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题名	乌鲁木齐城区积雪不溶颗粒物及其痕量金属的空间变异特征
作者	李小兰
学位类别	硕士
答辩日期	2015
授予单位	中国科学院大学
授予地点	北京
导师	姜逢清
关键词	痕量金属 城市积雪 空间分布 空间自相关 乌鲁木齐
学位专业	理学硕士
中文摘要	本文利用2012年1月、2月以及2013年1月在乌鲁木齐城-郊区采集的总共195个积雪样品，采用电感耦合等离子体/质谱分析法（ICP-MS）分析了积雪不溶颗粒物中的11种痕量金属元素。根据积雪深度与密度数据，应用空间克里格插值法分析了乌鲁木齐城郊冬季积雪深度与密度的空间分布。基于测得的11种金属浓度，应用克里格空间插值法分析了2013年1月中旬积雪不溶颗粒及其痕量金属的空间分布特征；利用空间自相关分析方法辨识了积雪不溶颗粒物中痕量金属的空间热点区域；应用多元变量分析法和富集因子法对积雪不溶颗粒物中金属来源做了分析；采样污染指数法、生态风险指数法等初步评价了积雪不溶颗粒物中重金属污染物的健康风险。得出的主要结论如下：（1）乌鲁木齐城-郊冬季积雪深度与密度存在显著地区域分布差异及变化特征。整个冬季位于城东北部的米东石化工业园区积雪均较深，主城区内部又存在不同下垫面下积雪较多的区域。（2）Mn、Cu、Zn、Be、V、Cr、Co、Ni、Cd、Pb和U的平均含量分别为528.86、93.91、867.85、73.55、57.11、17.36、174.38、2.88、74.5和4.54 毫克/千克。除Mn、V、Cr和Co外，其余7种痕量金属的平均含量都高于背景值。痕量金属污染评价显示，大部分区域的痕量金属综合污染指数（IPI）值都在5以上，达到了严重污染水平。除Be、Cd、V和U外，其它金属从城市中心到近郊呈逐渐减少的趋势。在主城区、中心商业区等交通量大的区域，Cu、Ni、Pb、Mn和Zn的含量较高；在热力公司附近，Mn、Zn、Pb、Be的含量较高；而在工业分布较集中区域，Mn、Zn、Pb、Ni、Cu和Cd的含量较高。除元素Cd外，主城区中央区域都存在Mn、Cu、Pb、Zn和V的“高-高”热点；西北部是Cu、Pb、Zn、V和Cd的“高-高”热点区；主城区东部包含了Mn、Pb和Zn的几个热点；而城区东北角主要为V和Cd的热点区。（3）Ni、Cd、Pb、Cu和Zn的富集因子平均值大于3，表明其受严重的人为污染影响；U的富集因子在1到3之间，表明其受人为源的影响也较大；Mn、Be、V和Cr富集因子平均值小于1，其受自然源的影响较大。V、Cr和Co的主要来源是自然源；Pb、Be、U、Cu和Zn的主要来源是交通源和部分工业源；而Mn主要来自混合源。（4）Mn、Cu、Zn、Be、V、Cr、Co、Ni、Cd、Pb和U的非致癌综合风险值分别为5.08E-03、2.25E-03、2.69E-03、1.28E-03、1.01E-02、1.82E-02、4.23E-02、9.02E-03、3.14E-03、2.06E-02和8.52E-03。11种痕量金属的非致癌综合风险值小于1，为安全水平；Ni、Cd、Cr、Be和Co的致癌风险值分别为6.94E-09、8.61E-10、1.14E-07、6.83E-10和8.06E-09，均低于可接受的水平（10-6）。
英文摘要	A total of 195 snow samples were collected in January 2012，February 2012 and January 2013 in the city of Urumqi, capital of the Xinjiang Uygur Autonomous Region in northwest China. Contents of eleven trace metals (i.e. Mn, Cu, Zn, Be, V, Cr, Co, Ni, Cd, Pb and U) were analyzed by using Inductively Coupled Plasma–Mass Spectrometry (ICP–MS). The spatial variation of snow cover depth and density was analyzed by using Ordinary Kriging interpolation methods. Based on data of 11 trace metal concentrations, spatial distribution of trace metals were also investigated by Kriging interpolation procedure. Locations of pollution hotspots of these metals were found with the spatial autocorrelation analysis. And, their pollution sources were also analyzed by multivariate analysis and enrichment factor analysis. The health risk of heavy metals in insoluble particulate matters in snow was preliminarily evaluated. The main conclusions are as follows. 1. Snow cover depth and density between urban and suburb had significant spatial difference. Snow cover around the Midong petrochemical Industrial Park was thicker than the other parts in winter. Furthermore, the snow cover was different at various underlying surfaces inside the downtown areas. 