Tài liệu Rubber plantation performance in the Northeast and East of Thailand in relation to

Rubber plantation performance in

the Northeast and East of Thailand

in relation to environmental conditions

Laura Rantala

A thesis submitted for an M.Sc degree in Forest Ecology

Department of Forest Ecology/

Viikki Tropical Resources Institute (VITRI)

University of Helsinki

Finland

2006

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PREFACE

This M.Sc thesis was done under the framework of a project “Improving the productivity of

rubber smallholdings through rubber agroforestry systems in Indonesia and Thailand”. The

project is being financed by the Common Fund for Commodities (CFC). It is coordinated by

the World Agroforestry Centre (ICRAF), and research partners include the Indonesian Rubber

Research Institute, Kasetsart University (KU) and Prince of Songkhla University in Thailand,

and the University of Helsinki (UH). I received funding from the UH for travel expenses to

Thailand and for participation in a bilateral exchange programme between the universities of

Kasetsart and Helsinki.

My initial knowledge of rubber cultivation and the tropical environment was limited to say

the least. I am grateful to everyone involved in this work for the time they have generously

given for guiding me through the various stages of this work. Firstly I wish to express my

gratitude to my supervisor, Professor, Dr. Olavi Luukkanen (UH), Director of the Viikki

Tropical Resources Institute (VITRI), for making my participation in this project possible. I

am grateful for his supervision, valuable comments and interest in my work. During my field

work in Thailand, I received much academic as well as practical help from Associate

Professor, Dr. Suree Bhumibhamon and Dr. Damrong Pipatwattanakul (KU). Without their

support my work in Thailand would not have been possible. I am indebted to Dr. Vesa

Kaarakka (UH) for his help during various stages of my work and especially for thoughtful

comments on my manuscript.

In Thailand, I had the privilege to receive help from many people. I want to mention the staff

members of the Office of the Rubber Replanting Aid Fund in Bangkok, Nong Khai and

Buriram, who kindly assisted me in finding suitable sites for field study. I am grateful to Mr.

Arak Chantuma and Mrs. Pisamai Chantuma from Chachoengsao Rubber Research Centre for

providing me with the necessary facilities and assistance with the arrangements for my field

work. I want to thank Mr. and Mrs. Chorruk, Mr. and Mrs. Choochit and Mrs. Sompong

Puksa in Ban Kruen, Buriram, Mrs. Boonhouse Nanoy, Mr. Prasittiporn Sankarn and Mr. and

Mrs. Arlapol in Pak Khat, Nong Khai and Mrs. Pa Noom Thurtong in Lad Krating for

information, hospitality and for letting me conduct field inventories in their rubber

plantations. My field work would have not been possible without the help of Mr. Prin

Kalasee, Mr. Jakrapong Puakla, Ms. Waranuch Chansuri, Ms. Supanee Nakplang and Ms.

Pantaree Kongsat. I want to thank Mr. Chakrit Na Takuathung for helping me in finding

literature from Thailand once I had already returned to Finland. Finally I want to thank all

those who helped me and were very friendly to me making my short stay in KU and in

Thailand an unforgettable one.

I want to thank Professor, Dr. Jouko Laasasenaho and Timo Melkas for helping me with

calculating wood volume estimates for trees, and Riika Kilpikari for helping me with

statistics. Thanks are also due to Dr. Mohamed El Fadl for help in data search and comments

as well as to other VITRI staff and students for their comments. Last but not least I want to

thank my family and friends for their support.

Dublin, November 2006

Laura Rantala

This study was financed by the Common Fund for Commodities, an intergovernmental

financial institution established within the framework of the United Nations, headquartered in

Amsterdam, the Netherlands.

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CONTENTS

1. INTRODUCTION ...................................................................................................................... 5

1.1 Background of the study ....................................................................................................... 5

1.2 Scope and objective of the study......................................................................................... 10

2. LITERATURE REVIEW.......................................................................................................... 11

2.1 Botany and distribution of Hevea brasiliensis..................................................................... 11

2.1.1 Distribution of Hevea brasiliensis in Thailand............................................................. 12

2.2 Climatic requirements of the rubber tree ............................................................................. 14

2.3 Soil requirements of the rubber tree .................................................................................... 17

2.4 Rubber cultivation in Southeast Asia ................................................................................ 18

2.4.1 General characteristics................................................................................................. 18

2.4.2 Agroforestry practices ................................................................................................. 19

2.4.3 Environmental considerations...................................................................................... 21

2.5 Uses of Hevea brasiliensis.................................................................................................. 22

3. MATERIAL AND METHODS FOR FIELD STUDY............................................................... 23

3.1. Material ............................................................................................................................. 23

3.1.1 Field work and study areas .......................................................................................... 23

3.1.2 Plantation inventory .................................................................................................... 27

3.1.3 Interviews and field observations................................................................................. 28

3.1.4 Climatic conditions and soil types ............................................................................... 28

3.2 Methods ............................................................................................................................. 31

3.2.1 Estimation of wood volume and biomass..................................................................... 31

3.2.2 Mann-Whitney's U-test................................................................................................ 33

