Mobility and speciation of Cd,Cu,and Zn in two acidic soils affected by simulated acid rain

Through a batch experiment, the mobility and speciation of heavy metals(Cd, Cu, Zn) in two acidic forest soils from Hunan Province were studied. The results showed that the release and potential active speciation of Cd, Cu, and Zn in the tested contaminated red soil(CRS) and yellow red soil(CYRS) increased significantly with pH decreasing and ion concentrations increasing of simulated acid rain, and these effects were mainly decided by the pH value of simulated acid rain. Cd had the highest potential nsk on the environment compared with Cu and Zn. Cd existed mainly in exchangeable form in residual CRS and CYRS, Cu in organically bound and Mn-oxide occluded forms, and Zn in mineral forms due to the high background values.     

Release behavior of copper and zinc from sandy soils

The concentrations and chemical forms of copper(Cu) and zinc(Zn) in surface soils directly influence the movement of Cu and Zn. In this study, thirteen sandy soil samples with a wide range of total Cu and Zn concentrations were collected for evaluating the relationships between Cu and Zn release and extraction time, ratio of soil to water, pH and electro;yte types. The results indicated that Cu released in batch extraction that represents long-term leaching was mainly from exchangeable, and carbonate bound Cu fractions, and Zn released in the batch extraction was mainly from its carbonate bound fraction. However, the Cu and Zn leached from the soils using the column leaching that represents short-term leaching were mainly from their exchangeable fractions. Soil column leaching at different pH values indicated that the amounts of leached Zn and Cu were greatly affected by pH. The Cu and Zn release experiments with varying extraction times and ratio of soil to water suggest that long-term water-logging in the soils after rain may increase contact time of the soils with water and the release of Cu and Zn to water from the soils, and total amounts of Cu or Zn released from the soils increase, but the Cu or Zn concentration in the surface runoff decrease with increasing rainfall intensity. The increased Ca concentration in soil solution increased stability of organic matter-mineral complexes and might decrease the dissolution of organic matter, and thus decreased the release of Cu-binding component of organic matter. However, high concentration of Na in the soil solution increased the dispersion of the organic matter-mineral complexes and increased dissolution of organic matter and the release of Cu from the soils.     

Effect of two biogas residues’ application on copper and zinc fractionation and release in different soils

Biogas residue (BR) is widely used as a new green fertilizer in agriculture in China. However, it often contains a high concentration of heavy metals so its application should cause our concern. An incubation experiment was conducted to study the risk of pig biogas residue (PBR) and chicken biogas residue (CBR) application on Liuminying soil (LS) and Yixing soil (YS). The soils were incubated for one, three and six months with 0, 2%, 4% and 6% addition of BRs. According to BCR extraction results, the PBR and CBR applications induced an increase in the concentration of exchangeable fraction of Zn. As for the concentration of exchangeable fraction of Cu, an increase was only observed in the treatments with PBR application. The heavy metal binding intensity also showed a similar trend. With the PBR application, for the LS and YS, the highest concentrations of exchangeable Zn increased 3.6 and 9.5 times, respectively, while the exchangeable Cu was increased by 52.6% and 187.1%. Dissolved organic carbon was the limiting factor for the exchangeable Cu while the exchangeable Zn was controlled by soil pH. PBR presented more agricultural risk than CBR when used as fertilizer. Meanwhile, BRs were more adaptable to LS than YS according to the heavy metal release results.     

洞庭湖南缘农田土壤重金属特征及源解析

基于网格布点法于2020年4～8月在洞庭湖南缘农田中采集了1 589件表层土壤样品,采用ICP-MS、 ICP-OES、 HG-AFS和ISE方法测定土壤中As、 Cd、 Pb、 Cu、 Zn、 Ni、 Cr、 Hg元素含量及pH,重点研究了区内土壤重金属含量、潜在生态风险、空间分布特征及其来源解析.结果表明,土壤重金属ω(Zn)、ω(Cr)、ω(Pb)、ω(Cu)、ω(Ni)、ω(As)、ω(Cd)和ω(Hg)平均值依次为：118.18、 82.21、 52.1、 33.76、 32.81、 18.25、 0.42和0.13 mg·kg^-1.各重金属均处于中、高度变异,土壤以弱酸性为主,pH介于3.96～7.90之间,Hg和Cd存在较高的生态风险.各重金属元素空间分布规律均呈西南高东北低的趋势.采用PMF和PCA方法对8种重金属元素进行来源解析及贡献率计算,PMF结果表明,研究区土壤重金属来源贡献率依次为：农业活动源(36.98%)、自然源(32.94%)、水土交换源(17.05%)和大气干湿沉降源(13.03%),而PCA结果表明研究区土壤重金属主要来源于农业...     

