湖南某锡矿区土壤稀土空间分布与生态风险评价  

Spatial Distribution and Ecological Risk Assessment of Soil Rare Earth in a Tin Ore Area of Hunan Province

作　　者：李剑锋 柴启森 王岚[3] LI Jian-Feng;CHAI Qi-Sen;WANG Lan(Wuhan Center,China Geological Survey(Geosciences Innovation Center of Central South China),Wuhan 430205,Hubei,China;Research Center for Petrogenesis and Mineralization of Granitoid Rocks,China Geological Survey,Wuhan 430205,Hubei,China;College of Geographic Science,Liaoning Normal University,Dalian 116029,Liaoning,China)

机构地区：[1]中国地质调查局武汉地质调查中心(中南地质科技创新中心),湖北武汉430205 [2]中国地质调查局花岗岩成岩成矿地质研究中心,湖北武汉430205 [3]辽宁师范大学地理科学学院,辽宁大连116029

出　　处：《华南地质》2025年第1期148-157,共10页South China Geology

基　　金：中国地质调查局花岗岩成岩成矿地质研究中心开放基金课题(PMGR202009、PMGR202108,PMGR202115);中国地质调查局项目(DD20190154、DD20221689、DD20243431)。

摘　　要：为科学评价矿区土壤稀土空间分布与风险,本文采集某锡矿区表层土壤样品141件、柱状土壤样品3组30件,分析测定14种稀土元素含量;采用单项污染指数、地累积指数、内梅罗综合污染指数、潜在生态风险指数等方法对其进行系统研究。结果表明:(1)全部样品14种稀土元素均值全部超出湖南省土壤背景值;其地累积指数(I_(geo))从大到小依次为:Tm(0.468)>Pr(0.420)>Tb(0.403)>Nd(0.377)>Dy(0.320)>Sm(0.317)>Ho(0.267)>Yb(0.157)>Er(0.150)>Eu(0.117)>Lu(0.112)>Gd(0.051)>La(0.021)>Ce(-0.159),均属无污染范畴;内梅罗综合污染指数(P_(N))显示全部样品综合污染指数集中于0.29~8.96,平均2.48,以轻度污染为主;(2)潜在生态风险因子(E_(r)^(i))占比表明,La、Ce、Yb,Pr、Nd、Sm、Eu、Gd、Dy、Er,Tb、Ho、Tm样本轻微生态风险占比分别为100%、>90%和>84.8%;潜在生态风险指数(RI)为25.43~1904,平均199.44;处于中度生态风险水平;(3)ΣREE、L_(REE)、P_(N)及RI的空间变化规律一致,证实区内表层土壤稀土富集主要受花岗岩风化作用和水文条件控制,而矿业开发对其影响有限。总之,区内土壤稀土污染和生态风险均很低,处于安全可控状态。To evaluate the spatial distribution and risk of rare earth in mining soil,in this paper,141 pieces of surface soil and three sets of 30 pieces of columnar soil were collected from a tin mining area,and then 14 kinds of rare earth elements content of these samples were analyzed and determined.It was systematically studied by single pollution index,the geo-accumulation index,Nemerow comprehensive pollution index and potential ecological risk index.The results showed that:(1)the average values of 14 rare earth elements in all the samples exceeded the soil background values in Hunan Province;The geo-accumulation index(I_(geo))in descending order is:Tm(0.468)>Pr(0.420)>Tb(0.403)>Nd(0.377)>Dy(0.320)>Sm(0.317)>Ho(0.267)>Yb(0.157)>Er(0.150)>Eu(0.117)>Lu(0.112)>the Gd(0.051)>La(0.02)>Ce(−0.159),indicating they are pollution-free;The Nemerow comprehensive pollution index(P_(N))showed that the comprehensive pollution index of all samples was concentrated in 0.29~8.96, with an average of 2.48, suggesting they are mainly lightpolluted;(2) As for the proportion of potential ecological risk factors (E_(r)^(i)), the proportion of minor ecologicalrisk of three groups of La-Ce-Yb, Pr-Nd-Sm-Eu-Gd-Dy-Er and Tb-Ho-Tm in samples were 100%, >90% and>84.8%, respectively. Potential ecological risk index (RI) ranges from 25.43 to 1904, with an average of199.44, which means the soil is in a moderate ecological risk;(3) ΣREE, L_(REE), P_(N) and RI have the same spatialvariation law. It is confirmed that the accumulation of rare earth in the surface soil is mainly controlled bygranite weathering and hydrological conditions, and the mining development has limited influence on it. Inshort, the light soil rare earth pollution and little ecological risk in the area are safe and controllable.

关 键 词：土壤稀土 空间分布 风险评价 环境地质 锡矿区 湖南 

分 类 号：X53[环境科学与工程—环境工程] P66[天文地球—地质学]