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 most sincere and deepest

gratitude t o my major superv�sor, Associate Professor Dr. Mohd

Mokhtaruddin bin Abdul Hanan, Faculty o f Agr i c u lt u r e ,

Universiti Pertanian Malaysia f o r h i s h e l p f u l advice,

encouragement and constructlve criticisms throughout the study.

Thanks are a l s o due to my co-supervisor , A s s o c iate

Professor D r . Nik Huhamad Ha)ld, Faculty of Forestry,

Universiti Pertanian Halaysla for 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 to Dr. Abdul Rahim Hj Nik, my project

Leader and Mohd Zaki Mohd Isa at FRIM, for his valuable

comments. I am indebted to my cOlleagues Zulkifli ¥usop and

Saifuddin Sulaiman for their cooperation.

I like to express my speclal thanks to the research staff

and foresters o f the Hydrology Section and field staff of

stesyen Kec il Jengka, FRIM, for their assistance in field data

collection and 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 not least, my deepest gratitude and love to my

wife, Tuminah for her understanding, sacrifices and patience;

and to my children, Baharina, Haizal and Hamiza for their love

and patience without which t h i s project would not have

completed.

iii

TABLE OF CONTENTS Page

ACKNOWLEDGMENTS 11

LIST OF TABLES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vii

LIST OF FIGURES . . . . . . . . . . . . . . . . : . . . . . . . . . . . . . . . . . . . . . . . . . ix

LIST OF PLATES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . x

LIST OF ABBREVIATIONS . . . . . . . • • • . . . . . . . . . . . . • • . . . . . . . . . . . . x i

ABSTRACT . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xii

ABSTRAK xv

CHAPTER

I INTRODUCTION 1

II REVIEW OF 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 of Logging on Surface Runoff . . . . . . 11

Effects of Logglng on Soil Loss . . . . . . . . . . . 13

Effects of Logglng on Soil Physical Properties . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

I I I METHODOLOGY 20

Experimental Site 20

Location and Topography 20

Geology, 5011 and Vegetation 20

IV

Climate 24

Establishment of Erosion Plots 28

Data Collection 31

Rainfall 31

Surface Runoff and Soil Loss Measurement ... 32

Infiltration Rate 32

Soil Sampling and Analyses 34

Soil Sampling 34

Soil Physical Properties 3 5

Statistical Analyses 36

RESULTS AND DISCUSSION 38

Rainfall 38

Soil Physical Properties . . . . . . . . • • . . . . . . . . • • . . . 40

Soil Texture 40

Bulk Density . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41

Total Porosity 43

Organic Matter 5 1

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 7 5

summary . . . . . . . . . . . . . . . . . . . . . • . . . . . . • • • . • . . . . . . . 7 5

Conclusion

REFERENCES CITED

VITA

vi

79

81

94

LIST OF TABLES

Table

1 Soil Erosion and Runoff from Various Land

2

3

Uses in Sarawak, Malaysia

Bulk Density, Rate and Classified

So�l Strength, Infiltration Air Space of Surface Soil

Physica l

b y Types of Disturbance . . . . . . . . . . .

Characteristics of Jengka

Page

10

18

Experimental Basin . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 3

4

5

Climatic Conditions of the Study Area

Annual Basin,

Rainfall for March 1987 to

Jengka Experimental February 1989 . . . . . . . . . • .

6 Textural Compositl.on of Undisturbed Area, Skid Trails and Logging Roads of Jengka

7

8

9

Experimental Basin

M.ean Area, Jengka

Soil Bulk Density of Undisturbed

Skid Trails and Logging Roads of

Mean Skid

Experimental Basin

Total Trails

Porosl.ty of

and Logging Experimental Basin

Undisturbed Area, Roads of Jengka

Mean Values of Total Number of Pores of Undisturbed Area, Skid Trails and Logging Roads of Jengka Experimental Basin . . . . . . . . . . .