广东大宝山铁多金属矿废水对河流沿岸土壤的重金属污染

粤北大宝山铁多金属矿开发活动产生的选冶废水未经处理直接排放到横石河水中,给横石河流域沿岸环境带来了严重的危害. 对沿岸土壤剖面重金属总量和形态的分析表明, Pb、Zn、Cd、Cu等均存在不同程度的污染. 其中, 以Cd污染最为严重, Pb、Zn也达到中度污染至强污染. 河流水体和土壤的pH值对金属总量和可交换态离子浓度有一定程度的影响. 土壤中金属总量、金属可交换态含量随着土壤酸度的变化出现相应的变化. 在地处下游地势低平污染严重的上坝村, 农田表层土Pb、Zn、Cd、Cu的总量分别达到257.762, 350.235, 5.083和186.901　mg·kg^-1, 分别超出国家标准的1.03倍、1.75倍、16.9倍和3.7倍, 且污染渗透至土壤的深层, 生态环境受到严重的潜在危害.     

硫脲对酸性红壤 pH值与金属元素有效性的影响

通过实验室模拟,研究了不同浓度硫脲与尿素配施后,对酸性红壤的pH值及其金属元素有效性的影响.结果表明,土壤施加尿素后,其pH值有先升高后逐渐下降的趋势,而硫脲与尿素配施后,其pH值的下降趋势会受到抑制,尤其是当硫脲浓度达到5.0 mmol·kg-1时,土壤pH由最初的4.65上升到6.50以上,并在实验的中后期一直维持在6.0以上.硫脲和尿素配施后,Cu的有效态含量受硫脲浓度的影响较小,Zn、Al的有效态含量随着硫脲浓度的升高而降低,Mn的有效态含量在高浓度硫脲下,其含量保持在一个较高的水平,达到110 mg·kg-1以上.对于Cu、Zn和Al来说,在不同浓度硫脲和尿素配施后,其有效态含量与土壤的pH值呈现出明显的负相关.而对于Mn来说,在单施尿素的情况下,其有效态含量与土壤的pH值呈现出负相关,而在施入硫脲后,其有效态含量与土壤pH并没有呈现出明显的规律性.同时,研究结果还表明酸性红壤Al有效性随着土壤pH的升高而减小,当硫脲与尿素配合使用时,短期内土壤pH上升得更高,从而使得酸性红壤中Al的有效性减小.在硫脲和尿素配施后,土壤中Mn的有效态含量并不简单地取决于土壤的pH值,由于硫脲对Mn的络合作用和氧化还原作用,其含量受到土壤pH值和硫脲的共同影响.     

Remediation of copper polluted red soils with clay materials

Attapulgite and montmorillonite were utilized to remediate heavy metal polluted red soils in Guixi City, Jiangxi Province, China. The e ects of clay minerals on availability, chemical distribution, and biotoxicity of Cu and Zn were evaluated. The results provided a reference for the rational application of clay materials to remediate heavy metal contaminated soils. From the sorption experiment, the maximum adsorbed Cu2+ by attapulgite and montmorillonite was 1501 and 3741 mg/kg, respectively. After polluted red soil was amended with attapulgite or montmorillonite and cultured at 30 and 60 days, soil pH increased significantly compared to the control. An 8% increase in the amount of montmorillonite in soil and 30 days incubation decreased acid exchangeable Cu by 24.7% compared to the control red soil. Acid exchangeable Cu decreased with increasing amounts of attapulgite and montmorillonite, with best remediation e ect reached at a dose of 8%. Results also showed that the Cu poisoning e ect on earthworms was reduced with the addition of attapulgite and montmorillonite. Montmorillonite showed the best e ect, with the addition of a 2% dose the mortality of earthworms decreased from 60% to zero compared to the control. Our results indicated that the bioavailability of Cu in soils was reduced more e ectively with the application of montmorillonite than attapulgite.     

