Thạc Sĩ Landslide hazard and risk assessment for road network using RS and GIS- A case study of Xin Man dist

LUẬN VĂN THẠC SỸ
NĂM 2014


iii
ABSTRACT

Xin Man district in the South west Ha Giang has high landslide hazard. However, the
available information on landslide in Xin Man district is still limited. We constructed the
essential spatial database of landslides using GIS techniques. The quantitative relationships
between landslides and factor s affecting landslides are established by the Certainty Factor
(CF). The affecting factors such as slope, elevation, landcover, geology, road distance,
lineament distance, drainage density are recognized. By applying CF value integration and
landslide zonation, the most significant affecting factors are selected.
By using RS&GIS technology landslide occurrences on all these factors have been analyzed.
The vector based GIS has been used for digitizing to produce thematic maps, as analysis for
study was based on the pixel based information therefore Raster based GIS has been used for
the analysis.
Pixel based calculation was made by using the CF value Model. By using the CF model we
obtain the CF value for all classes al all factor maps. On the basis of these CF value all factor
maps are recoded and matrix analysis was perform to produce a Landslide Hazard Zonation
map.
The Landslide Hazard Zonation map has been applied to develop a methodology to produce
hazard maps considering the behavior of landslide and to evaluate potential damage to
infrastructure specific road system. Different factors have been considered for this study. iv
TABLE OF CONTENTS

CHAPTER TITLE PAGE

Title page i
ACKNOWLEDGEMENT ii
ABSTRACT iii
TABLE OF CONTENTS iv
LIST OF TABLES vi
LIST OF FIGURES vii
LIST OF MAPS ix
LIST OF ABBREVIATIONS x


1 INTRODUCTION 1
1.1 Background 1
1.2 Statement of problem 1
1.3 Objectives 2
1.4 Scope and limitation 2

2 LITERARUTE REVIEW 3
2.1 Hazard, risk & vulnerability 3
2.2 Landslide Hazard mapping 4
2.3 Fundamental of Remote sensing 5
2.4 GIS overview 12
2.5 Global Positioning System (GPS) 12
2.6 Web Map Server 12
2.7 Landslide Studies 15

3 DESCRIPTION OF THE STUDY AREA 18
3.1 Area and situation 18
3.2 Climate 18
3.3 Rainfall 18
3.4 Population 18
3.5 Geology 20
3.6 Elevation 22
3.7 Slope 24
3.8 Lineament 25
3.9 Road system 27
3.10 Drainage density 29
3.11 Landcover 30

4 METHODOLOGY AND ANALYSIS 33
4.1 General 33
4.2 Compilation of Required data 33
4.3 Field Survey by using GPS 34
4.4 Extraction of maps from the source data 35 v
TABLE OF CONTENTS (CONT.)

CHAPTER TITLE PAGE


4.5 Methodology and Analysis Data 38
4.6 Data Entry 40
4.7 Analysis data 41
4.8 Landslide Hazard Zonation Map 43

5 RESULTS AND DISCUSSIONS 44
5.1 Characterize several types of landslide in Xin Man district 44
5.2 Landslide Hazard Zonation map 46
5.3 Landslide Hazard Zonation map 54
5.4 Accuracy Check for Landslide Hazard Zonation Map 60
5.5 Develop a methodology to produce hazard maps considering the behavior of
landslides 62
5.6 Publish Landslide Hazard Zonation to Internet using Web Map Server 69

6 CONCLUSIONS AND RECOMMENDATIONS 76
6.1 Conclusions 76
6.2 Recommendation 77

APPENDICES 80
vi
LIST OF TABLES

TABLE TITLE PAGE

2.1 Landsat 7 ETM image characteristic 7
3.1 Geology, major litho-stratigraphic units with their corresponding classes 20
3.2 Area under Geology 21
3.3 Area under Elevation 22
3.4 Area under slope 24
3.5 Area under distance to lineament 26
3.6 Area under distance to road 27
3.7 Area under drainage density 29
3.8 Area under Landcover 30
4.1 Analysis data from different sources 34
4.2 Hazard zones 43
5.1 CF value of Geological 47
5.2 CF value of distance to lineament 48
5.3 CF value of slope angle 49
5.4 CF value of elevation classes 51
5.5 CF value of drainage density 52
5.6 CF value of landcover layer 53
5.7 CF value of distance to road 54
5.8 The hazard value ranges used for road buffer 55
5.9 The hazard value ranges used for whole area 55
5.10 % area for landslide hazard zone for buffer area 56
5.11 % area for landslide hazard zone for whole area 56
5.12 Defining the risk 64
5.13 Classification risk level 66
5.14 Result of the risk class based on buffer analysis 69 vii
LIST OF FIGURES

