Luận văn Vulnerability assessment of freshwater reources in island to environment change a case study in Phu Quoc island – Kien Giang province
MINISTRY OF EDUCATION AND TRAINING
MINISTRY OF AGRICULTURE AND RURAL DEVELOPMENT
THUYLOI UNIVERSITY
VULNERABILITY ASSESSMENT OF FRESHWATER
RESOURCES IN ISLAND TO ENVIRONMENT CHANGE
A CASE STUDY
IN PHU QUOC ISLAND – KIEN GIANG PROVINCE
NGUYEN TIEN QUANG
MSc Thesis on Integrated Water Resources Management
May 2015
MINISTRY OF EDUCATION AND TRAINING
MINISTRY OF AGRICULTURE AND RURAL DEVELOPMENT
THUYLOI UNIVERSITY
NGUYEN TIEN QUANG
VULNERABILITY ASSESSMENT OF FRESHWATER
REOURCES IN ISLAND TO ENVIRONMENT CHANGE
A CASE STUDY
IN PHU QUOC ISLAND – KIEN GIANG PROVINCE
Major: Integrated Water Resources Management
THESIS OF MASTER DEGREE
. Supervisor (s):
1. Assoc. Prof. Dr Pham Thi Minh Thu
2. Assoc. Prof. Dr. Huynh Phu
This reseacrch is done for the partial fulfilment of requirement for
Master of Science Degree at Thuy Loi University
(This Mater Programme is supported by NICHE – VNM 106 Project)
May 2015
1
CHAPTER 1: INTRODUCTION
1.1. Problem statement
Water is our most precious resource. However, in recent years, water has
become degraded in both quantity and quality. This situation is placing challenges
and requires a worldwide effort in the use and sustainable management of water
resources. The provision of water supply and sanitation has improved living
conditions; in addition, the implementation of social justice and educational
approaches, especially for women and children, are also contributing to the success
of the enactment of the Millennium Development Goals (MDG).
The development status of the Island, the isolation characteristic, the
distance between neighboring islands, between islands and the mainland, the
change of the environment, climate change, changes in rainfall, etc. are the
challenges of water resources management. The Island, located in the lower floor of
the Southwestern area, is a vulnerable area to climate change and sea level rise.
Furthermore, the island is affected by the early phase of the El Nino and La Ninas.
The Island is a key economic zone with typical activities, such as: fishing, oil and
gas exploitation, maritime services, tourism as well as it is adjacent to the other
countries in the region.
Especially, Phu Quoc Island is the largest island in the coastal island system
in Vietnam. The current status of the economic development has created a
significant social pressure on the island regarding both system resources and the
environmental management. There is no rational planning and efficient use of
natural resources, although the extraction (water, oil, gas...) has been carried out for
a long time. Therefore, freshwater resources in Phu Quoc Island are vitally
important, and have a direct impact on daily life, and the development of the island.
The assessment of freshwater resource vulnerability in Vietnam is still very limited,
particularly in the Island. A vulnerability assessment of freshwater resources in Phu
2
Quoc Island will be essential to identify potential risks for fresh water resources on
the island and to support decision making; Therefore, detecting early threats to gain
insight sustainable solutions to the management of freshwater resources on an
island, where the exploitation of freshwater resources management is still
problematic.
Understanding the vulnerability of freshwater resources of the Islands,
therefore, is important to ensure sustainable water management in the region. Uses
of water have an intimate relationship with land use and impact on ecosystems
dealing with integrated water resource management. The integrated water resources
management will help to use and to protect natural resources. In order to effectively
implement integrated water resource management, the necessity of understanding
and the ability to assess the vulnerability of water resources are highlighted.
Performing a vulnerability assessment of freshwater will highlight gaps in
information and identify the most influential factors affecting vulnerability, in
addition to raising public awareness. The availability of such an evaluation would
provide decision-makers with the option to evaluate and modify existing policies
and to implement measures to improve the management of water resources.
