UNIVERSITI PUTRA MALAYSIA

LEE YIT LENG

FP 2013 2

CARBON-SEQUESTERING ABILITIES OF PINEAPPLE LEAF RESIDUE CHARS AND THEIR DECOMPOSITION IN A TROPICAL PEAT

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CARBON-SEQUESTERING ABILITIES OF

PINEAPPLE LEAF RESIDUE CHARS AND

THEIR DECOMPOSITION IN A TROPICAL

PEAT

LEE YIT LENG

MASTER OF SCIENCE

2013

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CARBON-SEQUESTERING ABILITIES OF PINEAPPLE LEAF RESIDUE

CHARS AND THEIR DECOMPOSITION IN A TROPICAL PEAT

By

LEE YIT LENG

Thesis Submitted to the School of Graduate Studies, Universiti Putra Malaysia,

in Fulfilment of the Requirements for the Degree of Master of Science

January 2013

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Dear Dad, Kok Woon,

Mom, Oi Lien,

Beloved Brothers and Sister, Men Hau,

Men Huan, Yit Qing

Thank you for your love and support

Special Thanks to Wei Han

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Abstract of thesis presented to the Senate of Universiti Putra Malaysia in fulfilment

of the requirement for the degree of Master of Science

CARBON-SEQUESTERING ABILITIES OF PINEAPPLE LEAF RESIDUE

CHARS AND THEIR DECOMPOSITION IN A TROPICAL PEAT

By

LEE YIT LENG

January 2013

Chairman: Ahmad Husni bin Mohd. Hanif, PhD

Faculty: Agriculture

Oxidation of peat in combination with biomass burning on dry surface peat could

result in substantial carbon emissions to the atmosphere contributing to climate

change processes. Conversion of biomass into biochar is able to reduce CO2 levels in

the atmosphere by sustainably sequestering C. Field burning of pineapple leaf

residues (PLR) on peat is a traditional practice to prepare land for cultivation.

However, during the open burning not all of the PLR are converted into biochar but

ash will also be produced. Biochar produced under controlled combustion is

hypothesized to have better yield and quality, thereby better in sequestering C than

the biochar produced from the open burning. The study was undertaken to compare

the chemical properties and yields of PLR biochar produced by field burning (CF)

with that produced by a partial combustion of air-dried PLR in a furnace (CL).

Futhermore, the biochar decomposition with and without added fertilizer in the peat

were determined.

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Biochar produced by the CF and the peat samples were collected from Peninsula

Plantation, Johor, Malaysia. The CL biochar was produced by partially combusting

the PLR at 340°C for 3 hours in a furnace. Standard procedures were used to

determine the chemical properties of biochars produced by CL and CF. The

refractory nature of biochar samples were determined by analyzing the lignin content

and C/N ratio. The chemical functional groups of PLR and biochar samples were

identified using Fourier Transform Infrared Spectrocopy (FTIR). The decomposition

of biochars with and without added fertilizer on the tropical peat over 12 months

were determined using the litterbag method.

Total C (42.19%), lignin content (55.45%) and yield (5.63%) from CF was found to

be significantly lower than CL. Higher total C (53.30%), lignin content (63.34%),

and yield (33.71%) from CL as well as the presence of aromatic compounds in the

FTIR spectra of the CL biochar suggest that the CL process was better in

sequestering C than was the CF process. Although the C/N ratio (20.56) of biochar

produced from CL was significantly lower than CF (23.90), the C in the CL biochar

was dominated by lignin suggesting that the decomposition of biochar produced from

CL would be slow. Decomposition of CL and CF biochars in peat, with and without

added fertilizer, fit the three-parameter single exponential decay model.

Fertilizer treatment significantly reduced the weight and lignin remainings in the CL

and CF biochars after 12 months. The FTIR spectra showed the changes in the

functional groups of both biochars over 12 months were most likely the

transformation from aliphatic to aromatic functional groups. Total C remaining in the

biochar showed an increase in this order: CF + fertilizer (0.25 Mg/ha) < CF (0.31

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Mg/ha) < CL + fertilizer (2.05 Mg/ha) < CL (2.41 Mg/ha). To sequester C by biochar

application, the PLR could be partially combusted in a controlled process rather than

by burning in the field.

