Pedologist

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There are unusual occurrences of reddish coloured soils on the upland along the coastal region of the Okhotsk Sea. The topography of the region is consist of three terraces named T_1, T_2 and T_3 from higher towards lower and of gentle slopes or erosion surfaces extending to mountainous region behind the highest terrace (T_1). These terraces may be distinguished from each other by means of relative height, stratigraphy and degree of dissection. It seems to be very important that the most of reddish coloured soils distribute on the gentle slope, and some of them on the highest terrace (T_1), but never on lower terraces (T_2 and T_1). Furthermore, it is also notable that there is no definite causal connection between reddish colour of soils and their parent materials. In these reddish soil profiles, following common morphological characteristics are observed. General horizon sequence may be shown as A_0/A_1/ A_3/B_1/B_2/C_1/C_2. The morphology of the upper part of the profile (above B_1 horizon) seems to closely resemble that of Acid brown earth commonly developed in this region. On the other hand, the lower part (below B_2 horizon) is characterized by distinct reddish colour (10R-5YR in MUNSELL'S notation), heavy texture, well developed blocky structure, as well as compact, plastic and sticky constitution. In the C horizon occasionally a sort of reticulated pattern is observed. These features seem to give marked coinsidence with those of subsoil in, zonal Red soils in humid subtropical zone. It was be quite reasonable to assume that the lower part of the reddish soil profile should be a "relic" of Red soils or weathering crust of them which could be formed under much warmer climatic conditions during a given geological age, perhaps in Riss/Wurm Interglacial, judging from stratigraphical, geomorphological and soil morphological evidences, as well as the geographical or latitudinal situation of this region. To the contrary, the upper part of the profile may be inclined to develop Acid brown earth under recent humid cool-temperate bio-climatic circumstances.

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Almost of New England is covered with so-called wind blown materials which are recognized as the matter piled in gracial age. The thickness of these materials is from 60 to 75 cm, and the mineralogical constituents are garnet, augite, chlorite, muscovite, quartz and so on. The author took the sample at the hill-side near Amherst Mass., the profile is as description. This place is covered by deciduous trees as Oak, Sweet birch, American chestnut, Hickory, etc. The climatic conditions are pointed as Table 1. The particle size distribution of each horizon is similar from the top layer to the 5th layer. These layers are pointed as wind blown soil and the soils are classified as sandy loam (U.S. Method). The SiO_2/Al_2O_3 and the Base/Al_2O_3 ratios are about 9 and 1 respectively through the top to the 5th layers. The soil reactions are very acidic. The clay minerals separated from these samples show the containing of chloritic minerals like sheridanite, penninite and illite. By the reason of the coarse texture, the cation exchange capacity is very small, though in the humus layer it reaches to 10me/100g. This soil is concluded to belong to the Sols bruns acides as great soil group.

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