UNIVERSITI PUTRA MALAYSIA
EFFECTS OF LOGGING OPERATIONS ON SOIL PHYSICAL
PROPERTIES
AND SOIL EROSION IN A HILL DIPTEROCARP FOREST
OF PENINSULAR MALAYSIA
BAHARUDDIN KASRAN
FH 1992 3
EFFECTS OF LOGGING OPERATIONS ON
SOIL PHYSICAL PROPERTIES
AND SOIL EROSION IN A HILL DIPTEROCARP FOREST
OF PENINSULAR MALAYSIA
By
BAHARUDDIN
KASRAN
Thesis Submitted in Fulfillment of the Requirements
for the Degree of Master of Science in the
Faculty of Agriculture, Universiti
Pertanian Malaysia
December 1992
ACKNOWLEDGMENTS
I
would
l ike
to
express
my
gratitude t o my major superv�sor,
Mokhtaruddin
Universiti
bin
Abdul
Pertanian
most
sincere
and
deepest
Associate Professor Dr.
Hanan,
Faculty
Malaysia
for
his
of
Mohd
Ag r i c u lt u r e ,
helpful
advice,
encouragement and constructlve criticisms throughout the study.
Thanks
Professor
are
Dr.
Universiti
also
Nik
due
to
Huhamad
Pertanian
my
co-supe r v i s o r ,
A s s o c iate
of
Forestry,
Ha)ld,
Halaysla
for
Faculty
his
invaluable
comments ,
guidance and encouragement . Special thanks are due to Associate
Professor Dr.
Siti Zauyah Darus and her laboratory assistants
for their help in porosity analysis.
I would like to acknowledge the Forest Research Institute
Malaysia (FRIM)
for giving me the opportunity to undertake this
study. My appreciation
Leader
and
comments.
I
Mohd
to D r .
Zaki
Mohd
am indebted
to
Abdul Rahim Hj Nik,
Isa
my
at
FRIM,
cOlleagues
for
my project
his
Zulkifli
valuable
¥usop
and
Sai fuddin Sulaiman for their cooperation.
I
and
like to express my speclal thanks to the research staff
foresters
of
the
stesyen Kec il Jengka,
collection and
Hydrology
FRIM,
Section
and
field
staff
of
for their ass istance in field data
laboratory analyse s .
They are
Rajendran, Mohd
Sahat ,
Ahmad Shahar,
Ibrahim,
Hashim,
Mokhtar,
Ranjer Md Nor,
Ayoub, Alisbana, Mat Salleh, Mohd Adam and Ahmad Marhani .
Last but
wife,
Tuminah
not
patience
my deepest gratitude and
for her understanding,
and to my children,
and
least,
Baharina,
without
which
sacrifices
love to my
and patience;
Haizal and Hamiza for their love
this
completed.
iii
project
would
not
have
TABLE OF CONTENTS
Page
11
ACKNOWLEDGMENTS
LIST OF TABLES
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LIST OF FIGURES
LIST OF PLATES
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x
LIST OF ABBREVIATIONS
ABSTRACT
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xi
xii
xv
ABSTRAK
CHAPTER
I
II
INTRODUCTION
1
REVIEW O F LITERATURE
5
Logging System in Malaysia
5
Soil Erosion and Surface Runoff in a Tropical
Forest
6
Effects o f Logging on Surface Runoff and Soil
Loss
11
Effects o f Logging on Surface Runoff
Effects of Logglng on Soil Loss
Effects
of
Logglng
Properties
. . . . . . . .
. .
.
III
on
. . .
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METHODOLOGY
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11
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13
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16
Physical
Soil
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20
Experimental S ite
20
Location and Topography
20
Geology,
20
5011
and Vegetation
Climate
24
Establishment of Erosion Plots
28
Data Collection
31
Rainfall
31
Surface Runoff and Soil Loss Measurement ...
32
Inf iltration Rate
32
Soil Sampling and Analyses
34
Soil Sampling
34
Soil Physical Properties
35
Statistical Analyses
IV
36
38
RESULTS AND DISCUSS ION
38
Rainfall
Soil Physical Properties
.
