Rainfall and Landslide Susceptibility in Hakha Environ in Northern Chin State, Myanmar

Abstract

This research emphasizes the cause of landslides that occur in Hakha Town and its environ. The main aim is to investigate the distinct phenomena that result in a landslide and to provide suggestions that can reduce the risk of landslide in its prone area. Regarding the two phenomena, natural and man-made, the data on soil, steep slope, monsoon rainfall, pine forest areas, water sources, motor-car road area, population, and houses were collected by field survey, observation, and questionnaires. The collected data were processed and analyzed by using remote sensing methods, qualitative and quantitative methods, and Geographic Information System. According to the results, major causes of the landslides in the study area are found to be due to location lying between 1,830 meters (6,000 ft) and 2,440 meters (8,000 ft) above sea level and establishing of the settlements on steep slopes, receiving plenty of rainfall under the mountain climate with the extremely cold winter season, the existence of unstable and unconsolidated soil and lithology, extending construction of new roads and expansion of the existing roads, population growth and settling of more people in the urban area, and collapsing of big old pine trees. In conclusion, landslides in the study area are found resulting from combined activities of physical factors and human impacts.