Analysis of material supply characteristics of debris flow based on land use types in the upper Min River, China

Abstract

Land-use type is a natural choice of human social and economic activities. This study investigates the typical debris flow gullies of the upper Min River and analyses the supply characteristics and activity of its material sources under various land-use types using multi-stage remote sensing images data and geographic information system software. The results demonstrate the following: (1) the land-use type does not restrict the loose material source of debris flow near the fault zone; (2) the degree of cultivated land, forest (grass) land, bare land, and urban and rural construction land promote debris flow disaster formation in different channels far from the fault zone; (3) the gully exhibits significant influence on human engineering activities, and there are more loose material sources between the bare land and urban and rural construction land; (4) more loose material sources are observed in forest (grass) land and cultivated land in debris flow channels with vegetation development. In summary, before the Wenchuan earthquake, the debris flow source centroid is far from the debris flow channel, but after the earthquake, the debris flow material source centroid is near the debris flow channel.