FIGURE TITLE PAGE

2.1 Criteria for risk assessment (Disaster Preparedness and Mitigation-2002) 4
2.2 Spectral reflectance of vegetation, soil and water 6
2.3 Spectral reflectance of a green left 7
2.4 The image interpretation processing 8
2.5 Data Flow in Remote sensing 9
2.6 The flow of geometric correction 10
2.7 Procedures of Classification 11
2.8 WFS Processing Request 14
2.9 Map of large Landslide areas of Vietnam 17
3.1 The yearly rainfall from 1961 to 2003 18
3.2 Location of Study area Xin Man district, Viet Nam 19
3.3 Geology chart 21
3.4 Elevation chart 23
3.5 Slope chart in Xin Man district 24
3.6 Distance to the lineament chart 26
3.7 Road area under the buffer 28
3.8 Drainage density chart 29
3.9 Landcover chart 31
4.1 Flo w Diagram For Landcover Map 35
4.2 Flow Diagram for Digitized Map 35
4.3 Flow Diagram for Landslide Map using GPS 36
4.4 Flow Diagram For TIN and maps extraction from TIN 37
4.5 Flow Diagram For Landcover Map extracted From Satellite Data 37
4.6 Flow Diagram for Buffered Road and lineament Maps 38
4.7 Methodology of thematic data layer preparation 39
5.1 Show the landslide attacked road. 44
5.2 Wedge slip occur along the road. 45
5.3 CF value of geological 48
5.4 CF value of distance to lineament 49
5.5 Statistical map of slope angle distribution in Xin Man District 50
5.6 CF value of slope angle layer 50
5.7 CF value of elevation layer 51
5.8 CF value of drainage density layer 52
5.9 CF value of landcover layer 53
5.10 CF value for distance road. 54
5.11 Bar chart showing the distribution of various hazard zones 57
for buffer area in Xin Man district 57
5.12 Bar chart showing the distribution of various hazard zones for whole area in Xin
Man district. 57
5.13 Relative distributions of various hazard zones and landslide probability within
each zone in road buffer in Xin Man district. 60
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LIST OF FIGURES

FIGURE TITLE PAGE

5.14 Relative distributions of various hazard zones and landslide probability within
each zone whole area in Xin Man district 61
5.15 The description of the road buffer 62
5.16 Show the process landslide 63
5.17 Schematization the Landslide area 63
5.18 Flow chart fo r procedure risk map 64
5.19 Minnesota Mapserver Framework Using CGI 70
5.20 Input data from the Mapfile 73
5.21 Study area on WMS 74
5.22 LHZ map in Xin Man on MapBrowser. 74
5.23 LHZ map on GMapFactory 75 ix
LIST OF MAPS

MAP TITLE PAGE

3.1 Tin in Xin Man district 19
3.2 Geological in Xin Man district 22
3.3 Elevation in Xin Man district 23
3.4 Slope in Xin Man district 25
3.5 Distance to lineament in Xin Man 27
3.6 Buffer road system in Xin Man 28
3.7 Drainage density in Xin Man 30
3.8 Landcover in Xin Man 31
3.9 Road system in Xin Man 32
5.1 Landslide distribution in Xin Man district 46
5.2 Landslide hazard zonation for buffer area in Xin Man 58
5.3 Landslide hazard zonation for buffer area in Xin Man 59
5.3 Risk of slope in Xin Man’s Road Network 65
5.4 Risk of distance to Xin Man’s road network 65
5.5 Risk in Xin Man 67
5.6 Risk assessment for road network in Xin Man 68 x
LIST OF ABBREVIATIONS

TIN Triangulated Irregular Network
DEM Digital Elevation Model
DTM Digital terrain Model
RS Remote Sensing
GIS Geographical Information System
GPS Global Position System
GML Geographical Mark Up Language
JPEG Join Photographic Experts Group
URL Uniform Resource Locator
WWW World Wide Web
WMS Web Map Service
WFS Web Feature Service 1



