The main steps and operations that we followed are:
a. Identification of potential hazards and of elements at risk from the study area,
b. The evaluation of the natural risk factors through the application of the two mentioned methods (the questionnaire and AHP), and
c. The assessment of factor importance to area level of vulnerability by consistency analysis.
Identification of potential hazards: Field studies and investigations among the local population allowed the identification of the types of potential hazards present in the studied region: - tidal surge and their height, speed; relationship between storm wind, cyclone and tidal surge and changing pattern due to the change of global climate; - flash floods and flood, favored by the climatic conditions, hydrologic regime of rivers (with significant seasonal variations) and the morphology of riverbeds, with direct implications on the riverbed processes’ manifestation; - river bank erosion, especially active river bank mudslides, also with great activation potential, tillage methods of the population near the river bank and often intensified by the anthropogenic factor; -storm wind, wind force, force direction, season of storm wind, relationship with cyclone and wind storm -uncontrolled anthropogenic interventions, especially over activities on bank slopes and constructions in close proximity to rivers, contributing to the acceleration of risk phenomena. -degradation of land quality; land cover, forestation or deforestation along the river. The evaluation of natural and anthropogenic risks and their role on peoples life following the questionnaire and the Analytic Hierarchy Process methods allow indicating the quantity of exposure to hazards and the assessment of significant weight and hierarchy of the risk factors’ in the measure of vulnerability in a victim community. In the present research, the two methods have been applied in analyzing quantity of exposure to hazards and the assessment of significant weight of the risk factors’ of the population living at the area of Angaria and Lebukhali union of Dumki Upazila of Patuakhali district along with
The evaluation of the natural risk factors through the application of the questionnaire and AHP methods: Perception is the individual and private mental process of organizing all the received external impulses (Armas, 2008), which, in risk analysis, requires a high degree of unpredictable decisions, often subjective towards given realities.
Questionnaire method: We have designed a questionnaire containing 2 (two) questions and seeking answer of awareness likelihood through these two questions. It was aimed at assessing understanding/perception (clear or unclear), the exposure degree (involuntary-voluntary), the GO/NGO institutional efforts (absent-involved), awareness of Risk Reduction Action Plan (RRAP) (yes, no) and the degree of personal participation/involvement (high, low). Four potentially destructive phenomena were chosen: river bank erosion, tidal surge, flash flood and flood and finally, a fifth open question to which many people mentioned a risk of hazard, which may be natural or man made; a sign that this issue is a matter of concern for the people of the area.