长江中游典型湖泊沉积物重金属分布特征、生态风险评估及溯源

集中采集洞庭湖、洪湖和赤湖表层沉积物样品并检测其中10种重金属含量,使用地理信息系统表征空间分布,利用地累积污染指数法（I_geo）、富集因子法（EF）和潜在生态风险指数法（RI）协同评估重金属积累的潜在风险,并利用相关性分析（Pearson）和主成分分析（PCA）溯源.结果表明,Cd元素的污染状况和潜在生态风险最为严重,东洞庭湖、洪湖和赤湖中ω（Cd）的平均值分别为2.85、1.59和3.57 mg·kg^-1,分别是对应省份土壤背景值的25.87、11.36和37.58倍,均超出风险筛选值（0.6 mg·kg^-1）,其中赤湖超出风险管制值（3.0 mg·kg^-1）.除Cd外,洪湖中的As值得关注,赤湖中的Cu、As、Zn和Pb都不容忽视.三湖的潜在生态风险排序为：赤湖（RI=1 127）>东洞庭湖（RI=831）>洪湖（RI=421）.重金属来源主要是工矿业冶采、农业生产和水产养殖等,部分重金属（Mn和Cu）为自然源.研究对长江中游典型湖泊沉积物重金属防控具有重要意义.     

模拟酸雨下土壤中铜、镉行为及急性毒性效应

本文论述模拟酸雨下红壤、黄棕壤和黑土中Cu、Cd行为及急性毒性效应.试验表明:(1)模拟酸雨对添加性土壤Cu、Cd的淋溶有一定的影响,随着降水酸度的增大,土壤中Cu、Cd的淋出量增加,但增加的程度与土壤类型、添加金属的浓度和种类有关,相同酸度下,红壤中Cu、Cd的淋出量远大于黄棕壤和黑土,淋出率随着沉降酸度而改变的程度也最显著,酸雨对黑土中Cu、Cd淋溶影响最小.Cd对酸雨淋溶的敏感性大于Cu.(2)模拟酸雨对土壤中Cu、Cd形态影响较为明显,随着酸雨pH的降低,黄棕壤和黑土中部分Cu、Cd形态明显地向着交换态转化,红壤中部分Cu、Cd形态明显地向着水溶态转化.(3)模拟酸雨对土壤中Cu、Cd的生物毒性影响很大,但这种影响同时又受土壤类型相当大的制约,红壤中毒性影响最大,黑土中毒性影响最小,表明三类土壤的抗酸能力顺序为黑土>黄棕壤>红壤.     

贵州百花湖沉积物重金属稳定性及潜在生态风险性研究

为研究贵州高原河道深水湖泊百花湖的重金属污染状况,以该湖泊10个采样点的表层沉积物为研究对象,测定了Hg、Cd、As、Pb、Cu、Zn、Cr7种重金属的含量,并对其中5种重金属(Cd、Pb、Cu、Zn、Cr)的存在形态和稳定性进行了研究.结果表明,Cu、Zn、Cr在百花湖沉积物中各形态的平均含量变化趋势为:残渣态>有机结合态>铁锰氧化物结合态>碳酸盐结合态>可交换态,Cd为残渣态>可交换态>有机结合态>铁锰氧化物结合态>碳酸盐结合态,Pb为残渣态>铁锰氧化物结合态>有机结合态>碳酸盐结合态>可交换态,几种重金属平均浓度均在临界效应浓度值和必然效应浓度值之间.Cd、Pb、Cu、Zn和Cr5种重金属元素稳定度变化范围依次为:6%～35%、8%～23%、8%～11%、8%～18%、2%～14%,稳定性依次为:Cr>Zn>Cu>Cd=Pb,这些元素基本处于稳定-中等稳定状态.最后,分别以1990年贵州省土壤重金属背景平均值和本次采样周边土壤背景值为基本值,对百花湖沉积物进行生态风险性评价.结果发现,百花湖已经处于中等-很强水平的生态危害程度,说明百花湖水体可能已受到重金属的严重污染,但其稳定性可能推迟或减弱其有效生态危害性,但仍有必要加强该湖泊水体中重金属的监测工作.     

