Comment on Determine Methods for the Soil Elements Background

Four commonly used methods to determine background concentrations of soil elements are compared and analyzed. The methods cover Iterative 2-σ technique, Accumulative Frequency method, Standardized method and Deep Layer Soil Element method. Iterative 2-σ technique is applicable to assess the background concentrations of soil elements in regions with homogeneous parent materials. Accumulative Frequency method can determine the background concentrations precisely in regions with non-homogeneous parent materials. For the regions where human behaviors are active, Standardized method and Deep Layer Soil Element method are applicable.