
tree trunk are known as
buttresses. The buttress
provide support of the tree
and it increase the stability
of big trees. It can grow
much future away from the
main stem. In a nut shell,
this is a structural
adaptation of the trees.
THE WAYS OF THE PLANTS CLIMB

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The climbing plants from by the wind from tree to
tree from the forest floor, beginning their growth in
shaded conditions and forming branches, when they
reach the upper layers and obtain sufficient light.
They growth along the stem of the host tree and then
climb up to the top in order to obtain sufficient
sunlight for their growth. They can climb up to the
upper part or even the top of the host tree.
THE IMPORTANCE OF LITTER TO
SOIL QUALITY

In the photo there is a lot of l litter on the floor it act as a
important role in the soil quality. Because it provide a lot of
nutrient to the soil. The rapid decay of the leaf litter and
recycling of nutrient. They are produce by coniferous
evergreen trees and healthland.
After they decompose
they become humus
finally, and humus is the
major source of nutrients
and it combines with
clays to form clay-humus
complex which is very
important for a fertile soil
as it provides it with a
high water-and nutrientholding capacity.


Also humus act as a cement, binding he soil particles
together and thus reduces the risk of erosion by
improving cohesion
The humus is decomposed by bacteria, earthworms
and fungi. The present of humus tends to give the soil
a brown or black colour.
Present of Fungi and the dark brown soil
SOME PHOTO