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1.
The existence of a rainfall anomaly downwind of the St. Louis urban-industrial areas prompted a survey of area soils for elevated heavy metal concentrations. The goals of this work were to measure concentrations of Zn, Cd, and Ph, and to evaluate the role of the urban rainfall anomaly in their accumulation, in potentially-affected soils. Samples from three soil layers were collected from agricultural fields at 21 sites along two NE-SW transects. The samples were analyzed for pH, texture, cation exchange capacity, and total organic carbon, in addition to the three metals. The highest metal concentrations were observed near Granite City, Illinois, and coincided with an area of maximum Zn deposition in rain found in an earlier study. Only slight increases of the metals over background were found in the area of rainfall anomaly. Present rates of atmospheric deposition can account for these slightly elevated metal concentrations. However, the maximum concentrations found near Granite City cannot be accounted for by present atmospheric deposition rates. Other kinds of sources, or larger atmospheric deposition rates, perhaps during the operation of a local Zn smelter which closed about 1960, must have contributed. 相似文献
2.
Winfried Schröder Marcel Holy Roland Pesch Harry Harmens Ilia Ilyin Eiliv Steinnes Renate Alber Yuliya Aleksiayenak Oleg Blum Mahmut Coşkun Maria Dam Ludwig De Temmerman Marina Frolova Marina Frontasyeva Laura Gonzalez Miqueo Krystyna Grodzińska Zvonka Jeran Szymon Korzekwa Miodrag Krmar Eero Kubin Kestutis Kvietkus Sébastien Leblond Siiri Liiv Sigurður Magnússon Blanka Maňkovská Juha Piispanen Åke Rühling Jesus Santamaria Zdravko Spiric Ivan Suchara Lotti Thöni Viktor Urumov Lilyana Yurukova Harald G. Zechmeister 《Journal of Soils and Sediments》2010,10(8):1572-1584
Purpose
This study aimed at investigating correlations between heavy metal concentrations in mosses and modelled deposition values as well as other site-specific and regional characteristics to determine which factors primarily affect cadmium, lead and mercury concentrations in mosses. The resulting relationships could potentially be used to enhance the spatial resolution of heavy metal deposition maps across Europe.Materials and methods
Modelled heavy metal deposition data and data on the concentration of heavy metals in naturally growing mosses were integrated into a geographic information system and analysed by means of bivariate rank correlation analysis and multivariate decision trees. Modelled deposition data were validated annually with deposition measurements at up to 63 EMEP measurement stations within the European Monitoring and Evaluation Programme (EMEP), and mosses were collected at up to 7,000 sites at 5-year intervals between 1990 and 2005.Results and discussion
Moderate to high correlations were found between cadmium and lead concentrations in mosses and modelled atmospheric deposition of these metals: Spearman rank correlation coefficients were between 0.62 and 0.67, and 0.67 and 0.73 for cadmium and lead, respectively (p?<?0.001). Multivariate decision tree analyses showed that cadmium and lead concentrations in mosses were primarily determined by the atmospheric deposition of these metals, followed by emissions of the metals. Low to very low correlations were observed between mercury concentrations in mosses and modelled atmospheric deposition of mercury. According to the multivariate analyses, spatial variations of the mercury concentration in mosses was primarily associated with the sampled moss species and not with the modelled deposition, but regional differences in the atmospheric chemistry of mercury and corresponding interactions with the moss may also be involved.Conclusions
At least for cadmium and lead, concentrations in mosses are a valuable tool in determining and mapping the spatial variation in atmospheric deposition across Europe at a high spatial resolution. For mercury, more studies are needed to elucidate interactions of different chemical species with the moss. 相似文献3.
