Beach Morphodynamics and Coastal Processes Along Teluk Chempedak to Kuala Pahang, Pahang, Malaysia

BEACH MORPHODYNAMICS AND COASTAL PROCESSES ALONG TELUK CHEMPEDAK TO KUALA PAHANG, PAHANG, MALAYSIA

MOHD ZAINI BIN MUSTAPA

A thesis submitted in fulfilment of the requirement for the degree of Doctor of Philosophy in Education

Kulliyyah of Science International Islamic University Malaysia

FEBRUARY 2017

ABSTRACT

The present study on the beach morphology and its profile dynamics along the selected beach of Pahang comprising the areas from Teluk Chempedak to Kuala Pahang. Beach stations were monitored monthly for a complete 1-year cycle; beginning from February 2012 to February 2013 at 12 corresponding stations established at random morphological intervals. The aim of the study is to determine the morphological development of the respective beach based on profile alteration, including the erosional and depositional rates and other ambient littoral morphodynamic factors including sediment grain-size analysis. Topographic beach profiles were surveyed using an electronic theodolite in order to attain composite height, distance, and slope of the beach. Analysis on the beach process activity was extended for numerical modelling simulation in order to understand the physical processes involved. Analysis of beach profile changes revealed that minor changes at dune and high-tide zone with a negligible rate of either erosion or deposition for most stations. The northeast monsoon activity has transported the sediment away from the stations causing most stations experienced erosion. However, the process of deposition took place at most stations that could be noticed at the mid-tide level and some extent of low-tide areas throughout the post-northeast monsoon season. The beach slopes were ranged from 0.98° to 6.26° and indicates most beaches have a gentle slope with lower degree value. The quartz sand was found along the study area with domination of fine grain sediment with medium and coarse fractions obtained at certain sites. Model simulation implied that the selected domains are classified as transported area, which having more tendencies to become eroded if any disturbance introduced such as development to the area without proper design and planning. Periodically, changes in currents, tides and wave action, however, produced a normal cycle if the virginity of the beach remains unchanged. The necessity of understanding of these factors is high as to maintain the sustainability for both natural and human systems.

خالصة البحث ABSTRACT IN ARABIC

ُصممت هذه الدراسة لفهم تشكل الشاطئ والديناميكا اجلانبية على طول الشاطئ يف مناطق خمتارة من ابهانج تضم مساحات من شاطىء جيمباداك إىل كواال ابهانج. مت رصد حمطات الشاطئ الشهرية لدورة كاملة ملدة سنة؛ ابتداء من فرباير 2012 إىل فرباير 2013 يف 12 حمطة ومت إنشاء حمطات ماابلة يف فرتات مورفولوجية عشوائية. اهلدف من هذه الدراسة هو حتديد وضع تطور مورفولوجية الشاطئ املخصص إستناداً إىل التغيري يف احملتوى، مبا يف ذلك معدالت التحات والرتسيب وغريها من العوامل مورفوديناميكية الساحلية احمليطة مبا يف ذلك حتليل حجم حبات الرواسب. مت مجع مظاهر الشاطئ الطبوغرافية ابستخدام املزواة اإللكرتونية من أجل حتايق ارتفاع املركب وبعد املسافة وإحندار الشاطئ. مت متديد التحليل على نشاط عملية الشاطئ حملاكاة النماذج العددية من أجل فهم العمليات الفيزايئية املعنيّة. كشف حتليل حمتوى تغريات الشاطئ أن هنالك تغيريات طفيفة يف الكثبان الرملية ومنطاة املد مع معدل ال يذكر إما آتكل أو ترسيب ملعظم احملطات. وقد نال نشاط الرايح املومسية الشمالية الشرقية الرواسب بعيدا عن احملطات مما تسبب آتكل قوي يف معظم احملطات. ومع ذلك، جرت عملية الرتسيب يفمعظم احملطات اليت ميكن أن تكون يف مستوى منتصف املد والبعض موجود يف مناطق اجلزر طوال موسم الرايح املومسية ما بعد مشال شرق البالد. تراوحت إحندرات الشاطئ من 0.98 درجة إىل 6.26 درجة وتشري معظم الشواطئ هلا منحدر طفيف مع أقل قيمة. مت العثور على رمل الكوارتز على طول منطاة الدراسة مع هيمنة حبات الرواسب الناعمة مع كسور متوسطة وخشنة اليت مت احلصول عليها يف بعض املواقع. ابلنسبة جلزء اهليدروديناميكية، تضمن منوذج احملاكاة أن تصنف اجملاالت املختارة كمنطاة مناولة، اليت لديها املزيد من امليول لتصبح متآكلة إذا حدث أي اضطراب مثل تنمية املنطاة دون تصميم وختطيط سليم. على حنو دوري، التغريات يف التيارات واملد واجلزر وحركة األمواج، ومع ذلك، أنتاج دورة طبيعية للشاطئ دون تغيري. ضرورة فهم هذه العوامل هي مهمة للحفاظ على استدامة كل من النظم الطبيعية والبشرية.

