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

doi:10.34104/bjah.02201014

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.

Highlights

This research paper analyzes the effect of 2015 landslide that occurred in Hakha due to heavy torrential rain followed by mudflow resulting in erosion, falling down of large trees, and collapsing of buildings and human settlements (Sekhar et al, 2008)
The landslide was derived from combined activities of urbanization, overproducing of forest products, and mainly heavy rain that prevailed within 4-5 days continuously
The landslide mentioned above was found related to the geological structure of the Hakha area which is formed of folds, joints, and local faults because the earth slid according to the dip orientation of the rocks

Summary

Introduction

This research paper analyzes the effect of 2015 landslide that occurred in Hakha due to heavy torrential rain followed by mudflow resulting in erosion, falling down of large trees, and collapsing of buildings and human settlements (Sekhar et al, 2008). From a geographical point of view, those that have caused landslide events in Hakha are found to be physical factors and human factors. The former includes presence of (1) steep slopes susceptible to erosion, (2) soil creep and debris flow, (3) joints in parent material rock, (5) seepage of groundwater due to increasing pore water pressure, (4) lying in the intermountain valley and (6) occurrence of. Naing et al, / British Journal of Arts and Humanities, 4(1), 01-14, 2022 heavy rainfall (Sekhar et al, 2008) The latter factors are those of the reclamation of shifting farms locally known as Taungya, the establishment of human settlements, and the construction of roads, ditches, and urban infrastructure (Tiziano Tempesta, 2010)

Results

Discussion

Conclusion