EFFECTS OF FERTILISER APPLICATION ON SOIL PROPERTIES OF SMALLHOLDER PEPPER

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FARM AT DIFFERENT AGE STAND IN BAU.

Esther Sheren Anak Joseph

Master of Environmental Science (Sustainable Land Use and Water Resource Management)

2015

Effects of Fertiliser Application on Soil Properties of Smallholder Pepper Farm at

Different Age Stand in Bau.

ESTHER SHEREN ANAK JOSEPH

Supervisor

Dr. Mohd Effendi Wasli

A Dissertation Paper Submitted in Partial Fulfillment to the Requirement for Master

Degree in Environmental Science

Master in Environmental Science

(Sustainable Land Use and Natural Resource Management)

2015

Faculty of Resource Science and Technology

UNIVERSITI MALAYSIA SARAWAK

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ACKNOWLEDGEMENTS

Foremost, I would like to thank God for giving me the strength and patient upon this

final semester project completion progress. Next, I would like to give my appreciation to my

supervisor, Dr. Mohd Effendi Wasli for giving me some useful advice and guidance for the

completion of this report. My grateful thought for my family especially my father and

classmates for landing their hand during the field work. I would also like to thank Mr. Mugu

for assisted me in the laboratory. Special thanks to all the farmers that involved during the

interview session and for allowing me to collect samples from their farm. Last but not least for

all my friends for giving me moral support and prayers.

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TABLE OF CONTENT

Page

Acknowledgement i

Table of Content ii

List of Abbreviations v

List of Figures and Tables vi

Abstract viii

CHAPTER 1: INTRODUCTION

1.1 Background of Pepper

1.2 Statement of the Problem

1.3 Research Objectives

CHAPTER 2: LITERATURE REVIEW

2.1 Study Area and Land Use Practices

2.2 Black Pepper

2.2.1 Agronomic Requirements for Pepper Cultivation

2.2.2 Maintenance of Pepper Farm

2.3 Challenge Faced by Pepper Farmers in Sarawak

2.4 Soil Type in Malaysia

2.5 Fertilizer Runoff and Effect Toward Soil

2.6 Soil Contamination from Fertilizer

2.7 Soil Structure and Cultivation

2.8 Comparison Between Organic and Non-organic Fertilizer

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CHAPTER 3: METHODOLOGY

3.1 Study Area

3.2 Methods for Soil Sampling and Interviews

3.2.1 Soil Sampling

a) Composite Soil Sampling

b) Soil Sampling for Undisturbed Sample

3.2.2 Samples Preparation

3.2.3 Methods for Field Soil Analysis

a) Soil Colour

b) Soil Texture

3.2.4 Methods for Soil Laboratory Analysis

a) Soil Bulk Density and Porosity

b) Soil Chemical Analysis

3.3 Statistical Analysis

3.4 Interview

CHAPTER 4: RESULTS AND DISCUSSIONS

4.1 Agronomic Practices of Pepper Cultivation in the Studied Areas

4.2 Field Assessment on the Soil in the Studied Area

4.3 Soil Properties in Pepper Farm of Different Age Stand

a) Bulk Density

b) Soil Porosity

c) Soil pH

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d) Soil Electrical Conductivity (EC)

e) Soil Organic Matter (SOM)

f) Available Phosphorus (P)