10 Total Porosity and Number of Pores in Each

Plot at Different Slopes of Undisturbed

11

Area, Skid Trails and Logging Roads

Organic Matter Content of Undisturbed Area, Skid Trails and Logging Roads of Jengka Experimental Basin . . . . . . . . . . . . . . . . . . . .

12 Mean of Soil Mo�sture Characteristics of Three Different Slopes (10, 20 and 30%) of Disturbed and Undisturbed Areas at Different Pressures

vii

2 5

38

41

42

44

46

52

53

54

13 Mean Available Water Capacity on Each Plot of Undisturbed and Disturbed S ites of Jengka Experimental Basin

14 I n f iltration Rates on Each Plot o f Undisturbed and Disturbed Sites o f Jengka

15

16

Experimental Basin

Annual Rainfall, Surface Runoff and Rainfall-Runoff Coefficient from Undisturbed and Disturbed Sites of Jengka Experimental Basin . . . . . . . . . . . . . . . . . . . . . . . . . . .

Annual Rainfall and Surface Runoff Characteristics of Undisturbed Forest in

55

57

60

Jengka Experimental Basin . . . . . . . . . . . . . . . . . . . 63

17

I.

Annual Rainfall and surface Runoff Characteristics of Skid Trails in Jengka Experimental Basin

Annual Rainfall Characteristics of Experimental Basin

and Logging

Surface Runoff Roads in Jengka

64

65

19 Annual Soil Loss from Control and Treatment

20

21

22

Plots of Jengka Experimental Basin 6.

Annual Soil Loss from undisturbed Forest on Different Slopes of Jengka Experimental Basin . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72

Annual Soil Loss from the on Different Slopes of Jengka Basin

Annual Soil Loss from the

Skid Trails Experimental

Logging Roads on Different Slopes of Jengka Experimental

73

Basin . . . . . . . . . . .... . . . . . . . . . . . . . . . . . . . . . . . . . . 74

viii

Figure

1

2

3

4

5

6

7

8

LIST OF FIGURES

Location of Study Site . . . . . . . . . . . . . . . . • • • • . . .

Layout of Jengka Experimental Basin

Mean Monthly Rainfall D istribution of Jengka Experimental Basin Based on Seven Years Data ( 1981 - 1987) . . . . . . . . . . . . . . . . . . . . .

Mean Monthly of Some of Jengka Experimental Years Data (1981-198 7 )

Climatic Parameters Basin Based on Seven

Erosion Plots and Jengka Experimental

I nstrument Layout at Basin

Portable Rainfall Simulator to Measure Infiltration Rate

Monthly Rainfall Two-Year Study to February 1989

Soil Pore Size Undisturbed Forest

Distribution During Period from March

Distribution for

the 1987

the

9 Soil Pore Size Distribution for the Skid

10

11

12

Trail

Soil Pore Logging Road

Size Distribution for the

Monthly Rainfall-Runoff

Variation of the Study Plots

coefficient

Monthly Soil Skid Trail

Loss from Undisturbed Forest, and Logging Road of Jengka

Experimental Basin

ix

Page

21

22

26

2 7

30

33

39

48

49

50

66

71

Plate

1

2

3

•

LIST OF PLATES

Extraction of Log

on the Skid Trail Using Crawler Tractor

Winched Lorry or "San-Tai-Wong"

Erosion Plot on the Logging Road

Regeneration Logging Road

of one

Pioneer spec ies on Year After Logging

K

the

Page

7

7

29

62

FAO

IAHS

IUFRO

m . a . s . l .

UNESCO

USDA

LIST OF ABBREVIATIONS

Food and Agriculture Organization

International Association of Hydrological Science

International Union of Forestry Research Organization

Meter above sea level

United Nations Educational, Scientific and Cultural Organization

United States Department of Agriculture

xi

Abstract of thesis subm1.tted to the Senate of Universiti

Pertanian Malaysia in fulfillment of the requirements for the

degree of Maater of Science.

