青海湖北部高寒草地土壤粒度与磁化率关系探讨

文章以青海湖北部刚察县高寒草地为研究对象,分析测试土壤样品的各粒级组分进而计算出各粒度参数值,尝试探索土壤层剖面的土壤粒度与土壤磁化率的变化特征及其相关性。结果表明:该高寒草地土壤剖面粒度组成以粉砂为主,黏粒次之,再次是砂粒,土壤属性属于粉砂壤土—粉砂土;土壤质量磁化率总体较低,土壤物源既有基岩风化而成,又有远程物质的搬运沉积;土壤剖面上表现出两个较为明显的质量磁化率由高到低的周期演化,说明成土成壤过程经历了两个时期。土层在30 cm以上,质量磁化率与频率磁化率呈现出相反的变化趋势;30 cm以下随着越接近母岩方向,质量磁化率值呈现减小的态势。且在剖面上表现出两个较为明显的以高质量磁化率值开始、低质量磁化率结束为特征的周期演化。

Discussion on the relationship between soil particle size and magnetic susceptibility of alpine grassland in northern Qinghai Lake area

This paper deals with alpine grassland in the north Qinghai Lake area trying to find out relationship between soil particle size and magnetic susceptibilityby means of meassuring each soil particle size groups and calculating the particle size parameter. The results show that the the alpine grassland section was dominated by silt, then clay, sand. The soil belongs to silt loam-silt soil including the weathered materials of bed rock and the deposited long-distance-transported materials. The mass magnetic susceptibility is generally low. The soil section includes two distinct evelution cycles of mass magnetic susceptibility from high to low indicating that the soil is formed in two periods. Above 30cm of the soil layer the mass magnetic susceptibility and the frequency susceptibility change in opposite tendency; below 30cm, close to the bedrock, the mass susceptibility decrease.