A Study on Land Use at Landslides in the Eastern Chugoku District and its Environs

Abstract

Land use are one of the remarkable indicator of the ground water condition and landslide activity. For example, rice field and cryptomeria grove are often assumed to be a sign for wet soil condition i. e. high ground water level, and it makes soil strength lower. Therefore, this kind of muggy area is apt to provide landslides, and vice-versa. On this point of view, land use has been studied as one of important factor to distinguish landslide prone area from other safer one in the remote sensing methods.In this study, land use characteristics in eastern Chugoku district including northern Hyogo, Tottori, and northern Okayama prefecture are studied in terms of relative frequency “S” to each land use type. Here, S=NiL/Ni and NiL: land use frequency on landslides, Ni: land use frequency in the area investigated. The results of this study imply orchard or dry field as well as residential area is prominent in land use on landslides.Rice field is only third in it, and oak wood which appears rather dry land than cryptomeria is remarkable.Hence, it is not insisted that all land use feature on landslide in the area studied is related to the wet soil condition. It is important to consider about this results when landslide assessment is carried out in this area with a kind of remote sensing method.