首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献，搜索用时 593 毫秒
1.
研究雄安地区土壤重金属和砷元素空间分布特征及其来源,对于支撑新区土地资源和环境管理具有重要意义。基于雄安新区土壤环境调查,运用地统计学方法和ArcGIS 技术分析模拟了土壤中As、Hg、Cd、Cu、Pb、Zn、Ni、Cr等8种元素空间分布特征,综合运用空间分析、多元统计学方法和正定因子矩阵模型解析这些元素的主要来源。结果表明:（1）区内土壤质量总体良好,4.35 %的土壤样品Cd和Cu含量超过农用地土壤污染风险筛选值,但均低于农用地土壤污染风险管控值;与河北省背景值相比,Cd、Cu、Pb、Zn和Hg存在不同程度中度和显著富集。（2）As、Cd、Cu、Pb、Zn、Ni、Cr含量呈现出由北部向南部逐渐增高的趋势,高值区主要分布在新区西南部;Hg元素分布分散,高值区主要分布在城镇及工业企业周边。（3）不同土地利用类型土壤剖面重金属和砷元素垂向分布受pH值、有机碳和铁铝氧化物等理化性质影响显著。（4）研究区土壤重金属和砷元素富集受人类活动影响明显,人为来源贡献率达67.12 %,Hg元素主要来源于人为排放的大气沉降富集,As元素富集受到废渣堆放和利用的影响,Cd、Cu、Pb和Zn元素富集受工业生产、污水灌溉以及尾气排放等活动影响。研究成果可为雄安新区合理制定土地资源开发利用和生态保护措施提供技术支撑。  相似文献   

2.
张春来  陆来谋  杨慧  黄芬 《中国岩溶》2022,41(2):228-239
采用GIS和地统计学研究土壤有机质（SOM）的空间分布、影响因素和预测是指导农业生产、环境治理和土壤碳储计量的重要手段。基于广西马山县北部岩溶区表层土壤 (0~20 cm)的441个SOM数据,建立普通克里格(OK)、回归克里格（RK）,以及结合辅助变量的地理加权回归克里格(GWRK)、残差均值（MM_OK）和中值（MC_OK）均一化克里格的5种模型,并比较其预测精度,旨在探讨岩溶区SOM制图中地统计学方法的适用性。结果表明:（1）SOM的变异系数为37.30%,属于中等空间变异;（2）岩溶区SOM空间变异受土地利用方式、土壤类型和地形因子等因素共同影响,SOM高值区分布在西北部、西部和东部等石灰土分布的岩溶区和水田,低值区位于北部红水河沿岸的冲积土地带;（3）RK、GWRK、MM_OK和 MC_OK对SOM解释能力均较优,可用于岩溶区SOM预测制图。结合辅助变量因子的GWRK预测模型能有效消除空间变异因素的影响,克服岩溶区SOM含量的空间非平稳性,从而提高SOM含量模型的稳定性和精度,同时MC_OK模型能提高预测的准确度。   相似文献   

3.
广西阳朔思的村铅锌矿尾矿砂坝坍塌造成了大面积农田污染,已往报道多集中在金属矿山开采过程中产生的废液及大量固体废弃物堆砌而造成的环境污染,较少关注因尾矿砂坝坍塌所造成的这种土壤重金属特殊污染模式。本文运用典范对应分析(CCA)研究铅锌矿尾砂坝坍塌对不同土地利用类型(玉米地、柑橘园、水稻田)造成的重金属(铅、锌、铜、镉)污染以及对土壤理化性质(有机碳、碱解氮、速效磷、速效钾、阳离子交换量、碳氮比、pH值)的影响。CCA分析结果表明,研究区污染以铅、锌、镉为主,铜次之,其中锌和镉的空间分布格局受土地利用类型的影响更明显,并且镉对水稻田产生的环境风险最高。此外,在土壤中尾矿砂分布不均的前提下,土地利用类型是造成土壤重金属污染空间分布不同的重要驱动力,受土壤质地和矿砂性质的影响,重金属污染引起的酸化效应在供试土壤中不明显,使得CCA图中pH值所代表的点远离重金属箭头连线;阳离子交换量距重金属连线较近,受重金属影响明显并随重金属污染的加剧而减小;碱解氮、速效磷、速效钾等速效养分受重金属污染的影响并不显著,但与施肥配比和农业管理密切相关;有机碳与重金属箭头连线分布象限相同且包裹于其中,与重金属质量分数呈正相关关系,相较于玉米地和柑橘园,水稻田中有机碳积累量更大,达到18.14 g/kg,可能因稻田中微生物的碳源代谢利用能力明显降低,土壤中有机碳的矿化分解受阻,导致水稻土中有机碳的积累。此外,尾矿砂作为土壤重金属的持续性释放源,尽管对土壤的基本理化性质尤其是速效养分的影响并不明显,但能够通过影响土壤微生物群落间接影响土壤碳循环。  相似文献   