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•
•
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•
•
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Soil Texture
Bulk Density
40
40
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41
Total Porosity
43
Organic Matter
51
Soil Water Characteristics
53
Infiltration Rate
56
Effects of logging on Surface Runoff and Soil
Loss
59
Surface Runoff
59
Soil Loss
68
v
v
SUMMARY AND CONCLUSION
summary
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75
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•
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.. .. .. .
75
Conclusion
79
REFERENCES CITED
81
VITA
94
vi
LIST OF TABLES
Page
Table
1
2
Soil Erosion and
Runoff from Various Land
Uses in Sarawak, Malaysia
So�l Strength,
Infiltration
Bulk Density,
Rate
Air Space
of Surface So il
and
Classified b y Types o f Disturbance
.
3
of
P hy si ca l
Characteristics
Experimental Basin
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of the
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5
Jengka Experimental
Annual Rainfall for
Basin, March 1987 to February 1989
9
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18
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23
Study Area
.
8
.
25
Climatic Conditions
7
.
Jengka
.
4
6
10
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•
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38
Textural Compositl.on
of Undisturbed Area,
Skid Trails and Logging Roads of Jengka
Experimental Basin
41
M.ean
Soil Bulk Density of Undisturbed
Skid Trails and Logging Roads o f
Area,
Jengka Experimental Basin
42
Mean Total
Porosl.ty of Undisturbed Area,
Skid Trails and Logging Roads of Jengka
Experimental Basin
44
Mean Values
of Total Number of
Pores of
Skid Trails and Logging
..........
Roads of Jengka Experimental Basin
Undisturbed Area,
10
11
Total Porosity and Number of Pores in Each
Plot at Different
Slopes of
Undisturbed
Area, Skid Trails and Logging Roads
Organic
Matter
Content
of
Undisturbed
Area,
Skid Trails and Logging Roads of
Jengka Experimental Basin
.
12
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Mean of Soil Mo�sture Characteristics of
Three Different Slopes ( 1 0 , 20 and 30%) of
Disturbed
and
Undisturbed
Areas
at
Dif ferent Pressures
vii
46
52
.
.
.
.
53
54
13
14
15
16
Mean Available Water Capacity on Each Plot
of Undisturbed and Disturbed S it e s of
Jengka Experimental Basin
55
I n f iltration Rates on
Undisturbed and Disturbed
Experimental Basin
57
Each P l o t
of
Sites o f Jengka
Annual
Rainf a l l ,
Surface
Runoff
and
from
Coefficient
Rainfall-Runoff
Undisturbed and Disturbed Sites of Jengka
Experimental Basin
..........................
.
Runoff
Surface
Annual
Rainfall
and
Characteristics of
Undist urbed Forest
in
Jengka Experimental Basin .
. .
.
.
17
I.
19
20
22
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.
and
surface
Skid Trails in
Rainfall
Annual
Characteristics of
Experimental Basin
.
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63
Runoff
Jengka
64
and
Surface
Runoff
Annual
Rainfall
in Jengka
Characteristics of Logging Roads
Experimental Basin
65
Annual Soil Loss from Control and Treatment
Plots of Jengka Experimental Basin
6.
Annual Soil Loss
from undisturbed Forest
on Different Slopes of Jengka Experimental
Basin
.
21
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60
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Annual
Soil Loss
from the
on Different Slopes of Jengka
Basin
.
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Trails
Skid
Experimental
Annual Soil Loss
from the
Logging Roads
on Different Slopes of Jengka Experimental
. . . . . . . . . . .... . . . . . . . . . . . . . . . . . . . . . . . . . .
Basin
viii
72
73
74
LIST OF FIGURES
Page
Figure
1
Location of Study Site
2
Layout of Jengka Experimental Basin
3
Mean
Monthly Rainfall
D istribution of
Jengka Experimental
Basin Based on Seven
Years Data ( 1 981 - 1987)
. . ... . . .. . ... . . . . . . .
4
5
6
7
8
9
10
11
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•
•
•
Erosion Plots and
Jengka Experimental
Rainfall
Portable
I n f i ltration Rate
I nstrument
Layout
Soil Pore Size
Trail
Monthly
.
21
.
26
27
to
Measure
33
D istribution
for
the
1987
39
the
48
for the
Skid
49
Distribution
for
the
50
Rainfall-Runoff
of the
.