4.4 Interview Session

CHAPTER 5: CONCLUSION AND RECOMMENDATION

5.1 Conclusion

5.2 Recommendation

REFERENCE

APPENDIX 1 Samples of Interview Questions

APPENDIX 2 Soil Properties

APPENDIX 3 SOM Calculation

APPENDIX 4 Available Phosphorus Data

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LIST OF ABBREVIATION

ARC - Agriculture Research Centre

DOA - Department of Agriculture

EC - Electrical Conductivity

Kpg. - Kampung

MPB - Malaysian Pepper Board

SOM - Soil Organic Matter

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LIST OF FIGURES AND TABLES

Figures Page

Figure 2.1: ‘Kuching’ variety pepper which is commonly plant in Bau 4

Figure 2.2: Green pepper of ‘Kuching’ variety 4

Figure 2.3: Example of pesticide used by the farmer on pepper field 7

Figure 3.1: Locations of Kpg. Stenggang and Kpg. Opar 14

Figure 3.2: Locations of Kpg. Stass and Kpg. Duyoh 15

Figure 3.3: Whole map of Bau district 15

Figure 3.4: Sampling points for each area 17

Figure 3.5: Fertilized soil 18

Figure 3.6: Non-fertilized soil 18

Figure 3.7: Soil sampling for undisturbed area 19

Figure 3.8: Soil colour template 20

Figure 3.9: Chart of procedures for Feel Method 22

Figure 3.10: Bulk density preparation 23

Figure 4.1: Average bulk densities for 0-5cm depth 28

Figure 4.2: Average percentage of porosity for each category 29

Figure 4.3: Average percentage of pH for fertilized area and 30

non-fertilized area

Figure 4.4: Dolomite used to liming of soil 32

Figure 4.5: Average percentage of pH for non-fertilized area 32

Figure 4.6: Average percentage of SOM for each category 34

Figure 4.7: Artificial shades of young vines with eggplant in 36

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between the vines

Figure 4.8: Pepper vine age more than ten years old 36

Figure 4.9: Available phosphorus (P) 37

Tables Page

Table 1 GPS coordination for the four villages 16

Table 2 Categories of soil samples 17

Table 3 Field assessment on soil properties in the studied area 26

Table 4 General relationship of soil bulk density to root growth based 27

on soil texture.

Table 5 Standard percentage of soil porosity 29

Table 6 Agronomic practices by the farmer based on interview 38

viii

Effects of Fertilizer Application on Soil Properties of Smallholder Pepper Farm at

Different Age Stand in Bau

Esther Sheren anak Joseph

Master of Environmental Science

Faculty of Science and Technology

Universiti Malaysia Sarawak

ABSTRACT

The application of fertilizer is depending on the requirement of the plant. As for pepper, fertilizer application is

according to the maturity of the pepper vine. The difference of fertilizer for the young vine and mature vine is the

ratio of N (Nitrogen), P (Phosphorus) and K (Potassium) content in the fertilizer. For younger vine which is

below than three years old, the ration of NPK fertilizer is 12:12:17 as only focus on plant growth, and 15:15:15

for pepper vine more than three years old as focus more toward producing yield. The fertilizer applied also

affected by the agronomic practices by the smallholder pepper farm. Agronomic practices are the method farmers

incorporate into their pepper farm management systems to manage crops and improve soil quality. Therefore, the

objective of this study is to determine the effects of fertilizer application on the soil properties in smallholder

pepper farm in relation to different age stand. In this study, samples collected from fertilized and non-fertilized

areas from each farm. This is to determine the fertilizer application is directly or indirectly affecting the soil

properties and determine the significant differences between different age stand. Among the properties measured

were pH and EC, soil organic matter (SOM) content, and available phosphorus (P). The result shows that among

the different age stand, there is no significant differences between the properties except for available P from the

fertilized area in the older pepper farm which is more than ten years old. The significant impact to that can be

seen in the reducing amount of yield produced.

Keyword: pepper, fertiliser, age stand, agronomic practice, smallholder

ABSTRAK

Penggunaan baja adalah bergantung kepada keperluan tumbuhan. Bagi lada, penggunaan baja adalah mengikut

kematangan pokok lada. Perbezaan baja untuk pokok lada yang muda dan pokok lada yang matang adalah

nisbah kandungan N (Nitrogen), P (Phosphorus) dan K (Kalium) dalam baja. Untuk pokok lada muda iaitu di

bawah daripada tiga tahun, nisbah baja NPK adalah 12:12:17 kerana hanya memberi tumpuan kepada

tumbesaran pokok, dan nisbah 15:15:15 untuk pokok lada yang berusia lebih dari tiga tahun kerana lebih

tertumpu kepada pengeluaran hasil. Baja yang digunakan juga dipengaruhi oleh amalan agronomi oleh

peladang kecil. Amalan agronomi adalah kaedah petani dalam sistem pengurusan ladang lada mereka untuk

menambahkan tanaman dan meningkatkan kualiti tanah. Oleh itu, objektif kajian ini adalah untuk menentukan

kesan penggunaan baja kepada tanah di ladang pekebun kecil lada berhubung dengan pendirian umur yang

berbeza. Dalam kajian ini, sampel yang diambil adalah daripada kawasan disenyawakan dan tidak

disenyawakan dari setiap ladang. Ini adalah untuk menentukan penggunaan baja yang secara langsung atau

