土壤氧化铁的形态在浙江红壤和黄壤分类中的意义

研究结果表明,红壤和黄壤之间铁矿物形态有明显的差异,黄壤的铁游离度、晶胶比以及赤铁矿系数均小于红壤;而铁活化度、络合态铁占游离态铁的百分比及氧化铁的水合系数都是黄壤高于红壤。黄壤以不含或仅含极少量的赤铁矿而区别于红壤。针铁矿普遍存在于所研究的各土壤中;部分土样还含少量纤铁矿。测定数据的统计分析表明,铁游离度、铁活化度以及赤铁矿系数等可以用来划分红壤、黄红壤和黄壤亚类。

Significance of Soil Iron Oxide Forms on Classification of Red Earth anh Yellow Earth in Zhejiang Province.

Research was conducted to explore the significance of iron oxides forms in soil classification, especially in the differentiation between the Red earth and Yellow earth. The results indicated that distinct difference existed between the forms of iron oxide mineral of the Red earth and those of the Yellow earth. The values of Fe ( d ) /Fe ( t ) , ( Fe ( d ) -Fe ( o ) ) /Fe ( o ) , and Hm%/ ( Hm% + Gt% ) , of the Yellow earth were lower than those of the Red earth, meanwhile, the values of Fe ( o )/Fe ( d ) , Fe(p)/Fe(d), and the hydration coefficient of Fe oxide of the Yellow earth were higher than those of the Red earth. The'corresponding values of the Yellow-Redfearth, a subgroup of Red earth, was just in the transitional range from the Red earth to the Yellow earth. The Yellow earth contained little or on hematite, which was distinctlly different from the Red earth that contained relatively abundant hematite. Goethite existed universally in soils studied contained lepidocrocite. It has been suggested tha some criteria might be feasiblly used to differentiate the Red earth from the Yellow earth by the values of Fe ( d )/Fe ( t ) , Fe ( o )/Fe ( d ) , Hm%/ ( Hm%+Gt% ) , etc. The ratio of hematite to the crystalline Fe oxides, expressed as Hm%/ ( Hm% +Gt% ) may perhaps be used to indicate the degree of laterization and to differentiate the Red earth from the Yellow earth.