EFFECXS OF LOGGING OPERATIONS ON SOIL PHYSICAL PROPERTIES

AND SOIL EROSI ON IN A HILL DIPTEROCARP FOREST

Chairman:

Faculty :

OF PENINSULAR MALAYSIA

By

BAHARUODIN KASRAN

December 1992

Associate Prof. Dr. Mohd Mokhtaruddin Abdul Hanan

Agriculture

The effects of 109g1-ng operations on soil phys ical

properties and soil erOS10n 1n logged-over forest occurred

mainly on severely disturbed s011, particu larly on the skid

trail and logging road. ErOS10n plots were es tablished i n

these areas to quantify the amount of surface runoff and soil

loss. Soil samples from the upper layer of the skid trail,

logging road and und1.sturbed area were analyzed for soi l

physical properties.

Significant chan ges 1n S011 physical properties w ere

observed as a result of 10gg1.ng operations. The bulk density

increased by 32 percent on the sk1d trail and 42 percent on the

logging road, and the total porosity reduced by 62 and 69

'H

percent, respectively. Logg1ng operat1ons not onl y reduced the

total porosity but also changed the shape and Slze of pores.

About 82 percent of the total poros1ty on undisturbed area

consisted of elongated pores, 1 8 . 2 percent transmission pores

and 1 1 . 4 percent f issures pores. On the skid trail, the total

porosity consisted of 62 percent el ongated pores, 6.2 percent

transmission and 4 . 9 percent f1ssures pores and on the logging

road, the figures are 35, 6.4 and 2.6 percent, respectively.

Thus the infiltration rate lS more ra p1d in undisturbed forest

soil than in the skid trail and 10gg10g road because it is the

elongated pores that play an important r o l e in water

transmission. The higher the 1nf1ltrat1on rate the lower is the

surface runo f f .

The annual surface runoff from the logging road, skid

trail and undisturbed forest were 2 0 . 3 , 1 4 . 5 and 2.3 percent of

the total rainf all , respect1vely. The corresponding soil losses

are 1 3 , 3 4 1 , 10,070 and 450 kg/ha/y, respectively. Ther efore a

major proportion of the sed�ment Y1eld 1n logged-over forest

originated from the l099�n9 roads and sk�d tra�lB. Severe

erosion occurred du r1n g the f1rst year after logging and was

less severe dur ing the second year. On the other hand the

sediment yield from the und�sturbed areas was insignificant.

Slope is one of the factors 1nfluencing soil erosion from

the skid trails and 10gglng roads dur1ng the firs t year after

X III

logging operations. The amount of SOll loss in the logged-over

forest can be reduced l.f the grad l ent of the skid trails and

logging roads does not exceed 20 percent.

Erosion control measures should focused on controlling

erosion from the 10gglng roads and skid trails. Control

measures such as construct lon of cross drains on logging roads

and skid trails must be done lmmedl.ate1y upon completion of

logging operations. Another option for erosion control on

logging roads and skl.d tralls lS to improve the surface

condition of soil such as by SUb-solllng. Such practice will

improve the infiltratlon characterl.stics of the soils and

enhancing regeneration of vegetatl.on.

nv

Abstrak tesis dikemukakan

Pertanian Malaysia bagi memenuhi

Ijazah Master Sains.

ke·pada

keperluan

Senat

untuk

universiti

memperolehi

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 kerosakan yang teruk, terutama di jalan

tarik dan ja1an ba1ak. Petak-pet.ak hakisan dibina di kawasan

ini bagi menentukan jum1ah air larian permukaan dan tanah

terhakis. Contoh tanah di lap�san atas jalan tarik, jalan balak

dan kawasan tidak diganggu telah dianalisa untuk menentukan

sifat-sifat fizikal tanah.

Operasi pembalakan menyebabkan berlakunya perubahan ke

at as sifat-sifat fizikal tanah. Ketumpatan pukal bertambah 32

peratus di jalan tarik dan 42 peratus di jalan balak.