Different approaches to vulnerability assessment of water resources and
hydrological systems have been developed for a long time with both advantages and
disadvantages. One of the most effective responses, vulnerability assessment has
recently been developed by the United Nations Environment Program and by
Packing University. This approach is based on the available resources to meet the
production, use, environmental pressures mitigation and capacity development and
management. It highlights the vulnerability factors such as climate change,
population growth, economic development, and management, etc. of vulnerable
freshwater resources. Currently, this method is implemented in the Pacific Islands,
in West and South Asia, in the Mekong River basin, and in several other river
basins in Vietnam. However, the vulnerability assessment of freshwater resources
on islands in Vietnam is very limited and this method is still not an application
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option. Hence, this study can be considered as a the first application of this approach
assessing freshwater vulnerability on islands in Vietnam.
1.2. Objectives and Research questions
1.2.1. Objective of study
The main objectives of the study include:
- Piloting a method in terms of assessing the freshwater vulnerability in the
southwestern area of Vietnams: applied specifically on Phu Quoc – Kien Giang
Province;
- Assessing vulnerability of freshwater resources on the Island of Phu Quoc –
Kien Giang and potential agents;
- Providing scientifically-based evidence to support policy development of water
resources management, to support the decision-making process;
- Proposing measures to reduce the vulnerability of freshwater resources on the
Phu Quoc Island.
1.2.2. Research questions
- What methods and tools are appropriate to assess the vulnerability of
freshwater resources on the Island?
- Which elements are vulnerable to freshwater resources?
- What are the opportunities and challenges regarding to freshwater resources
management in the Island?
- What are solutions that should be done to improve the freshwater resources in
the Island?
1.3. The Assessment Process
Water is essential for life. All activities of humans, animals and plants on
earth need water. However, freshwater resources are vulnerable and a reliable
assessment of vulnerability is essential. The vulnerability assessment of freshwater
resources, newly developed by UNEP (United Nations Environment Program) and
by Peking University is the methodology of the thesis. Firstly, relevant data in the
study area are collected, including: relevant documents such as natural conditions,
hydrology, environment, geology, etc. The statistical analysis results are collected
4
directly from the local agencies. The data processing is necessary to investigate
additional fieldwork and to update the latest data content research serving as the
current status and characteristics of water resources on the island and the control
system influence of the current vulnerability of freshwater resources. This study will
provide an overview of the evaluation method to assess the vulnerability of water
resources; the preferred method will be the approach developed by UNEP (United
Nations Environment Program) and Packing University. The evaluation of data will
serve an analytical framework DPSIR (Driver, pressure, state, impact and response)
to analyze quantitative and qualitative features, and a description of the
vulnerability of freshwater resources on the island. Then, an integrated vulnerability
index (VI) is calculated based on possible vulnerable parameters; the results will
assess the vulnerability of freshwater resources on the island, followed by a
proposal for solutions to reduce the vulnerability of freshwater resources on the Phu
Quoc Island.
1.4. Structure of the thesis
This report is divided into six chapters. The first chapter introduces the
research to answer three main questions: Why is a vulnerability assessment is
important? How can we assess the vulnerability of the island? And, what are the
main objectives of a vulnerability assessment in this study?
The chapter two reviews several studies about the concept of vulnerability,
vulnerability assessment methods and some previous researches relate to study area.
The chapter three presents an overview of freshwater resources, which
describe the geographical context of natural, socio-economics, freshwater resources.
Especially, we focus on the present status and the challenges dealing with the
management of fresh water resources in the island. This chapter also discusses the
importance of the influence of climate change and the pressures of environmental
change to freshwater resources on the island.
Chapter four identifies methods to assess the vulnerability of freshwater
resources, summarizes the specific assessment method of UNEP, including, such as:
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methods, diagnosis of issues, and DPSIR analytical framework to understand the
vulnerability index (VI). Data used in the thesis.
Chapter five is an important chapter of the report. This chapter continues to
assess the vulnerability of freshwater resources on the island of Phu Quoc – Kien
Giang Province. These assessments determine the importance and the
interrelationship of social-economics, the environment, climate, geographical
factors and management resources with vulnerable island freshwater resources. The
study of assessment indicators and injury parameters such as water stress,
development pressure, the insecurity of the ecosystem and management challenges,
is necessary to calculate the vulnerability index. In addition, this chapter will
provide proposed measures to reduce the vulnerability of freshwater resources on
the Island.
Chapter six: Finally, the last chapter concludes the findings of this thesis,
discusses the limitations of this work and provides an outlook by giving
recommendation for future areas of research.
