湿地池杉不同营养器官富集重金属特征  

Enrichment characteristics of heavy metals in different vegetative organs of Taxodium ascendens wetland forests

作　　者：骆子璇 胡海波[1] 贾西川 陈建宇 LUO Zixuan;HU Haibo;JIA Xichuan;CHEN Jianyu(Co-Innovation Center for Sustainable Forestry in Southern China/Key Laboratory of Soil and Water Conservation and Ecological Restoration,Nanjing Forestry University,Nanjing,Jiangsu 210037,China)

机构地区：[1]南京林业大学南方现代林业协同创新中心/江苏省水土保持与生态修复重点实验室,江苏南京210037

出　　处：《福建农林大学学报（自然科学版）》2022年第6期767-773,共7页Journal of Fujian Agriculture and Forestry University:Natural Science Edition

基　　金：国家林业和草原局长江三角洲森林生态系统定位研究项目(2020132077);江苏省林业科技创新与推广项目(LYKJ[2020]扬州仪征01);江苏省高等学校林学优势学科建设项目(164010641)。

摘　　要：以南京江北地区5片典型湿地池杉林为研究对象,测定底泥及池杉不同营养器官中重金属铜(Cu)、锌(Zn)、铬(Cr)、铅(Pb)的含量,利用富集系数和转移系数对池杉不同营养器官吸收重金属的能力进行评价.结果表明:(1)5片湿地池杉林底泥和各营养器官中重金属元素含量大体表现为Zn>Cr>Cu>Pb,且4种重金属元素的潜在生态风险指数均未超过40,属于轻微生态危害;(2)池杉不同营养器官中重金属含量具有一定差异,树皮、树枝和树根重金属含量较高,树叶则普遍较低;(3)池杉各营养器官对4种重金属元素的富集系数为0.07~1.76,总的富集能力表现为树枝>树根>树皮>树叶,池杉对各重金属元素的综合富集能力排序为Zn>Pb>Cu>Cr,其中,树枝对Zn的富集能力最强,平均富集系数为0.99,树根对Cu的富集能力最强,平均富集系数为0.63,树皮对Pb的富集能力最强,平均富集系数为0.62,而池杉树根、树皮、树枝对Cr的富集系数无显著差异;(4)池杉各营养器官对4种重金属元素的生物转移系数为0.27~2.48,转移能力排序为树皮>树枝>树叶.因此,池杉对底泥重金属污染具有一定的修复作用.To investigate the heavy metal adsorption ability of Taxodium ascendens,the enrichment ability and transfer coefficient of T.ascendens were assessed based on the contents of copper(Cu),zinc(Zn),chromium(Cr)and lead(Pb)in the sediments and different vegetative organs of 5 T.ascendens forests,which were typical wetland forests located in Jiangbei area of Nanjing Province.The results showed that:(1)The contents of heavy metal elements in the sediments and vegetative organs followed the order of Zn>Cr>Cu>Pb;with overall potential ecological hazard coefficients below 40,the 4 heavy metal elements were considered minor ecological hazard in the study area.(2)The contents of heavy metals varied among different vegetative organs,which were highly accumulated in the bark,branch and root while were less accumulated in the leaves.(3)The enrichment coefficients of the 4 elements varied from 0.07 to 1.76 among the organs,the total accumulative ability of all heavy metals followed the order of branch>root>bark>leaf and the comprehensive enrichment capacities followed the sequence of Zn>Pb>Cu>Cr.Branch demonstrated the greatest Zn-enrichment ability with an average enrichment coefficient of 0.99,and root and bark showed the highest enrichment ability towards Cu and Pb,respectively,reaching a similar average enrichment coefficient of 0.63 and 0.62,respectively.However,the enrichment coefficient of Cr did not vary significantly among all the vegetative organs.(4)The overall biological transfer coefficient of T.ascendens to the 4 heavy metal elements reached 0.27-2.48.And the bark of T.ascendens was the organ with the greatest transfer capacity,which was followed by branch and leaf in a descending order.To a certain extent,T.ascendens is capable of purifying heavy metals from polluted sediments.

关 键 词：池杉 底泥 重金属 富集特征 

分 类 号：S791.34[农业科学—林木遗传育种]