4.
In the present study we examined the Ba, Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn contamination levels of the soils of Berehove, a small city in West-Ukraine. As a first step we determined the spatial distribution of the heavy metal contents of the urban soils; then, by studying the land use structure of the city and by statistical analysis we identified the major sources of contamination; we established a matrix of correlations between the heavy metal contents of the soils and the different types of land use; and finally, we drew a conclusion regarding the possible origin(s) of these heavy metals. By means of multivariate statistical analysis we established that of the investigated metals, Ba, Cd, Cu, Pb and Zn accumulated in the city’s soils primarily as a result of anthropogenic activity. In the most polluted urban areas (i.e. in the industrial zones and along the roads and highways with heavy traffic), in the case of several metals (Ba, Cd, Cu, Pb, Zn) we measured concentration levels even two or three times higher than the threshold limit values. Furthermore, Cr, Fe and Ni are primarily of lithogenic origin; therefore, the soil concentrations of these heavy metals depend mainly on the chemical composition of the soil-forming rocks.  相似文献   

5.
This study proposes the method of simulating spatial patterns and quantifying the uncertainty in multivariate distribution of heavy metals (Cr, Cu, Ni, and Zn) by sequential indicator simulation (SIS) combined with conditional Latin hypercube sampling (cLHS) in Changhua County, Taiwan. The cLHS is used for a sampling then for SIS mapping and assessing uncertainties of heavy metal concentrations. The indicator variogram results indicate that the 700 cLHS samples replicate statistical multivariate distribution and spatial structure of the 1,082 samples. Moreover, the SIS realizations based on 700 cLHS samples are more conservative and reliable than those based on 1,082 samples for delineating soil contamination by all heavy metals with the exception of Zn. Given adequate sampling, soil contamination simulation provides sufficient information for delineating contaminated areas and planning environmental management.  相似文献   

6.
长期地下煤炭开采在地表产生了大面积的塌陷塘,并造成了不同程度的水域污染。为研究塌陷塘重金属的分布特征及成因,选择了8种对环境影响较大的重金属元素（Fe,Mn,Zn,Cu,Cr,Cd,Pb,Ni）为研究对象,以淮南潘集一矿塌陷塘为研究区域,利用ArcGIS地统计模块中的协同克里格算法,通过水体实测光谱反射率作为协变量来估算水体中的重金属含量空间分布特征。结果表明:水体实测光谱与重金属含量有较好的关系,以水体光谱为协变量的协同克里格插值与单变量的普通克里格插值相比,8种重金属元素的预测值与实际值之间的均方根误差明显减少,证明水体实测光谱适合作为协变量来估计水体重金属的空间分布情况。综合分析发现,水体中的Cd,Pb,Cu,Ni主要来自水域西北部的煤矸石堆山,且Cd,Cu,Pb含量均超过了当地的背景值,对环境影响较大;Cr主要来自农业肥料、成土母质和周边道路旁的煤泥灰厂及煤矸石堆;Zn的来源主要是煤矸石、上游生活污水、农业肥料、土壤母质,由于其含量较低,对水环境质量的影响不大。   相似文献   

