重庆市主要绿化植物对重金属的富集与净化研究

采集了重庆市主城区不同区域10种主要绿化植物、土壤和街道地表物(灰尘),分析了Hg,Cd,Cu,Pb,Zn在植物中的含量差异,分别计算了植物对土壤和灰尘重金属的富集系数以及植物对大气重金属的净化指数,同时进行了植物净化效果的聚类分析。结果表明,大渡口区域的重金属污染最严重,杜鹃对各重金属的富集能力较强。各植物对土壤和街道地表物(灰尘)重金属的富集系数无明显差异,但不同重金属之间则达到了极显著水平差异,Hg的富集系数最高。各植物对大气重金属的净化效果无明显差异,但不同重金属之间则达到了极显著水平差异,对Cu的净化效果最好。10种植物可划分为4种类型,即汞铜净化型、镉铅锌净化型、镉铜净化型和一般净化型。

ENRICHMENT OF HEAVY METALS BY SEVERAL VIRESCENCE PLANTS AND THEIR PURIFICATION OF THE ATMOSPHERE IN THE CENTRAL URBAN AREAS OF CHONGQING

Ten kinds of virescence plants accompanied by in situ soil and street-dust were sampled in different areas of the central urban zone of Chongqing,and Hg,Cd,Cu,Pb and Zn in the plants were determined.Based on these data,the concentration coefficients of plants to the heavy metals in soil and street-dust were calculated,and the purification indexes to heavy metals in the atmosphere were estimated.The results showed that Phododendron simsii Planch had a strong enrichment ability on heavy metals and Dadukou District suffered most severe pollution with heavy metals.No significant differences were noted between the plant species in their concentration index of heavy metals in soil and streetdust;however,significant differences existed among the heavy metals in their concentrations.The 10 plant species were classified into 4 categories,i.e.Hg-Cu purification type,Cd-Pb-Zn purification type,Cd-Hg purification type and common purification type.