A Study on the Extraction of Multi-factor Influencing Floods from Rs Image and Gis Data; a Case Study in Nackdong Basin, S.korea

The climate changes will be much more significant over the next 100 years and may lead to the heavy rainfall event. The heavy rainfall causes the flood hazard in the lowlands and geologic hazard in the mountains. Floods are also related to the changes in social economic conditions and land use. Recently, floods have been increasing due to rapid urbanization and human activity in the lowlands. Therefore, integrated management of total basin system is an essential part of secure society. In case, the Nakdong basin is the second largest basin in S.Korea and surrounded by mountain ranges. The reasons of floods are caused by overflows and collapses of the banks in the Nakdong basin. The purpose of this study is to extract the multi-factor related to flood hazard concerning geomorphologic characteristics, land cover, and runoff régime. For the multiple criteria valuation technique, we choose multiple factors and determined their relations and how they impact the flooding areas. Two important concepts on the geomorphologic effectiveness of a watershed are the geomorphologic characters and interactions of water routing. As a result, the vulnerability map and the flood-prone areas can be extracted by applying spatial analysis on geographical information system(GIS) and image data(SRTM and Landsat TM). * Corresponding author. Tel.: +81 43 29