摘要
探究贵州西部喀斯特地区森林土壤重金属的累积特征并对其污染程度进行评价,为该地区森林土壤健康状况及协调该地区经济发展与环境保护提供支持。以六枝花德河林场的亮叶桦林和青冈林土壤为研究对象,分析该区20个样地0~60 cm土层中As、Hg、Cu、Zn、Cd、Cr、Pb和Ni 8种重金属的含量并对其进行生态风险评价。结果表明,1)研究区亮叶桦林和青冈林土壤中Hg含量均较高,分别为0.2、0.17 mg·kg^(-1),严重超过贵州省背景值,其污染主要集中在土壤表层(0~10 cm土层)。而As含量仅在青冈林土壤中较高,为64.73 mg·kg^(-1),且As随土壤加深含量增加;此外,Cd、Cu、Hg和Ni含量变异程度大,受外源因子干扰强烈。2)森林土壤不同海拔的Hg含量均较高,在海拔1300 m达到超富集水平(EF=3.11);青冈林土壤中As含量在海拔1200 m达到超富集水平(EF=6.008),8种重金属含量与海拔分布无明显关系。3)经相关性分析和主成分分析后,Hg和As与其他6种重金属的相关性较低,说明Hg和As与其他6种重金属的来源不同,而Zn、Ni、Pb和Cu 4种重金属相关性较高,为同一来源。4)研究区亮叶桦林和青冈林的风险指数分别为99.46和107.63,均处于轻度生态风险,其中,Hg的潜在风险因子分别为72.76、62.03,均属中等生态风险,其余7种重金属为轻度生态风险,但仍有必要加强该区域重金属的监测工作。
The distribution characteristics of heavy metals in forest soils in the Karst area of western Guizhou was investigated and the pollution levels were evaluated to provide support for a comprehensive understanding of the health status of forest soils in the area to coordinate with local economic development and environmental protection.Taking the soils of Betula luminifera and Cyclobalanopsis glauca forests in the Liuzhihuade River Forest Farm as the research objects,the contents of 8 heavy metals,including As,Hg,Cu,Zn,Cd,Cr,Pb and Ni,in the 0-60 cm soil layer of 20 samples in the study area were analyzed,and the ecological risk assessments were carried out.The results showed that 1)the Hg contents in the soils of B.luminifera and C.glauca forests in the study area were higher,which were 0.2 mg·kg^(-1)and 0.17 mg·kg^(-1),respectively,seriously exceeding the background value in Guizhou Province.The pollution was mainly concentrated in the surface soil(0-10 cm soil layer).The content of As was 64.73 mg·kg^(-1)only in the soil of C.glauca forest,and As increased with soil depth.In addition,the contents of Cd,Cu,Hg and Ni varied greatly and were strongly disturbed by external factors.2)The Hg content was high at each altitude,reaching the super enrichment level(EF=3.11)at 1300 m above sea level.The content of As in the soil of C.glauca forest reached the super enrichment level(EF=6.008)at 1200 m above sea level,and the contents of 8 heavy metals had no significant relationship with the altitude distribution.3)Correlation and principal component analyses demonstrated that the correlation between Hg and As and other 6 heavy metals was low,indicating that Hg and As are different from the sources of other 6 heavy metals,while Zn,Ni,Pb and Cu and other 4 heavy metals had a high correlation and they are from the same source.4)The risk indices of B.luminifera forest and C.glauca forest in the study area were 99.46 and 107.63,respectively,which were in mild ecological risk,among which,the potential risk factors of Hg for two forests were 72.76 and 62.03 respectively,which were in medium ecological risks,and the remaining 7 heavy metals were in mild ecological risks.However,it is still necessary to strengthen the monitoring of heavy metals in this area.
作者
卢中科
曾钦朦
孙建昌
侯娜
LU Zhong-ke;ZENG Qin-meng;SUN Jian-chang;HOU Na(Guizhou Institute of Walnut,Guiyang 550005,Guizhou,China;Guizhou Academy of Forestry,Guiyang 550005,Guizhou,China)
出处
《西北林学院学报》
CSCD
北大核心
2023年第6期81-88,109,共9页
Journal of Northwest Forestry University
基金
贵州省科技厅重大专项(黔科合重大专项字[2019]3006)
贵州省科技厅重大专项(黔科合重大专项字【2019】3006-2)
贵州省科技厅优秀青年科技人才项目(黔科合平台人才[20195643])。
