北海道・猿払におけるポドゾル性土壌の粘土鉱物について

概要

論文の詳細を見る
Clay mineral composition of a podzolic soil in Sarufutsu was investigated by X-ray diffraction and chemical analyses. In all horizons of the soil, dioctahedral 2: 1 layer silicate minerals were dominant in clay fractions. Montmorillonite-like expanding mineral was found in A_2 horizons (bleached horizon). Also in A_1 and B_<21> horizon, a part of minerals was expansible. The lower the horizon, the more broad was the basal spacing of the K-saturated 2 : 1 minerals and the more stable against contraction to 10 A by heating. Minerals of 1 : 1 type were also detected in smaller amount, with increasing amounts with depth. Quartz was found in the clay fractions through all the horizons and was especially rich in upper horizons. From the facts aforementioned, it may be concluded that under the influence of specific chelating action of organic acids, such as fluvic acid, aluminium in interlayers is leached out, and consequently vermiculite is transformed into expanding minerals in A_2 horizon. Expanding minerals in Al horizon are formed presumably through similar process as in A_2 horizon, while the presence of such minerals in B_<21> horizon may be attributed to the movement and accumulation from upper horizons. It seems that the aluminium which held between layers increases with depth and vermiculite changes gradually to Al-vermiculite.
日本ペドロジー学会の論文
1966-06-30