Abstract: Soil biological health assessment is an integral component of soil health evaluation, providing crucial insights into soil processes from a biological perspective. However, current soil health assessments primarily rely on soil physical and chemical indicators, lacking standardized methods and framework for incorporating soil biological indicators. We reviewed the development of soil health assessment and proposed a method, which incorporates the ‘dimension reduction’ of soil health index evaluation system using exploratory factor analysis and the ‘scoring’ based on cumulative normal distribution function into the soil biological health assessment. We further used this method to analyze soil biological health status of upland in black soil region at field and regional scales. The results showed that the use of exploratory factors could reflect soil biological health status in multiple dimensions, which was more conducive to formulating soil health conservation policies or measures according to local conditions. Our results highlighted the critical role of soil biota and their interaction networks in soil health assessment, which would provide necessary technical support for soil health assessment using soil biological indicators.

Key words: soil health, soil biological indicator, factor analysis, cumulative normal distribution function