Soil fertility under various land use types in a village in Mae Taeng District, Chiang Mai Province in northern Thailand was investigated based on soil physicochemical properties. The land use changed toposequentially with altitude; residences with home gardens, perennial cash crop orchards (lychee and orange) and teak plantations were located on relatively flat lands at the bottom of the valley, while banana stands and bamboo-mixed secondary forests were on steep slopes of the mountainsides. Remnant forests remained only around the ridges. Soils were relatively sandy in texture and were almost neutral to slightly acidic in reaction. Exchangeable cations were predominated by Ca and Mg with a low level of Al saturation. The level of available P was low. It was revealed that soil organic matter played important roles for CEC and physical properties both in the surface and subsurface layers. In terms of land use types, the levels of total C and total N were lower in the farmlands and teak plantations than in remnant forests and bamboo stands. It is indicated that the reduction in soil organic matter could not be avoided by farming practices, even under lychee orchards and teak plantations where abundant leaf litter was supplied to soil surface. The soils under bamboo and banana stands showed relatively high pH values and high contents of exchangeable bases, of which levels were similar to or even exceeded those in lychee and orange orchards with fertilizer application. This could be ascribed to repeating fire occurrence as well as the addition of nutrient rich surface soils from upper slopes. In the lychee and orange orchards, the nutrient levels at the fertilizer-applied points under the tree canopy were mostly similar to or lower than those in-between the trees, except for available P, indicating nutrients added to the soil surface seemed to be leached downward by plentiful water supply with sprinkler systems unless taken up by plants.

Extensive surveys on distribution patterns of soils and landscape were carried out in the foothills and mountain slopes of the Tienshan and Altai Mountains. Clear trends were observed for the distribution in terms of vertical zonation as well as west-to-east transition. In the Tienshan Mountains, soils at higher elevation were affected mainly by increasing precipitation and hence had lower pH and higher content of organic matter. For example, in the northern foothills of the Tienshans next to the China-Kazakh border (Ketmen Range), Calcisols were distributed in the lowermost regions (below 1,300 m), and afterwards Kastanozems (1,300–1,550 m), Chernozems (1,550–1,800 m), Phaeozems (1,800–2,400 m), and Umbrisols (above 2,400 m) were found with an increase in elevation. Chernozems, Phaeozems, and Umbrisols were often covered with broad-leaved or Picea forest typically on the northern slopes. Such a vertical zonation of soils was commonly observed in the remaining six sub-regions surveyed in both Tienshan and Altai Mountains, but all the borders between desert and steppe, steppe and forest zones, and deciduous broad-leaved and coniferous forests shifted to higher elevations due to wet to dry climatic transition from west to east in either Tienshan or Altai Mountains. The difference among the slopes between elevation and surface soil pH in each of the sub-regions was consistent with the transition of landscapes described above. Then using equations derived from secondary datasets from established meteorological stations, relationships between climatic conditions and distribution patterns of soils and landscape are described.

A historical examination of the usage of Japanese terms of “Tsuchi” and “Dojyo” made it clear that “Tsuchi” corresponds to soil material. While, “Dojyo” has been mainly used since the middle of 19th century as the translation of the Dutch “bodem”, the German “Boden” or the English “soil”. Therefore, it is appropriate to use “Dojyo” limitedly in the meaning of soil as a natural body. To make the Japanese citizen understand the importance of soil, it is necessary for the Japanese pedologists to consciously use the terms “Dojyo” and “Tsuchi” in the separate meanings as mentioned above.