iii

APPROVAL PAGE

The thesis of Mohd Zaini Mustapa has been approved by the following:

______Shahbudin Saad Supervisor

______Muhammad Salihi Abdul Hadi Co-Supervisor

______Kamaruzzaman Yunus Co-Supervisor

______Normawaty Mohammad Noor Internal Examiner

______Rosnan Yaacob External Examiner

______Ejria Saleh External Examiner

______Norlelawati A. Talib Chairman

DECLARATION

I hereby declare that this thesis is the result of my own investigations, except where otherwise stated. I also declare that it has not been previously or concurrently submitted as a whole for any other degrees at IIUM or other institutions.

Mohd Zaini Mustapa

Signature ...... Date ......

DECLARATION OF COPYRIGHT AND AFFIRMATION OF FAIR USE OF UNPUBLISHED RESEARCH

BEACH MORPHODYNAMICS AND COASTAL PROCESSES ALONG TELUK CHEMPEDAK TO KUALA PAHANG, PAHANG, MALAYSIA

I declare that the copyright holders of this thesis are jointly owned by the student and IIUM.

No part of this unpublished research may be reproduced, stored in a retrieval system, or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording or otherwise without prior written permission of the copyright holder except as provided below

1. Any material contained in or derived from this unpublished research may be used by others in their writing with due acknowledgement.

2. IIUM or its library will have the right to make and transmit copies (print or electronic) for institutional and academic purposes.

3. The IIUM library will have the right to make, store in a retrieved system and supply copies of this unpublished research if requested by other universities and research libraries.

By signing this form, I acknowledged that I have read and understand the IIUM Intellectual Property Right and Commercialization policy.

Affirmed by Mohd Zaini Bin Mustapa

……..…………………….. ……………………….. Signature Date

ACKNOWLEDGEMENTS

In the name of Allah, the Most Beneficent, the Most Merciful

Alhamdulillah, praised to Allah the Almighty for giving me great opportunity, time and patience without which this thesis would never have been completed.

Firstly, I would like to express my sincere and profound gratitude to my main supervisor, Assoc. Prof. Dr. Shahbudin Saad for his priceless and extensive knowledge along the way to complete this research. Without his invaluable guidance and encouragement, this thesis might not been completed successfully. To the members of my supervisory committee (Co-supervisors) namely Asst. Prof. Dr. Muhammad Salihi Abdul Hadi and Prof. Dr. Kamaruzzaman Yunus (Dean Kulliyyah of Science), thanks for the invaluable comments, views and ideas towards the betterment of this thesis.

I wish to express my appreciation and thanks to the Head of Department of Marine Science, Assoc. Prof. Dr. Normawaty Mohammad Noor for her kind help and motivation for me to achieve this goal in order to complete my PhD study. Thanks also the lecturers of Marine Science Department especially Dr. Zuhairi Ahmad, Dr. Siti Waznah Abdurahman and Dr. Ahmad Azfar Mohamed for their kind cooperation and support.

It is my utmost pleasure to dedicate this work to my dearest wife, Noraisyah Sapon for her endless support and help during research works and analyzing the data; to my cute little girl, Nur Amni Khadeeja; to my dear dad, Mustapa Bin Hamat and my siblings (Abe Kee, Abe Mat & Kak Ra) and family, who giving me the gift of their unwavering belief in my ability to accomplish this mission: thank you for your support and patience.

I am very thankful to the staff of Kulliyyah of Science and INOCEM especially to the former Director of INOCEM, Assoc. Prof. Dr. Mohamed Kamil Abd. Rashid; Science Officer, Br. Mohd Masrul Masduki, Assistant Science Officer, Br. Azizul Aziz and former Assistant Science Officers, Br. Khairul Ehsan Razali and Br. Huzifah Jaafar who had helped me a lot during the fieldwork and sampling activities.

