低丘侵蚀红壤垦种熟化过程中土壤磁性特征演变规律

Soil Magnetic Characters of Hilly Eroded Red Soils After Cultivation

应用磁测方法并结合土壤理化指标 ,对相同母质发育但利用方式和熟化程度不同的浙西红壤磁性特征进行研究。结果表明 ,6种利用方式的红壤中 ,耕植年限长、熟化程度高的红壤由于土壤结构、p H值和有机质含量的改善 ,磁性特征有明显变化 ,磁性矿物由亚铁磁性矿物向不完整反铁磁性矿物方向发展 ,且超顺磁性矿物和单畴磁性矿物含量减少。此外 ,耕植年限相同的红壤磁性相近 ,裸地红壤的磁性低值反映了裸地表土强烈侵蚀状况。

Magnetic method associated with physical & chemical analysis were used to study magnetic characters in hilly red soils which have the same parent material but under different utilizations in western Zhejiang. The results showed that different utilizations have great effect on soil magnetism. Due to increasing soil water stable aggregates, soil pH and soil organic matter, some ferrimagnetic minerals transformed to imperfect anti ferromagnetic minerals, at the same time, the concentration of fine viscous minerals and single domain minerals were reduced, magnetic coefficients have been obviously changed. However, soil magnetism among soils which have same cultivated time was similar, low magnetism in bared soil indicated strong soil erosion.