Assessing the Main Causes of Flood Hazard through Examining Gis and Rs Based Land Use Land Cover (Lulc) Change, Topography (Slope) and Drainage Density Analysis in Alamata Woreda, Southern Tigray Zone, Ethiopia Mr. Kassa Belay Abera Lecturer, Department of Geography and Environmental Studies, College of Social Sciences and Humanities, University of Gondar, Ethiopia Online published on 5 July, 2014. Abstract Floods are common natural disaster occurring in most parts of the world and also are the key environmental problems in degraded watersheds. This study was conducted in Alamata woreda watershed in southern zone of Tigray region where there is high incidences of floods. The objectives of this study are to investigate the main (root) causes of flood hazard in the study area. The spatial analysis like LULC change, drainage density and topographic (slope) analysis was conducted with ERDAS, RS and GIS. The remaining non-spatial data of flood cause analysis and assessment was done based on the data collection and concept from the literature review. These, data was gathered through observation, interviews with different officers from different government and non-governmental organizations and a simple random sampling and purposive sampling techniques used to collect the data through questionnaire survey given to 392 HHs of flood victim areas of Alamata Woreda. Results of questioner from household respondents, interviews with government and NGOs and direct observations in Alamata woreda indicate that flood hazard is increasing due to major factors like land use/land cover change, rain fall pattern, slope and drainage densities. Result from ERDAS, GIS and RS analysis show that the study watershed is experiencing with high LULC change and dynamics on agricultural, settlements and bare lands and those change aggravated the peak flow or reoccurrences of flood hazard in the study area. The finding in the study area clearly shows that, land use and land cover change has highly correlated with flooding because theses impacts and occurrences of flooding in the study watershed was occurred after a few years i.e. after forest and grazing lands has changed to bare lands, settlements and agricultural lands. But unquestionable fact in relation to land use land cover change in the study area the degree of flooding or runoff is closely related to and is a reflection of the degree of rainfall, topography and drainage density. Top Keywords Flood Hazard, Land Use and Land Cover Changes, Assess through GIS & RS. Top |