深圳市不同土类的重金属环境背景值与理化性质特征

城市土壤环境背景值特征研究可为制定区域土壤背景值标准提供科学依据.为摸清深圳市不同土类重金属（Cr、Cu、Zn、Ni、Pb、Co、V、Cd和Hg）的环境背景值特征,探究重金属环境背景值与土壤理化性质的关系,在全市布设500个土壤背景点位,采用多点增量法采集500个土壤表层（0~20 cm）样品,赤红壤405个,红壤77个,黄壤18个.结果表明：①红壤重金属的背景值整体偏低,赤红壤Cr、Ni、Co和V以及黄壤Cu、Zn、Hg、Pb和Cd的背景值高于其他土类;3种土类中Cr、Cu、Zn、Ni、Co和V的背景值比全国"七五"背景值低,Cd和Hg背景值与全国"七五"背景值较为接近,Pb背景值高于全国"七五"背景值;②9种重金属背景值的空间分布规律差异较大,Pb、Zn和Co呈明显的地带性分布格局,Cr、Cu、Ni、V、Cd和Hg表现为点状分布格局;③将不同土类重金属背景值与理化性质参数进行相关性分析,发现赤红壤重金属背景值与理化性质的相关性最为显著;④通过逐步回归分析,将赤红壤中重金属背景值与理化性质参数的关系进行定量化表达,探明影响赤红壤重金属背景值的理化性质参数依次为机械组成、pH、有机质和阳离子交换量.     

长江水系表层沉积物重金属污染特征及生态风险性评价

对2007年采集的长江水系表层沉积物中的9种重金属(Cr、Co、Ni、Cu、Zn、Pb、Cd、As和Hg)含量进行了分析.结果表明,沉积物中除了重金属Cr、Co、Ni外,Cu、Zn、Pb、Cd、As和Hg的含量都明显高于20世纪90年代调查结果.主成分分析(PCA)结果表明,前3个主成分的累积贡献率达到86.75%,表明了重金属的3种主要来源,分别为采矿与工业排污、岩石的自然风化与侵蚀和城市电镀工业废水与自然源.地累积指数和富集因子评估结果同时显示,长江水系表层沉积物中未受Cr、Co和Ni的污染,Cu、Zn、As和Hg受轻度污染,而Cd和Pb的污染最大.Hakanson生态风险指数法对沉积物中重金属的生态风险评价表明,各重金属单因子生态危害程度为CdHgAsZnPbCuCoNiCr.综合潜在生态指数表明,在61个位点中,中等生态危害的样点占36%,有3个位点属于强生态危害范畴,即长江干流重庆段、支流资水洞庭湖入口和信江位点;而支流湘江衡阳段、湘江株洲段、湘江洞庭湖入口、洞庭湖和安徽顺安河位点为极强生态危害范畴.     

洞庭湖表层沉积物重金属赋存形态及生态风险评价

为深入了解洞庭湖沉积物重金属污染现状及生态风险,采用欧共体物质标准局提出的BCR提取法分析29个表层沉积物中Cd、Cr、Cu、Pb和Zn的赋存形态,并应用基于重金属形态的RSP（ratio of secondary phase and primary phase,次生相与原生相分布比值法）和RAC（风险评价指数法）评价了沉积物重金属的污染程度与生态风险.结果表明:全湖范围内,Cd主要以弱酸溶解态为主,Cr主要以残渣态和可还原态为主,Cu以残渣态和可氧化态为主,Pb以可还原态和残渣态为主,Zn以残渣态和弱酸溶解态为主;RSP评价结果显示,Cd在全湖范围表现为重度污染,Pb总体表现为中度污染,但在湘、资、沅、澧"四水"入湖口以及东洞庭湖几个采样点表现为重度污染,Cr、Cu和Zn处于轻度污染和清洁水平;RAC评价结果表明,全湖范围内5种重金属生态风险排序依次为Cd > Zn > Pb > Cu > Cr,Cd表现为高等风险,Cu、Pb和Zn表现为中等风险,而Cr表现为低等风险.研究显示,在研究沉积物重金属总量基础上进行重金属形态分析,有助于深入了解重金属对环境的危害.      

关中平原畜禽粪便重金属农用风险估算

通过在关中平原畜禽养殖集中的县区采集畜禽粪便和饲料样品,测定其中Cr、Cu、Pb、Zn等重金属元素含量,以评估施用畜禽粪便造成的土壤重金属累积速率和安全使用年限.结果表明,牛粪、鸡粪、猪粪样品中Cr超标率分别为7.69%、4.35%和8.00%,而猪粪中Cu、Zn超标率分别达到76.00%和8.00%.饲料样品中Cu、Zn含量高于Cr、Pb含量,且与畜禽粪便Cu、Zn含量呈极显著正相关关系,结合主成分分析可知,畜禽粪便中Cu、Zn主要来源于饲料.形态分析结果显示,畜禽粪便中Cu、Zn的有效性很高,尤其是鸡粪中Cu、Zn的有效态含量最高.若畜禽粪便施用量保持在当前水平,则施用畜禽粪便24.4~131.0年和69.7~91.9年后,大棚土壤中Cu、Zn含量即可从土壤背景值分别达到安全临界值,因此,畜禽粪便农用时,不仅要控制其施用量,还应适当减少饲料中Cu、Zn添加量.     