Industrial development has increased fast in China the last decades. This has led to a range of environmental problems. Deposition of heavy metals to forest ecosystems via the atmosphere is one potential problem. In this paper we report results from a pilot study where the heavy metal levels in forest soils at four different sites have been measured. Three of the sites are located relatively close to the large cities Chongqing, Guiyang and Guangzhou; one site is located in a remote, mountainous area in Guizhou province. Total metal contents as well as fractions according to Tessier's scheme were determined. With a few exceptions, the metal concentrations can be characterized as low; i.e. in most cases within the range of what has been reported as typical background values in the literature. High content of arsenic (up to 100 ppm) was found in the samples from the site outside Guangzhou, most likely due to naturally high arsenic levels in the soil. Metals bound to organic matter and to iron- and manganese oxides were the dominant fractions. No clear differences in metal levels were found between topsoil and subsoil samples, indicating that the atmospheric deposition of heavy metals has been low. 相似文献
4.
探索不同功能区空气降尘中重金属通量特征并对其进行污染评价,对于了解空气降尘输入对土壤中重金属累积影响具有重要意义。对重庆主城的居住区(JZ)、文教区(WJ)、商业区(SY)、郊区(JQ)、交通区(JT)和工业-居住混合区(GJ)逐月进行空气降尘通量和Cr、Ni、Cd、Pb含量的测定。结果表明,工业–居住混合区的空气降尘通量平均值最高,文教区的最低。6类功能区秋季的降尘量相对较低。Cd、Cr、Ni和Pb的平均降尘量在不同功能区分布存在差异。空气降尘中4种重金属元素的平均含量为:Cd 2.14 mg/kg、Cr 66.36 mg/kg、Ni 27.69 mg/kg、Pb 98.33 mg/kg。6类功能区降尘中Cd、Cr、Ni和Pb 4种重金属含量一般冬季较高。地积累指数法的分析表明降尘中Cd污染最严重。经推算,以空气降尘的方式向土壤中输入的重金属,使重庆主城区土壤中Cd、Cr、Ni和Pb等4种重金属元素的浓度在累积100a后仍将低于《土壤环境质量标准》中的二级标准。土壤中重金属元素增加速度最快为Cd,其次为Pb和Cr,Ni的增长为负值。 相似文献
5.
农作物叶片对大气沉降重金属的吸收转运和积累机制 总被引：2，自引：0，他引：2
近年来,农产品的重金属超标问题已经引起了公众的广泛关注,也是国内外学者研究的热点。要实现农产品重金属污染的有效防控,首先需要解决的就是重金属来源问题。目前已有的研究大多集中在根系对土壤中重金属的吸收机制研究,且已基本探明作物根系对重金属的吸收转运机制,包括根际离子的活化,根细胞的吸附和扩散、跨膜运输,根皮层细胞的横向运输,中柱的薄壁细胞到木质部导管的装载,木质部向地上部的转运等一系列过程。但大气沉降对农产品重金属积累的贡献及叶片的吸收、转运和积累机制尚不清楚。若能深入研究农作物叶片对重金属的吸收、转运和存储机制,从分子层面解析其关键作用过程,则可从叶面吸收的角度实现农产品重金属积累的有效阻控,为保证农产品安全提供新的思路。本研究依据已发表文献,归纳并对比了叶片和根系对重金属的吸收、转运、区隔、积累过程及其主要机制,对比两种吸收途径下重金属的迁移、转运系数及对农产品可食部位的贡献率。发现植物可通过根系和叶片两种途径吸收重金属,已有研究中叶片吸收的重金属在作物体内可食部位的迁移和转运系数大大高于根系吸收的重金属,说明大气沉降是农产品重金属积累的重要来源。叶菜和茶叶类作物,由于其食用部位本身就是叶片,根系吸收和叶片直接吸收的大气沉降重金属都会积累在叶片中。因此,未来需要加强对大气沉降的监测,并采取措施控制大气污染,源头阻断是保证农产品安全十分必要的途径。同时还需进一步探明水稻等农作物叶片吸收转运重金属的过程和重要作用机制,以及可食部位累积重金属的关键生育期。并采用分子生物学等手段控制重金属转运蛋白的合成,以及叶片细胞膜的理化性状,降低吸附重金属的活性和转运能力,为寻求有效阻控叶片吸收重金属的措施提供理论和实践指导,保证农产品的安全生产。 相似文献
6.
