广州市城市公园土壤重金属累积特征、形态分布及其生态风险  

Accumulation Characteristics,Geochemical Fractions Distribution and Ecological Risk of Heavy Metals in Soils of Urban Parks in Guangzhou,China

作　　者：谢邵文 郭晓淞 杨芬[5] 黄强[1] 陈曼佳 魏兴琥[1] 刘承帅 XIE Shaowen;GUO Xiaosong;YANG Fen;HUANG Qiang;CHEN Manjia;WEI Xinghu;LIU Chengshuai(School of Environmental and Chemical Engineering,Foshan University,Foshan 528000,P.R.China;Guangdong Laboratory for Lingnan Modern Agriculture,Guangzhou 510642,P.R.China;National-Regional Joint Engineering Research Center for Soil Pollution Control and Remediation in South China/Guangdong Key Laboratory of Integrated Agro-environmental Pollution Control and Management/Institute of Eco-environmental and Soil Sciences,Guangdong Academy of Sciences,Guangzhou 510650,P.R.China;State Key Laboratory of Environmental Geochemistry,Institute of Geochemistry,Chinese Academy of Sciences,Guiyang 550081,P.R.China;Key Laboratory of Land Surface Pattern and Simulation,Institute of Geographic Sciences and Natural Resources Research,Chinese Academy of Sciences,Beijing 100101,P.R.China)

机构地区：[1]佛山科学技术学院,广东佛山528000 [2]岭南现代农业科学与技术广东省实验室,广东广州510642 [3]广东省科学院生态环境与土壤研究所/华南土壤污染控制与修复国家地方联合工程研究中心/广东省农业环境综合治理重点实验室,广东广州510650 [4]中国科学院地球化学研究所/环境地球化学国家重点实验室,贵州贵阳550001 [5]中国科学院地理科学与资源研究所/陆地表层格局与模拟重点实验室,北京100101

出　　处：《生态环境学报》2022年第11期2206-2215,共10页Ecology and Environmental Sciences

基　　金：岭南现代农业科学与技术广东省实验室科研项目(NZ2021026);广东省科学院建设国内一流研究机构行动专项资金项目(2020GDASYL-20200301003;2020GDASYL-20200103083);国家重点研发计划项目(2020YFC1808500)。

摘　　要：城市公园土壤环境质量对城市绿色发展和居民健康均有重要影响。为了解广州市城市公园土壤中重金属含量、形态分布特征及其生态风险情况,以广州市核心城区典型城市公园表层土壤为对象,系统分析了土壤中Pb、Cd、Cr、Cu、Zn和Ni等6种重金属的含量;运用Tessier连续提取法分析重金属的可交换态(F1)、碳酸盐结合态(F2)、铁锰氧化态(F3)、有机态(F4)和残渣态(F5)等5种重金属形态的分布特征;同时运用次生相与原生相比值法(RSP)和风险评价编码法(RAC)对城市公园表层土壤重金属的生态风险进行了评估与讨论。结果表明,(1)广州市城市公园土壤中Pb、Cr、Cu、Zn、Ni和Cd的平均含量依次为64.71、58.55、37.59、131.04、23.16和0.54 mg·kg^(−1)。运用单因子指数法分析重金属累积特征发现,城市公园土壤中Pb、Cr、Cu、Zn和Ni为轻污染,仅部分区域为中污染,而Cd为重污染。(2)重金属形态分析表明不同重金属的形态分布特征存在较大的差异,Pb、Cr、Cu、Zn和Ni以残渣态和铁锰氧化态为主,而Cd以可交换态和铁锰氧化态为主。重金属形态分布的异质性也在一定程度上反映了重金属的迁移特性及其潜在环境风险的差异。(3)次生相与原生相比值法和风险指数编码法计算结果均表明广州市城市公园表层土壤中Cd的生态风险显著高于其他重金属,生态风险强弱顺序为Cd>Zn>Cu>Pb>Ni>Cr;空间分布上,核心城区中部(天河区、白云区和黄埔区)Cd的生态风险相对较高。综上所述,广州市核心城区城市公园表层土壤的主要重金属污染物为Cd,其生态风险远高于其他重金属,在今后粤港澳大湾区城市绿色发展及土壤环境风险管控中应当引起重视。Soil environmental quality of urban parks has an important impact on urban green development and residents'health.In order to understand the contents,geochemical fractions distribution characteristics and ecological risk of heavy metals in soils of urban parks in Guangzhou,the surface soils of typical urban parks in the core urban area of Guangzhou was taken as the object,and the contents of six heavy metals including Pb,Cd,Cr,Cu,Zn and Ni were systematically analyzed.The distribution characteristics of heavy metals in exchangeable fraction(F1),carbonate fraction(F2),Fe/Mn oxides fraction(F3),organic matter fraction(F4)and residual fraction(F5)were analyzed by Tessier’s extraction method.At the same time,the ecological risk of heavy metals in the soils of urban parks was assessed and discussed through the rations of secondary phase and primary phase(RSP)and risk assessment code(RAC)method.The results showed that(1)the average contents of Pb,Cr,Cu,Zn,Ni and Cd in urban park soils of Guangzhou were 64.71 mg·kg^(−1),58.55 mg·kg^(−1),37.59 mg·kg^(−1),131.04 mg·kg^(−1),23.16 mg·kg^(−1)and 0.54 mg·kg^(−1),respectively.The single factor index method was used to analyze the accumulation characteristics of heavy metals.It was found that Pb,Cr,Cu,Zn and Ni in urban park soils were light pollution,only some areas were moderately polluted,while Cd contamination was heavy.(2)The geochemical fractions analysis of heavy metals showed that there were great differences in the geochemical fractions distribution of different heavy metals.Specifically,Pb,Cr,Cu,Zn and Ni were mainly in the residual fraction and Fe/Mn oxides fraction,while Cd was mainly in the exchangeable fraction and Fe/Mn oxides fraction.The differences in the geochemical fractions distribution of heavy metals also reflected the differences in the migration characteristics and potential environmental risks of heavy metals.(3)The calculation results of RSP and RAC showed that the ecological risk of Cd in urban park soils in Guangzhou was signific

关 键 词：广州市 城市公园 土壤环境 重金属 形态分布 生态风险评价 

分 类 号：X53[环境科学与工程—环境工程] X820.4