几种母质土壤及糙米中重金属含量差异性初探

砂页岩、河流冲积物、洪积物、第四纪红土和花岗岩是桂东北地区农业土壤的主要成土母质.本文对这5种成土母质的稻田土壤及糙米中的 Cu、Zn、Pb、Cd、Ni、As、Cr、Hg 8种重金属元素含量的差异性进行了检验,对这5种母质的土壤糙米重金属元素含量相关性进行了分析.结果表明,多数元素在多数母质及糙米中的含量差异不显著;除 Cu在第四纪红土—糙米、Pb 在砂页岩—糙米中的含量相关性达显著水平外,其它的母质—糙米中重金属含量相关不显著.     

大宝山矿区污染水体中重金属的形态分布及迁移转化

对受广东大宝山矿区矿山废水排放污染的横石河水体中的过滤水、悬浮物和沉积物中重金属的污染分布特征及其迁移转化进行了系统地研究.结果表明:该水体的环境污染是以Cu,Zn,Cd和Pb则为主的多金属复合污染,综合污染指数(PI)为2.23～18.11,重金属Cu,Zn,Cd和Pb的溶解态质量浓度分别达13.82,50.83,0.103和2.91 mg/L;Cu,Zn,Cd和Pb的溶解态、悬浮态及总量沿河流断面呈相似的空间分布规律,而As则略有不同,但都是沿水流方向逐渐降低的;由于受低pH的影响,水体中As主要以细微颗粒物悬浮态为迁移载体,而Cu,Zn,Cd和Pb则以水溶态为主要迁移方式; 沉积物中5种重金属元素都以残渣态为主要存在形态,Cd和Pb的可交换态及Cu和Zn的有机态含量很高,说明这4种元素对环境都有一定的潜在威胁性.      

Risk assessment of heavy metal contaminated soil in the vicinity of a lead/zinc mine

Heavy metal contamination of soils through anthropogenic activities is a widespread and serious problem confronting scientists and regulators throughout the world. In this study we investigated the distribution, chemical species and availability of lead, zinc, cadmium and copper in nine surface（0 to 20 cm） soils from near an abandoned lead/zinc mine tailings located in Shaoxing, Zhejiang, China. Total heavy metal contents ranged from 5271 to 16369 mg/kg for Pb, 387 to 1221 mg/kg for Zn, 3.0 to 9.3 mg/kg for Cd and 65 to 206 mg/kg for Cu. In general, all heavy metals exceeded China National Standards for Soil Environmental Quality of Heavy Metals by a factor of 3-65 times. Comparison of the heavy metal concentrations（Pb, Zn, Cd and Cu） with clay content revealed a strongly significant relationship while significant relationship（ P 〈 0.001 ） was also obtained between Cd ＋ Zn and Pb ＋ Cu. Solid phase speciation of the soils using Tessier procedure showed that the heavy metals were distributed in the order： residual 〉〉 organically complexed-Fe-Mn oxides occluded 〉 carbonate bound 〉 exchangeable 〉 water soluble. In the organic matter fraction, the ratio of Pb（29.1% ） to its total concentration in the soils was higher than those of Zn（4.70% ）, Cd（3.16% ） and Cu（9.50% ）. The percentages of the water soluble and the exchangeable fractions of Pb（1.80% ） and Cd（2.74% ） were markedly greater than those of Zn（0.10% ） and Cu（0.15% ）, suggesting that Pb and Cd are relatively more mobile and hence more toxic in the contaminated soils. Strongly significant relationships between H20-Pb, H20-Zn and H20-Cu, strong positive correlations between H20-Pb, H20-Zn, H20-Cu and organic matter in soil were found. The content of H20-Pb, H20-Zn, H20-Cu was negatively correlated with pH values. The similar negative relationships between pH values and exchangeable heavy metals were also recorded. It is suggested that increasing soil pH or liming the soil could decrease bioavailability of heavy metals in the soil.     

