Characteristics of spatial variability of plant diversity and soil nutrients in open-pit mining area

To study the effects of open-pit mining on natural plants and soil factors,We take the Inner Mongolia Nortel Shengli Mining Area as the study area.We us e field ecological survey methods to carried out plant community surveys on grassland at different distances around the mining area.and collectted soil samples around the mining area for laboratory analysis. The study results show that:①the natural flora of the grassland is dominated by Cleistogenes squarrosa,Carex duriuscula and Eragrostis minor,at a distance of 100 m away from the coal mine which is relatively disturbed by coal mines; the plant community at a distance of 400 m from the coal m ine is dominated by Stipa grandis,S. krylovii and Agropyron cristatum. Stipa grandis,Eragrostis minor and Cleistogenes squarrosa are mainly at a distance of 900 m;at a distance of 1 900 m from the coal mine, the vegetation community has stabillized with S. krylovi,Cleistogenes squarrosa and Stipa grandis.②Compared with the control area,the closer to the mining area,the plant diversity index decreased significantly,the community similarity decreased,and the soil water content,organic matter,nitrate n itrogen,and available phosphorus all decreased significantly.③The soil fertility far from the mining area is better than that near the mining area. Coal mining has an im pact on soil fertility within a certain range ,and the spatial heterogeneity of soil nutrients around the mining area changes to varying degrees .④Redundancy analysis sh ows that plant diversity index was positively correlated with soil water content,organic matter,nitrate nitrogen, available phosphorus and available potassium. The soil an d plants around the coal mining area are disturbed to a certain extent,and the soil nutrients are spatially heterogeneous. The succession of vegetation communities aro und the mining area has different needs for soil nutrients,and the changes of community species are obvious. Soil water content and organic matter account for a larger proportion of soil factors affecting plant community characteristics around the mining area. The grassland around the mining area is degraded to varying degrees. Under the premise of natural restoration, appropriate artificial interventions can be implemented to promote the restoration of grassland around the open-pit.