CHAPTER 1
INTRODUCTION
1.1 Background
Landslide has become one of the world’s major natural disasters for the few years in many
countries. Landslides are the most common natural hazard in mountainous terrain. Landslide
can be a major threat to population in the mountainous area. Even when they occur away from
the inhabited areas, landslide can be a significant hazard and have a serious economic impact
by blocking roads and river (Aniya, 1985; J. Achache, B. Fruneau and C. Delacourt 1995).
Landslides are widespread in many countries and cause great economic losses, especially
when engineering constructions are designed and erected without heeding the stability
conditions of the slopes (Q.Zaruba, V.Mencl 1967).
Landslides become a problem when they interfere with human activity. The frequency and
the magnitude of the slope failures can be increased due to human activities such as
deforestation or urban expansion.
Landslide hazard analysis is a difficult task. It requires large number of parameters and
techniques for analysis. Remote sensing and GIS are the powerful analysis tools to handle this
type of problems. A in the analysis of landslide spatial information e.g. topography, geology,
landcover, etc. are involved, therefore application of Remote sensing and GIS will be
effective.
1.2 Statement of problem
- Although landslide usually occur in Xin Man district, but people who live near or in the
landslide’s local do not illustrate the different between them. But actually, there are many
types of landslide which can occur and each of them have separate characterize. We need to
give some information to describe characterize some types of landslide in Xin Man district.
- Landslide is a serious disaster in Viet Nam. In recent 10 years, there are more than 10
areas occurred violent landslide, causing above 300 human deaths and thousands of hectares
of solids was buried by stone, sand, pebble and hundreds of inhabitant settlements having to
change their living places and locations. These are responsible for considerably greater socio-
economic loss than is generally recognized. There are some projects and research applying for
landslide but only for mid_center of Viet nam. Up to now, there is not hazard map, risk map
about landslide in Xin Man district, the leader of province only have measure to prevent
landslide every year and they have not had any project to study about landslide in the Xin Man
district. Hence, there is an urgent need to prepare landslide hazard zonation maps in the highly
landslide susceptible mountainous terrain special is Xin Man district.
- No other landslide investigation or risk assessment has been performed in Xin Man
district to date.
- Understanding and prevent landslide hazard is very important for every people. What can
people do when lack of information about natural hazard? Nowadays, internet is popular and
useful for every people. People can update, download all information and all thing which they
need to know. In this regard, we need to publish and share information about landslide on
Internet by using Web Map Sever. 2
1.3 Objectives
The general objective of this study is using Remote sensing and GIS technique to making
landslide hazard zonation mapping in Xin Man district.
The specific objectives of the study are:
1. Characterize several types of landslide in Xin Man district.
2. Create zoning maps for landslide hazard that usually occurs in Xin Man district.
3. Develop a methodology to produce hazard maps considering the behavior of
landslides
4. Publish and share landslide hazard zonation map’s information on internet using
Web Map Server.
1.4 Scope and limitation
- Landslide hazard map zonation will be focuses on critical physical factors by using GIS
overlaying thematic maps.
- To determine and localize area have high risk of landslide base on investigation, study
topology, geology, hydrology, and geomorphology.
- The limitation is associated with the availability of reliable and adequate data sets from
secondary sources to support making landslide hazard zonation map.
- Risk assessment only for road networks, not consider about the others as population,
economics, social
- Data collection is not enough to be analysis.
- Landsat TM images will be used for analysis of landcover of the study area.
- Apply existing program to publish landslide hazard zonation map on internet using Web
Map Server. CHAPTER 2
LITERARUTE REVIEW

Natural Hazard is extreme events in the earth’s ecosystem. The concepts of hazard, risk, and
vulnerability are often confused with one another and with the extreme event itself. Although
the extreme event is inherent in hazard, risk and vulnerability terminology, it is not
synonymous with the terminology. Therefore it is necessary to distinguish between the terms
hazard, risk and vulnerability.
Hazard assessment determines the type of hazardous phenomenon, frequency, magnitude and
the extent of the area that may be affected. Vulnerability indicates the degree of loss caused to
people, infrastructure, buildings, economies etc distinguishing physical (buildings,
infrastructure), functional (lifelines, communication) and social aspects (health, population
density). Risk combines the knowledge about hazard and vulnerability to make a quantitative
prediction of the elements at risk, like numbers of lives to be possibly lost, people to be
injured, cost of property being damaged and destroyed or economic activities a affected.
2.1 Hazard, risk & vulnerability
In order to provide a systematic approach to study the landslide, Varnes (1984) defined
various types of hazard, risk & vulnerability.
Natural hazard the probability of occurrence of a potentially damaging phenomenon
within a specific period of time and within a given area.
Vulnerability the degree of loss to a given element or set of elements resulting from the
occurrence of a natural phenomenon of a given magnitude.
Element at risk the population, properties, economic activities etc at risk in a given area.
Risk the expected degree of loss due to a particular natural phenomenon. Hence it is a
product of hazard and vulnerability.
Criteria for risk assessment is represented schematically as below (Figure2-1)