I would like to extend my thanks and appreciation to my colleagues and friends especially Dr. Mohd Fuad Miskon, Br. Muhammad Faiz Mohd Hanapiah, Br. Muhammad Hamizan Yusof, Br. Mohd Husaini Rani, Br. Ali Abdallah Alqudah and Br. Tan Nai Han for their kind assistance and help.

Last but not least, I would like to thank to all person who are not mentioned here that had provided their time, effort and support for this project and had contributed directly or indirectly during the completion of this thesis, and for that, I will be forever grateful. Thank you.

vii

TABLE OF CONTENTS

Abstract ...... ii Abstract in Arabic ...... iii Approval Page ...... iv Declaration ...... v Copyright Page ...... vi Acknowledgements ...... vii List of Tables ...... xii List of Figures ...... xiv

CHAPTER ONE : INTRODUCTION ...... 1 1.1 Background ...... 1 1.2 Problem Statement ...... 3 1.3 Hypotheses ...... 5 1.4 Aim (General Objective) ...... 6 1.5 Specific Objective ...... 6 1.6 Thesis Outline ...... 7

CHAPTER TWO : LITERATURE REVIEW ...... 8 2.1 Overview...... 8 2.2 Beach Process ...... 10 2.2.1 Beach Morphology ...... 12 2.2.2 Beach Cycle ...... 15 2.2.3 Beach Profile Survey ...... 16 2.3 Sediment ...... 18 2.3.1 Sedimet Characteristics ...... 18 2.3.2 Grain-size Analysis...... 21 2.4 Atmospheric and Ocean Influence...... 24 2.4.1 Rainfall Distribution ...... 25 2.4.2 Wind ...... 26 2.4.3 Monsoon ...... 28 2.4.4 Wave ...... 29 2.4.5 Tide ...... 31 2.4.6 Current ...... 33 2.4.7 Bathymetry ...... 36 2.5 Geological Settings ...... 37 2.6 Anthropogenic Pressures ...... 40 2.7 Beach Management ...... 42

CHAPTER THREE : GENERAL METHODOLOGY ...... 44 3.1 Introduction ...... 44 3.2 Methods ...... 44 3.3 Study Sites Description ...... 49

viii

CHAPTER FOUR : BEACH-FACE MORPHODYNAMICS OF DISTINCT MORPHOLOGICAL SETTING ALONG TELUK CHEMPEDAK TO KUALA PAHANG ...... 53 4.1 Introduction...... 53 4.2 Study Area ...... 54 4.3 Materials and Methods ...... 55 4.3.1 Beach Profile/ Morphology ...... 55 4.3.2 Leveling ...... 57 4.3.3 Three-Dimensional (3D) Beach Interpretation ...... 59 4.3.4 Two-Dimensional (2D) Beach Profile ...... 59 4.3.5 Littoral Environmental Observation (LEO) ...... 59 4.4 Results and Discussion ...... 60 4.4.1 Analysis of Beach Profile and LEO ...... 61 4.4.1.1 Teluk Chempedak beach (Station 1) ...... 61 4.4.1.2 Taman Gelora beach (Station 2) ...... 64 4.4.1.3 Tanjung Lumpur beach (Station 3) ...... 67 4.4.1.4 Peramu beach (Station 4) ...... 70 4.4.1.5 Suntiana beach (Station 5) ...... 73 4.4.1.6 Kempadang beach (Station 6) ...... 76 4.4.1.7 Cempaka beach (Station 7) ...... 79 4.4.1.8 Sepat-A (Station 8) ...... 82 4.4.1.9 Sepat-B (Station 9) ...... 85 4.4.1.10 Cherok Paloh (Station 10) ...... 88 4.4.1.11 Serandu beach (Station 11) ...... 91 4.4.1.12 Kuala Pahang beach (Station 12) ...... 94 4.4.2 Dynamics of Beach Morphology ...... 97 4.4.2.1 Annual Beach Morphology Changes ...... 98 4.4.2.2 Seasonal Beach Morphology Changes ...... 101 4.4.3 Beach Slope ...... 108 4.4.4 Beach Volumetric Changes ...... 111 4.5 Summary ...... 113