Patricia E. Linton Laura Shotbolt Andrew D. Thomas 《Water, air, and soil pollution》2007,186(1-4):97-113
High concentrations of heavy metals are known to be toxic to many soil organisms. The effects of long-term exposure to lower levels of metals on the soil microbial community are, however, less well understood. The southern Pennines of the U.K. are characterised by expanses of ombrotrophic peat soils that have experienced deposition of high levels of heavy metals since the mid to late 1800s. Concentrations of metals in the peat remain high but the effect of the contamination on the in-situ microbial communities is unknown. Geochemical and molecular polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) and sequencing techniques were used to derive new information on the metal chemistry and microbial populations in peat soils from six locations in the southern Pennines. All sites were highly acidic (pH 3.00–3.14) with high concentrations of potentially toxic heavy metals, particularly porewater Zn and particulate-associated Pb. The results also reveal a split in site characteristics between the most polluted sites with the highest levels of bioavailable metals (Bleaklow, FeatherBed Moss and White Hill) and those with much lower bioavailable metals (Cowms Moor, Holme Moss and Round Hill). There was no difference in the number of dominant bacterial species between the sites but there were significant differences in the species composition. At the three sites with the highest levels of bioavailable metals, bacterial species with a high similarity to acidophilic sulphur- and iron-oxidizing bacteria and those from high metal environments were detected. The transformations carried out by these metal mobilising and acid producing bacteria may make heavy metals more bioavailable and therefore more toxic to higher organisms. Bacteria with similarity to those typically found in forest and grassland soils were documented at the three sites with the lowest levels of bioavailable metals. The data highlight the need for further studies to elucidate the species diversity and functionality of bacteria in heavy metal contaminated peats in order to assess implications for moorland restoration. 相似文献
7.
H.-S. Helmisaari J. Derome H. Fritze T. Nieminen K. Palmgren M. Salemaa I. Vanha-Majamaa 《Water, air, and soil pollution》1995,85(3):1727-1732
Distribution and fluxes of copper within Pinus sylvestris stands were studied during 1992–1994 along a heavy-metal pollution gradient in south-western Finland. The stands are situated at distances of 0.5, 4 and 8 km from a copper-nickel smelter that started operating in 1945 at Harjavalta. According to the results, copper concentrations in the soil, in the understorey vegetation and in the trees increased steeply towards the smelter. Almost 50 years' accumulation of heavy metals in the soil has caused direct toxic effects to soil microbes, thus decreasing decomposition and nutrient mineralisation. During the past few years, sulphur and heavy metal emissions from the copper and nickel smelter have been radically decreased. However, the heavy metals which have been accumulating in the soil for decades continue to affect the vegetation for a long time through soil processes. Consequently, long-term accumulation in the soil has to be taken into account when determining the critical loads of forest ecosystems for heavy metals. 相似文献
8.
Mosses, lichens and pine bark were compared as indicators of atmospheric heavy metal deposition in Finland. The samples were collected from the nationwide sampling network systematically covering the country as a whole. All three bioindicators showed a fairly similar result concerning heavy metal deposition. The major emission sources and the areas affected were reflected in the metal concentrations in the samples. However, there were differences between the accumulation of metals. The correlation between concentrations in mosses and lichens was generally higher than that between mosses and bark or lichens and bark. Concentrations in lichens were the highest and lichens reflected the regional differences in background areas as well as the local emission sources. The concentrations in the mosses were slightly lower than those in lichens and also the mosses pinpointed the emission sources and the extend of the areas polluted. Bark had the lowest concentrations and bark did not generally reveal regional differences as well as mosses and lichens. In spite of the differences, all three bioindicators proved to be suitable for monitoring atmospheric heavy metal deposition. 相似文献
9.
