【作者】 滕彦国；

【导师】 倪师军； 张成江；

【作者基本信息】 成都理工学院 ， 矿产普查与勘探， 2001， 博士

【摘要】 论文详细研究了攀枝花地区约900平方公里面积内土壤环境地球化学特征，确定了土壤环境地球化学基线，并建立了判别自然的和人为的环境影响的地球化学指标，在此基础上进行了重金属污染的环境地球化学分析。取得的创新性研究成果及认识如下： （1）通过扫描电镜分析、X射线衍射分析等确定了攀枝花地区昔格达组粘土主要为壤质破土和砂质壤土，昔格达组泥岩、泥灰岩及粉砂岩风化成土过程以机械破碎为主。 （2）地球化学基线是进行环境污染状况分析的基础。采用标准化方法、统计分析方法、地层对比方法确定了攀枝花地区昔格达组粘土重金属元素的环境地球化学基线，结果表明，不同深度及采用不同方法确定的地球化学基线存在着一定的差异。 （3）地质累积指数方法是评价土壤及沉积物中重金属人为污染的有效方法之一，地质累积指数越大，遭受的污染越严重。该区土壤表层（A层）中Cr、Co、Ni、Cu、Zn、As、Cd、Pb等元素的地质累积指数接近于0，各元素的污染级别大多为1级和2级，属无污染和轻微污染，仅个别元素和个别样点为3级和4级，为中度污染和强污染。攀枝花地区土壤A层土壤各元素污染级别（据地质累积指数）的大小顺序为：Cd＞As＞Zn＞Pb＞Co＞Ni＞Cr＞Cu，C层土壤各元素污染级别的大小顺序为：Ni＞Zn＞Pb＞Cd＞As＞Co＞Cu＞Cr。另外，选择不同的地球化学基线对地质累积指数有一定的影响。 （4）攀枝花地区荒草地表层土壤中As、Cd、Co、Cr、Cu、Ni、Pb、Ti、V、Zn的富集团子在宝顶煤矿、太平煤矿、格里坪、攀矿、尾矿坝等工矿区较大，表明上述地区人为环境影响较重，而在同一样点，农田中的富集因子较荒草地土壤中大，表明农田中各元素受到的人为影响更大。另外，选择不同的基线计算得到的富集因子有一定的差异。 （5）攀枝花地区荒草地土壤重金属的污染程度分析表明，污染程度较高的地区主要分布在宝顶煤矿、太平煤矿、尾矿坝等工矿区。农田中表层土壤重金属元素含量水平与我国农田中重金属的环境质量Ⅱ级标准相比，没有超标，但宝顶煤矿、太平煤矿、尾矿坝、攀钢、攀矿等地污染略大。 （6）采用地质累积指数分析、富集因子分析和污染程度分析得到的攀枝花地区土壤重金属污染的信息基本一致。 （7）不同经济区的重金属污染特征表明：荒草地土壤重金属污染的轻重顺序为：煤矿区＞攀钢工业区＞电厂等其它工业区＞农业区＞城市居住区；农田土壤重金属污染的轻重顺序与荒草地的土壤相同。该区荒草地土壤重金属的污染元素组合可分为三组：As-Co-Cd，Cu-Pb-Ni，Cr-Zn。而农田中的污染元素组合在不同的土地利用类型区存在一定的差异。更多还原

【Abstract】 This thesis focuses its research on geochemical characteristics of soil environment in some region of Panzhihua of 900 square kilometers. At the same time, the author also determines geochemical baseline, and defines the geochemical indicators which are used to tell the influence of nature from that of human being on environment, on the basis of above, environmental analysis of heavy metal pollution is made. The main researching results are as follows: (1) With the use of Scan Electronic Microscope and X-ray diffraction analysis, it is determined that Xigeda formation clay of Panzhihua area is mainly composed of loamy sand and sandy loam, and that the main part of weathering pedogenesis of Xigeda formation petite, calcareous siltstone, and siltpelite is mechanical break. (2) A geochemical baseline for an element refers to its natural variations in concentration in the surficial environment and is the basis of environmental pollution analysis. With the use of normalization approach and statistically analyzing method, the environmental geochemical baseline of heavy metal elements such as As, Cd, Co. Cr, Cu, Ni, Pb, and Zn in topsoil (0-5cm ) and subsoil(3Ocm) of Panzhihua Xigeda formation clay is ascertained; at the same time, with the use of stratum comparison approach, the geochemical baseline of above elements in deep layer of Xigeda formation is also determined. It is shown that there exists some different among those geochemical baseline which is determined in different layer and in different approach. (3) The index of geoaccumulation is important parameter to assessing heavy metal pollution in soil and sediments. Through the Geoaccumulation Index calculation of elements such as Cr, Co, Ni, Cu, Zn, As, Cd, Pb in topsoil in Panzhihua region, it is shown that most elements are in contamination level of 1 to 2, uncontaminated/slightly contaminated; some elements are in contamination level of 2 to 3, slightly contaminated/moderately contaminated. According to the Geoaccumulation Index, the contamination degree from strong to weak in topsoil is: Cd> As> Zn> Pb> Co > Ni > Cr> Cu. Though the Geoaccumulation Index in deep stratum is greater than that in topsoil, the contamination level is roughly same, and the related order from strong to weak is: Ni > Zn> Pb> Cd> As> Co> Cu> Cr. In addition, selecting different geochemical baseline may influence the Index of Accumulation. (4) The Enrichment Factor of As, Cd, Co, Cr, Cu, Ni, Pb, Zn in uneven ground topsoil in Panzhihua region is greater in Baoding coal mine, Taiping coal mine, Panzhihua iron mine, Panzhihua smelting factory, Panzhihua tailing dam, which demonstrates the above regions are more seriously influenced by human activity, while at the same site, enrichment factor of farmland is greater than that of uneven ground, which shows that the elements in farmland is much influenced by human activity. (5) The total contamination degree of soil heavy metal in Panzhihua uneven ground is ?.09-?-2.35, most of parts is -2---2. The total contamination degree is greater than 0, which means that this region has been polluted, while the main polluted areas are centered on industrial and mining area such as Baoding coal mine, Taiping coal mine, Panzhihua iron mine, Panzhihua smelting factory, and Panhizhua tailing dam. The total contamination degree of heavy metal in topsoil of farmland is ?.97?-l .94, which is under更多还原