tidak langsung memberi kesan kepada sifat tanah dan menentukan perbezaan yang ketara di antara pendirian

umur yang berbeza. Antara ciri-ciri yang diukur ialah pH dan EC, kandungan bahan organik tanah (SOM), dan

fosforus (P). Hasil kajian menunjukkan bahawa antara pendirian umur yang berbeza, tidak ada perbezaan yang

ketara diantara cirri-ciri yang diukur, kecuali terdapat dalam P dari kawasan yang disenyawakan di ladang lada

yang berusia lebih daripada sepuluh tahun. Kesan ketara yang boleh dilihat adalah dari hasil yang berkurangan

oleh pokok lada yang berusia lebih dari sepuluh tahun.

Kata kunci: lada, baja, pendirian umur, amalan agronomi, pekebun kecil

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Chapter 1

INTRODUCTION

1.1 Background of Pepper

Piper nigrum L or known as pepper is one of the most common spices used in food flavouring

worldwide especially in India and Southeast Asia. It is also known as the “King of Spices” and

it is the most important spice traded internationally. Pepper is a tropical climbing vine, and

this species is native to south-western India (Lau et al., 2012). The peppercorn can be

separated in three colours, which are green pepper, white pepper, and lastly is the most

common black pepper.

Malaysia ranked fifth in pepper producer in the world with production of 25,672 metric

tonnes per year. In Malaysia, the main pepper producer is Sarawak which reports for more

than 95% of the total Malaysian production. Other remaining producers are from Johor and

Sabah (IPC, 2014). In Sarawak, the most widely grown cultivar or variety is „Kuching‟

because of it has vigorous growth and high yielding.

Pepper is one of the most important crops in Sarawak‟s economy. Pepper was first

cultivated in Sarawak back in 1856 but was extensively planting in 1900s (DOA, 2014). Until

today, pepper is still cultivated as important cash crops which support the livelihood of rural

dwellers in Sarawak. Few areas focus more on pepper cultivation in Sarawak are Kuching,

Samarahan, Sri Aman, Betong and Sarikei Divisions.

Pepper is planted as perennial cash crop by the local farmers in Sarawak, other than

rubber. One of the reason pepper and other cash crops are handled by the smallholder farmer

in Sarawak is because of the support by the government‟s agricultural policies. Cultivation of

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cash crop increased due to the need of cash income in a monetary economy and thus shifting

cultivation for rice production had changed into diverse cash cropping (Tanaka et al., 2009).

From the 1960s to 1970s, the agriculture sector started to expand because of the abundance of

land, cheap labour and policies expansion by the government to develop paddy and export

crops such as rubber, pepper, oil palm and cocoa. Agriculture was the driver for the Malaysian

economy back then where it provides opportunities for employment, reduced rural poverty and

earned foreign exchange for the country (Indrani, 2001).

1.2 Statement of the Problem

Pepper is sensitive to weather condition and moisture stress, and due to high absorption of soil

moisture by the plant, therefore irrigation is important to maintain the water content in soil.

Protecting pepper vine against the various pests and diseases often by chemical means, and it

causes side effects toward the soil properties as well. Any fertiliser residue are seep into the

soil and changes the soil quality such as nitrogen exported from agricultural systems will

contribute to eutrophication and the development of algal blooms (Barlow et al., 2007) as the

off-side effects and increase in soil acidification (Bünemann et al., 2006). Soil acidification

caused by high fertilizer level contributes to plant disease such as chlorosis on the pepper

leaves (Yap, 2012). Plant health is reduced due to restricted root growth and reduces seedling

growth in the acidic soil (Schumann, 2002 and Zu et al., 2014).

At different age of pepper, the amount of fertiliser input also at different ratios.

Especially for compound fertiliser, pepper aged three years and above at least received

50:50:150g/vine/year because at this age is when pepper started produce fruits and ready to be

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harvested (ICAR, 2014). For pepper farm aged three years and below, the younger plant

received different ratios of fertilizer as only focus on vegetative growth. For some farmers, the

application of fertilizer amount are different and only according to availability of fertilizer

stocks Thus the differences of soil properties on different aged of pepper farm can be seen

through the agronomic practices of the farmers. The used of organic fertilizer and non-organic

fertilizer depending on the farmer‟s choice. Both types of fertilizer contain different chemical

content, thus they affects the soil properties in different ways.

