Multi-natural hazard assessment of Bursa using the GIS method

Many parts of the world are affected by more than one natural hazard. Effective risk reduction is possible if all hazards are considered and analyzed together. Multi-natural hazard analysis is the process of assessing several hazards that occur in a given area by taking them all into account. The first and most important step in risk reduction planning is the creation of hazard maps. The goal of this study was to use the Geographic Information Systems (GIS) method to create and analyze a multi-natural hazard map of natural disasters including earthquakes, mass movements (landslides, rock falls), floods and overflows, forest fires and avalanches in Bursa province, located in the southeast of the Marmara Region of Turkey. In this regard, first of all, the general geographical features of Bursa were discussed in order to describe the study area and to use the features in multi-natural hazard analysis. Next, the spatial and temporal distribution of hazards on the basis of districts and neighborhoods was discussed in accordance with the inventory obtained for each hazard, and a number of past hazards were presented as examples. Hazards were combined and treated in an integrated manner, their spatial and temporal distribution was examined, and a multi-natural hazard density map was created and interpreted by creating and overlaying the intensity map for each hazard. Finally, the relationships between geographical factors and the integrated hazards were analyzed. The multi-natural hazard density map of Bursa that resulted from the study showed that the highly hazardous areas were located where the Bursa and Inegol plains intersected with the Uludag slopes, particularly in the northwest, north, northeast, and east of Uludag. These are areas with a large altitude difference, as well as areas where altitude, temperature, and precipitation values change dramatically over a short distance. The fact that the high-hazard areas are within the borders of the districts with the highest population in the province supports the importance of the study.