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Abstrak tesis yang dikemukakan kepada Senat Universiti Putra Malaysia sebagai

memenuhi keperluan untuk ijazah Master Sains

KEUPAYAAN ARANG SISA DAUN NANAS DALAM MENSEKUESTASI

KARBON DAN PEREPUTANNYA DI TANAH GAMBUT TROPIKA

By

LEE YIT LENG

Januari 2013

Pengerusi: Ahmad Husni bin Mohd. Hanif, PhD

Fakulti: Pertanian

Pengoksidaan tanah gambut dengan pembakaran sisa tanaman atas permukaan tanah

gambut yang kering boleh menyebabkan pelepasan karbon yang tinggi ke atmosfera

dan mengakibatkan proses perubahan iklim. Penukaran bentuk sisa tanaman kepada

arang boleh mengurangkan kandungan karbon dioksida dalam atmosfera dengan cara

mensekuestasi karbon secara mampan. Pembakaran daun nanas secara terbuka biasa

diamalkan untuk penyediaan tanah semasa penanaman semula. Walaubagaimanapun,

pembakaran sisa daun nanas (PLR) tidak akan membentuk arang sepenuhnya, tetapi

kebanyakannya akan menjadi abu. Hipotesis kajian menyatakan bahawa penghasilan

arang PLR melalui pembakaran terkawal adalah lebih tinggi hasilnya dan lebih

berkualiti dari segi pensekuestasian karbon berbanding dengan arang yang dihasilkan

secara pembakaran terbuka. Kajian ini dijalankan untuk menbandingkan sifat-sifat

kimia dan jumlah hasil arang PLR yang dihasilkan daripada pembakaran secara

terbuka (CF) dan pembakaran terkawal daun nanas dalam relau (CL). Seterusnya,

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kajian dijalankan untuk mengenalpasti pereputan pada arang yang diberi rawatan

baja dan tanpa rawatan baja di tanah gambut.

Sampel arang yang dihasilkan daripada proses CF dan sampel tanah gambut telah

dikumpulkan dari Peninsula Plantation, Johor, Malaysia. Sampel arang yang

dihasilkan daripada CL proses diperoleh daripada pembakaran PLR dalam relau pada

suhu 340°C selama 3 jam. Prosedur setaraf digunakan untuk menentukan sifat-sifat

kimia arang PLR yang dihasilkan daripada proses CL dan CF. Sifat refraktori sampel

arang juga ditentukan dengan meggunakan cara menganalisis kandungan lignin dan

nisbah C/N. Selain itu, kumpulan berfungsi kimia pada PLR dan sample arang

dikenalpasti dengan kaedah Fourier Transform Infrared Spectroscopy (FTIR). Tren

pereputan arang PLR di tanah gambut dengan rawatan baja dan tanpa baja ditentukan

dengan menggunakan kaedah penanaman beg nilon yang diisi dengan arang.

Kandungan karbon (42.19%), lignin (55.45%) dan hasil arang (5.63%) dalam proses

CF adalah didapati lebih rendah daripada proses CL. Kandungan karbon (53.30%),

lignin (63.34%) dan hasil arang (33.71%) yang lebih tinggi serta sebatian aromatik

yang didapati pada FTIR spektrum dalam proses CL menunjukkan keberkesanan

lebih tinggi dalam mensekuestasi karbon berbanding dengan arang yang dihasilkan

dalam proses CF. Walaupun arang yang dihasilkan daripada proses CL mempunyai

nisbah C/N (20.56) lebih rendah daripada CF (23.90), tetapi kedominasian

kandungan karbon oleh lignin menyebabkan proses pereputannya menjadi lebih

perlahan berbanding dengan proses pereputan arang hasil daripada proses CF.

Pereputan arang yang dihasilkan daripada proses CL dan CF dengan rawatan

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mahupun tanpa rawatan baja adalah bersesuaian dengan model pereputan eksponen

tunggal tiga-parameter.

Rawatan baja nyata mengurangkan berat dan kandungan lignin dalam arang CL dan

CF selepas 12 bulan pereputan. FTIR spektrum bagi kedua-dua proses menunjukkan

perubahan dari segi kumpulan berfungsi di mana kumpulan berfungsi alifatik

berubah kepada kumpulan berfungsi aromatik dalam jangka masa 12 bulan. Jumlah

kandungan karbon dalam arang menunjukkan peningkatan dengan susunan rawatan

berikut: CF + baja (0.25 Mg/ha) < CF (0.31 Mg/ha) < CL + baja (2.05 Mg/ha) < CL

(2.41 Mg/ha). Justeru, PLR sewajarnya dibakar dalam proses terkawal berbanding

dengan proses pembakaran secara terbuka di ladang supaya lebih banyak karbon

mampu disekuesterkan dalam aplikasi arang.

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ACKNOWLEDGEMENTS

The author grateful to Lord Almighty for his grace, blessings, and the strength

granted to her to complete her study. The author wishes to express her sincere

gratitude to Assoc. Prof. Dr. Ahmad Husni bin Mohd. Hanif the Chairman of the

Supervisory Commitee for the keen interest, valuable contribution and tireless

guidance during the preparation of this thesis. His countless support and generosity

cannot be over emphasized.

