锑矿区土水界面污染流中重金属的空间分析

发布时间：2018-03-31 12:03

本文选题：GIS　切入点：空间分析　出处：《湖南科技大学》2015年硕士论文

【摘要】：随着人类文明的进步,工业发展进程越来越快,人类对矿产资源的需求和开采也日益增长,与此同时,在对矿产资源的开发过程中难免伴随着生态环境的恶化和对自然界的破坏,由此产生的重金属污染不容小视。人类的矿产开采活动把原本深埋于地下的金属矿石暴露于大气与地表上,通过降雨、径流、沉降等水文循环使得重金属元素扩散到河流、土壤、大气中,对生态环境造成污染,同时也对人类的生存环境构成威胁。本研究将以湖南省的冷水江市锡矿山锑矿区作为研究区,通过野外采样、调查、室内实验对样品中六种重金属(Sb、Zn、Cu、Ni、Pb、Cd)的含量进行测定,并引入地统计学分析方法研究矿区土水界面污染流中重金属的污染特征、重金属污染的空间结构特征并分析来源。1.对在降雨且形成地表径流的条件下采集的204个土水界面污染流样品中的重金属含量进行测定,经统计分析发现除了重金属Ni的最大值低于标准值以外,另外五种金属Sb、Zn、Cu、Pb、Cd的最大值都远远超过了标准值,分别是标准值的497.1、2.0、1.8、22.2倍。Sb的所有样本数据全部超标而且污染指数最高,Zn、Pb和Cd的一半样本超标,Ni的超标率为0。表明除了Ni以外研究区内其他五种重金属的污染程度比较严重,Cd污染指数较低,说明局部地区存在较严重的污染。2.对土水界面污染流中六种重金属元素的空间结构特征进行分析,得到了半变异函数的最佳拟合模型及模型参数,模型拟合效果较好,拟合模型的决定系数R2在0.721-0.976之间,块金值C0和基台值C+C0的比值范围为0.0767-0.559,表明六种金属元素具有较强的空间相关性。3.在GIS软件的ArcMap中对锑矿区土水界面污染流中六种重金属元素的空间分布进行插值绘图,结果表明研究区内土水界面污染流重金属Ni、Pb、Cd的污染分布比较相似,主要集中在南北两端和东部,而且居民生活、交通运输和工业活动是形成污染的主要原因。Sb的分布主要集中在中部,和矿山、冶炼厂的位置重合,说明研究区内矿业、工业活动是造成Sb污染的主要原因。Zn和Cu的污染分布比较相似,主要集中在南北两端和西部,位置与矿山、锌厂、居民区、交通繁忙区重合,说明这两种重金属来源比较广泛。4.除重金属Sb在研究区内是以倒置的“U”形分布以外,其他五种重金属元素都大致以“U”形分布。所以总体来说重金属Sb在中部的污染程度大于周边,而另外五种重元素则相反。
[Abstract]:With the progress of human civilization, the process of industrial development is getting faster and faster, and the demand and exploitation of mineral resources are also increasing. At the same time, In the process of exploitation of mineral resources, the deterioration of ecological environment and the destruction of nature are inevitable. The heavy metal pollution caused by this is not to be ignored. Human mining activities expose metal ores buried deep in the ground to the atmosphere and the surface. Heavy metal elements spread to rivers through hydrological cycles such as rainfall, runoff, sedimentation and so on. Soil, atmosphere, pollution to the ecological environment, but also pose a threat to human survival environment. This study will take Lengshuijiang City, Hunan Province Xikuangshan antimony ore area as a research area, through field sampling, investigation, The contents of six heavy metals in the samples were determined in laboratory, and the pollution characteristics of heavy metals in the soil-water interface of mining area were studied by using geostatistical analysis method. The spatial structure characteristics of heavy metal pollution and its source. 1. The contents of heavy metals in 204 soil-water interface polluted stream samples collected under the condition of rainfall and formation of surface runoff were determined. The statistical analysis shows that the maximum value of the heavy metal Ni is lower than the standard value, and the maximum value of the other five metals, SB ~ (2 +) Zn ~ (2 +) Cu ~ ((2 +)) Pb ~ (2 +) ~ (2 +), All the sample data of 497.1 / 2. 0 / 1. 8 / 2. 2 times of Sb were all in excess of the standard, and the ratio of exceeding the standard was 0 for half of the samples with the highest pollution index (Zn, Pb and CD), which indicated that the pollution ratio of the other five heavy metals in the study area except Ni was higher than that of the other five kinds of heavy metals. More serious pollution index of CD is lower, The spatial structure characteristics of six heavy metal elements in soil-water interface pollution flow are analyzed, and the best fitting model and model parameters of semi-variogram are obtained, and the fitting effect of the model is good. The determination coefficient R2 of the fitting model is between 0.721-0.976, The ratio range of block gold value C 0 and base value C C 0 is 0.0767-0.559, which indicates that the six metal elements have strong spatial correlation .3.The spatial distribution of six heavy metal elements in soil-water interface pollution stream of antimony ore area is interpolated in ArcMap of GIS software. The results show that the pollution distribution of heavy metal Ni PbN CD at the soil-water interface in the study area is similar, mainly concentrated at the two ends of the north and the south and in the east, and the residents live in the same area. Traffic, transportation and industrial activities are the main causes of pollution. The distribution of Sb is mainly concentrated in the central region, coinciding with the location of mines and smelters, indicating the mining industry in the study area. Industrial activity is the main cause of SB pollution. The pollution distribution of Zn and Cu is similar, mainly concentrated at the two ends of north and south and west. The location coincides with that of mines, zinc factories, residential areas, and areas with heavy traffic. The results show that the two heavy metals come from a wide range of sources, except for the inverted "U" shape distribution of the heavy metal SB in the study area. The other five heavy metals are distributed in the "U" shape, so the pollution degree of SB in the middle is higher than that in the periphery, while the other five heavy elements are opposite.
【学位授予单位】：湖南科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：X753;X53;X52

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