Evaluation and Analysis of Soil Heavy Metal Characteristics in Typical Plateau Urban Green Spaces
LI Wei
XIE Pengcheng
DING Zhaowei
YANG Bo
ZHANG Na
XIONG Jian
LYU Xuebin
Abstract：The severe contamination of heavy metals in urban green areas has drawn considerable attention due to the sig-nificant threat to both the ecological environment and human health.In order to understand the soil environment in typical high-altitude cities,such as Lhasa,the distribution patterns and pollution status of eight heavy metals(Cu,Cr,Ni,Zn,Pb,Cd,As,and Hg)in the topsoil of 105 green areas was analyzed.The Absolute Principal Component Score-Multiple Linear Regres-sion(APCS-MLR)model was applied to reveal the sources of heavy metals.The results show that the contents of Cu,Cr,Ni,Zn,Pb,Cd,As,and Hg in the green areas of the study region were 31.00,43.00,18.00,70.00,33.70,0.15,18.00,and 0.079 mg/kg,respectively,which were 1.41,1.02,0.86,1.08,1.09,1.25,0.90,and 0.87 times of the urban background values,much lower than the limits specified in the Planting Soil Standards for Greening(CJ/T340-2016).Among the different types of green areas,Cu,Zn,Pb,and Cd had the highest concentrations in road-side green areas,while Cr,Ni,and As showed no sig-nificant variations among green area types.Hg had the highest content and a large coefficient of variation in park green areas.The comprehensive pollution index for the study area was 1.96,indicating a mild level of contamination.The mean values of the accumulation index for the eight heavy metals were all below 0,meaning no pollution.The integrated potential ecological risk index was 140.13,indicating a low ecological risk and good green area environmental quality.Traffic sources contributed to 36.78%,73.55%,82.24%,and 95.21%of Cu,Zn,Pb,and Cd,respectively.Natural sources contributed significantly to Cu,Cr,Ni,and As,with contributions of 59.64%,90.47%,97.00%,and 78.71%,respectively.Atmospheric deposition and mixed sources from agriculture and animal husbandry contributed the most to Hg,accounting for 74.24%.Herein,the primary risk fac-tors,Hg and Cd,in green areas should be paid more attention to prevent further accumulation in the soil.
Keywords：Lhasagreen spaceheavy metalsdistribution characteristicsabsolute principal component score-multiple lin-ear regression model
Publication Date：2023-12-28
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：11( 160-170 )