By using laboratory analysis, the result can be used to show the dynamic of fertiliser

on each category and what effluent the method of fertiliser application. Through interview, we

can know more about the pattern of agronomy practices by the farmers.

1.3 Research Objectives

The main objective of this study is to determine the effects of fertilizer application on the soil

properties in smallholder pepper farm in relation to different age stand. Fertilized area and

non-fertilized areas are selected to determine the fertilizer application is directly or indirectly

affecting the soil properties. Significant differences are also determined through the soil

properties among the different age stand of pepper farm.

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Chapter 2

LITERATURE REVIEW

2.1 Study area and land use practices

The study area comprise of Bidayuh community the villages are mostly can be found near the

riverbanks, foothills and inland areas. Most of the villagers do practices agriculture and cash

crops on their land. Their lands are mostly heredity from their ancestors. Since their ancestors

planting crops for their own consumption, the older generations still continue the traditions of

planting fruits and vegetables on their land. Nowadays most of the farmers started shifting

cultivation for cash crops such as rubber, pepper, pineapple and recently the oil palm. Native

farmers, mostly Ibans and Bidayuhs are now make up about 87% of pepper farmers in

Sarawak, largely through assistance of planting schemes implemented by the DOA since 1972

(State Farmers Organisation Sarawak, 2014).

Figure 2.1 „Kuching‟ variety pepper which is Figure 2.2Green pepper of „Kuching‟ variety

commonly plant in Bau

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2.2 Black pepper

The black pepper is native to Indian and widely exported throughout the world. The scientific

name of the black pepper is Piper nigrum L. which is considered the king of spices and it the

most widely used due to its pungent principle piperine. This unique characteristic of the black

pepper is attributed for the sharp and stinging qualities of the spice. Other than adding as food

spices, black pepper also added as food preservative and as essential component in traditional

medicines in India and China (Srinivasan, 2009).

Black pepper has a unique active ingredient of the black pepper compound, piperine,

has many physiological effects such as enhance digestive capacity of the pancreas, and

significantly reduces gastrointestinal food transit time. Modern medical researcher had interest

on this black pepper compound and it has documented for many medicinal purposes

(Srinivasan, 2009).

Pepper is mostly sold in large scale such as metric tonnes. But for smallholder, it is

usually sold in kilogram (kg). In 2013 the pepper price was around RM15, 000 per metric

tonnes, and one hectare (ha) can produce about RM60,000 per metric tonne. Black pepper and

white pepper are sold at different price. Black pepper can reach up to RM15 to RM16 per kg

and white pepper is sold at RM25 to RM26 per kg. In 2014, the average yearly price of pepper

is RM20, 952 per tonnes for black pepper and RM30, 742 per tonnes for white pepper (MPB,

2014).

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2.2.1 Agronomic requirements for pepper cultivation

Pepper usually grows on slightly sloppy sites which is ideal for drainage. Pepper is sensitive to

moisture stress, due to high evapo-transpiration coefficient of the crops and it will drain the

soil moisture. The pepper vine best thrives in the tropics, which have hot and moist climate.

The climate which receive rainfall annually of about 100 inches and at elevations from 1500

feet mean sea level. It tolerates a minimum of 10ºC and a maximum of 40°C. It can grow on

flat or gently sloping land which rich with humus and good drainage and light shade (IPC,

2014). Areas with prolong drought should be avoided or otherwise the soil moisture should be

maintained by proper supplementary irrigation. The most important element in pepper

cultivation is fertile soil. Pepper can grow on clay loams, red loams and sandy loams, but the

plant grows best in well drained loamy soils which rich in organic matter and other plant

nutrient. The plants will face difficulties growing on clay soil because it restricts root growth

and create moisture stress during short dry spells. Poor drain soils may leads to many soil-

borne diseases (DEA, 2010). The soil pH is acid or slightly acid with value between 5.5 and

6.5.

Pepper plants have high demand for nutrients. The application of fertiliser can be

chemical or organic. Organic fertiliser refers to manures which can be obtained from animal

dung, compost or even green leaves to apply on each vine. Application of chemical fertiliser is

essential to sustain high yield. Liming material (dolomite) is sometimes applied to pepper vine

to improve the calcium and magnesium nutrition to raise the soil pH. It is important to provide

sufficient major plant nutrients such as nitrogen, phosphorus and potassium for the young

vine. Mature vine only require substantial nitrogen and potassium (State Farmers Organisation

Sarawak, 2014).