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CHAPTER 2: LITERATURE REWIEW
2.1. Concepts of vulnerability
The concepts of vulnerability have been changed over time. According to
Jörn Birkmann (2006) statistics, the current literature encompass more than 25
different definitions, concepts and methods to systematize vulnerability (for
example, Chambers, 1989; Bohle, 2001; Wisner et al., 2004; Downing et al., 2006;
UN/ISDR, 2004; Pelling, 2003; Luers, 2005; Green, 2004; UN-Habitat, 2003;
Schneiderbauer and Ehrlich, 2004; van Dillen, 2004; Turner et al., 2003; Cardona,
2004b). According to Downing (2006), the vulnerability includes the expression,
sensitivity and resilience of the system to combat the dangers posed by the effects of
the agent. Researchers in the field of natural sciences often focus on the concept of
risk, while researchers in the field of social sciences often refer to the term
vulnerability. Concept of vulnerability is the social scientists associated with the
group of socioeconomic factors and the community's ability to cope with natural
disasters, but scientists about climate usually consider the concept of vulnerability
as a function of the likelihood of occurrence and the potential impact of weather and
climate related.
According to Jörn Birkmann (2006) statistics, one of the best-known
definitions were formulated by the International Strategy for Disaster Reduction
(UN/ISDR), which defines vulnerability as:
- The conditions determined by physical, social, economic and environmental
factors or processes, which increase the susceptibility of a community to the impact
of hazards. (UN/ISDR, 2004).
- In contrast, the United National Development Programme (UNDP) defines
vulnerability as: a human condition or process resulting from physical, social,
economic and environmental factors, which determine the likelihood and scale of
damage from the impact of a given hazard. (UNDP, 2004: 11)
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Develop policies of integrated water resources management will require a
comprehensive knowledge, the understanding of the vulnerability of water resources
is a key element for this purpose. Vulnerability is a term used to describe a weakness
or flaw exists in the system, the sensitivity of the system with a threat or a particular
disadvantage, and/or challenges systems faced when dealing with the threat.
In view of water resource management, the vulnerability can be defined as
the characteristic weaknesses and flaws of the system of water resources makes it
difficult to respond to changing economic and social and the environment. Thus, the
vulnerability can look through (i) the pressure of the water resources in the study
area; and (ii) the ability of ecosystems and society in the fight against the agents
acting on the healthy function of water resource systems.
2.2. Vulnerability assessment
Water, "blood" of natural ecosystems, have a role indispensable for almost
all functions of ecosystems. Water is also one of the important resources needed to
support the socioeconomic development of human. The result of the excessive
population growth, rapid economic development, mismanaged of water resources,
leading to dwindling water resources. Therefore, sustainable water resources
management has become a priority concern of many national agendas.
Vulnerability assessment is a process of investigation and analysis to assess
the sensitivity of the system before the potential threat, and to identify the main
challenges for the system in reducing or minimize the risks associated with, the
negative consequences of the opposition activists. Assessment of water resources
will be calculated based on the water balance between water supply and water
demand, system policies and ownership to support the conservation and management
of water resources, as well as regime change hydrology under the impact of climate
change and other environmental factors. Besides, It needs to consider the risks that
may occur from the surrounding areas can affect water resources.
The vulnerability assessment can be used to orient the rational use of water
resources through the provision of a priority plan for upgrades, adjusted operating
8
procedures, and/or change the policies to reduce risks and vulnerabilities to achieve
the most efficient use. Vulnerability assessment will provide the basic framework
for the development of options to reduce the risks and costs involved. In fact, every
problem is identified, vulnerability assessment to delimit the main control factor;
estimate the pressure; understand the current situation and development trend;
impact analysis; and determine the response to deal with vulnerability of water
resources systems.
2.3. Previous studies in study area
Phu Quoc Island is the largest island in the system of the coastal islands of
Vietnam. Phu Quoc Island in the Gulf of Thailand, the Southwestern of Vietnam.
The studies related to the Island's water resources are very limited. The coastal
islands Southwestern systems have a very important position on national security
and economic development. Some typical projects in the Phu Quoc Island area are:
- In 2006, Dr. Dao Manh Tien and Dr. Pham Van Thanh to implement the
project "Investigation assesses the current state of the marine environment of Phu
Quoc Island from 0 - 20m". The results were evaluated of marine resources Phu
Quoc island, the environmental status of sediments and seawater.