Sebaliknya jumlah keliangan masing-masing berkurangan kepada 62

,v

dan 69 peratus di jalan "tar1k dan jalan balak. Operasi

pembalakan bukan sahaja mengurangkan jumlah keliangan bahkan

juga mengubah bentuk dan saiz keliangan. Kira-kira 82 peratus

dari jumlah keliangan di kawasan tidak diganggu terdiri

daripada liang memanjang, 18.2 peratus liang penghantaran dan

11.4 peratus liang rekahan. 01 Jalan tarik pula, 62 peratu$

jumlah keliangan terdiri daripada liang memanjang, 6 . 2 peratus

liang penghantaran dan 4.9 peratus liang rekahan. Oi jalan

balak angka-angka tersebut ialah 35, 6 . 4 dan 2.6 peratus. Oleh

itu proses penyusupan mudah bel"laku d1 hutan tidak diganggu

berbanding di jalan tarik dan jalan balak. Ini disebabkan oleh

liang memanjang memainkan peranan penting bagi pergerakan air

dalam tanah. Semakin tinggi kadar penyusupan semakin rendah air

larian permukaan.

Air larian permukaan tahunan di jalan balak, jalan tarik

dan hutan tidak diganggu masing-masing 2 0 . 3 , 14.5 dan 2 . 3

peratus dari jumlah hujan" In1 bersamaan dengan kehilangan

tanah masing-masing sebanyak 13, 3 4 1 , 10,070 dan 450

kg/ha/tahun. Oleh itu sebahagian besar hasil kelodak dari hutan

telah dibalak beraeal dari jalan balak dan jalan tarik. Hakisan

yang teruk terjadi pada tahun pertama selepas pembalakan dan

berkurangan pada tahun ber ikutnya. Sementara kawasan tidak

diganggu menyumbangkan sedik1t sahaja hasil kelodak.

xvi

Kecerunan merupakan satu daripada faktor-faktor yang

mempengaruhi hakisan tanah dari j'alan tarik dan jalan balak

terutama pada tahun pertama se lepas pembalakan. Jumlah tanah

terhakis dari kawasan ini boleh dikurangkan jika kecerunan

jalan tarik dan jalan balak tidak melebihi 20 peratus.

Langkah-langkah mencegah hakisan harus diutamakan untuk

mengawal hakisan di jalan balak dan jalan tarik. Langkah-

langkah tersebut seperti pembinaan parit melintang di jalan

balak dan jalan tarik harus dilaksanakan serta-merta setelah

operaei pembalakan tamat. Satu lagi cara bagi mengawal hakisan

di kawasan ini ialah memperbaiki keadaan tanah seperti

mengemburkan permukaan tanah di kawasan-kawasan tereebut.

Amalan ini akan meningkatkan Kadar penyusupan dan

mempercepatkan pertumbuhan tumbuh-tumbuhan.

XVlJ.

CHAPTER I

INTRODUCTION

During the past two decades more than 1 . 5 million hectares

of lowland tropical forests in Peninsular Malaysia have been

converted to agricultural land mainly for the planting of

rubber, oil palm and cocoa. This has resulted in a massive

reduction of forested land in the country. I n 1955 forest

constituted about 7 5 percent of the total land area in

Peninsular Malaysia. This was further reduced to 55 percent in

1970, 50 percent in 1980 ( Chong, 1985) and 47 . 7 percent in 1990

(Malaysia, 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 of serious environmental and ecological problems. The

most obvious are those pertaining t o the hydrology of

downstream areas, such as deterioration in water quality,

increased soil erosion, river sedimentation and silting of

reservoirs. In Malaysia, the effects of timber harvesting on

soil erosion and sedimentation have been reported by a number

of investigators including Burgess ( 1971 ) , Baillie ( 1972 ) , Liew

(1974) , Jones ( 1976 ) , Salleh et al . , (1981a, 1981b ) , Lai and

1

2

Shams uddin ( 1 985 ) , Lai and Rentap (1986 ) and Baharuddin

( 1988a ) .