30
Simulator
Distribution
Soil
Size
Pore
Logging Road
.
at
Basin
Monthly
Rain fall Distribution During
Study Period from March
Two-Year
to February 1989
Pore
Size
Soil
Undisturbed Forest
•
22
Mean Monthly of Some Climatic Parameters
of Jengka Experimental Basin Based on Seven
Years Data (1981-198 7 )
Variation
12
.
Study
coefficient
Plots
Monthly Soil Loss from Undisturbed Forest,
Skid Trail and Logging Road
of Jengka
Experimental Basin
ix
66
71
LIST OF PLATES
Page
Plate
1
Extraction o f Log
on the Skid Trail
Using
Crawler
7
2
Winched Lorry
3
Erosion Plot
on the Loggi ng
•
Regeneration
Logging Road
one Year After
or
Tractor
7
"San-Tai-Wong"
of Pioneer
K
Road
spec ie s o n
Logging
29
the
62
LIST OF ABBREVIATIONS
FAO
Food and Agriculture Organization
IAHS
International Association of
Science
IUFRO
International Union
Organization
m.a. s . l .
Meter above sea level
UNESCO
United Nations Educational,
Cultural Organization
USDA
United States Department of Agriculture
xi
of
Hydrological
Forestry Research
Scientific
and
Abstract
Pertanian
of thesis subm1.tted to the
Malaysia
in
fulfillment
of
Senate of Universiti
requirements for the
the
degree of Maater of Science.
EFFECXS OF LOGGING OPERATIONS ON SOIL PHYSICAL PROPERTIES
AND SOIL E ROSI ON IN A HILL DIPTEROCARP FOREST
OF PENINSULAR MALAYSIA
By
KASRAN
BAHARUODIN
December
Chairman:
Associate Prof.
Faculty :
Agriculture
The
effects
properti es
mainly
trail
on
and
and
109g1-ng
of
soil
severely
road.
Soil
logging
samples
and
road
amount
the
plots
of
upper
und1.sturbed
area
phys ical
forest
pa rt icu lar ly
were
on
occurred
the
were
of
skid
es tabli she d
surface runoff
layer
Hanan
Abdul
soil
on
log g e d- over
ErOS10n
the
from
1n
s011,
disturbed
logging
Mohd Mokhtaruddin
operations
erOS10n
these areas to quantify
loss.
Dr.
1992
the
and
skid
in
soil
trail,
for
soi l
properties
w e re
analyzed
physical properties.
Significant
observed
as
a
increased by
logging road,
chan ges
result
of
1n
S011
physical
10gg1.ng operat ions.
The
bulk
density
32 percent on the sk1d trail and 42 percent on the
and
the
total
porosity
'H
reduced by
62
and
69
percent,
respectively.
total
porosity
About
82
but
percent
Logg1ng operat1ons
also
of
changed
the
tota l
the
consisted of elongated pores,
and 1 1 . 4 percent f issures pores.
porosity
of 62
consisted
transmission and 4 . 9
road,
the figures
Thus the infiltration rate lS
more
elongated
pores
that
play
pores.
undisturbed
area
pores
the total
6.2
pores,
pores
2.6
of
transmission
e l ongat ed
and
soil than in the skid trail and
on
percent
percent f1ssures
6.4
reduced the
On the skid trail,
percent
are 35,
onl y
and Slze
shape
poros1ty
18.2
not
percent
and on the logging
percent,
respectively.
r a p1d in undisturbed forest
road because it is the
10gg10g
important
an
role
water
in
transmission. The higher the 1nf1ltrat1on rate the lower is the
surface runo f f .
The
annual
surface
trail and undisturbed
runoff
forest were
the total r a inf all ,
respect1vely.
are 1 3 , 3 4 1 ,
and 450
10,070
major proportion of the
originated
from
erosion occurred
less
severe
the
sediment yield
skid
second
trails and
the
Y1eld
1n logged-over
and
year
year.
sk�d
after
On
the
was
factors 1nfluencing
10gglng
roads
X III
skid
Th er efore a
respectively.
from the und�sturbed areas
Slope is one of
the
the
f1rst
road,
corresponding soil losses
The
roads
logging
1 4 . 5 and 2.3 percent of
20.3,
sed�ment
the
the
kg/ha/y,
l099�n9
du r1n g
dur ing
from
dur1ng
the
forest
tra�lB.
logging
other
Severe
and
hand
was
the
insignificant.
soil
erosion
fi rs t
year
from
after
The amount of SOll loss in the logged-over
logging operations.
forest can be reduced l.f
gradl ent
the
of the skid
trails and
logging roads does not exceed 20 percent.