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(a) (b)

Figure 2.3 Example of pesticide used by the farmer on pepper field

Figure 2.3 (a) and (b) shows one of the example of pesticide that is used by the farmer.

Pepper often affected by a host of pests and diseases. The most serious pests that damage the

vine and flower spikes are pepper weevil (Lophobaris piperis) and tingid bugs (Dicronocoris

hewetii). For diseases, fungi are the most prevalent cause of diseases in pepper. The most

common diseases that usually attack the plant are foot rot (Phytophthora capsici), black berry

(Colletotrichum capsici, C. piperis and C. gloeosporioides), pink disease (Corticium

salmonicolor), velvet blight (Septobasidium sp.), white root (Rigidoporus lignosus) and slow

decline or yellowing of the leaves (due to combined infestation by nematode, Radopholus

similis and Fusarium solani).

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2.2.2 Maintenance of pepper farm

To minimize damages to pepper vines during harvest season, good maintenance is required

before and after harvesting and also to maintain the quality and quantity of pepper berries.

Mounding, liming before planting, pruning, weeds control, fertilizing, and pest and disease

control are included in the farm maintenance (Rosli et al., 2013).

During the beginning of pepper plantation, there are three stages of shoot type, the first

stage is primary climbing shoot with long internodes having adventitious roots at nodes which

cling to the supports/standards, the second stage is runner shoots which originate from the

base of the vine and creep on the ground, have long internodes which strike roots at each node,

and the third stage is fruit bearing lateral shoots. The vines are planted at spacing of 3m x 3m

which can fill up to 1110 standards per hectare.

For starter, the young vine should be protected from direct hot sun by providing

artificial shade, and the practice is repeated until the second year. After the third or fourth

year, the shading will lop carefully to regulate height of the standards and to shade vine

optimally. During flowering and fruiting, excessive shading will encourage pest infestations.

For the fertiliser dosage, a recommended rate of NPK at 50: 50: 150 g/vine/year for

three years and above is essential because nutrients are required for flowering and at yield

production. The first year only receive one-third of this dosage and two-third for the second

year (ICAR, 2014).

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2.3 Challenge faced by pepper farmers in Sarawak

Pepper farmers in Sarawak are mostly the rural poor smallholders. They cultivated pepper as

one of the main cash crop and as their sole income generator. Pepper has higher market access

than other agriculture products, thus it makes pepper as their important source of income. But

through some times in the future, pepper farmers in Sarawak will face challenges in pepper

cultivation. The main producers of pepper are mainly from the interior lands. As stated by

Wong (2008), the farmers facing competitive issues in employment opportunities from those

with education and rural-urban migration which have reduced the interest in pepper

production. Furthermore, introduction of new technologies to increase crops yield of pepper

farms without basic infrastructure and facilities had been inhibited by the scattered pepper

farms on hilly terrain. Other than that, the cost of maintenance of pepper farm is also high.

Another challenge faced by pepper farmers is the attack from various diseases such as

Phytophthora foot rot, black berry velvet blight and wrinkled leaf diseases and damaging pests

like tingid bug, pepper weevil and nematodes. Labour shortages, lack of land suitability and

intense competition in the global market from trade liberalization also contribute to the

challenges to farmers.

2.4 Soil type in Malaysia

Agriculture practices had cause soil contamination in various ways. One of the causes is from

fertiliser runoff. In Malaysia, the types of soil are mainly influenced by the parent materials

and topography. The soils in the interior upland areas are mainly from granite, shale,

sandstone and limestone. The orders of soil that can be found in Malaysia are Inceptisols,

Ultisols and Oxisols which these types of soil are highly weathered acid soils with low fertility

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status. Malaysia receives heavy rainfall annually, and with that, low cation exchange capacity

of the soils lead to high infiltration rates in these soils (Khanif and Salmijah, 1996).

2.5 Fertilizer runoff and effect toward soil

Fertiliser input increase crop yields but it also causing damage to environment. In one long-

term investigation about 55 years old that was done by William et al. (2013) in one agriculture

farm in Sweden, usage of phosphate rock by farmers had declined over the last decades in

which it may lead to depletion of soil nutrient that weaken future crop production. The

investigation is to determine the effects of eight different inorganic fertiliser regimes at four

sites: no phosphorous and potassium fertilisation or annual replacement of harvested

phosphorous and potassium, combined with 0, 50, 100, or 150kg nitrogen ha-1

yr-1

on a range

of soil properties and microbial community composition. They also investigated the effect of

microbial activities that arose from differences in underlying soil properties which results from

application of fertilisation.