畜禽粪便有机肥中Cu、Zn在不同农田土壤中的形态归趋和有效性动态变化

通过土壤培养试验,研究了不同畜禽粪便有机肥中重金属Cu、Zn在不同农田土壤中的形态归趋和有效性动态变化过程,为合理确定由畜禽粪便有机肥带入农田土壤的重金属负荷,科学评价畜禽粪便有机肥中重金属进入土壤后的生态风险提供理论依据.结果表明,土壤中施用畜禽粪便有机肥后,酸性土壤p H值升高,而石灰性土壤p H值降低.施用鸡粪后6个月内,有效态Cu含量在2种土壤中显著低于等量Cu无机盐处理,而有效态Zn含量则与等量Zn无机盐处理无显著差异;施用猪粪后6个月内,有效态Cu和Zn含量在2种土壤中均与等量Cu和Zn无机盐处理无显著差异.形态归趋研究表明,通过畜禽粪便有机肥进入土壤中的Cu和Zn在土壤中主要以交换态、碳酸盐结合态、铁锰氧化物结合态以及有机结合态的形式存在,且畜禽粪便有机肥的来源不同,各形态Cu和Zn在不同土壤中所占比例不同.土壤中施用畜禽粪便有机肥6个月时,Cu和Zn交换态以及铁锰氧化物结合态所占比例低于等量Cu和Zn无机盐处理,而有机结合态所占比例高于等量Cu和Zn无机盐处理,其它形态与无机盐处理无显著差异.     

洞庭湖沉积物不同形态氮赋存特征及其释放风险

为了揭示湖泊沉积物中氮的空间分布特征及其释放风险,采用连续分级提取法研究了洞庭湖表层沉积物中EN(可交换态氮)、HN(酸解态氮)及NHN(非酸解态氮)的赋存特征;同时,结合BN(生物可利用态氮)的含量和释放通量的大小,探讨了各形态氮对BN的贡献及与释放通量的相关关系. 结果表明,受水动力和湖盆地形的影响,沉积物中各形态氮含量空间差异较大. 全湖w(TN)在735.91~2846.51mg/kg之间,平均值为1371.85mg/kg,东洞庭湖、西洞庭湖、南洞庭湖、洞庭湖出口w(TN)的平均值分别为1513.43、1173.14、1262.76和1363.31mg/kg. 从各形态氮含量占w(TN)的比例来看,w(HN)最高,平均占66.74%;其次是w(NHN),平均占21.46%;w(EN)最小,仅占11.80%. 东洞庭湖、西洞庭湖、南洞庭湖、洞庭湖出口w(BN)的平均值分别为189.31、170.16、152.87和139.51mg/kg,其值大小主要受w(EN)和w(HN)的影响. 东洞庭湖、西洞庭湖、南洞庭湖、洞庭湖出口沉积物中NH₄+-N释放通量的平均值分别为6.32、7.03、7.78和146.96mg/(m2·d),沉积物中NH₄+-N释放通量主要受EN控制,其中尤其受可交换态NH₄+-N的控制,而沉积物中的HN和TN尚不是影响沉积物氮释放的主要因素.      

滇西地区土壤重金属来源解析及空间分布

以滇西重金属地质高背景区为研究区,系统采集了4193件表层土壤样品,分析测试了As、Cd、Cr、Cu、Hg、Ni、Pb和Zn 8种重金属元素的含量,综合运用相关分析、主成分分析和单因素方差分析等经典统计方法探讨了土壤重金属来源和土壤重金属含量与成土母质、土地利用方式之间的关系,并利用地统计方法对重金属的空间分布特征进行了分析.结果表明：①研究区8种重金属含量平均值均超过全国土壤背景值,但是低于农用地污染风险筛选值;与云南省土壤背景值相比,As、Cd、Cu、Ni、Pb和Zn含量平均值与云南省背景值相当,Hg和Cr的平均含量分别是其背景值的2.35和1.60倍,土壤重金属存在不同程度累积现象.②Cr、Cu和Ni主要受成土母质的控制;Cd、Zn和Pb主要受人类活动影响,人为来源主要为铅锌矿开采选冶、交通运输和煤炭燃烧,Cd、Zn在一定程度上受成土母质的影响;As和Hg以人为来源为主,受汞矿采选、农业活动及煤炭燃烧的影响.③不同成土母质和土地利用方式的土壤中重金属含量差异显著.Cd、Cr、Cu、Hg和Ni在沉积岩母质区土壤中平均含量最高;草地中As、Cd、Cr、Cu、Hg、Ni、Zn平均含量最高.④Cu、Ni、Cr高值区与沉积岩母质区及区内分布的铜矿和铁矿空间耦合性良好;Pb、Cd和Zn的高值区与区内的铅锌矿分布范围基本一致;As和Hg高值区与区内汞矿等热液型金属矿的分布具有较高的空间一致性,在人类活动密集地区也呈高背景分布.