- Dr. Dao Manh Tien (2008) to implement the project "Investigation of
environmental geology and geohazards coast of Phu Quoc - Ha Tien rate
1/100,000".
- Within the scope of Phu Quoc Island and especially the National Park, this
area has had plenty of the study of biological diversity. The survey results synthetic,
fauna and flora of the area by the Institute of Forest Inventory and Planning II
performed (1996, 2002). This is the basis of the results are to assess, comment on
diversity and biological resources of Phu Quoc National Park.
- NAWAPI - National Center for Water Resources Planning and
Investigation (2010), Project “Water Resources Planning on the Phu Quoc Island”.
Planning is approved as the basis for the management agency of water resources
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Kien Giang Province implementation of management measures, protection and
exploitation and use of water resources on the Phu Quoc Island.
- Vietnam Academy for Water resources (2010), Project “ Research,
evaluate the potential exploitation of surface water sources serving water supply on
Phu Quoc Island”.
The previous studies in Vietnam, not to mention much of each object on the
Island are harmed by the activities of socioeconomic development, or the natural
environment changes. In Vietnam, Vulnerability assessment of freshwater
resources is limited, especially object is the island, where the water resources are
very vulnerable.
2.4. Overview of assessment methods
An approach to assess the vulnerability of water resources and hydrological
system has been developed for a long time, with many different methods. Such as
Water Poverty Index (WPI) – (Lawrence and others 2002; Sullivan and others
2003), with the aim is to provide an interdisciplinary measure, including the benefits
associated with household water and indicate the level of water availability affect
humans, the index takes into account the physical and social - economic factors
related to water scarcity.
Water Stress Indicator WSI description available water resources in a
country, the water stress index developed by Swedish Falkenmark expert 1989.
This index is often used in the evaluation on a national scale which data are
available and provided intuitive results and understanding. However, the use of
average annual water of the country should tend to obscure information water
scarcity on a smaller scale.
Meigh and others (2004) have developed a water availability index Water
Availability Index (WAI). The index includes surface water, groundwater and
compared to the total water demand of all sectors such as industry, agriculture, etc.
Or water stress (Gleick 1996) at the regional level. The index uses measurements of
input, output, and based on the water balance equation.
10
Or The South Pacific Applied Geoscience Commission (SOPAC) has
vulnerability index to demonstrate the disadvantages, which the small islands are
incurring. This index focuses on the vulnerability of the environment from the risks
of natural and human. Including the effects on physical and biological aspects of
the ecology, habitat, biodiversity, ecological resilience etc.
There are many different evaluation methods to be studied and applied, with
both advantages and disadvantages. For the vulnerability assessment of water
resources in recent years, Method of water resources vulnerability assessment,
developed by UNEP and Peking University (2009) emerged a way to evaluate the
effectiveness and advantages. With the approach depending on the resources
available to meet the production, use, environmental pressures and capacity
development and management. It highlights the vulnerability factors such as climate
change, population growth, economic development, and management, etc. of
freshwater resource vulnerability. Currently, this method has been used to assess the
vulnerability of water resources in the Pacific Islands, West Asia Region, and
South Asia and some river basin as Mekong river basin, Amu Darya river basin,etc.
The research on sea environmental resource vulnerability assessment in
Vietnam has just begun in the late twentieth century. To date, there are many studies
following different approaches, such as regions/areas, natural systems and social,
community, resources in different areas. The study is based on general principles of
a vulnerability assessment is to determine the ability of a compromised system
(natural, social and economic) to meet natural disasters and man-made, one
determine the resilience and recovery of systems; thereby, proposing vulnerability
mitigation measures. From 2001, the team of Prof. Dr. Mai Trong Nhuan conducted
studies assessing coastal vulnerability (Mai Trong Nhuan 2005). Thereby, the
research team has identified the ability of the vulnerable segments of society,
nature, previous works. The combined effects of natural and man-made disasters as
well as vulnerability maps propose mitigation measures for many coastal localities
11
in our country. For the method to assess the vulnerability of water resources had
initially applied research project to assess the vulnerability of water resources to
river resources as Vulnerability Assessment of Water Resources Systems in Thach
Han basin, Nhue Day basin by Trinh Minh Ngoc and others, 2013 - Faculty of
Hydro-Meteorology and Oceanography, VNU University of Science used
Methodologies Guidelines of UNEP and Peking University (Trinh Minh Ngoc
2013). However, this approach on the Island is still not applied.
