中条山铜尾矿坝自然定居草本植物群落特征

Characteristics of naturally colonized herbaceous plant communities in the tailings dam of the Zhongtiaoshan copper mining area

为筛选适合铜尾矿生态修复的植物种类,采用TWINSPAN等级分类、DCA排序、M. Godron稳定性、物种多样性指数等方法,对山西中条山铜矿区十八河尾矿坝自然定居草本植物群落特征进行研究。结果显示:1)研究区自然定居草本植物群落中54个样方共记录43种,隶属15科37属;2)TWINSPAN等级分类将研究区自然定居草本植物群落54个样方划分为10个群丛,用Ⅰ~Ⅹ表示。位于尾矿坝最高处的群丛Ⅹ恢复年限最短,位于尾矿坝底部的群丛Ⅰ、Ⅱ恢复年限最长;3)10个群丛群落稳定性排序为:Ⅳ>Ⅷ>Ⅶ>Ⅴ>Ⅰ>Ⅲ>Ⅵ>Ⅹ>Ⅸ>Ⅱ,均处于较不稳定状态;4)DCA排序第1轴反映恢复年限和尾矿坝海拔的变化,DCA第2轴反映植物生态类型的变化;5)恢复年限是影响中条山铜矿区尾矿坝自然定居草本植物群落组成的主要限制因子;6)单因素方差分析显示,10个群丛的物种丰富度指数、Shannon-Wiener多样性指数有显著差异(P<0.05)。优势种狼尾草和白羊草可用于未来该尾矿坝生态修复中。

[Background]Mine tailings are one of the most serious and longest lasting products of environmental damage generated by mining activities.As an extremely degraded habitat,the tailings dam in the Zhongtiaoshan copper mine area is extremely difficult to restore the vegetation,and ecological restoration is urgently needed.The characteristics of naturally colonized herbaceous plant communities in the Shibahe tailings dam of the Zhongtiaoshan copper mining area were studied to reveal the relationship between herbaceous community diversity and environmental factors,and to screen out the dominant herbaceous species suitable for ecological restoration of tailing dam in copper mine area,so as to provide scientific basis for ecological restoration of tailing dams in copper mine area.[Methods]In September 2020,a total of 54 sampling plots were surveyed in 1 m×1 m samples of the naturally colonized herbaceous plant community at the tailings dam in the Zhongtiaoshan copper mining area according to the gradient change in elevation.The characteristics of naturally colonized herbaceous plant community in the tailings dam of Zhongjianshan copper mine area,was studied by using the methods of TWINSPAN classification,DCA ordination,M.Godron stability,and species diversity index.SPSS 20.0,Excel 2010 and Origin 2021 software were used for data analysis.[Results]1)A total of 43 species belonging to 16 families and 38 genera were recorded in 54 sampling plots in the naturally colonized herbaceous plant community of the study area.2)54 sampling plots of naturally colonized herbaceous plant communities in study area were divided into ten associations(Ⅰ-Ⅻ)by TWINSPAN classification.AssociationⅩlocated at the top of tailings dam had the shortest revegetation period,while Associations I and II located at the bottom of tailings dam had the longest revegetation period.3)The community stabilities of the ten Associations were ranked as follows:Ⅳ>Ⅷ>Ⅶ>Ⅴ>Ⅰ>Ⅲ>Ⅵ>X>IX>Ⅱ,which indicated that all the ten Associations were in a relatively unstable state.4)The first DCA axis of 54 quadrats represented the changes of the revegetation period and the altitude of the tailings dam,and the second DCA axis represented the change of plant ecotypes.5)The revegetation period were the major limiting factors affecting the composition of the naturally colonized herbaceous plant communities in the tailings dam of the Zhongtiaoshan copper mining area.6)One-way ANOVA showed that the Patrick richness index and Shannon-Wiener heterogeneity index of ten Associations were significantly different(P<0.05).[Conclusions]The dominanrt plant species of Pennisetum alopecuroides and Bothriochloa ischaemum could be used in the ecological restoration of the tailings dams of Zhongjianshan copper mine area in the future.