CHAPTER FIVE : VARIATION IN TEXTURAL CHARACTERISTICS OF BEACH AND NEARSHORE SEDIMENTS ALONG TELUK CHEMPEDAK TO KUALA PAHANG ...... 114 5.1 Introduction ...... 114 5.2 Study Area ...... 115 5.3 Materials and Methods ...... 117 5.4 Result and Discussion ...... 120 5.4.1 Grain-size Analysis of Beach Sediment ...... 120 5.4.1.1 Mean Size...... 120 5.4.1.2 Sorting ...... 130 5.4.1.3 Skewness ...... 136 5.4.1.4 Kurtosis ...... 143 5.4.2 Shore Normal Observation ...... 149 5.4.2.1 Shore Normal Mean Size ...... 149 5.4.2.2 Shore Normal Sorting ...... 152 5.4.2.3 Shore Normal Skewness ...... 154 5.4.2.4 Shore Normal Kurtosis ...... 156

5.4.3 Bivariate Scatterplots ...... 158 5.4.3.1 Mean Size versus Sorting...... 159 5.4.3.2 Skewness versus Kurtosis ...... 160 5.4.3.4 Mean Size versus Kurtosis ...... 162 5.4.3.5 Mean Size versus Skewness...... 163 5.4.3.6 Sorting versus Skewness ...... 164 5.4.4 Grain-size Analysis of Nearshore Sediment ...... 165 5.4.4.1 Grain-size Analysis of Teluk Chempedak ...... 165 5.4.4.2 Grain-size Analysis of Sepat ...... 170 5.4.4.3 Grain-size Analysis of Kuala Pahang ...... 175 5.4.5 Relationship between Beach and Nearshore Sediments ...... 180 5.5 Summary ...... 181

CHAPTER SIX : HYDRODYNAMIC AND SEDIMENT TRANSPORT MODELLING ...... 182 6.1 Introduction ...... 182 6.2 Materials and Methods ...... 183 6.2.1 Study Area ...... 183 6.2.2 Model Description ...... 186 6.2.3 Model Input and Setup ...... 189 6.2.3.1 Triangular Mesh ...... 189 6.2.3.2 Surface Elevation ...... 193 6.2.3.3 Bed Resistance ...... 194 6.2.3.4 Wind Flow Velocity ...... 195 6.3 Results and Discussion ...... 197 6.3.1 Hydrodynamic of Kuantan coastal water ...... 197 6.3.1.1 Wave Refraction ...... 200 6.3.1.2 Model Validation...... 203 6.3.2 Sediment Transport of Kuantan coastal water ...... 204 6.4 Summary ...... 207

CHAPTER SEVEN : RELATIONSHIP BETWEEN BEACH TOPOGRAPHY, SEDIMENT VARIABILITY AND NUMERICAL MODELLING ...... 208 7.1 Introduction...... 208 7.2 Dynamic of Beach Topography and Sediment Characteristics ...... 208 7.2.1 Beach Changes in Different Domain Setting ...... 209 7.2.1.1 Teluk Chempedak (Headland Beach) ...... 211 7.2.1.2 Sepat (Open Beach) ...... 212 7.2.1.3 Kuala Pahang (Near to Estuary) ...... 213 7.2.2 Relationship between Beach Slope and Sediment Mean Size ...... 215 7.3 Beach Morphodynamic Classification ...... 219 7.3.2 Morphotype Classification Analysis ...... 221 7.3.3 Surf-Scaling (ξ) and Dimensionless Fall Velocity (Ω) ...... 224 7.3.4 Classification Parameters ...... 226 7.3.5 Classification Accuracy ...... 226 7.4 Shore Drift Determination ...... 227 7.5 Fall Velocity ...... 230

CHAPTER EIGHT : CONCLUSION AND RECOMMENDATION ...... 233

REFERENCES ...... 235

LIST OF TABLES

Table No. Page No.