7.
近年来农用地土壤质量受重金属污染影响进而导致农产品受到威胁的问题愈发严重,然而关于土壤质量评价的研究很少考虑土壤污染状况,忽略了土壤污染风险对土壤质量的影响。本文以某典型制造业县级市为例,在以土壤理化性质为主要指标的土壤肥力状况评价基础上,对研究区土壤重金属进行污染风险管控类型划分。通过建立分段函数将土壤污染风险管控类型划分结果引入土壤质量评价体系,对农用地土壤质量进行评价。结果表明：研究区土壤理化指标的变异系数从大到小为速效磷(AP)含量>土壤电导率(SEC)>全磷(TP)含量>土壤有机碳(SOC)含量>阳离子交换量(CEC)>全氮(TN)含量>pH。土壤肥力状况随地势降低和河流增加呈现升高的趋势,高肥力区主要分布在平原区西北部和平原区东北部,低肥力区主要分布在东南部丘陵山区和西部低洼区,肥力过渡区环绕低肥力区分布。农用地土壤污染风险管控类型的划分结果表明,Cd、Hg、As、Pb、Cr、Ni、Cu和Zn 8种重金属中至少有88.89%的Cd样点和98.61%的Cr样点属于优先保护类,11.11%的Cd样点、1.39%的Cr样点属于安全利用类,该区重金属污染以Cd为主。土壤质量评价结果表明,土壤质量总体分布与土壤肥力状况分布规律类似,但由于受土壤污染风险的影响,研究区西南部低质量土壤范围向东扩张,东南部低质量土壤分布范围更小,更密集化。上述研究结果说明,引入土壤污染风险管控类型划分结果一般会对土壤肥力状况作减幅修正,并在一定程度上改变原土壤肥力状况的空间分布格局。  相似文献   

8.
邬光海  王晨昇  陈鸿汉 《中国地质》2020,47(6):1838-1852
为研究内蒙古赤峰市废弃钨钼矿区周围土壤重金属污染特征、潜在生态风险及成因分析，共采集83份表层土壤样品和6个土壤钻孔。采用ArcGIS空间插值分析方法研究As、Cd、Cr、Cu、Ni、Pb、Mo和Zn的空间分布，构建重金属扰动指数函数研究重金属受人类活动的污染程度，利用地累积指数法验证矿区周围土壤重金属污染程度，通过相关性分析判断重金属来源并讨论污染成因。结果表明：矿区周围土壤As、Cd、Cu、Pb、Zn和Mo平均含量明显高于矿区周边背景值，高含量主要分布尾矿库周围，主要来源为矿山采选活动；Cr和Ni基本无污染，主要来源为母岩风化。通过重金属扰动指数函数计算发现：采用区域背景值对矿区周围进行重金属污染评价夸大了矿山采选活动对矿区周围土壤重金属的污染，矿区周围土壤重金属污染是由于天然重金属富集和采矿活动共同作用下的“双驱动模式”导致，尾矿库周围土壤重金属污染程度随着与尾矿库水平距离的增加和深度的加大而逐渐降低。降水量丰富程度是影响重金属迁移能力的关键因素，该矿处于降水量匮乏地区，尾矿库对周围土壤重金属污染范围有限，对生态环境影响轻微。  相似文献   

9.
GIS支持下的农业土地资源评价研究—以贵阳市区为例   总被引：9，自引：0，他引：9  
本文基于土地质量评价的“压力－状态－响应”（PSR）模型，选取土壤重金属污染作为评价的一个压力为指标，应用GIS对贵阳市区农业土地资源进行了综合质量评价。定量评价的结果表明，区域农业土地资源中大部分土地资源重较好，但旱地和水田共有17．11km^2的重金属重度污染区，这部分耕地已不适宜种植农作物，同时，适合人类耕作的高质量耕地由于土壤重金属污染减少了近1／3，说明贵阳市区进行土壤重金属污染防治具有重要的意义。  相似文献   

