云南兰坪铅锌矿区优势植物重金属富集特性及应用潜力

为筛选适合云南高原地区重金属污染土壤修复治理以及矿区生态复垦的植物材料,通过实地野外调查,采集云南兰坪铅锌矿区18种优势植物样品及相应根系土壤,测定其Cd、 Cr、 Cu、 Ni、 Pb和Zn含量,计算植物对重金属的富集和转运系数,通过聚类分析方法,综合评估植物的应用潜力.结果表明, 18种优势植物分属18属13科,均为草本植物.植物体内多种重金属含量均高于植物正常含量,其中,延胡索(Corydalis yanhusuo)、旱芹菜(Carum bretschneideri)和毛连菜(Picris hieracioides)地上部Cd含量分别达到62.29、 76.49和85.09 mg·kg~(-1),Cd富集系数分别为0.57、 0.58和0.66,转运系数分别为0.89、 0.45和1.48,有着较强的吸收和转移土壤重金属Cd能力,具有修复Cd污染土壤潜力.狼毒(Euphorbia fischeriana)和倒提壶(Cynoglossum amabile)地上部Cd含量分别为0.46 mg·kg~(-1)和0.23 mg·kg~(-1),富集系数均小于0.01,属于重金属低积累植物,适合在中国西南高海拔地区生长,两种植物可以考虑作为Cd污染农田安全利用经济植物.其余13种植物对矿区重金属污染有着较好的耐性,可以用作矿区植被修复.

Potential of Accumulation and Application of Dominant Plants in Lanping Lead-zinc Mine, Yunnan Province

A field investigation in the abandoned lead-zinc mines in Yunan Province was conducted to assess the accumulation potential of dominant plant species and six heavy metals in mine soils. Eighteen types of plants were selected for the analysis. Local plants and soil were sampled and analyzed for cadmium (Cd), chromium (Cr), copper (Cu), nickel (Ni), lead (Pb), and Zn (zinc) concentrations. Bioconcentration and translocation factors were calculated. Cluster analysis was performed to calculate the accumulation potential. The results showed that all dominant plants (18 species and 13 families) were herbaceous plants. The content of heavy metals in these plants was higher than their normal content in plants. The above-ground Cd content of Corydalis yanhusuo, Carum bretschneideri, and Picris hieracioides reached 62.29, 76.49, and 85.09 mg ·kg^-1. The bioconcentration factors of Cd in these three plants were 0.57, 0.58, and 0.66, and the translocation factors were 0.89, 0.45, and 1.48, respectively. These plants have a strong ability to absorb and transfer Cd in soil; hence, they have the potential to remediate the Cd-contaminated soil. The above-ground Cd content of Euphorbia fischeriana and Cynoglossum amabile were 0.46 mg ·kg^-1and 0.23 mg ·kg^-1, respectively, and the bioconcentration factors were less than 0.01. These two plants accumulate low levels of heavy metals and thus, are suitable for growth in high altitude areas of Southwest China. They are considered economic plants for safe use in Cd-contaminated farmlands and have high application value. To protect the ecological environment of the mining areas, the other 13 plants having good tolerance to heavy metal pollution can be used as vegetation restoration plants in mining areas.