Erosion
erosion
control
from
the
measures
10gglng
focused
should
roads
and
skid
on
controlling
trails.
Control
measures such as con str uct lon of cross drains on logging roads
and
skid trails
must
logging
operations.
logging
ro ads
condition
improve
of
the
and
be
done
Another
skl.d
option
t ra l ls
soil such as by
infiltratlon
lmmedl.ate1y
lS
fo r
to
erosion
improve
SUb-solllng.
characterl.stics
enhancing regeneration of vegetatl.on.
nv
completion
upon
cont r o l
the
the
on
surface
Such practice
of
of
soils
will
and
Abstrak
Pertanian
tesis
Malaysia
ke·pada
dikemukakan
bagi
memenuhi
universiti
Senat
keperluan
untuk
memperolehi
Ijazah Master Sains.
KESAK-KESAN OPERASl PEMBALAKAN KE ATAS SlFAT-SIFAT
FIZlKAL DAN HAKISAN TANAH 01 HUTAH D1PTEROKAP
8UK1T 01 seMENANJUNG MALAYSIA
01eh
BAHARUDDIN KASRAN
Desember 1992
Pengerusi
Prof. Madya Dr. Mokhtaruddin Abdul Manan
Fakulti
Pertanian
Kesan-kesan operasi pembalakan ke atas sifat-sifat fizikal
tanah dan hakisan di hutan yang telah dibalak sering berlaku di
tanah
yang menga1ami
tarik
dan ja1an ba1ak.
ini
bagi
menentukan
kerosakan
yang
Petak-pet.ak
jum1ah
air
teruk,
terutama
hakisan
larian
dibina
permukaan
terhakis. Contoh tanah di lap�san atas jalan tarik,
dan
kawasan
tidak
diganggu
telah
dianalisa
di
di
jalan
kawasan
dan
tanah
jalan balak
untuk
menentukan
sifat-sifat fizikal tanah.
Operasi
atas
pembalakan
sifat-sifat
peratus
di
menyebabkan
fizikal tanah.
jalan
tarik
dan
berlakunya
Ketumpatan
42
peratus
perubahan
pukal
di
bertambah
jalan
ke
32
balak.
Sebaliknya jumlah keliangan masing-masing berkurangan kepada 62
,v
dan
69
peratus
pembalakan
bukan
di
jalan "tar1k
sahaja
jumlah
keliangan
di
daripada liang memanjang,
peratus
11.4
liang
jalan
mengurangkan
juga mengubah bentuk dan saiz
dari
dan
keliangan.
kawasan
18.2
rekahan.
jumlah
01
Jalan
82
diganggu
penghantaran
dan
peratus
4.9
balak angka-angka tersebut ialah 35,
itu
proses
penyusupan
mudah
bel"laku
tarik
liang
peratus
terdiri
pula,
62
d1
6 . 2 peratus
rekahan.
hutan
dan
peratu$
Oi
jalan
6 . 4 dan 2.6 peratus.
berbanding di jalan tarik dan jalan balak.
liang memanjang memainkan peranan
bahkan
liang penghantaran
jumlah keliangan terdiri daripada liang memanjang,
liang
Operasi
keliangan
Kira-kira
tidak
peratus
balak.
tidak
Oleh
diganggu
Ini disebabkan oleh
penting bagi pergerakan air
dalam tanah. Semakin tinggi kadar penyusupan semakin rendah air
larian permukaan.
Air larian permukaan tahunan di
dan
hutan
peratus
tanah
tidak
dari
diganggu
jumlah
hujan"
masing-masing
jalan
masing-masing
In1
20.3,
bersamaan
sebanyak
balak,
13, 3 4 1 ,
jalan
14.5
dengan
10,070
tarik
dan
2.3
kehilangan
450
dan
kg/ha/tahun. Oleh itu sebahagian besar hasil kelodak dari hutan
telah dibalak beraeal dari jalan balak dan jalan tarik.
yang teruk terjadi
berkurangan
pada
pada tahun
tahun
pertama
ber ikutnya.
selepas
Sementara
pembalakan
kawasan
diganggu menyumbangkan sedik1t sahaja hasil kelodak.
xvi
Hakisan
dan
tidak
Kecerunan
mempengaruhi
satu
hakisan
tanah
tahun
pertama
terutama pada
terhakis
merupakan
dari
kawasan
ini
daripada
dari
faktor-faktor
yang
ja
' lan
se lepas
boleh
pembalakan.
dikurangkan
Jumlah
jika
tanah
kecerunan
jalan tarik dan jalan balak tidak melebihi 20 peratus.
