金华城区表层土壤剖面磁化率变化规律

Research for Variation Rule of Magnetic Susceptibility of Surface Soil in Jinhua City

以金华城区表层土壤剖面为研究对象,分析土壤剖面磁化率的分布特点。结果表明：19个土壤剖面的磁化率分布在11.22×10-8~94.29×10-8 m3/kg之间;19个剖面土壤磁化率在0—10cm的垂向剖面上的变化有三种不同形式：一是先增大后减小且在3cm左右出现极值,二是单调变化,又可细分为单增和单减,三是波动变化,也可细分为波动增加和波动减小;通过对比不同采样间隔下磁化率的变化情况,结合土壤磁化率垂向分布特征和统计结果,建议以1—3cm作为采样深度可以更好地揭示人类活动对土壤磁化率的影响。

Urban surface soils in Jinhua were seleced as the research examples. The distribution characteristics of surface soil magnetic susceptibility were analyzed to explore the optimization problem of sampling way. Magnetic susceptibility of selected 19 soil samples ranged from 11.22 × 10-8 to 94.29 × 10-8 m3/kg in urban area. Sampling interval is set to 1 cm, statistics showed that each depth level of 19 susceptibility profiles has different valuea. Soil magnetic susceptibility in the depth of 0 to 10 cm changes in three different forms, the first presents the first increase and then decreases, the peak occurs in the depth of about 3 cm, the second is monotonous, and can be subdivided into single increase and decrease, the third demonstrates the fluctuation change, can also be subdivided into fluctuation increase and decrease. Considering the profile magnetic sus- ceptibility variation and studing the magnetic susceptibility of soil profile, we had better to select the investi- gated soils in the typical research areas, analyze the change character of magnetic susceptibility in the profile, and then determine the optimal sampling thickness or layer. It can be better reflect profile susceptibility peak