Spatial variability of soil magnetic susceptibility under different scales: a case study of Xiangtan

The characteristics of soil magnetic parameters can reflect the natural environment evolution and the human activities influence. By systematically sampling and measuring the sediments and onshore soils in representative water of Xiangtan City, spatial estimation was carried out by Kriging Spatial Interpolation with the help of SPSS, ArcGIS, Surfer, and other statistical and spatial analysis software. The results showed that: (1) Under the city scale, the spatial variation of soil magnetic susceptibility was large and ranged from 1.167×10⁻⁸ m³ kg⁻¹ to 165.93×10⁻⁸ m³ kg⁻¹; (2) the soil magnetic susceptibility varies greatly under different land-use patterns, which may be related to the accumulation and absorption of magnetic substances in the soil environments. On the functional area scale, human activities on soil magnetic susceptibility were relatively large, which might be closely related to agricultural activities and domestic waste discharge; (3) the distribution of soil magnetic susceptibility was mainly affected by various factors; (4) the spatial autocorrelation distance decreased from the city scale to the functional area scale. Structural elements, such as sedimentation, topographic gradient, animals and plants, have a more significant influence on the spatial distribution of soil magnetic susceptibility. (paper)