The author express her deepest gratitude to Dr. Samsuri Abdul Wahid, the member

of the Advisory Commitee for his invaluable assistance and guidance at the various

stages of the research. His tolerance and patient in this study a very much

appreciated. It is the thankfulness of the author to the entire management of Simpang

Rengam Pineapple Estate, Johor, with special reference to Mr Koh Soo Koon for the

commitment of the partnership in this collaborative research. The financial support

received from the Ministry of Higher Education, Malaysia, via Universiti Putra

Malaysia (UPM) are acknowledged.

Sincere appreciation goes to my family for their love, understand, spiritual support

and prayers. The author is thankful to the entire technical staff of the Land

Management Department for their diverse cooperation that led to the smoonth run of

all the experiments of the research. Help from friends is gratifying.

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I certify that a Thesis Examination Committee has met on 11 January 2013 to

conduct the final examination of Lee Yit Leng on her thesis entitled “Carbon-

Sequestering Abilities of Pineapple Leaf Residue Chars and Their Decomposition in

a Tropical Peat” in accordance with the Universities and University Colleges Act

1971 and the Constitution of the Universiti Putra Malaysia [P.U.(A) 106] 15 March

1998. The Committee recommends that the student be awarded the Master of

Science.

Members of the Thesis Examination Committee were as follows:

Mohd Khanif bin Yusop, PhD

Professor

Faculty of Agriculture

Universiti Putra Malaysia

(Chairman)

Rosenani Binti Abu Bakar, PhD

Professor

Faculty of Agriculture

Universiti Putra Malaysia

(Internal Examiner)

Osumanu Haruna Ahmed, PhD

Associate Professor

Faculty of Agriculture and Food Science

Universiti Putra Malaysia Kampus Bintulu Sarawak

(Internal Examiner)

Robert Thomas Bachmann, PhD

Associate Professor

Malaysian Institute of Chemical and Bioengineering Technology

Universiti Kuala Lumpur

(External Examiner)

_______________________________

SEOW HENG FONG, PhD

Professor and Deputy Dean

School of Graduate Studies

Universiti Putra Malaysia

Date: 30 April 2013

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This thesis was submitted to the Senate of Universiti Putra Malaysia and has been

accepted as fulfilment of the requirement for the degree of Master of Science. The

members of the Supervisory Commitee were as follows:

Ahmad Husni Mohd. Hanif, PhD

Associate Professor

Faculty of Agriculture

Universiti Putra Malaysia

(Chairman)

Samsuri Abdul Wahid, PhD

Senior Lecturer

Faculty of Agriculture

Universiti Putra Malaysia

(Member)

______________________________

BUJANG BIN KIM HUAT, PhD

Professor and Dean

School of Graduate Studies

Universiti Putra Malaysia

Date:

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DECLARATION

I declare that the thesis is my original work except for quotations and citations which

have been duly acknowledged. I also declare that it has not been previously, and is

not currently, submitted for any other degree at Universiti Putra Malaysia or at any

other institution.