Table 2.1 Mean vector of wind direction and speed 27

Table 3.1 Coordinate of Pahang Beach Sampling Stations 51

Table 4.1 Benchmark values for all stations correspond to mean sea level 58

Table 4.2 Date of beach profile measurements 58

Table 4.3 Littoral Environmental Observation data for Teluk Chempedak 63

Table 4.4 Littoral Environmental Observation data for Taman Gelora beach 66

Table 4.5 Littoral Environmental Observation data for Tanjung Lumpur beach 69

Table 4.6 Littoral Environmental Observation data for Peramu beach 72

Table 4.7 Littoral Environmental Observation data for Suntiana beach 75

Table 4.8 Littoral Environmental Observation data for Kempadang beach 78

Table 4. 9 Littoral Environmental Observation data for Cempaka beach 81

Table 4.10 Littoral Environmental Observation data for Sepat-A beach 84

Table 4.11 Littoral Environmental Observation data for Sepat-B beach 87

Table 4.12 Littoral Environmental Observation data for Cherok Paloh beach 90

Table 4.13 Littoral Environmental Observation data for Serandu beach 93

Table 4.14 Littoral Environmental Observation data for Kuala Pahang beach 96

Table 4.15 Summary of annual beach morphology changes 98

Table 4.16 Annual changes in beach slope 110

Table 4.17 Seasonal changes in beach slope 111

Table 4.18 Annual volumetric changes of sediment 112

Table 5.1 Statistical formula used to calculate the grain-size characteristics 120

Table 5.2 Mean sizes values (φ) of beach sands for each sampling stations 127

Table 5.3 Sorting coefficient (φ) of beach sands for each sampling stations 133

xii

Table 5.4 Skewness values (φ) of beach sands for each sampling stations 140

Table 5.5 Kurtosis values (φ) of beach sands for each sampling stations 146

Table 5.6 Grain-size analysis for Teluk Chempedak nearshore area 166

Table 5.7 Textural characteristic of Teluk Chempedak nearshore area 168

Table 5.8 Grain-size analysis for Sepat nearshore area 171

Table 5. 9 Textural characteristic of Sepat nearshore area 173

Table 5.10 Grain-size analysis for Kuala Pahang nearshore area 176

Table 5.11 Textural characteristic of Kuala Pahang nearshore area 178

Table 6. 1 Harmonic constant of tidal constituents of Kuantan 193

Table 7.1 Parameter of beach profile and sediment of domain area 214

Table 7.2 Parameters for high-wave energy beach states states 220

Table 7.3 Beach type, D50 (φ) and swash slope 223

Table 7.4 Surf-scaling parameter and dimensionless fall velocity 225

xiii

LIST OF FIGURES

Figure No. Page No.

Figure 2.1 Beach cross-shore profile taxonomy 13

Figure 2.2 Seasonal beach profile changes 15

Figure 2.3 The Wentworth Grade Scale 23

Figure 2.4 The distribution of monthly precipitation (in mm) in Peninsular Malaysia during the Northeast Monsoon 26

Figure 2.5 (a) Annual wind wave power and (b) Annual swell wave power; along the east coast of Peninsular Malaysia 30

Figure 2.6 The tidal levels based on Tanjung Gelang Standard Port 33

Figure 2.7 The surface currents of the South China Sea during (a) Northeast Monsoon and (b) Southwest Monsoon 34

Figure 2.8 Total sea surface current circulation pattern during (a) Southwest Monsoon; (b) Northeast Monsoon 35

