Abstract
Microtopography, vegetation, structure of subsoil and amount of soil erosion were observed in order to know the relationship between microtopography and plants, namely their distribution and species composition of communities. In the study area, ca. 100 m×150 m in size, a probe area of 30 m×50 m was set. The probe area was separated into 60 quadrates of 5 m×5 m. Quadrates were divided into three groups (1), (2) and (3) according to species composition. Groups (1) and (2) have the species found commonly in beech forests. Among them, group (1) is characterized by the species of beech (Fagus crenata) forests under dry condition and is found on the crest slopes and upper landslide scarp where deposition of soil materials is not expected. Group (3), characterized by the species of Pterocarya rhoifolia forest are observed in the lower part of landslide body under depositional and humid soil condition induced by the groundwater seepage at the toe of a landslide body. Group (2), with no remarkable characteristic species, basically composed of the species of beech forests, are located on the various micro-topographical units.
Vegetation of the study area is basically a beech forest from viewpoint of species composition. Species of dry type beech forest are found on the crest and upper landslide scarp. On the contrary, species characteristic to Pterocarya rhoifolia forest are found under the depositional and humid soil condition.
