西北和西南某废弃锑冶炼厂污染场地剖面土壤锑砷迁移性及其影响因素  

Soil antimony and arsenic migration characteristics and influencing factors in the contaminated site profiles of an abandoned antimony smelting plant in northwest and southwest

作　　者：黑儿平 何明江 喻华[1] 陈琨[1] 秦鱼生[1] 胡文 曾祥忠[1] 周子军 樊红柱[1] 上官宇先[1] 汪录英 HEI Erping;HE Mingjiang;YU Hua;CHEN Kun;QIN Yusheng;HU Wen;ZENG Xiangzhong;ZHOU Zijun;FAN Hongzhu;SHANGGUAN Yuxian;WANG Luying(Institute of Agricultural Resources and Environment,Sichuan Academy of Agricultural Sciences,Chengdu,610066,China;College of Agronomy,Sichuan Agricultural University,Chengdu,611130,China;Chengdu Jiaji Agricultural Technology Co.,Ltd.,Chengdu,610041,China)

机构地区：[1]四川省农业科学院农业资源与环境研究所,成都610066 [2]四川农业大学农学院,成都611130 [3]成都稼积农业技术有限公司,成都610041

出　　处：《环境化学》2025年第3期975-990,共16页Environmental Chemistry

基　　金：国家重点研发计划项目(2020YFC1807704,2020YFC1807703);四川省科技计划项目(2022YFN0066,2023YFS0483,2023YFS0485)资助.

摘　　要：针对矿业废弃地高背景值-历史矿业源相叠加区下土壤重金属污染问题,选取了西北地区甘肃西和和西南地区贵州晴隆两个地区的废弃锑冶炼厂旧址污染场地土壤作为对象,全面分析了土壤样品中镉(Cd)、铬(Cr)、镍(Ni)、铜(Cu)、汞(Hg)、铅(Pb)、砷(As)、锑(Sb)、氮(N)和磷(P)等元素含量,运用综合污染指数法、地累积指数法、潜在生态风险指数法以及风险评估编码法等多种方法进行了污染评估与生态风险评价.同时,初步探讨了元素总量,赋存形态以及土壤理化性质对Sb和As在土壤剖面中迁移行为的影响.结果表明,两个地区的废弃锑冶炼厂旧址污染场地表层(0—30 cm)土壤存在严重的重金属和养分污染风险.其中,Sb是最严重的污染物,其次是As、Cd、Hg、Pb、N和P,而Cr、Ni和Cu无污染风险.此外,随着土层深度的增加,Sb和As的总量逐渐减少.尤其在西南晴隆锑厂区,Sb含量下降更为显著.土壤中Sb和As的赋存化学形态方面存在明显差异,但它们主要以残留态形式存在(占65.0%—90.0%).土壤pH值、有机质含量和阳离子交换量是影响土壤中Sb和As迁移性的关键因素.当土壤呈碱性、有机质含量超过30 g·kg^(−1)以及阳离子交换量大于20 cmol·kg^(−1)时,Sb和As在不同土层中的积累达到最高水平.然而,这也会导致它们的生物有效性增加,提高迁移风险,尤其是在底层土壤中.建议在当前阶段可以考虑采用植物-稳定化技术联合修复治理这两个研究区:一方面通过投加吸附材料或生物碳基材料来促进土壤老化过程,从而加速Sb和As的不稳定形态向更稳定形态的转变;另一方面采取植被种植等修复方法来降低Sb和As的迁移性和生物有效性,并缓解营养污染风险.This study addresses the issue of heavy metal pollution in soil within the overlay area of high background values from mining waste land and historical mining sources.Soil samples were collected from an abandoned antimony smelting plant in Xihe,Gansu(northwest China),and Qinglong,Guizhou(southwest China).Comprehensive analyses were conducted on cadmium(Cd),chromium(Cr),nickel(Ni),copper(Cu),mercury(Hg),lead(Pb),arsenic(As),antimony(Sb),nitrogen(N),phosphorus(P),and other elements.Various assessment methods,including the comprehensive pollution index,geo-accumulation index,potential ecological risk index,and risk assessment coding,were employed to evaluate pollution and ecological risk.The study also explored the impact of total contents,chemical forms,and soil properties on the migration of Sb and As in the soil profiles.The findings indicated a significant risk of heavy metal and nutrient contamination in the surface soil(0–30 cm)of abandoned Sb smelting plant sites in both studied areas.Among these contaminants,the Sb emerged as the most serious pollutant,followed by As,Cd,Hg,Pb,N,and P.Conversely,Cr,Ni,and Cu posed no pollution risk.Furthermore,the total concentrations of Sb and As gradually decreased with increasing soil depth,with a more pronounced decrease observed in the Southwest Qinglong area.Distinct differences in geochemical fractionations of Sb and As were observed,and most of Sb and As existed in the form of residual fraction,accounting for 65.0%—90.0%of the total contents.Key factors influencing the mobility of Sb and As in the soil included soil pH,organic matter content,and cation exchange capacity.In alkaline soils,where the organic matter content exceeded 30 g·kg^(−1)and the cation exchange capacity surpassed 20 cmol·kg^(−1),the accumulation of Sb and As in different soil layers reached the highest levels.However,this circumstance also resulted in an elevated bioavailability of Sb and As,thereby increasing the risk of migration,particularly in subsoils.Notably,it is recommended to con

关 键 词：土壤 重金属 风险评估 迁移能力 

分 类 号：X-1[环境科学与工程] O6[理学—化学]