10.
文中以铜陵地区As、Cd、Cu、Pb、Tl、Zn等6种土壤污染元素为例,选取常用且具有代表性的反距离加权法、径向基函数法、普通克里格法、多维分形法4种空间插值方法,进行土壤元素空间插值,并对其结果进行验证分析和评价。各方法均选取最优参数进行插值对比,土壤样本数共372个,其中337个用于插值计算,35个不参与插值计算而用于验证插值结果。对比研究显示,普通克里格法对刻画区域土壤元素的空间分布趋势效果最佳,但其半变异函数模型及参数的优选仍有待进一步研究;多维分形法对刻画土壤元素局部异常和污染效果最佳,但其对土壤元素分布普遍特征的反映仍需深入研究;反距离加权法和径向基函数法对土壤元素分布的空间插值精度一般,但其简单易用、插值最优参数易于选择。  相似文献   

11.
为科学评价现有耕地质量水平,利用环境卫星、Landsat8遥感影像以及地球化学调查等数据,提取了土壤肥力、水分、重金属污染等多种指标信息,采用与土壤水含量相关性更强的TVDI代替传统的DVI方法,建立了基于压力-状态-响应模型（PSR）的土壤质量评价方法.运用层次分析法（AHP）为各评价指标赋予权重,结合专家评分与线性内插法实现评价因子的定量评价,最终将各评价因子进行空间权重叠加获得地块评价单元.评价结果表明：海伦市一级耕地占28.75%,二级耕地占71.17%,三级及以下耕地占0.08%,耕地质量总体较高.通过对不同等级耕地空间分布的结果分析,提出了针对性的耕地改良建议.  相似文献   

12.
廖启林  任静华  姜丽 《江苏地质》2018,42(4):651-661
通过对河流沉积物等地表沉积物中重金属元素分布等环境地球化学调查数据的统计分析,总结了江苏典型地区河流沉积物中重金属元素的分布特点与规律:江苏局部地区河流沉积物中,Cd、Pb、Zn、Cr、Cu、Ni、Hg等相对富集趋势明显,Cd最大富集倍数 100;不同河流沉积物的重金属元素分布存在差异,与其污染来源密切相关;工业排放是导致河流重金属污染的主要原因,使用含Cd的颜料作为调色剂导致部分河流出现严重Cd污染;与土壤等其他地表沉积物相比,河流沉积物中重金属元素的分布更不均衡。查明河流沉积物的重金属元素分布可为相关农产品安全性预测、确定重金属污染来源、追踪涉重产业的发展历程、防治局部耕地重金属污染等提供科学依据。  相似文献   

13.
利用1∶25万土地质量地球化学调查数据分析和研究了安徽省宣城市南部地区土壤中As、Cd、Cr、Cu、Hg、Ni、Pb、Zn 8种重金属元素的地球化学特征以及重金属异常来源。调查发现地质背景是土壤元素含量的主控因素,调查区表、深层土壤重金属元素含量空间分布特征与地质背景、沉积环境表现出显著的空间一致性,重金属高含量成土母岩(荷塘组、皮园村组、蓝田组等地层)是土壤重金属元素高异常的主要影响因素,此外矿山开采、大气干湿沉降也是土壤重金属高异常的影响因素之一,土壤中Pb、Hg、Cd、Cr元素具有大气干湿沉降的输入来源。调查区土壤重金属污染风险主要影响指标为Cd,土壤Cd超过农用地土壤污染风险管制值的样品比例为2.56%,形态分析结果显示土壤Cd以离子交换态为主,结合农作物调查发现在土壤Cd高异常区存在一定的生态风险。  相似文献   

14.
In the absence of documentary evidence about settlement form and agricultural practice in northwest Scotland before the mid‐18th century, a geoarchaeological approach to reconstructing medieval land use and settlement form is presented here. This study applies multielemental analysis to soils previously collected from a settlement site in the Hebrides and highlights the importance of a detailed knowledge of the local soil environment and the cultural context. Geostatistical methods were used to analyze the spatial variability and distribution of a range of soil properties typically associated with geoarchaeological investigations. Semivariograms were produced to determine the spatial dependence of soil properties, and ordinary kriging was undertaken to produce prediction maps of the spatial distribution of these soil properties and enable interpolation over nonsampled locations in an attempt to more fully elucidate former land‐use activity and settlement patterns. The importance of identifying the spatial covariance of elements and the need for several lines of physical and chemical evidence is highlighted. For many townships in the Hebrides, whose precise location and layout prior to extensive land reorganization in the late 18th–early 19th century is not recoverable through plans, multi‐elemental analysis of soils can offer a valuable prospective and diagnostic tool. © 2007 Wiley Periodicals, Inc.  相似文献   

