辽宁朝阳第四纪古红土的矿质元素与氧化铁特性研究

Study of the Mineral Elements and Iron Oxide of Quaternary Red Palaeosols in Chaoyang Area Liaoning Province

以辽宁省朝阳地区5个具有代表性的第四纪古红土剖面为研究对象,经大量室内分析,研究其土壤中矿质元素的剖面分布状况及其氧化铁的分布特征。结果表明:供试土壤土体中矿质元素的含量顺序依次为SiO2>Al2O3>Fe2O3>K2O>MgO≈CaO>TiO2>Na2O>MnO>P2O5。SiO2、Al2O3和Fe2O3在同一剖面土层间相差不大,土壤的化学风化程度较弱。氧化铁全量含量变化不大,剖面B层游离氧化铁含量较高,土壤具有铁质特性,但是游离度不高,土壤富铁铝化程度较低。供试土壤活性氧化铁含量不高,活化度也很低,土壤氧化铁多处于结晶状态,老化程度高。

The distribution of mineral elements in soil profiles and iron oxide were analyzed based on five representative samples of the Quaternary Red Falaeosols in Chaoyang area Liaoning Province .The results showed that： the contents of mineral elements of the tested soil was： SiO2〉Al2O3〉Fe2O3〉K2O〉MgO CaO〉TiO2〉Na2O〉MnO〉P2O5. Al2O3 and Fe2O3 are evenly distributed in soil profile with weak weathering degree. The content of iron oxide changed a little, the free iron oxide in profile B was much higher; the soil has iron character with low freeness. The content of tested activated ferric oxide as well its activation grade was lower, while the soil iron oxide was in crystallized state with higher aging degree.