不同恢复年限矿山排土场植物群落特征

Vegetation community characteristics of mine dumps under different recovery years

为研发适宜于干热河谷矿山排土场的生态恢复技术,采用数量生态学样方调查的方法对攀枝花地区钒钛磁铁矿区5 个不同恢复年限的排土场进行植被群落特征调查,记录植物物种,计算物种重要值、群落多样性、均匀度和相似性等指标。结果表明,矿山排土场植被种类较为稀少,共36 种。其中,禾本科种类最多,其次为菊科和豆科植被;扭黄茅(Heteropogon contortus)、芦苇(Phragmites australis)和碱蓬(Suaeda glauca)等草本植被在排土场优势程最大,是金属矿山排土场的耐性物种;以草本为主的灌草丛是矿山排土场植被恢复前期的优势群落类型;恢复演替过程中,物种数量和多样性均呈现先增加后减少的趋势,各物种间存在竞争淘汰关系;10 年内不同恢复年限的矿山排土场植被群落间的差异性较大。

To explore an appropriate ecological recovery technology for mine dumps,a quantitative ecological sampling survey method was used to conduct a field survey of the vegetation community in five dumps in different recovery years in Panzhihua V-Ti-Magnetite zone.The vegetation species of each mine dump was recorded,and then importance value, community diversity,evenness,and community similarity were measured.Thirty-six types of plant species were identified in the mine dumps.Among the plant species,Gramineae was the largest group,followed by Compositae and Leguminosae. Herbaceous such as Heteropogon contortus,Phragmites australis,and Suaeda glauca showed the greatest superiority degrees and were tolerant to metal mine dumps.Herb-based shrubs were the dominant community type in the early stage of vegetation restoration in the mine dumps.During recovery and succession,the number and diversity of species showed an increasing trend during the initial stage,and then a decrease over time.Additionally,an interspecific competition relationship was discovered among different species.Significant differences were found among the vegetation communities of mine dumps in different recovery years.