15.
张家口北部坝上草原地区属于典型的半干旱草原牧区, 近年来受到人为活动影响, 土地荒漠化加剧, 草原生态系统受损严重。本研究依据张北县二台镇土地利用现状边界布设了136个土壤采样点, 测定了土壤21个指标。运用主成分分析法与GIS空间插值(IDW)方法来分析土壤中重金属元素的空间迁移富集与分异机理, 并采用地累积指数法、潜在生态危害指数法对表层土壤9种重金属元素(Cd、Hg、Mn、Cr、Cu、Pb、Zn、Ni和As)污染程度、生态风险进行评价。结果显示: 研究区9种重金属元素土壤环境质量单指标等级评价以一等、低风险土壤为主。根据因子分析和主成分分析, Hg、Pb受人类活动及成土母质控制, 其余7种元素均受成土母质的控制。地累积指数结果显示, 9种重金属元素除Hg以外地累积指数均小于0, 总体为无污染等级, Hg为中污染等级。潜在生态危害指数结果显示Hg和Cd为潜在危害元素, 其中Hg整体达到很强生态危害程度, Cd达到中等生态危害程度, 其他元素为轻微生态危害程度。重金属综合生态危害指数(RI)表明在研究区七间窑村—哈拉勿素村以西地区为中等生态危害风险区, 其余地区为轻微生态危害风险区。  相似文献   

16.
This paper assesses the agricultural land resources of Guiyang City by means of GIS,on the basis of the pressure-state-response model in which soil heavy metal contamination is selected as a pressure indicatror.he results suggest that most of the agricultural land resources are of good quality,However,there are 17.11km^2 dry land and paddy field,which belong to the region of serious heavy metal contamination and are not fit for planting crops.At the same time,the high quality plowland,which is suitable for cultivation,has decreased nearly by 1/3 due to soil heavy metal contamination.These findings may improve our understanding that it is very important to prevent and cure heavy metal contamination of Guiyang City.  相似文献   

17.
Soil contamination by heavy metals has been a major concern for last few decades due to increase in urbanization and industrialization. The main objective of this research was to identify the heavy metal contaminated zones in the study area. Twenty five soil samples collected throughout the agriculture, residential and industrial areas were analysed by X-ray Fluorescence Spectrometer (XRF) for trace metals and major oxides. These metals can affect the quality of soil and infiltrate through the soil, thereby causing groundwater pollution. Based on the chemical analysis of major oxides (SiO2, Al2O3, ?Fe2O3, MnO, MgO, CaO, Na2O, K2O, TiO2, and P2O5) and their distribution; it is observed that these soils are predominantly siliceous type with slight enrichment of alumina component in the study area. Correlation matrix (CM) and factor analysis (FA) is employed to the heavy metal variables, viz., Ba, Cr, Cu, Ni, Pb, Rb, Sr, V, Y, Zn and Zr of the soil to determine the dominant factors contributing to the soil contamination in the area. In the analysis, five factors emerged as significant contributors to the soil quality. The total contribution of these five factors is about 90%. The contribution of the first factor is about 45% and has significant positive loadings of Co, Cr, Cu, Ni and Zn. The contribution of second factor is 22% and has significant positive loadings of Rb, Sr and Y. The contribution of third, fourth and fifth factors is 10, 8 and 5% and show positive loadings for lead, molybdenum and barium respectively to the soil contamination. The spatial variation maps deciphering different zones of heavy metal concentration in the soil were generated in a GIS (geographic information system) based environment using ArcGIS 9.3.1. The results reveal that heavy metal contamination in the area is mainly due to anthropogenic activities.  相似文献   

