40 exemplified in the district of Pundong, Imogiri, Pleret, Piyungan, and
Banguntapan. •
The second cause of a decreased level of ground stability is influenced by factors of slope, where the steep increase disaster factor. Slope factor as stated in earlier
studies may lead to further disasters in the form of landslides or rock avalanches. Imogiri are examples of areas with steep slopes that have a low degree of ground
stability or in general in the east of Bantul Regency. •
The prevalence of deaths, injuries, and destruction of buildings at all levels of ground stability possible existence of high vulnerability factor, especially in areas
categorized as having high stability factor, for example in District of Sewon and Kasihan. Assessment of the level of disaster related to the fact the number of
casualties and damage requires understanding the concept of vulnerability. •
The resulting map is still too general as this disaster database because there is still no availability of data in detail scale. Possible differences in accuracy also
led to a general outcome. •
Determination of criteria for disaster needs further study include the use of scoring and weighting that may only be applied in the study area.
• Involving local communities in the field survey and supported the GPS device is
helpful in assessing the accuracy of maps of disaster.
2.6.2 Recommendation
Some recommendations for further investigation are related to hazard analysis: 1. It is necessary to scale geological map in more detail to improve the accuracy of
disaster prone areas. 2. Necessary to identify early on the impact of further disasters like landslides due
to earthquake such as landslide, ground rapture, and liquefaction.
41
CHAPTER III
Vulnerability Analysis in Urban Area Related Earthquake Hazard
3.1 Introduction
Increasing growth population followed by physical development in built up area will increase susceptibility and probability earthquake impact in urban area. The
centralization activities in urban area can trigger urbanization which shows in migration phenomena. Rapid urbanization in the world cause 50 percent population
will dwelling in the cities, and expected to be absorbed by the urban areas of less developed regions UNEP, 2007.
The importance to identify the vulnerability factor in urban area will protect people, before the hazard occurrence, and prepare precaution for them Haki,
2004. The impact history of earthquake in urban caused the damage of the life system and
espeacially caused many casualities. The experiences about impact of earthquake in urban area are the occurences in NAD 2004, BantulCSpecial Region of Yogya
2006, Tasikmalaya 2009, and Padang 2009. The damage of life system is related to vulnerability factors such as physical, socioCeconomic, demographic, and etc.
The analysis processes of vulnerability were classified in several factors such as physical, demographic, and social. Physical factors in terms of disaster were
associated with everything built by humans. Demographic factors associated with resident population of an area where increasing population and the intensity in a
region highly affected, while social factors were closely related to the ability of the community in case of disaster. Vulnerability factors is vast and varied for a given
region, the selection of vulnerability factors depend on the characteristics of the study area, the accuracy of the model built, and the availability of supporting data.
42 GIS has the capacity to perform spatial simulation by combining multiple layers of
spatial information. By leveraging the advantages of GIS, it is possible that vulnerability is made to be maps that combine the spatial distribution of physical,
demographic, and social factors.
3.2 Objective of Research
The objective of research is to determine vulnerability area based on physical, demographic and social factors using multiCcriteria analysis, and simulation in GIS.
3.3 Literature Review
Vulnerability is characteristics and circumstances of a community, system or asset that make it susceptible to the damaging effects of a hazard ISDR, 2009. It is
important to understand about level of vulnerability which is vulnerability influenced by strength disaster factor, because disaster will occur in the vulnerable situation
BNPB, 2007. Level of vulnerability can be considered into 3 three types:
1. Physical Vulnerability; relating to vulnerability for regional infrastructure like
density of building, percentage of built up area, percentage of building, emergency construction, road network, communication network, and etc.
2. Social Vulnerability describing about level of social fragility to facing hazard.
Several indicators for social vulnerability are density of population, growth rate population, and gender female percentage.
3. Economic Vulnerability describing about level of economic fragility to facing
hazard. Some indicators for economic vulnerability are poor household and worker.
Comprehension about vulnerability is very various meaning depend on scientific groups Taubenbock, 2008, and the discussion is still continue and did not reach
precisely Birdman, 2006a in Taubenbock, . 2008. Refer to Taubenbock
2008; vulnerability is not only in physical, social, and economic factors, but also