4. RESULTS................................................................................................................................. 34

4.1 Plantation performance ...................................................................................................... 34

4.1.1 Height and crown structure.......................................................................................... 34

4.1.2 Wood volume and biomass ......................................................................................... 37

4.2 Farming systems................................................................................................................. 44

4.2.1 General characteristics................................................................................................. 44

4.2.2 Agroforestry practices and land use history ................................................................. 45

5. DISCUSSION........................................................................................................................... 46

5.1 Variation in wood production potential between clones and study areas.............................. 46

5.2 Agroforestry practices in northeastern Thailand .................................................................. 49

5.3 Wood production potential in the Northeast and East compared to the South ...................... 50

5.4 Critical assessment of the study .......................................................................................... 54

5.4.1 Aims achieved............................................................................................................. 54

5.4.2 Limitations of the study............................................................................................... 55

6. CONCLUSIONS AND RECOMMENDATIONS ..................................................................... 57

REFERENCES ............................................................................................................................. 59

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LIST OF ABBREVIATIONS

BPM 2 4 Bank Pertanian Malaysia's rubber clone number 24

BB19 10-year old RRIM 600 stand in Buriram, 14°38'50 N, 103°12'72 E

BR10 16-year old RRIM 600 stand in Buriram, 14°38'56 N, 103°12'79 E

BR16 16-year old RRIM 600 stand in Buriram, 14°38'56 N, 103°12'79 E

BR03 3-year old RRIM 600 stand in Buriram, 14°38'65 N, 103°13'47 E

CB16 16-year old BPM 24 stand in Chachoengsao, 13°5' N, 101°5' E

CB08 8-year old BPM 24 stand in Chachoengsao, 13°5' N, 101°5' E

CR16 16-year old RRIM 600 stand in Chachoengsao, 13°5' N, 101°5' E

CR06 6-year old RRIM 600 stand in Chachoengsao, 13°5' N, 101°5' E

CR03 3-year old RRIM 600 stand in Chachoengsao, 13°59'41 N, 101°43'81 E

CRRC Chachoengsao Rubber Research Center (of the Rubber Research Institute of Thailand)

DBH Tree diameter at breast height (1.3 m)

DOA Department of Agriculture of Thailand

FAO Food and Agriculture Organization of the United Nations

GIS Geographic Information System

GPS Global Positioning System

LDD Land Development Department of Thailand

NB16 16-year old BPM 24 stand in Nong Khai, 18°37'11 N, 103°35'59 E

NB07 7-year old BPM 24 stand in Nong Khai, 18°36'09 N, 103°35'68 E

NR16 16-year old RRIM 600 stand in Nong Khai, 18°37'36 N, 103°35'60 E

NR08 8-year old RRIM 600 stand in Nong Khai, 18°36'09 N, 103°35'68 E

NR03 3-year old BPM 24 stand in Nong Khai, 18°37'07 N, 103°35'15 E

ORRA The Office of the Rubber Replanting Aid Fund

RFD Royal Forest Department of Thailand

RIS Rubber Information System developed by the Department of Agriculture of Thailand

RRIM 600 Rubber Research Institute Malaysia's rubber clone number 600

RRIT Rubber Research Institute of Thailand

TMD Thai Meteorological Department

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1. INTRODUCTION

1.1 Background of the study

The rubber tree, Hevea brasiliensis (Muell.) Arg., is a major crop for smallholders in Thailand

and an important commercial crop everywhere in Southeast Asia. It is grown for latex

production, while rubber wood is considered as a secondary product. Therefore rubber is

regarded as an agricultural crop. However, recent improvements in wood technology have led

to rubber tree becoming increasingly important as a source of wood products (Evans and

Turnbull 2004). Rubber wood has enjoyed an environmentally friendly reputation as a raw

material, because it is a by-product of latex production, and when grown in renewable

plantations, it can substitute timber from natural forests.

The natural range of Hevea, of the family Euphorbiaceae, covers the Amazon river basin and

parts of the nearby uplands. Within the genus, Hevea brasiliensis (also known as para rubber)

is one of the most widely distributed species. It grows in an area South of the Amazon river,

extending towards the west in Peru and the south to Bolivia and Brazil (Wycherley 1992).

The rubber tree has always been known for its latex, which was used by the ancient

civilizations of Central and South America. The commercial and large-scale exploitation of

the tree did not begin until in the last quarter of the 19th century. With the arrival of cars,

discovery of the pneumatic tyre and following increase in rubber prices, the produced amount

of plantation-originated rubber was soon larger than that of wild rubber. At the same time,

there were strong geo-political pressures to move the rubber production away from South

America (Jones and Allen 1992). While searching for a cash crop for its eastern colonies, the

British identified rubber as a potential crop for planting in Southeast Asia (Hong 1999).