The investigation found out that reduced application of fertiliser directly reduced organic

carbon and nitrogen, and plant-available phosphorous on the topsoil. Also, the microbial

community composition does not affected by the different fertiliser regimes. Inorganic

fertilisation practices for a long-term have less significant impact on the microbial community

composition, but they are prone to influence the organic matter inputs and underlying soil

properties. However, the microbial biomass can be increased relative to fungal biomass and

increase soil organic carbon due to nitrogen fertilisation (William et al., 2013).

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2.6 Soil contamination from fertilizer

Several problems can arise from high rate of fertiliser addition to the soil. Fertiliser runoff can

lead to soil contamination and thus the risks include groundwater contamination. Human

health is at risk when they expose to drinking of contaminated groundwater. Contaminants can

be in varies form, for example pesticides, fertilizer, heavy metals and several organic

compounds.

Black pepper requires high nutrient, therefore fertiliser use is important to sustain growth

and high yield. Applying organic fertiliser alone is not enough to achieve high yield

production of crops. Thus, integrated fertiliser is very important to increase the crops yield but

it also lead to increase of soil acidification and drop of pH around the pepper root system.

Lower pH level of soil may lead to nutrient deficiency, and leaching of nutrients after

displacement from soil particles (Ann, 2012).

2.7 Soil structure and cultivation

Soil is a component for water transportation and storage of organic matter, thus making it vital

for providing all the nutrients to the crops and maintaining growth. If the soil structure is poor,

it will decrease nutrient intake by the crops and increase the risk of nutrient leaching and

erosion. Meanwhile, a good soil structure allows water infiltration into the soil, maintains the

temperature of the soil thus making it easy to cultivate (Kulmala, 2012).

Input of fertilizer into the soil through agricultural activities to increase fertility and

crop yield have great impact on the soil condition, besides other factors such as field age, crop

rotation, use of manure, drainage and cultivation techniques (Kulmala, 2012). Most of the

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pesticide and fertilizer input are introduced through cash cropping such as rubber, pepper and

cocoa because these crops are prone to pests.

2.8 Comparison between organic and non-organic fertilizer

Fertiliser is important to sustain high yield, in which the fertiliser can be in the form of organic

(manure) and chemical (non-organic). To improve Ca and Mg nutrition for the vines and to

raise the soil pH, liming material such as dolomite is used. Mature vines need lesser nutrients

such as NPK compare to younger or immature vines. However, substantial nitrogen and K are

required in mature pepper vines (Rosli et al., 2013).

Using manure for adding nutrients in the soil is not enough to produce better yield and

sufficient nutrients for the plant. Fertiliser is the alternative method in providing basic nutrient

for the soil and plant. Comparing crop yields with no nutrient inputs as the control, with crops

that received nutrients as either fertiliser or manures had very large effects (150-1000%) on

soil productivity. Organic matter and volume of microfauna are higher in manured soils

compared to fertilised soils, also more enriched in P, K, Ca and Mg in topsoils and nitrate N,

Ca and Mg in subsoils. Fertilised soil had higher bulk density and lower porosity, relative to

manured soils. However, there is no significant difference in long-term effects on crop

production between fertilisers and manures.

For the soil productivity, manures give more benefits when large inputs are applied

over many years due to their nutrient content. The ratio of nutrient manures is different from

the ratio of nutrient removed by common crops, therefore some nutrients, particularly P and

nitrogen are accumulated excessively for over long-term use of manures. Poor water quality

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also may arise from long-term use of manure by increasing its chemical oxygen demand and

therefore soil quality also will be affected in terms of productivity and potential to adversely

affect water quality (Edmeades, 2003).

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Chapter 3

METHODOLOGY

3.1 Study area

The study areas for the collected samples were from Kpg. Duyoh, Kpg. Stenggang, Kpg. Stass

and Kpg. Opar in Bau. Figure 3.1 to Figure 3.3 shows the map of the study sites and Table 1

shows the GPS coordinate for each study site.

Figure 3.1 Locations of Kpg. Stenggang and Kpg. Opar