Nepal is similar to Japan on climatological and topographical aspects. However, Nepal has the tropical area in the southern parts. In this report, vertical distribution of forest soil was compared with that in Japan. Observations in the report are limited in the farmost western area in Nepal. Five forest soil groups were observed in the surveying area from tropical to temperate zone. Three of them belong to the zonal soil groups and the other two the intra-zonal. Four groups of them were morphologically, chemically and physically determined. These soils include the gray-yellowish brown forest soil under the tropical hill forests, the yellowish brown forest soil under the sub-tropical ever green oak (laurel-leaved) and pine forests and the brown forest soil under the deciduous forests as the zonal soil groups, the surface gleyed soil with the black surface as a intra-zonal soil group. In addition, the dark red earth, probably derived from the basic schist, was recognized in Middle Hills, although analyses have not been conducted. Dominant properties of zonal soil are as follows: 1. Soil color of A horizon gradually changes from grayish yellow in the tropical zone, through yellowish brown in the sub-tropical to dark brown in the temperate zone. 2. With an increase in the elevation, A_0 horizon (L layer) thickens and is morphologically transformed to litter and fermentation layer (LF layer). 3. Soil organic carbon contents of A horizon also increased with the elevation, ca. 2% in the tropical and sub-tropical to ca. 5% or more in the temperate zone. The green fraction of humic acids increased as well as the carbon contents, especially in B horizon. 4. The base saturation degree decreased with the increase in the elevation. 5. Major alumino-silicate clay minerals are Al-vermiculite with the small amounts of chlorite, kaolinite and mica. The dominant properties of the black gleyed soil are extremely high C/N ratio and its mojor clay minerals consist of meta-halloycite. Although the situations mentioned above may not be present in Japan, several Japanese pedologists have suggested that (red-) yellowish brown forest soil may occur under the laurel-leaved forest of temperate area in Japan. The authors also support the existence of the soil in Japan from the results in this report.
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