For Southwestern areas, the densely populated island group also has studied.
As the evaluation of Prof. Le Duc An (1995), this area is much variation in natural
conditions, natural resources. The project "Research on natural conditions and
Southwestern areas of environmental, economic development serves to protect the
security and sovereignty " KC09 02/06-10 of Prof. Do Ngoc Quynh mentioned the
major motivating factors in the forms of sea disasters, environmental impacts of
climate change in the current trend. Overall, the southwestern areas, especially in
the island system have not been fully studied with the latest data on natural
conditions, resources and environment. In which, freshwater resources is most
vulnerable.
12
CHAPTER 3: DESCRIPTION OF THE STUDY AREA
3.1. Geography and Socioeconomics
3.1.1. Geography and Biodiversity
a) Geography
Phu Quoc, also known as Pearl Island, is the largest island of Vietnam,
located in the Thailand Gulf. The total area of the Island is 567,55 km² (National
land statistics, 2005), approximately the size of Singapore. Phu Quoc District has a
total area is 589,23 km2, perimeter about 150km, includes 2 towns and 8 communes
(NAWAPI 2010).
Duong Dong Town, located in the northwest is the administrative town of the
Island. Phu Quoc is located 120 km from Rach Gia and Ha Tien town by 45 km.
Phu Quoc Island lies in the Gulf of Thailand in Southwest of Vietnam, Phu
Quoc stretches from latitude 9°53' to 10°28' and longitude from 103°49'to 104°05'.
\
Figure 3.1: Location of Phu Quoc Island on satellite images
(Source: Google Earth)
13
b) Topography
The topography here is quite diverse, but the main type is still hilly terrain.
Topography can be divided into two areas of Phu Quoc Island with the following
characteristics (NAWAPI 2010):
- North Island has an area of about 400km2 with over 70% of mountains
(average slope of 25-30%), less than 30% of the low hills and flat land.
Overall, topography elevation is lower from the north to south and from east
to west.
- South Island has an area of about 1672km2, including many low mountains
alternating strips of land fairly low and gradually in the direction from
Northeast to Southwest with a slope less than 15%.
Currently, it is being used or capable of use for agricultural production.
Follwing are the results of the natural distribution according to altitude and slop.
Table 3.1: Distribution by altitude and degree slope
Altitude
(m)
Current status and
potential use
Slope
Area (km2)
Percentage (%)
12,17
Agriculture,
<5m
<8%
69
construction, tourism
Agriculture,
5-40m
<15%
>15%
143,8
25,36
construction, tourism
Forest, ecotourism
>40m
Total
354,2
567
62,47
100
Source: National Center for Water Resources Planning and Investigation
(NAWAPI)
c) Meteorology
Phu Quoc Island has one meteorological station was set up in 1957 in Duong
Dong town, observation of meteorological factors: temperature, humidity,
evaporation, wind, sun, and rain. Until 1995 on Phu Quoc island has two water
levels stations at White bridge locations on Cua Can river and at Tram station on
14
Duong Dong river. Oceanographic stations are located in the estuarine areas of
Duong Dong.
The specific datas on temperature, humidity, wind, etc of Phu Quoac
were provided by Kien Giang Hydrometeorology Center.
Phu Quoc Island area characterized by tropical monsoon climate. High
temperatures during the year, an average of 27.10C. Evaporation (Piche) annual
average is 1,210 mm (3.3 mm / day). Average annual humidity is 82.6%. October,
the highest average humidity (87.8%). February, the average humidity is lowest
(75.5%) (NAWAPI 2010).
Annual rainfall is abundant here, annual average 2902 mm and is relatively
stable over the years (coefficients of variation Cv = 0.176) (NAWAPI 2010), pretty
standard distribution. Rainfall in large stable with mountainous terrain conditions
are ideal conditions for the development, management and operation of small and
medium reservoirs on the island of Phu Quoc.
