台灣中部中海拔－極育土中鐵瘤之微形態學

Micromorphology of Iron Nodules in a Montane Ultisol of Central Taiwan

蔣先覺(Hsien-Chueh Chiang) ； 陳尊賢(Zueng-Sang Chen) ； 許正一(Zeng-Yei Hseu)

《台灣林業科學》 12卷4期 (1997/12) Pp. 413-420

https://doi.org/10.7075/TJFS.199712.0413

摘要

透過偏光顯微鏡觀察土壤薄切片，可獲知許多土壤化育作用的證據，因此本研究選擇台灣中部一中海拔森林之極育土剖面，以微組構分析粘粒的移動及土壤中鐵瘤的微形態特徵。結果發現，強烈的粘粒洗入作用，使質地粘重的粘聚層土壤。在偏光顯微鏡下表現了明顯的條痕化雙折射組構，這些雙折射組構隨著鐵瘤的增加，而趨於圍繞在鐵瘤四周。粘粒髓質的走向，直接與水分的流動方向有關，而鐵在土壤中的分隔作用，除了受洗出、洗入作用及水分流動的影響，並形成鐵膜外，尚因氧化還原交替作用而明顯聚積在鐵瘤中。

關鍵字

薄切片 ； 微形態特徵 ； 鐵瘤 ； 粘聚層

並列摘要

Many evidences of genetic processes in soils could be found by viewing soil thin sections with polarized microscope. An Ultisol profile was collected from montane forest of central Taiwan to study their microfabrics associated with the movement of clay and the micromorphological characteristics of iron nodule. The observation of polarized microscopy, the thin sections of soil samples with fine texture in all argillic horizons indicate significantly striated b-fabrics attributed to strongly illuviation of clay. These b-fabrics tend to show grano-striations when iron nodule increased in the matrix. The orientation of clay plasma is directly related to water flow. Iron segregations in the soil pedon are not only influenced by eluviation, illuviation, and water flow to form ferrans, but also influenced by alternative oxidation and reduction cycles to form iron nodules.

並列關鍵字

thin section ； micromorphological characteristic ； iron nodule ； argillic horizon