Most of these studies were based on experimental

watersheds. The common approach is to estimate erosion by

determining sediment content of stream water from the

watershed. It provides the general idea of the treatment effect

on sediment production, which is attributed mainly to surface

erosion ( sheet, rill and gully) , stream bank and streambed

erosion. The general conclusion of these studies is that

logging activities contributed a significant amount of

sediments in the stream water. Nevertheless, the exact source

o f sediments s t i l l remains unknown. I t is imperative to

indicate the exact location and sediment regime in the area so

that systematic erosion control measures could be implemented

to minimize sediment content in the streams.

I n addition to sedimentation, forest harvesting operations

are definitely one of the factors that changed the soil

physical properties and aesthetic values of the landscape.

Logging road construction, usage of heavy maChinery and

transportation during logging operations tend to 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 is

well documented ( Froehlich 1972 ) . However , in Malaysia, such

study has not been reported, except by Kamaruzaman ( 1987 ) . The

3

alteration of soil physical properties due to timber harvesting

i s c l os e l y associated with s o i l l o s s o f the a r e a . 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 forest in Peninsular Ma lays i a . The general

objective is to determine the amount of surface 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 the amount of

loss from logging roads,

undisturbed forest, and

surface runoff and soil

skid t r a i l s and

2. describe some selected soil properties such as bulk

density, porosity, soil organic matter, 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 different sites, namely undisturbed

forest, skid trails and logging roads. At each site, plots were

4

established on three different slope categories ( 10 , 20 and 30

percent ) . The study commenced six months after logging

operation was completed and continued for a period of two

years, that is, from March 1987 to February 1989.

CHAPTER II

REVIEW OF LITERATURE

Logging system in Malaysia

Selective logging method was introduced in Malaysia as a

forest management system since 1948 . It was then known as the

Halayan Uniform System (MUS) (Wyatt-Smith, 1963). 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 to be practiced in the hill forest areas ( Thang,

1986) . This new system was designed to optimize the management

objectives of an economic and efficient harvesting, forest

sustainability and minimum forest development cost. In this

system, minimum cutting limits are 45 and 50 cm diameter breast

height for the non-dipterocarp

respectively.

and dipterocarp species.

The logging system which has been developed in the forests

of Halaysia are completely mechanized and requires low capital

(FAO, 1970, 1973; Ellis, 1976; Jones, 1976). The basic logging

operations include tree felling, construction of forest road

and log transportation. During road construction, the topsoil

and forest debris are pushed aside to ensure firm and level

footing for the skidding operation. The activities during this

operation and the usage of heavy earth-moving equipment such

5

6

as tractors and skidders cause severe soil degradation. In

log transportation, the crawler tractor is used for skidding or

hauling the logs from the felling site to temporary landing

(Plate 1 ) . The logs that are skidded are usually largei 50 to

100 em in diameter at breast height, cut into logs of about 5

to 7 m long or sometimes at tree length. Under such practice,

only heavy equipment are used. The main vehicle tranporting

logs to the logyard is a winch lorry locally known as " San-Tai-

Wong" ( 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 the temperate zone , surface erosion in undisturbed

forest is minimal (Megahan and King, 1975) . This is not true

for the tropical forest because soil erosion can be detected

even under natural forest (Leigh, 1 9 7 8 ; Fearnside, 1979;

Putj aroon and Pongboon, 1987 ) . Putjaroon and Pongboon ( 19 8 7 )

found that the amount o f runoff and soil loss i n a dry

dipterocarp forest in Saho1nakron Province of Thailand were

1 , 529 m3/ha/y and 664 kg/ha/y, respectively . The values are

however much lower when compared to that of abandoned fields

Plate 1. Extraction of Log Using Crawler

Tractor on the Skid Trail.

Plate 2. Winched Lorry or "San-Tai-Wong".

7