为探索铜冶炼厂周边农田区大气重金属沉降的时空变异特征,以冶炼厂为中心,四周等距离均匀分设8个监测点,于2012年5月至2013年4月,根据酸沉降检测技术规范,采收大气干湿沉降混合样品,利用原子吸收分光光度法分析样品中cu、cd、Pb、zn、cr含量,计算各监测点所代表区域各类重金属沉降通量。结果显示,研究区重金属cu、cd、Pb、zn、cr的年沉降通量分别为638、6．56、70．0、225、22．7mg·m^-1·a^-1。五种重金属沉降量具有一定的时间变化特征,其中cd、zn和cr的月际间变化显著（P〈O．05,n=96）,Pb、zn、cr季节间变化显著（P〈O．05,n=32）,而cu无显著的月间或季间变化。空间上,cu、cd、Pb年沉降通量有极显著性差异（P〈0．Ol,n=8）,以铜冶炼厂西南方向的九牛岗监测点最高,而zn和cr则无显著性差异。 相似文献
10.
大气沉降对土壤和作物中重金属富集的影响及其研究进展 总被引：12，自引：1，他引：12
以我国农田土壤-作物-大气系统为研究对象,综述了近年来大气沉降中重金属的来源及时空分布规律以及大气沉降对农田土壤和作物中重金属富集的影响及其研究进展。人为活动产生的重金属进入大气后,受多种自然和人为因素及环境保护政策等综合因素的影响,导致大气沉降中的重金属具有明显的时空分异特征:从时间分异来看,大气重金属含量呈现出冬季高于其他季节,供暖期高于非供暖期的特点;从空间分异来看,工业发达地区较高,燃煤为主的城市高于其他城市,城区高于郊区及远郊地区。大气沉降不仅会使土壤重金属含量上升,也会对农作物造成直接和间接的影响。大气中的重金属会通过气孔进入作物细胞,在细胞壁、液泡中积累,当含量过高时会影响作物正常生长或引起作物重金属超标风险,不利于农业安全生产。未来的研究应将传统分析方法与空间和地统计技术、多元同位素示踪技术、数学模型模拟等多种技术手段相结合,在区域尺度和田间自然条件下开展土壤-作物-大气系统重金属循环过程的研究,为区域农田重金属污染防控和环境管理提供科学依据和决策支撑。 相似文献
11.
The literature on the fluxes of six heavy metals in temperate forest ecosystems is reviewed. Special attention is given to wet and dry deposition and internal flux, to metal budgets for ecosystems and soils, to concentrations in aqueous compartments of the ecosystem and to speciation in soil solutions. Metal fluxes are discussed in relation to pollution load, soil type, tree species and land use. The mobility of Cu and Pb is strongly dependent on the solubility of organic matter. These metals are commonly accumulated in forest soils. Zinc, Cd and Ni are greatly influenced by soil acidity and are often lost in considerable amounts from acidified soils. Chromium is often at balance in forest ecosystems. Implications for metal solubility and budgets in forest soils are discussed in connection with an increase in soil acidification. 相似文献
12.
Andrew J. Friedland Arthur H. Johnson Thomas G. Siccama 《Water, air, and soil pollution》1984,21(1-4):161-170
The organic horizons of forest soils in eleven stands along an elevational gradient on Camels Hump Mountain, Vermont, were analyzed for Pb, Cu, Zn, Ni, Cd, organic matter and organic C. Lead concentration and amount increased with elevation. Vertical profiles of forest floor in the boreal forest showed that highest concentrations for most metals occurred in the upper F horizon. Comparison with 1966 and 1977 samples from the same stands showed that concentrations of Pb, Cu, and Zn and percent organic matter increased by as much as 148% in the intervening 14 yr. Estimates of 1966 amounts of Pb, Cu, and Zn indicated that increases in trace metal amounts over the 14 yr period are consistent with annual deposition rates reported in the literature. 相似文献
13.
