ITOGA Rei Shinshu University College of Agriculture, Prof., 農学部, 教授 (40114037)
ITO Taichi University of Tsukuba, Inst.of Agr.and Forest Eng., Assit.Prof., 農林工学系, 講師 (40175203)
SATO Shun University of Tsukuba, Inst.of History and Anthropdogy Prof., 人類学系, 教授 (00114497)
AMADA Takaaki University of Tsukuba, Inst.of Agr.and Forest Eng., Prof., 農林工学系, 教授 (80114031)
|Budget Amount *help
¥4,600,000 (Direct Cost: ¥4,600,000)
Fiscal Year 1995: ¥800,000 (Direct Cost: ¥800,000)
Fiscal Year 1994: ¥900,000 (Direct Cost: ¥900,000)
Fiscal Year 1993: ¥2,900,000 (Direct Cost: ¥2,900,000)
On the west side of Mt.Hakusan (2,702 m), Ishikawa, used to be located are isolated farm houses and lands called "Dezukuri", which literally means farming away from the village (permanently or seasonally). They are usually located on the hillslope, with some on river terraces. They have employed a special system of farming based on slash and burn with crop rotations, adopted to their harsh natural environment. During the 1950s when the energy revolution and high economic growth rates started in Japan, one of their basic economy collapsed (reduced demands in charcoal : cash products). Consequently, since then a lot of farmers have abandoned their lands and permanently moved into neighboring cities.
The purpose of this study is with the overlay method to analyze, utilizing a geographic information system (GIS), the natural environment of the Dezukuris distributed in Shiramine Village. A distribution map of the Dezukuris was produced from 1 : 5000 map on which spot locations of Dezukuris were indicated and from aerial photointerpretation, resulting in 322 dezukuris with a total area of 1.39 km^2. The map was subsequently digitized and overlaid with the environmental data including elevation, slope aspect, slope gradient, drainage network, earth-flow distribution, geology, soil, natural vegetation, silvioulture and logging road map. The environment where a large number of the Dezukuris used to be located is found to be, 1) slope gradient 10-25ﾟ, 2) slope aspect, northeast-southeast, 3) elevation, 600-900 m, 4) geology, conglomerate-shal, 5) soil, wet forest brown, 6) vegetation, beech stands in general, and 7) proximity to water and logging roads. Since slow-moving landslides (earth flow) have produced gentler slopes on the hillslope, quite a few Dezukuris were located on these slopes. It appears that topographic factors were more important than vegetation and geology/soil in this area.