Figure 2.9 Nearshore bathymetry contour fronting the coastline of Pahang 37

Figure 2.10 Geological map of Pahang coastline 40

Figure 3.1 Flow chart of the overall ideas of the research 46

Figure 3.2 Flow chart of the beach morphology and field measurement works 47

Figure 3.3 Flow chart of the numerical hydrodynamic modelling 48

Figure 3.4 Map showing the study area consists of 12 stations 52

Figure 4.1 A weatherproof total station equipment, Leica Builder 409 56

Figure 4.2 Beach profiling technique using total station equipment 56

Figure 4.3 Beach profiling method 57

Figure 4.4 Sequential 3D profile of Teluk Chempedak beach 62

Figure 4.5 Monthly cross-shore profile of Teluk Chempedak beach 63

Figure 4.6 Sequential 3D profile of Taman Gelora beach 65

Figure 4.7 Monthly cross-shore profile of Taman Gelora beach 66

xiv

Figure 4.8 Sequential 3D profile of Tanjung Lumpur beach 68

Figure 4.9 Monthly cross-shore profile of Tanjung Lumpur beach 69

Figure 4.10 Sequential 3D profile of Peramu beach 71

Figure 4.11 Monthly cross-shore profile of Peramu beach 72

Figure 4.12 Sequential 3D profile of Suntiana beach 74

Figure 4.13 Monthly cross-shore profile of Suntiana beach 75

Figure 4.14 Sequential 3D profile of Kempadang beach 77

Figure 4.15 Monthly cross-shore profile of Kempadang beach 78

Figure 4.16 Sequential 3D profile of Cempaka beach from 80

Figure 4.17 Monthly cross-shore profile of Cempaka beach 81

Figure 4. 18 Sequential 3D profile of Sepat-A beach 83

Figure 4.19 Monthly cross-shore profile of Sepat-A beach 84

Figure 4.20 Sequential 3D profile of Sepat-B beach 86

Figure 4.21 Monthly cross-shore profile of Sepat-B beach 87

Figure 4.22 Sequential 3D profile of Cherok Paloh beach 89

Figure 4.23 Monthly cross-shore profile of Cherok Paloh 90

Figure 4.24 Sequential 3D profile of Serandu beach 92

Figure 4.25 Monthly cross-shore profile of Serandu beach 93

Figure 4.26 Sequential 3D profile of Kuala Pahang beach 95

Figure 4.27 Monthly cross-shore profile of Kuala Pahang beach 96

Figure 4.28 Annual beach profile changes 99

Figure 4.29 Post-Northeast Monsoon beach profile changes 102

Figure 4.30 Pre-Northeast Monsoon beach profile changes 104

Figure 4.31 Northeast Monsoon beach profile changes 106

Figure 4.32 Periodical beach slope variation between stations 110

Figure 5.1 Map shows the beach and nearshore sediment station 116

Figure 5.2 Typical beach profile showing four different sub-environments 117

Figure 5.3 Flowchart of the sediment analyses works 118

Figure 5.4 Monthly mean sizes variable of beach sediment in a year cycle 125

Figure 5.5 Average mean size distribution over stations 129

Figure 5.6 Monthly sorting variation of beach sediment in a year cycle 131

Figure 5.7 Average sorting coefficient over stations 135

Figure 5.8 Monthly skewness variable of beach sediment in a year cycle 138

Figure 5.9 Average skewness distribution over stations 142

Figure 5.10 Monthly kurtosis variable of beach sediment in a year cycle 144

Figure 5.11 Average kurtosis distribution over stations 148

Figure 5.12 Mean size distribution over station of distinct tidal level 151

Figure 5. 13 Sorting distribution over station of distinct tidal level 153

Figure 5.14 Skewness distribution over station of distinct tidal level 155

Figure 5.15 Kurtosis distribution over station of distinct tidal level 157

Figure 5.16 Bivariate plot between mean sizes and sorting coefficient 160

Figure 5.17 Bivariate plot between skewness and kurtosis 161

Figure 5.18 Bivariate plot between mean sizes and kurtosis 162

Figure 5.19 Bivariate plot between mean sizes and skewness 163

Figure 5.20 Bivariate plot between sorting coefficient and skewness 164

Figure 5.21 Grain-size distribution of Teluk Chempedak nearshore area 167

Figure 5.22 Sediment texture of Teluk Chempedak nearshore sediment 168

Figure 5.23 Textural characteristics distribution of Teluk Chempedak nearshore 169

Figure 5.24 Grain-size distribution of Sepat nearshore area 172

Figure 5.25 Sediment texture of Sepat nearshore sediment 173

Figure 5.26 Textural characteristics distribution of Sepat nearshore area 174

Figure 5.27 Grain-size distribution of Kuala Pahang nearshore area 177

Figure 5.28 Sediment texture of Kuala Pahang nearshore sediment 178

xvi

Figure 5.29 Textural characteristics distribution of Kuala Pahang nearshore 179

Figure 6.1 Domain or sub-areas of numerical modelling 184

Figure 6.2 Summary of numerical modelling procedure 185

Figure 6.3 Triangular mesh generated in MIKE-21 191

Figure 6.4 Bathymetry map of Kuantan coastal area 192

Figure 6.5 Manning (M) map of Kuantan coastal area 194

Figure 6.6 Wind rose of Pahang coast during northeast monsoon 196

Figure 6.7 Wind rose of Pahang coast during southwest monsoon 196

Figure 6.8 Flow velocity during spring tide 198

Figure 6.9 Flow velocity during neap tide 199

Figure 6.10 Wave refraction of Teluk Chempedak 201

Figure 6.11 Wave refraction of Pantai Sepat 202

Figure 6.12 Wave refraction of Kuala Pahang 202

Figure 6.13 Regression analysis of current speed 203

Figure 6.14 Regression analysis of current direction 203

Figure 6.15 Sediment transport of Teluk Chempedak 205

Figure 6.16 Sediment transport of Sepat 205

Figure 6.17 Sediment transport of Kuala Pahang 206

Figure 6.18 Regression analysis of total suspended sediment 206

Figure 7.1 The relationship between mean grain size of high-tide (HT) and beach slope 217