18.
Cement’s dust particles contamination on soil has received a good amount of attention due to toxicity persistence in the environment. It must be noted that cement dust falls are enriched in toxic heavy metals, which can spread throughout a large area by wind and rain then accumulate on plants, animals, and soils, thus ultimately affecting human health. For this purpose, a study was achieved to evaluate the potential accumulation and spatial distribution of heavy metals in topsoils surrounding the Meftah cement factory, situated at the southeastern of Algiers region. Sixty six soil samples were collected following six directions (east, northeast, north, northwest, west, and southwest) from cement factory on a radius of 3.5 km approximately. The physicochemical parameters, such as the pH, the conductivity, and the organic matter of these samples were determined. The concentration of the Cd, Cu, Pb, and Zn elements, in soil samples, were determined with flame atomic absorption spectrophotometry (FAAS) method and the data generated were analyzed statistically. Thus, the enrichment factor (EF), pollution index (PI), contamination factor (CF), pollution load index (PLI), geoaccumulation index (Igeo), and principal component analysis (PCA) was performed to the dataset in order to calculate and estimate the enrichment of metal concentrations in soils. Moreover, mapping of the spatial distribution of heavy metals was carried out using geographic information system (GIS), to determine more polluted areas and accomplish the objectives of the study. The results of our analysis indicate that soils were polluted most significantly by metals such as lead, zinc, copper, and cadmium. It is thus important to keep systematic and continuous monitoring of the bag filter to reduce the cement dust emission. As possible, remediation activities be carried out on the soil of heavy metals and their derivatives to manage and suppress such pollution.  相似文献   

19.
It is challenging to perform spatial geochemical modelling due to the spatial heterogeneity features of geochemical variables. Meanwhile, high quality geochemical maps are needed for better environmental management. Soil organic C (SOC) distribution maps are required for improvements in soil management and for the estimation of C stocks at regional scales. This study investigates the use of a geographically weighted regression (GWR) method for the spatial modelling of SOC in Ireland. A total of 1310 samples of SOC data were extracted from the National Soil Database of Ireland. Environmental factors of rainfall, land cover and soil type were investigated and included as the independent variables to establish the GWR model. The GWR provided comparable and reasonable results with the other chosen methods of ordinary kriging (OK), inverse distance weighted (IDW) and multiple linear regression (MLR). The SOC map produced using the GWR model showed clear spatial patterns influenced by environmental factors and the smoothing effect of spatial interpolation was reduced. This study has demonstrated that GWR provides a promising method for spatial geochemical modelling of SOC and potentially other geochemical parameters.  相似文献   

20.
This study was conducted to evaluate crops cultivated in reclaimed soils from subsidence areas that had been reclaimed in the Liuxin mining area, Xuzhou, China, to determine if such crops were safe. To accomplish this, heavy metals such as Hg, Pb, Cu, Cd, Cr, Zn and As (metalloid) concentrations in different parts of wheat planted in the research area were detected. The single contamination index method and comprehensive contamination index method were used to estimate the level of heavy metal pollution in rhizosphere soil. Besides, the distribution of heavy metal concentrations in different organs of wheat of the research area was compared, and the enrichment coefficients of Cd and Cr, which as the primary pollutants, in different parts of wheat were determined and used to yield curve estimation, after which a Cd regression equation was constructed. Finally, a kind of visible expression method of heavy metal pollution in wheat was explored. The results showed that the rhizosphere soil of the research area reached the local standard, but as different organs of wheat differed in the ability of enrichment of heavy metals, the Cd and Cr concentrations in wheat grains exceeded the national food hygiene standard. The distribution and migration tendencies of Cd and Cr concentrations in different organs of mature wheat were consistent in reclaimed sites, but differed in control site. The Cd regression equation passed the model verification. The results of risk evaluation of Cd and Cr in the wheat grain revealed that the single contamination index of the three sites reached light to severe level, and the comprehensive contamination index ranged from light to medium pollution level. This research is of important practical value for monitoring the safety of plant grown in mining areas.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号