Langkah-langkah
mengawal
langkah
balak
hakisan
tersebut
dan
jalan
di
mencegah
jalan
seperti
tarik
kawasan
ini
ialah
balak
pembinaan
ini
akan
diutamakan
jalan
parit
tarik.
melintang
serta-merta
Satu lagi cara bagi
memperbaiki
mengemburkan permukaan tanah di
Amalan
dan
harus
harus dilaksanakan
operaei pembalakan tama t .
di
hakisan
meningkatkan
Langkahdi
jalan
setelah
mengawal hakisan
keadaan
tanah
seperti
kawasan-kawasan tereeb u t .
Kadar
mempercepatkan pertumbuhan tumbuh-tumbuhan.
XVlJ.
untuk
penyusupan
dan
CHAPTER
I
INTRODUCTION
During the past two decades more than 1 . 5 million hectares
of
lowland tropical
converted
rubbe r ,
to
oil
reduction
agricultural
palm
of
constituted
forests
and
land
75
Peninsular Malaysia have been
land
cocoa.
forested
about
in
mainly
for
This has
in
the
percent
of
the
planting
resulted
country.
the
in
In
total
a
massive
1955
land
forest
area
Peninsular Malaysia. This was further reduced to 5 5 percent
1970,
50 percent in 1980 ( Chong,
(Malaysia,
of
in
in
1 9 8 5 ) and 47 . 7 percent in 1990
Ministry of primary Industries,
1991) .
Most
of the
forested land in Malaysia today are confined to hilly areas and
steep terrains and the lowland dipterocarp forests have almost
been totally replaced by agricultural crops.
Logging activities in the steepland areas have created a
number
most
of
serious environmental
obvious
areas,
downstream
increased
are
soil
reservoirs.
those
such
pertaining
as
erosion,
the
to
deterioration
river
I n Malaysia,
and ecological
the
in
sedimentation
effects of
problems.
hydrology
water
and
timber
The
of
quality,
silting
of
harvesting on
soil erosion and sedimentation have been reported by a number
of investigators including Burgess ( 19 7 1 ) , Baillie ( 1972 ) , Liew
(1974) ,
Jones ( 197 6 ) ,
Salleh et al . ,
1
(1981a,
1981b ) ,
Lai and
2
Shams uddin
( 1 985 ) ,
Lai
and
Rentap
(1986 )
and
Baharuddin
( 1988a ) .
Most
of
watersheds.
The
determining
watershed.
these
studies
common
approach
sediment
content
( sheet,
rill
erosion.
The
logging
activities
of
to
on
experimental
estimate
stream
erosion
water
from
by
the
which is attributed mainly to surface
and
general
gully ) ,
sediments
still
stream
conclusion
of
contributed
a
sediments in the stream water.
of
is
based
It provides the general idea o f the treatment effect
on sediment production,
erosion
were
remains
bank
these
and
studies
significant
Nevertheless,
unknown.
It
streambed
is
that
amount
of
the exact source
is
imperative
to
indicate the exact location and sediment regime i n the area so
that systemat ic erosion control measures could be implemented
to minimize sediment content in the streams.
I n addition to sedimentation, forest harvesting operations
are
definitely
physical
Logging
one
properties
road
of
and
the
factors
aesthetic
constr u c t i o n ,
transportation
during
values
usage
logging
that
of
changed
of
heavy
operations
tend
the
the
soil
landscape.
maChinery
to
and
mOdify
the
physical properties of the upper layer of forest soil which may
significantly affect regeneration growth. The impact of logging
operations on soil physical properties in temperate region
well
documented
( Froehlich
study has not been reported,
1972 ) .
However ,
in
Malaysia,
except by Kamaruzaman ( 1987 ) .
is
such
The
3
alteration of soil physical properties due to timber harvesting
is
c l os e l y
a s s o c iated
with
soil
loss
of
the
area.