Figure 7.2 The relationship between mean grain size of mid-tide (MT) and beach slope 217

Figure 7.3 The relationship between mean grain size of low-tide (LT) and beach slope 218

Figure 7.4 The relationship between mean grain size of swash-zone (SZ) and beach slope 218

Figure 7.5 Net Shore Drift (NSD) direction along the study area 229

xvii

Figure 7.6 Hjulstrom diagram for Teluk Chempedak 231

Figure 7.7 Hjulstrom diagram for Sepat 231

Figure 7.8 Hjulstrom diagram for Kuala Pahang 232

xviii

CHAPTER ONE

INTRODUCTION

1.1 BACKGROUND

Beaches and surf zones have been subjects of interest historically due to their dramatic variations in time and space (Souza, 2007) and are extremely unstable dynamic and active surroundings (Benassai, 2006; Delgado et al., 2002; Klein et al., 2002). It is one of the vulnerable zones which are affected by both man-made intervention, and natural phenomenon.

Human interaction with the beach cannot be separated as high dependency of human on the beach ecosystems and its resources. It is reported that human changes in beach surroundings began at least two centuries ago (Nordstrom, 2000), and are predicted to intensify over the next few decades (Brown et al., 2008). Human activities have placed high pressures on beach ecosystems as the growth of both population and economies continues (Bessa et al., 2014; Defeo et al., 2009; Nel et al.,

2014).

The beach area is unusual in character, being neither land nor sea and continuously alternating between being covered and uncovered by the sea. This alternating processes that changing the landscapes, shapes and features of the beach and termed as beach morphology. The beach morphology includes variability in spatial and temporal scales associated with sedimentary balance, source of sediments and depositional/erosional characters (Stanica & Ungureanu, 2010). There are various factors contributing to the changes of the beach morphology. This includes sediment characteristics and supply, variations in tidal currents, wave energy, wind action, tidal

inlet dynamics and morphological feedback (Bernabeu et al., 2003; Gunawardena et al., 2008; Karunarathna et al., 2012; Kroon et al., 2008).

Beach systems and its adjacent areas experience morphological variability encompasses from micro to macro scales; temporally - from a few seconds to decade, and spatially - from centimeter to kilometers (Carter, 2013). Rapid changes towards the beach environment, thus, affect the use of coastal areas that could be attributed to continuous interactions and processes as well as single catastrophic events which contribute to the shaping of coastal landscape (De Pippo et al., 2008). Integrated approaches through comprehensive study, for instance coastline mapping and numerical modelling, are therefore needed in order to deal with various challenges for better beach management purposes.

As a step to achieve this goal, a study related to beach morphology changes and its dynamic related processes was conducted in several beaches in Pahang (mostly located near the capital city of Kuantan) in order to define the features, formation and variability according to series of profile measurements and the associated grain-size and physical parameters. Several major problems faced by the beach ecosystems for instance erosion (Bruun, 1988; Thampanya et al., 2006; Tilmans, 1991), pollution

(Debrot et al., 2013; Omena et al., 2012; Tudor & Williams, 2003) and poor management due to lack of knowledge and awareness leads to instability of beach systems.

Therefore, better understanding of the magnitude and spatial-temporal behaviour of beach systems, in seasonal and long-term scales, is required to correctly plan beach management strategies. There are insufficient comprehensive studies of the characteristics and features of the Pahang beaches. Throughout this study, it is hopefully could provide a proper insight and information from multiple perspectives

in order to maintain the sustainability of beach resources and preserve the area for the future needs.

1.2 PROBLEM STATEMENT

Beaches in Malaysia can be broadly categorized into different characteristics; sandy, muddy and rocky shores. All beaches are subjected to the influenced of the dominant prevailing winds, namely, the northeast and southwest monsoons. Most sandy beaches

(as common in the eastern coast of Peninsular Malaysia and some part of Sabah) suggest that a state of dynamic equilibrium probably exists due to an establishment of a close process-form-relationship between energy input and the available material

(Del Rio et al., 2013).

Beach erosion is among the serious issues that draw attention from various parties not only from the public but also from the governmental sectors. Numerous developments have taken place in the low-lying coastal plain and involved reclamation of the beach components. Erosion of the coastline area is not a new matter, but of the recent past, it depicts interest largely due to economic activities being threatened. The important factor governing erosion of a beach is the long-shore sediment transport, which depends on the wave energy and the obliqueness of the breaking waves with reference to the shoreline projections. Long-shore transport also affects harbour development, siltation in tidal inlets, design of coastal structures, development of marinas and tourist resorts. Protection of coast against erosion is one of the challenging tasks for all coastal engineers.

