Background Ecological restoration in mining areas is essential for achieving sustainable development. This study focuses on the coal mining sites in Jungar Banner, Inner Mongolia, a typical region suffering from vegetation degradation and soil damage due to mining activities and is now undergoing ecological restoration. The aim is to evaluate the effectiveness of ongoing restoration efforts by comparing plant community structure and soil properties between restored and undisturbed areas.
Methods The study was conducted in three coal mines—Huafu, Mengxiang, and Tingziyan. Plant community surveys and soil sampling were carried out on both artificially restored slopes and adjacent undisturbed vegetation areas. Species composition, diversity indices, soil properties, and heavy metal content were measured and statistically analyzed.
Results 1) A total of 71 plant species belonging to 53 genera and 21 families were recorded across the studied sites. The dominant families were Poaceae, Fabaceae, and Asteraceae. Distinct differences in dominant species composition were observed between undisturbed and restored areas. Undisturbed vegetation areas were primarily dominated by Armeniaca sibirica, Caragana korshinskii, and Artemisia capillaris, whereas artificially restored slopes exhibited dominance by artificially cultivated species such as Picea asperata, Artemisia ordosica, and Medicago sativa. 2) Species diversity indices revealed significant disparities between restored and undisturbed areas.The Shannon-Wiener diversity index decreased by 35.7%−69.3%, and the Margalef richness index declined by 12.0%−44.8%. The Simpson index in Huafu restored slope dropped by 57.4 % (P < 0.05). However, no significant difference was found in the Pielou evenness index, suggesting that species distribution uniformity remained relatively stable despite reduced overall diversity. 3) Soil properties improved notably after restoration. The soil pH value of the restored slope decreased by 3.3%−6.8% compared to the undisturbed vegetation area, while organic matter, total nitrogen, and available phosphorus increased by 124.4%−479.8%, 54.6%, and 93.0%−98.5%, respectively (P < 0.05). Heavy metals remained within safe limits, with arsenic (As) and lead (Pb) concentrations in restored slopes increasing by 96.1%−464.1% and 130.7%, and mercury (Hg) and nickel (Ni) levels decreasing significantly by 95.2%−96.3% and 32.9%−62.1% (P < 0.05) 4) Correlation analyses highlighted strong interactions between species diversity and soil factors. Species diversity indices correlated positively with pH, organic matter content, lead (Pb) and mercury (Hg) content, but negatively with total nitrogen. These relationships underscore the importance of integrating soil quality management with vegetation community design in restoration practices.
Conclusions Ecological restoration in Zhungeer Banner has preliminarily improved soil quality and established pioneer plant communities. However, the lower species diversity on restored slopes indicates the need for better species selection and ecological management. Future efforts should emphasize the integration of soil and vegetation restoration to enhance ecosystem sustainability.
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