____________________

LEE YIT LENG

Date: 11 January 2013

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TABLE OF CONTENTS

Page

DEDICATION ii

ABSTRACT iii

ABSTRAK vi

ACKNOWLEDGEMENTS ix

APPROVAL x

DECLARATION xii

LIST OF TABLES xvii

LIST OF FIGURES xviii

LIST OF ABBREVIATIONS xix

CHAPTER

1 INTRODUCTION 1

2 LITERATURE REVIEW 4

2.1 Characteristics of Tropical Peat 4

2.1.1Crops Cultivation in Tropical Peat 5

2.2 Pineapple Plantation in Malaysia 6

2.2.1 Pineapple Cultivation on Peat and Dry Matter 6

Production of Pineapple

2.3 Burning Practice in Pineapple Plantation 7

2.3.1 The Process and Products of Vegetation Fire 8

2.3.2 Advantages and disadvantages of Burning in 9

the Plantation

2.4 The Carbon Cycle 10

2.4.1 Carbon Fluxes in Peatland 10

2.5 Benefits of Biomass Conversion into Biochar 11

2.5.1 Biochar Amendments on Soil and Nutrient 12

Availability

2.6 Disadvantages of Biomass Conversion into Biochar 13

2.7 The Biochar Processing 13

2.7.1 Biochar Production in Closed Systems 14

2.7.2 Biochar Production by Field Burning 14

2.8 Chemical Properties of Biochar 15

2.8.1 Elemental Composition of Biochar 15

2.8.2 Surface Area and Functional Groups of Biochar 16

2.8.3 Lignin and Cellulose Contents of Biochar 17

2.9 Factors Influencing Biochar Properties 17

2.9.1 Vegetation 17

2.9.2 Charring Temperature 18

2.10 Comparison of C Stability between Biomass and Biochar 19

2.10.1 The Carbon Stability of Pineapple Leaf 20

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Residues

2.10.2 The Carbon Stability of Biochar 20

2.11 Decomposition and Chemical Changes of Biochar 21

in soil

2.12 Factors Influencing the Biochar Decomposition 22

2.12.1 Biochar Production Conditions 22

2.12.2 Lignin Content and C/N ratio of Biochar 23

2.12.3 Anaerobic and Aerobic of Soil Conditions 23

2.12.4 Soil Properties 24

2.12.5 Addition of Nutrients 24

2.13 Summary 25

3 CHARACTERISTICS OF PINEAPPLE LEAF 28

RESIDUE BIOCHARS PRODUCED BY CONTROL

COMBUSTION AND FIELD BURNING

3.1 Introduction 28

3.2 Materials and Methods 30

3.2.1 Field Burning-generated Biochar 30

3.2.2 Laboratory-generated Biochar 31

3.2.3 Chemical Analysis of Tissue and Biochar 31

3.2.3.1 pH and Electrical Conductivity (EC) of Biochar 31

3.2.3.2 Total C and N Analysis 31

3.2.3.3 Total Macronutrient Analysis 33

3.2.3.4 Cation Exchange Capacity (CEC) of Biochar 33

Determination

3.2.3.5 Lignin and Cellulose Determination 34

3.2.3.6 Fourier Transform Infrared Spectroscopy (FTIR) 35

of Tissue and Biochar Samples

3.2.3.7 BET Surface Area of Biochar Samples 36

3.2.4 Statistical Analyses 36

3.3 Results and Discussion 37

3.3.1 The Processing Conditions for Biochar Samples 37

Generated from CL and CF

3.3.2 Chemical Properties of PLR 38

3.3.3 Yield of Biochars Produced by CL and CF 39

3.3.4 Chemical Properties of Biochars Produced from 40

CL and CF Processes

3.3.4.1 pH, EC, TC, N contents and C/N Ratio of 40

Biochar

3.3.4.2 Cellulose and Lignin Contents of Biochar 42

3.3.4.3 Total P, K, Ca, Mg Concentrations and CEC 43

of Biochar

3.3.4.4 Surface Area of Biochars Produced from CL 44

and CF Processes

3.3.5 FTIR Spectra of PLR, Biochars Generated by CL 45

and CF

3.3.6 The Stability of Biochars Produced by the CL and 49

CF Processes

3.4 Conclusion 50

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4 CARBON STABILITY OF PINEAPPLE LEAF 51

RESIDUE BIOCHAR AND ITS DECOMPOSITION

IN PEAT

4.1 Introduction 51

4.2 Materials and Methods 53

4.2.1 Decomposition Study 53

4.2.2 Decomposition Study for Field Experiment 53

4.2.3 Decomposition Study for Pot Experiment 54

4.2.3.1 Experimental Site and Treatments 54

4.2.3.2 Fertilizer Forms and Rates 54

4.2.3.3 Pot Preparation 54

4.2.3.4 Peat Sampling and Preparation 55

4.2.4 Chemical Analysis of Peat and Biochar After 56

Pot and Field Experiments

4.2.4.1 pH and EC of peat 56

4.2.4.2 Total C and N Analysis of Peat as well as

Determination of Total C Remaining in Biochar

After Pot and Field Experiments

4.2.4.3 Determination of Peat Available P Content 56

4.2.4.4 Determination of Peat Available K, Ca, Mg 57

and CEC

4.2.4.5 Lignin and Cellulose Determination of Peat 57

and Biochar Remainings

4.2.4.6 FTIR of Biochar Samples from Pot and Field 58

Study

4.2.5 Decomposition Model 58

4.2.6 Statistical Analyses 58

4.3 Results and Discussion 60

4.3.1 Chemical Characteristics of Peat for Pot Study 60

4.3.2 Chemical Characteristics of Peat for Field Study 61

4.3.3 Decomposition of Laboratory- and Field-generated 63

Biochars

4.3.4 Lignin Content (%) after the Biochar 68

Decomposition

4.3.5 Total C after the Biochar Decomposition 71

4.3.6 Cellulose Content (%) After the Biochar 74

Decomposition

4.3.7 FTIR Spectra of Biochars Produced by CL and CF 76

Processes with and without Added Fertilizer

over 1 Year Decomposition

4.3.8 FTIR Spectra of Lignin Component Extracted 80

from Biochars Produced by CL and CF

Processes with and without Added Fertilizer

over 1 Year Decomposition

4.3.9 Total C Remains in Fresh and Charred PLR after 83

Decomposition in Pot Experiment

4.4 Conclusion 85

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5 SUMMARY, GENERAL CONCLUSION AND 86

RECOMMENDATION

REFERENCES/BIBLIOGRAPHY 88

APPENDICES 101

BIODATA OF STUDENT 106

LIST OF PUBLICATIONS 107