2. The mean contents of Mn, Cu, Zn, Be, V, Cr, Co, Ni, Cd, Pb and U for all samples were 528.86, 93.91, 867.85, 73.55, 57.11, 17.36, 174.38, 2.88, 74.5 and 4.54 mg/kg, respectively. Except for Mn, V, Cr and Co, the mean contents of other seven metal pollutants were larger than their background values. Based on contamination assessment of the metals, it can be found that most of the urban area was seriously polluted with the integrated pollution index (IPI) above 5. Except for Be, Cd, V and U, the contents of other metals generally decreased from urban geometric center to suburb. Higher Cu, Ni, Pb and Mn were generally found in the city’s central commercial district; and higher Mn, Zn, Pb, Ni, Cu and Cd were found in intensive industrial zone; and higher Mn, Zn, Pb and Be were found near the heating power companies. Hotspot area (the highest contents) of Mn, Cu, Pb, Zn and V occurred in the central area of the city. Northwest area was characterized by partly hotspots of Cu, Pb, Zn,V and Cd, while there were few of hotspots of Mn, Pb and Zn. In addition, hotspots of V and Cd also occurred in the northeast corner of the city. 3. The pollution sources of the eleven trace metals were identified by using multivariate analysis methods, such as correlation analysis, principal component analysis (PCA) and cluster analysis (CA), combined with enrichment factor (EF). The results showed that mean EFs of Ni, Cd, Pb, Cu and Zn were higher than 3, implying a significant contribution of anthropogenic sources, while those of Mn, Be, V and Cr were lower than 1, showing a significant contribution of natural sources. The sources of V, Cr and Co were mainly of natural source；Pb, Be, U, Cu and Zn were mainly originated from industrial activities and road traffic; Mn may be from either natural source or anthropogenic source. However the sources of Cd were obviously different from those of other metal pollutants. Metallurgical plant, building materials, galvanization, plastic and industrial activities may be the major sources of Cd. 4. The human health risk induced by trace metals in insoluble impurities from urban snow was assessed based on the model developed by the US Environmental Protection Agency (US EPA). The results indicated that the hazard index of non-cancer risk of Mn, Cu, Zn, Be, V, Cr, Co, Ni, Cd, Pb and U was 5.08E-03, 2.25E-03, 2.69E-03, 1.28E-03, 1.01E-02, 1.82E-02, 4.23E-02, 9.02E-03, 3.14E-03, 2.06E-02 and 8.52E-03, respectively. The hazard indices of these metals are all less than 1, reflecting a “safe” level. The level of cancer risk of Ni, Cd, Cr, Be and Co was 6.94E-09, 8.61E-10, 1.14E-07, 6.83E-10 and 8.06E-09, respectively. The level of cancer risk is acceptable.
语种	中文
学科主题	环境科学
内容类型	学位论文
源URL	[http://ir.xjlas.org/handle/365004/14962]
专题	新疆生态与地理研究所_研究系统_荒漠环境研究室
作者单位	中科院新疆生态与地理研究所
推荐引用方式 GB/T 7714	李小兰. 乌鲁木齐城区积雪不溶颗粒物及其痕量金属的空间变异特征[D]. 北京. 中国科学院大学. 2015.

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