The nature and complexity of most coastal problems vary widely with locations. Hence, a proper and desirable solution of any specific problem requires a systematic and thorough study of that area, particularly the beach area of Pahang

focuses on the area from Teluk Chempedak to Kuala Pahang coasts. For example, serious erosion problem is facing at several parts of the beaches in the study area such as Pantai Teluk Chempedak to Pantai Taman Gelora and along Pantai Sepat. As the beach areas always been an attraction to the people, many cases of death are reported every year due to drowning while bathing or swimming at the beach area, for example in Pantai Sepat (Nik Amirulmu'min, 2012; Mohd-Fairuz, 2012; Mohamad Shofi,

2012). This could be due to rip-current produced by the collision of two long-shore currents at certain beach cells or the existence of sandbar near the area that is dangerous to public particularly swimmers. Therefore, through this study for instance, the potential areas of rip current as well as the sandbars development could be predicted. The output of this research could be proposed to the Pahang state government in order to characterize the suitable and dangerous areas for the people to do their recreational and economic activities.

There are plenty of previous local studies pertaining to the beach processes, for example the beach development activities including profile alteration and sedimentary changes, which mostly focused on the littoral, attribute of the beach environment.

Even so, those studies are scattered, site-specific and not focused on integrating the available data for the current and future needs. For instance, studies conducted by

Rosnan (1989; 1991; 1995; 2002; 2003) and Mohd-Lokman et al. (1995; 1998) were mainly considered the beach profile changes and sediment (grain-size) characteristics without concerning really much on the physical processes that governs the changes in the littoral environment. In these cases, their discussions much rely on the explicit process (events that can be seen clearly) but fewer considerations were put towards the implicit processes (such as wave condition and current forces). Moreover, those studies were mainly carried out in the northern-region of the east coast of Peninsular

Malaysia, especially Terengganu while fewer studies are conducted near the proposed research area.

In order to generate better ideas regarding the beach dynamic processes in response to the temporal and spatial changes, the research finding will provide a good planning and better input for any relevant coastal management/engineering endeavours specifically on the study area, and generally to the subset of the Pahang coastal region. The output of this study is not only focused on beach morphodynamic activities, but also concerned with such factors as the sediment transport rate and sediment budget. Apart from that, the numerical modelling approach as practiced in this study is really helpful in order to understand the hydrodynamic process in a certain littoral environment and predict any changes that will happen in future. For example, the physical constituents of the beach process comprising wave refraction

(convergence and divergence forces) and long-shore current that are the main forces contributing in shaping the beach morphology and attribute shoreline.

1.3 HYPOTHESES

Several hypotheses are advanced and investigated as part of this study:

i. Changes in beach morphology are based on the alternation mechanism.

The rotational process of sediment transport (erosion and deposition)

creates a variety of beach profile and produces variable motions.

ii. It will be possible to identify trends in the grain size moments that will

mirror the sediment movement during different conditions such as

monsoon or inter-monsoon phases.

iii. The alteration of beach morphology is initiated by various physical forces

mostly by the wave and tidal action.

Investigation of the validity of these hypotheses will reveal important information on the usefulness of beach formation based on its morphological profiles and grain size derived statistics. Therefore, the analytical techniques in identifying the beach alteration in different environments (for instance headland-bay beach, estuarine- bay beach and open-system beach) could attest the variety of beach dynamic conditions.

1.4 AIM (GENERAL OBJECTIVE)

The aim of this research is to provide a better insight on understanding the physical processes of the beach environments along the study area particularly on identifying and recognizing the temporal and lateral changes of the beach morphology as well as other attribute parameters for example wave refraction, long-shore sediment transport and grain-size distribution.

1.5 SPECIFIC OBJECTIVE

The specific objectives of this study are as follows:

i. To investigate the temporal and spatial changes of the beach morphology,

including the erosion and deposition activities.

ii. To identify the sediment characteristics and its distribution as well as

beach morphodynamic classification along the study area.

iii. To determine the temporal and spatial changes of wave energy dissipated

via numerical modelling approaches.

iv. To define the sediment transport mechanisms that governs by the physical

forces, including wave dissipation activity (wave refraction) in terms of

sedimentation rate and volume of the selected beach domain.