This
relationship characteristics and the soil loss variation should
be studied in order to gain a better understanding of the soil
erosion problem.
This thesis reports
a study of
the
relationship between
timber harvesting, soil erosion and Boil physical properties in
a
logged-over
objective
forest
in
P e n i n s u l a r Ma lays i a .
determine the
is to
amount
of
The
surface
general
runoff
and
soil loss and to assess the changes in soil physical properties
resulting from construction of logging road and skid trails in
logged-over
forest
of
Peninsular
Malaysi a .
The
spec i f i c
objectives are to:
1.
quantify
loss
the
from
amount
logging
of
roads,
surface
runoff
skid
and
trails
soil
and
undisturbed forest, and
2.
describe some selected soil
density,
porosity,
soil
properties
organic
such
matter,
as bulk
soil
water
characteristics and infiltration rate on the logging
road,
skid trail and undisturbed forest.
The study was conducted in a logged-over forest at
Tekam
Forest Reserve, Pahang, Peninsular Malaysia. Nine erosion plots
were established on three dif ferent sites,
forest,
namely undisturbed
skid trails and logging roads. At each site, plots were
4
established on three d i fferent slope categories
percent ) .
operation
The
was
study
commenced
completed
and
six
continued
months
for
a
( 10 ,
20 and 30
after
period
years, that i s , from March 1987 to February 1989.
logging
of
two
CHAPTER II
REVIEW OF LITERATURE
Logging system in Malaysia
Selective logging method was introduced
forest management system since 1948 .
in Malaysia as
a
It was then known as the
Halayan Uni form System (MUS) (Wyatt-Smith,
1 9 6 3 ) . A new system
known as the Selective Management System (SHS) was implemented
in 1970 to replace HUS because the
HUS system was found to be
unsuitable
hill
1986) .
to be practiced
This new system
objectives
of
sustainability
an
and
in the
forest
areas
( Thang,
was designed to optimize the management
economic
minimum
and
efficient
forest
harvesting,
development
cost.
forest
In
this
system, minimum cutting limits are 45 and 50 cm diameter breast
height
for
the
non-dipterocarp
and
dipterocarp
species.
respectivel y .
The logging system which has been developed in the forests
of Halaysia are completely mechanized and
(FAO,
1970,
operations
1973; E l l i s ,
include
tree
and log transportat ion.
and
forest
debris
1 9 7 6 ; Jones,
felling,
requires low capital
1976).
The basic logging
construction
of
During road construction,
are pushed
aside to
ensure
forest
road
the topsoil
firm
and
level
footing for the skidding operat ion. The activities during this
operation and the usage o f heavy earth-moving equipment
5
such
6
as
tractors
cause severe soil degradat ion.
and skidders
In
log transportation, the crawler tractor is used for skidding or
hauling the
logs
from the
felling
site
to
temporary
landing
( P l ate 1 ) . The logs that are skidded are usually largei
100
em in diameter at breast height,
heavy
equipment
are
used.
to
cut into logs of about 5
to 7 m long or sometimes at tree length.
only
50
Under such practice,
The main
vehicle
tranporting
logs to the logyard is a winch lorry locally known as " San-TaiWong"
( Plate 2 ) .
These
skidding and transportation activities
can cause serious degradation of soil physical properties both
during the dry and wet seasons. 50il degradation and compaction
resulting from logging will certainly induce surface runoff and
erosion.
soil Erosion and Surface Runoff in a
Tropical Forest
In
forest
the
temperate
is minimal
for the tropical
even
under
that
forest
amount
dipterocarp forest
1 , 5 29
3
m /ha/y
however much
erosion
1975) .
in
(Leigh,
1987 ) .
of
is
not true
can
be
detected
1979;
Putjaroon and Pongboon
( 19 8 7 )
Saho1nakron
and 664 kg/ha/y,
undisturbed
Fearnside,
runoff
1978;
in
This
forest because soil erosion
natural
the
surface
(Megahan and King,
Putj aroon and Pongboon,
found
zone ,
and
soil
loss
in
a
dry
Province of Thailand were
respectively .
lower when compared to that
of
The
values
abandoned
are
fields
7
Plate
1.
Extraction of Log Using Crawler
Tractor on the
Plate
2.
Skid Trail.
Winched Lorry or
"San-Tai-Wong".