摘要
【目的】探究矿产资源集中区土壤砷(As)、钴(Co)和钒(V)背景值特征,并分析其主要环境影响因素,以期为区域土壤污染精准识别与管控提供科学支撑。【方法】选取四川南部的石棉(M)、汉源(H)、会东(D)、会理(L)和盐边(B)5个区县作为研究区域,系统采集并整合了231份表层(0~50 cm)土壤样品数据。基于“研究区尺度”和“县域尺度”双重视角,采用描述性统计和对比分析方法,构建土壤As、Co和V元素背景值;进一步结合相关性分析与随机森林模型,探讨海拔、坡度、土壤pH、有机质、电导率、阳离子交换量及机械组成等环境因素对元素背景值的影响。【结果】研究区尺度上,土壤As、Co、V元素背景值分别为8.77、16.01和106.17mg/kg;县域尺度上,3种元素背景值呈现显著的空间异质性,As背景值在H县最高(17.33 mg/kg),在B县最低(3.97 mg/kg);Co背景值在L县和B县相对较高;V背景值则在B县最高(164.97 mg/kg)。与全国及四川省背景值相比,除H县外,研究区As背景值普遍较低;Co背景值整体高于全国背景值,V背景值在D县、L县和B县均显著高于全国及四川背景值,最高可达全国背景值的2.00倍,呈现明显高背景特征。环境因素分析表明,阳离子交换量是影响Co和V背景值的关键因素,坡度对As背景值影响最为显著;土壤机械组成(黏粒与砂粒含量)也通过吸附作用对元素背景值产生重要影响。【结论】研究区土壤As、Co、V元素背景值具有显著的空间异质性,县域尺度较研究区尺度更能精确反映局部差异。土壤元素背景值主要受阳离子交换量、坡度及土壤机械组成等因素影响。
【Objective】To explore the background values of arsenic(As),cobalt(Co)and vanadium(V)in the soil of mineral resource concentration areas,and to analyze the main environmental influencing factors,with the aim of providing scientific support for the accurate identification and management of regional soil pollution.【Method】Five counties in southern Sichuan,including Shimian(M),Hanyuan(H),Huidong(D),Huili(L)and Yanbian(B)were selected as the study areas.A total of 231 surface soil samples(0-50 cm)were systematically collected and integrated.Based on the"regional scale"and"county scale"perspectives,the background values of soil As,Co and V elements were constructed using descriptive statistics and comparative analysis methods.By further integrating correlation analysis and random forest model,this study explored the influence of environmental factors such as altitude,slope,soil pH,organic matter,electrical conductivity,cation exchange capacity(CEC),and mechanical composition on the background values of these elements.【Result】At the regional scale,the background values of As,Co,and V elements were 8.77,16.01 and 106.17 mg/kg,respectively.At the county scale,the background values of the three elements showed significant spatial heterogeneity.The background value of As was the highest in H county(17.33 mg/kg)and the lowest in B County(3.97 mg/kg).The Co background values were relatively high in L and B Counties,and the V background value was the highest in B County(164.97 mg/kg).Compared with national and Sichuan provincial background values,except for H county,the As background values were generally lower,while the Co background values were overall higher than the national background values.The V background value was significantly higher than the national and Sichuan background values in D,L and B counties.It could reach up to 2.00 times the national background value,showing a distinct high-background characteristic.The analysis of environmental factors indicated CEC was the key factor influencing the background values of Co and V,and the slope had the most significant impact on the background value of As.Soil texture(clay and sand content)also had an important influence on the background values of elements through adsorption.【Conclusion】The background values of As,Co,and V elements exhibited significant spatial heterogeneity.The county scale was more capable of accurately reflecting local differences compared to the regional scale.The background values of soil elements were mainly influenced by factors such as CEC,slope,and soil texture.
作者
李洋涛
吴怡
邓思维
王文浩
何林玲
杨刚
LI Yangtao;WU Yi;DENG Siwei;WANG Wenhao;HE Linling;YANG Gang(Collage of Environmental Sciences,Sichuan Agricultural University,Chengdu 611130,China;Sichuan Academy of Eco-Environmental Sciences,Soil and Groundwater Pollution Prevention Research Institute,Chengdu 610046,China)
出处
《四川农业大学学报》
北大核心
2025年第6期1545-1553,1564,共10页
Journal of Sichuan Agricultural University
基金
四川省生态环境厅科技计划(2023HB02、2024HB01)
四川省生态环境科学研究院科技创新项目(ZX-2023106)。
关键词
矿产资源集中区
元素背景值
土壤
影响因素
mineral resource concentration area
background value
soil
influencing factors