Rubber was first introduced in Asia in 1876, when seeds were first shipped from the

Amazonas to the United Kingdom and further to Ceylon and planted there. In the following

year, rubber trees were planted in Singapore and Malaya (Hong 1999). Although rubber was

first an estate crop, local individual farmers soon adopted the crop and so they were drawn

into the world commercial economy (Courtenay 1979). Nowadays rubber is cultivated

worldwide in most parts of the lowland humid tropics, but the production is heavily

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concentrated into Asia, where over 90 % of the world’s natural rubber is being produced.

Rubber seeds were first brought to Thailand from Malaya in 1900 and planted in Trang

province in southern Thailand (RFD 2000). Estate agriculture was for political reasons

discouraged in Thailand, unlike in Malaya, in the beginning of the 20th century. Rubber

growing became important as a smallholder crop, when local farmers responded to the

improved rubber prices in mid-1920s and planted rubber in southern Thailand (Courtenay

1979). Favourable climatic conditions, free land areas and easy railway access enabled the

adoption of rubber growing in the South (Pendleton 1962). Small areas were planted

elsewhere, mainly in Chantaburi province, where rubber seeds and seedlings from Malaya

were first taken in 1908. Later the cultivation extended to some other eastern provinces (RFD

2000).

Peninsular Malaysia has been the world's most important rubber cultivation area, and the

present wealth of this area was largely based on production of natural rubber (Collins et al.

1991). In the year 2005, Indonesia, Thailand and Malaysia produced 33 %, 23 % and 13 % of

the world’s natural rubber, respectively (FAO 2006). Lately, the rubber plantation area has

been decreasing in Malaysia, but in Thailand the trend has been reverse and plantations have

started to spread to new areas in the East and Northeast of Thailand 1

. This area has been

referred to as non-traditional for rubber cultivation (Chantuma et al. 2005). Today Thailand

has the second largest area of rubber plantations in the world following Indonesia, is the

world's largest producer of natural rubber (FAO 2006) and also the world leader in rubber

wood production and export (LDD 2005a).

The rubber plantation area in Thailand is much larger than the area of forest plantations in the

country. According to FAO (2005), the total area of rubber plantations in Thailand was

1 680 000 ha in 2005. According to the statistics of the Rubber Research Institute of Thailand

(RRIT 1996 cited in RFD 2000), the rubber plantation area was larger already in the year

2000, when it was recorded as 1 959 000 ha. In comparison, the area of forest plantations in

Thailand in the year 2000 was 355 000 hectares. The area of natural forest in the same year

was 16 486 500 hectares (RFD 2001).

1 In this study, areas of Thailand are referred to as South, Central, East, Northeast and North. A map of Thailand

and names of provinces in these areas is in Appendix 1.

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Rubber has been referred to as a woody agricultural crop (FAO 2005) together with the oil

palm and coconut. In Thailand, the rubber plantation area is larger than the plantation area of

these two crops. In the year 2005, the plantation areas of rubber, oil palm and coconut were

1 680 000 ha, 315 000 ha and 343 000 ha, respectively (FAO 2006). The plantation areas of

both oil palm and rubber have been growing. Oil palm is cultivated in the South of Thailand,

which is also the traditional area for rubber cultivation. Competition for land area from other

crop species has been identified as one factor driving the establishment of rubber in new

areas.

In Thailand the smallholder rubber is intensively supported by the Royal Thai Government, in

forms of technology and production inputs such as seedlings, land preparation and fertilizer

(Joshi 2005). In recent years the Thai Government has been promoting rubber planting also in

new areas. In the year 2004, the goal was to extend the planted area, with a target of one

million rai (160 000 hectares) extension within two years from 2004 to 2006 (RRIT 2005).

The establishment of new rubber plantations has been promoted especially in the North and

Northeast of Thailand. The estimated extension of rubber cultivation area is 400 000 hectares

by the year 2010 (RRIT 2005).

In contrast to Malaysia, where rubber is mainly grown on large estates, in Thailand 90 % of

rubber is grown in family-owned smallholdings 2

less than eight hectares in size, the average

area of a plantation being only two hectares (Pratummintra 2005). Rubber yields per hectare

in Thailand are the highest of the three leading rubber-producing countries. This is due to

governmental support for smallholder rubber cultivation, and especially to the use of

improved planting material. Of the three leading rubber producers, the yield per hectare is

lowest in Indonesia, where rubber has traditionally been grown in “jungle rubber“

agroforestry systems. In these systems, the low yields have been reported to result from a low

level of maintenance and use of non-improved planting material (Wibawa et al. 2005).

Therefore, improving the productivity of rubber agroforestry has much potential especially in

2 In this study, the term smallholding is used to refer to family-owned small rubber plantations. The Department

of Agriculture (DOA) of Thailand has classified smallholdings, medium-sized holdings and estates as those

where rubber area is less than 8 hectares, 8-40 hectares and more than 40 hectares, respectively (Pratummintra

2005). According to Courtenay (1979), the smallholding is usually family-owned, managed by the family head

and worked by family labour. The plantation in turn is frequently owned by a company or a government

enterprise, and usually professionally managed (Courtenay 1979). In this study, the term plantation is, however,

used to refer to any organized planting regardless of size and management.