Objective In response to the decline of soil fertility and deterioration of the ecological environment in Xing’an League, multiple soil samples and indicators were selected to conduct a health assessment of the soils, which aimed to clarify the level of soil health in different areas and identify the obstacles to soil quality improvement, so as to provide theoretical support for the conservation and improvement of the soil health.

Method A total of 300 soil samples were collected, 13 soil physical, chemical and biological indices were determined. The minimum data set of soil health evaluation was screened by cluster analysis, and the health evaluation of Xing’an League black soil was carried out by fuzzy mathematical synthesis, common factor variance method and comprehensive index method.

Result The contents of soil organic matter of the black soils in Xing’an League was quite stable with little spatial variability. The spatial variations of soil pH, bulk density, total nitrogen, available potassium, Olsen-P, ammonium nitrogen, urease and sucrase liveness were at low level. The spatial variabilities of soil water content, cation exchange capacity and nitrate nitrogen was larger, and the spatial variability of soil electric conductivity was the greatest. The minimum data set for soil health assessment of Xing’an League black soils was composed by soil organic matter, Olsen-P, total nitrogen, available potassium, cation exchange capacity, pH, bulk density, soil urease and soil sucrase. The weight of the evaluation indicators of the minimum data set were obtained by the common factor variance method, and their contribution rates to soil health were as follows: soil organic matter 12.73%, olsen-P 9.14%, total nitrogen 12.99%, available potassium 9.75%, cation exchange capacity 9.53%, pH 11.56%, bulk density 11.43%, soil urease 9.36% and soil sucrose 13.5%. The soil comprehensive index of Xing’an League black soil ranged from 0.40 － 0.75, with an average of 0.57, which indicated that soil health was at a medium level. Horqin Youqi had the highest level of soil health.

Conclusion The soil physical and chemical properties of the black soil area in Xing’an League exhibit variability, which can be assessed for soil health in different regions by selecting sensitive indicators, establishing the minimum data set and calculating comprehensive soil index. The research results can provide scientific basis for the conservation of black soil in Xing’an League and promote the sustainable use of black soil.