合肥老城区土壤重金属分布格局及树木富集重金属潜力  

Distribution pattern of heavy metals in soil and the potential of heavy metal enrichment by trees in the old town of Hefei City

作　　者：张前进[1] 刘华[1] 陈永生[1] 王嘉楠[1] ZHANG Qian-jin;LIU Hua;CHEN Yong-sheng;WANG Jia-nan(School of Forestry and Landscape Architecture,Anhui Agricultural University,Hefei 230036,China)

机构地区：[1]安徽农业大学林学与园林学院,合肥230036

出　　处：《生态学杂志》2020年第12期4140-4147,共8页Chinese Journal of Ecology

基　　金：安徽省教育厅自然科学基金项目(KJ2019A0218);安徽乡村振兴战略研究中心2019年度重点课题“环巢湖地区乡村人居林景观风貌研究”资助。

摘　　要：为了解合肥老城区土壤重金属分布以及4种主要绿化树种广玉兰(Magnolia grandiflora)、桂花(Osmanthus fragrans)、香樟(Cinnamomum camphora)和悬铃木(Platanus acerifolia)重金属富集潜力,在城区不同绿地类型中共设36个取样点,分别收集土壤和树木二年生枝条样品,用电感耦合等离子体发射光谱法(ICP-AES)测定样品中Pb、Cd、Hg、Cr 4种重金属元素含量。结果表明:合肥老城区绿地土壤Cd、Pb、Hg 3种元素含量明显高于土壤背景值,分别是背景值的66.2倍、3.6倍和3.4倍,Cr含量稍低于背景值,说明老城区Cd污染最为严重;4种树木富集重金属的能力不同,Hg元素被植物富集的程度最高,其次是Pb和Cd,Cr被植物富集的程度最低;对Pb和Cd的富集能力大小顺序为桂花>广玉兰>香樟>悬铃木,对Hg的富集能力大小顺序为广玉兰>桂花>香樟>悬铃木,对Cr的富集能力大小顺序为香樟>悬铃木>桂花>广玉兰;研究的4种树木对重金属综合富集能力大小顺序为桂花>香樟>悬铃木>广玉兰;4种树木对Pb、Cd、Hg和Cr的富集量分别在4.0、0.2、0.45和0.6mg·kg^-1以下,4种树木对重金属富集储存均有很大的潜力。This study examined the distribution of heavy metals in soils of the old town of Hefei City and the enrichment potential of heavy metals by four main greening species including Magnolia grandiflora,Osmanthus fragrans,Cinnamomum camphora,and Platanus acerifolia.Soil and biennial branch samples were collected in 36 sites in different types of green space in the old town.The contents of Pb,Cd,Hg,and Cr in the samples were determined by inductively coupled plasma atomic emission spectrometry(ICP-AES).The results showed that soil Cd,Pb,and Hg contents in green space were 66.2,3.6,and 3.4 times higher than the background value in the soil of old town,respectively,whereas Cr content was slightly lower than the background value,indicating that Cd pollution was the most serious in the old town.In terms of the heavy metal enrichment potentials,Hg was the most enriched by trees,followed by Pb and Cd,and Cr was the least.The enrichment ability of trees for Pb and Cd followed the order of O.fragrans>M.grandiflora>C.camphora>P.acerifolia.For Hg enrichment,they followed M.grandiflora>O.fragrans>C.camphora>P.acerifolia.For Cr enrichment,they followed C.camphora>P.acerifolia>O.fragrans>O.fragrans>M.grandiflora.The order of comprehensive enrichment ability of the four tree species to heavy metals was O.fragrans>C.camphora>P.acerifolia>M.grandiflora.The concentrations of Pb,Cd,Hg and Cr in the four tree species were below 4.0,0.2,0.45 and 0.6 mg·kg^-1,respectively,indicating great potential for heavy metal accumulation and storage.

关 键 词：重金属污染 土壤 植物富集 分布格局 合肥 

分 类 号：X173[环境科学与工程—环境科学] X53