15
0
Table 3.2: Temperature characteristics ( C) at Phu Quoc Station (1984-2011)
Characteristics
Average
I
II
III
IV
V
VI
VII
27.7
34.4
21.7
VIII
27.6
33.8
21.8
IX
X
XI
XII
26.4
33.8
17.6
Year
27.4
37.0
17.3
26.1
34.3
17.3
26.7
34.3
17.1
27.8
35.8
18.5
28.6
35.8
22.0
28.6
37.0
22.1
28.2
35.5
22.5
27.2
33.8
22.1
26.9
33.7
21.4
27.0
33.3
19.9
Highest
Lowest
Average lowest
Average highest
30.7
23.3
31.3
23.9
31.0
24.1
32.6
25.7
31.6
25.9
30.6
25.7
30.0
25.3
29.7
25.3
29.5
25.1
30.3
24.7
30.7
24.6
30.5
23.8
30.7
24.8
Table 3.3: Average humidity by months – year (%)
Month
I
II
III
79
75
77
IV
79
78
80
V
VI
VII
86
VIII
87
IX
X
XI
83
81
79
XII
79
Year
83
Tho Chu
Rach Gia
Phu Quoc
79
79
74
79
78
77
83
82
83
85
84
85
87
85
87
87
84
86
85
85
79
81
86
87
73
81
(Source: Kien Giang Hydrometeorology Center)
16
Table 3.4. Lowest humidity by months – year (%)
Month
Tho Chu
Rach Gia
Phu Quoc
I
II
III
53
39
35
IV
56
37
42
V
VI
60
55
58
VII
64
VIII
64
IX
58
56
55
X
XI
61
50
41
XII
57
Year
48
54
49
34
48
47
33
55
48
41
65
50
50
60
57
50
37
56
49
35
33
(Source: Kien Giang Hydrometeorology Center)
Table 3.5: Characteristics of rain in Phu Quoc
Month
I
II
III
IV
V
VI
VII
VIII
IX
X
XI
XII
Year
Highest rainfall
per day
mm 77.9 112.2 103.2 127.1 109.6 126.8 196.5 327.1 188.4 181.2 136 105.4 327.1
Average
monthly
mm
32
28
66
154
12
260
19
365
21
390
22
474
24
458
23
355
21
145
13
52
6
277.9
177
rainfall
Average rainy
days
date 6
4
7
(Source: Kien Giang Hydrometeorology Cent
17
Analysis of rainfall data from Phu Quoc stations for the period from 1985 to
2011 shows that total annual rainfall has decreased by an average of 19.8 mm /year
(Nguyen Ngoc Tran 2013).
Figure 3.2: Total annual rainfall in Phu Quoc station (1985 – 2011)
(Source: Kien Giang Hydrometeorology Cente)
Water level data from Phu Quoc station shows the maximum tide height,
minimum tide height and the average trend line for the period (1988 - 2010);
annual average tidal amplitude and the average trend line in the years (1988 -
2009) are shown in the image below:
Figure 3.3: Hmax, Hmin in Phu Quoc island
(Source: Kien Giang Hydrometeorology Center)
18
Figure 3.4: Tidal amplitude in Phu Quoc island
(Source: Kien Giang Hydrometeorology Center)
Tidal amplitude has the trend increased both on tidal and tidal foot. The
maximum tide height, minimum tide height for the period (1988 – 2010) tend to
increased.
Based on the standards division of the rainy season and dry season
Hydrometeorology Center (monthly rainfall exceeding 150 mm, surpassing the
average evaporation month period, the fall in the rainy season) and in combination
with the analysis of Duong Dong station rainfall data, rainfall regimes in Phu Quoc
island can be divided into the following two seasons: rainy season lasts 7 months
(May - November), coincided with the period of active southwest monsoon; 5
month long dry season (December- April years later), coinciding with the period of
operation of the northeast monsoon. April rainfall average is 150 mm at Duong
Dong station, but heavy rain and steady rainfall in the last 10 days of April, so April
could be considered a transition month from dry season to the rainy season. The
rainy season accounts for 81% of total rainfall leading to excess water during the
rainy season, water shortages in the dry season. Moreover, due to the steep
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