摘要
采用ICP-OES测定北京市台基厂大街行道树国槐各器官中7种重金属(Cd、Cr、Ni、Cu、Mn、Pb、Zn)含量,比较不同径级国槐重金属富集效能。结果表明:国槐中重金属含量因胸径级、器官、元素种类不同而存在差异。各径级国槐重金属含量大小总体趋势为Zn>Mn>Cu>Pb>Cr>Ni>Cd,各器官中树皮和根对重金属的吸收能力最强,其次是叶和枝,树干对重金属的吸收能力最弱。不同径级国槐对重金属的富集能力存在差异,表现为小径级>中径级>大径级。国槐各器官中重金属积累量大小顺序为根>干>枝>叶,重金属积累量随着胸径级扩大和生物量的增加而增加。综合比较不同径级国槐重金属年均积累量、单位面积富集量和单位空间富集量,小径级(20≤DBH<30 cm)国槐富集效能最高。
The concentration of heavy metals （Cd, Cr, Cu, Mn, Ni, Pb, Zn） in roadside tree of Sophorajaponica L. and their organs along Taijichang Street was measured by using the Inductively Coupled Plasma Optical Emission Spectroscopy （ICP-OES） to compare the heavy metal enrichment capacity between different diameter classes. The results showed that the concentration of heavy metals in different diameter classes of Sophora japonica L., the concentration of the same element in different organs, and the concentration of different elements in the same organ were all different. In general, heavy metal concentration in Sophora japonica L. followed the order of Zn 〉 Mn 〉 Cu 〉 Pb 〉 Cr 〉 Ni 〉 Cd. The heavy metal absorption capacity in all organs followed the order of bark 〉 root 〉 leaf 〉 branch 〉 stem. Meanwhile, the study showed that the enrichment capacity of Sophora japonica L. in diameter at breast height （DBH） of small size was stronger than those of medium and large size. Heavy metal accumulation in different organs followed the order of root 〉 trunk 〉 branch 〉 leaf, which also increased in Sophora japonica L. with the increase of DBH and biomass. By comparing the accumulation per year, the bioenrichment unit area as well as the bioenrichment unit space of heavy metals with medium and large DBH, Sophora japonica L. of smaller DBH （ DBH less than 30 cm or more than 20 cm） had higher enrichment efficiency.
出处
《生态学报》
CAS
CSCD
北大核心
2015年第16期5353-5363,共11页
Acta Ecologica Sinica
基金
国家"十二五"(2011BAD38B03)科技支撑计划项目
关键词
径级
国槐
重金属
属行道树
富集效能
diameter class
Sophora japonica L.
heavy metal
roadside tree
enrichment efficiency
