In order to provide a guide for plant selection of ecological restoration at antimony (Sb) mining ecological damaged sites, species composition, importance value, niche, and interspecific associations of tree, shrub, and herb layers were examined at Sb mining site in Nandan City, Guangxi, China. The results showed that 23 vascular plant species were recorded at the Sb mining ecological damaged site, belonging to 22 genera and 13 families, primarily Gramineae, Cyperaceae, Fabaceae, and Asteraceae. The highest importance values for trees, shrubs, and herbs were observed in Rhus chinensis (56.7%), Coriaria nepalensis (56.3%), and Eremochloa ciliaris (44.0%), which were characterized by fairly large niche widths of 1.58, 1.32 and 1.57, respectively. The highest niche overlap values were found between R. chinensis and Triadica sebifera in the tree layer, and between Thysanolaena latifolia and Bidens pilosa in the herb layer, with the value of 0.68 and 0.99, respectively. Shrub layer exhibited a lower range of niche overlap (0.30-0.42), suggesting significant niche differentiation among different species. In the tree and shrub layers, most species showed insignificantly negative associations, the proportion was 83.3% and 66.7%, respectively, indicating that the plant community was not stable. Herb layer generally exhibited significantly positive correlations, with 52.4% of species pairs showing positive correlation, indicating weak resource competition among species. Overall, plant community at Sb mining ecological damaged site was unstable. In the process of ecological restoration, trees and shrubs that can adapt to the conditions and have positive associations should be prioritized in species selection, such as R. chinensis, C. lanceolata, C. nepalensis, and B. nivea. This will promote vegetation positive succession, rehabilitate the ecosystem and ensure sustainable development at Sb mining ecological damaged sites.
本文研究了广西南丹锑矿生态破坏区植物群落乔木层、灌木层和草本层物种组成、重要值、生态位和种间联结特征,以期为锑矿生态破坏区的生态恢复提供植物选择依据。结果表明: 锑矿生态破坏区有维管植物共23种,隶属13科22属,多为禾本科、莎草科、豆科和菊科。乔木层、灌木层和草本层重要值最大的植物分别是盐麸木(56.7%)、马桑(56.3%)和蜈蚣草(44.0%),而且具有较大的生态位宽度,分别为1.58、1.32和1.57。乔木层盐麸木与乌桕(0.68)、草本层粽叶芦与鬼针草(0.99)生态位重叠值最大,而灌木层物种生态位重叠值较低(0.30～0.42),表明灌木层物种生态位分化程度较大。乔木层和灌木层物种总体呈不显著负联结,主要物种间多数呈负相关(占比分别为83.3%和66.7%),植物群落不稳定;草本层物种总体呈显著正联结,种对间正相关物种对数占比为52.4%,物种竞争较弱。总体而言,锑矿生态破坏区植物群落不稳定,在生态恢复过程中,可以选择补充适宜该区生长且具有正联结的灌木和乔木,如马桑和苎麻、盐麸木和杉木等,促进植物群落正向演替,推动锑矿生态破坏区生态系统重建和可持续发展。.
Keywords: antimony (Sb) mining ecological damaged site; importance value; interspecific association; niche; plant species.