早池峯山麓ヒバ林下のポドゾル化土壌の粘土鉱物
1974 年 18 巻 1 号 p. 11-22
詳細
1974 年 18 巻 1 号 p. 11-22
A podzolized soil develops under the forest of Hiba (Thujopsis dolabrata) growing at the foot of Mt. Hayachine in Iwate Prefecture, Tohoku provinces. The soil is located at about 800 meters above sea level, and has been classified into P_D II-P_W II by YAMAYA (1973). Mineral composition of the clay fraction, less than 2 microns, in the podzolized soil was examined by chemical analysis, X-ray diffraction method, thermal analyses, infrared absorption spectroscopy and electron microscopy. The results is summarized in following table : [table] The amount of quartz was maximum in A_<21>-horizon and minimum in B_2-horizon, and α-cristobalite was decreased as the horizon was deepened. Gibbsite was most abundant in B_3-horizon, and poor amount of that was also detected in the horizons above B_1. The amount of hydrous iron oxides was maximum in B_1-horizon and minimum in A_<21>-horizon.