Alpine areas in north-western Italy are subject to high deposition of atmospheric pollutants. Chemical investigations on high-altitude lakes indicate that most of them are recovering from acidification; however, they are still affected by the deposition of pollutants from the atmosphere, especially of heavy metals. This study compares the concentrations of heavy metals in alpine lake waters with those found in atmospheric depositions, to identify the possible contribution of deposition inputs to surface water ecosystems. The results were analysed by multivariate statistical techniques to identify the main emission sources of the various metals. Levels of trace metals in alpine lakes are generally low, and bedrock and surficial geology proved to be a major factor controlling metal concentrations in lake water. In fact, terrigenous elements show a wide range of concentrations while metals of anthropogenic origin, such as lead and cadmium, are often below the detection limits of the method; chrome and nickel are also present in very low concentrations. The median values of heavy metals in Italian alpine lakes are similar to those found in other lake surveys performed in remote areas, especially as regards metals of anthropogenic origin. The Visual MINTEQ model was applied to long-term chemical data of selected alpine lakes, to calculate aluminium speciation and to simulate its change in response to gradual modifications in a unit of pH. The ultimate aim of the modelling was to evaluate the possible threat to aquatic organisms of these highly toxic compounds.
相似文献14.
The value of several biological monitors of the distribution of airborne Cr and Ni dust was studied in the vicinity of ferrochrome and stainless steel works. The following indigenous biomonitors were compared: the forest mosses Pleurozium schreberi and Hylocomium splendens, the epiphytic lichen Hypogymnia physodes, bark of Scots pine (Pinus silvestris), needle litter, earthworms (Dendrobaena octaedra) and moths (mainly Xylena vetusta). Results were compared and related to the heavy metal deposition estimated by the vertical snow sampling method. The representative sampling size at different pollution levels was investigated. In Cr it varied from 1 to 300 mg m?2 a?1. Of the biomonitors studied, the mosses showed most effective accumulation of heavy metals, their results having a clear relationship to the deposition and good replicability. The lichen gave almost as good results as the mosses. Both mosses and lichens collected heavy metals more effectively at low to moderate pollution loads than near the pollution source. The accumulation of heavy metals in bark was lower than in the mosses or lichen. The heavy metal content of earthworms indicated the degree of pollution well, but the replicability of the method was poor. The accumulation of heavy metals in moths was low. 相似文献
15.
Irena M. Grze 《Pedobiologia》2009,53(1):65-73
Ants are considered to be relatively resistant to metal pollution, but the effect of metal toxicity on ant communities is poorly understood. This work examined the relationship between ant species diversity and heavy metal pollution at 16 meadow and forest sites along a metal contamination gradient in a mining and smelting region near Olkusz, Poland. Menhinick's index was used to estimate species richness. Pielou's index of evenness (J), Simpson's index of diversity (D) and the slopes of rank-abundance curves were used to estimate of species evenness. Regardless of species composition differences between forest and meadow, the increase in species diversity with increasing metal pollution was very clear in both ecosystems. The more polluted the site, the more species were detected and the more similar in relative abundance they were. Consequently, the extent to which one or a few species dominated a community decreased. This result can be explained by indirect effects of metal pollution, that is, changes in species interactions rather than by changes in abiotic conditions. 相似文献
16.
17.
新疆准东矿区土壤与降尘重金属空间分布及关联性分析 总被引：1，自引：3，他引：1
土壤重金属与大气降尘重金属之间的关联性可以反映重金属污染的来源、土壤-大气系统中重金属的传输、迁移和扩散特征。为了研究矿区表层土壤的污染状况及与降尘重金属质量分数间的关联性,该研究以新疆维吾尔自治区准东矿区为研究靶区,利用2014年采集的51个表层土壤和大气降尘样品的室内实测重金属质量分数数据,并基于此分析了样品中6种重金属(As、Cu、Cr、Hg、Pb、Zn)的空间分布特征、地积累指数以及潜在生态风险;利用Pearson相关性分析矩阵和灰色关联法对表层土壤与大气降尘中重金属浓度的相关性和关联度进行探讨。结果表明:1)准东矿区表层土壤重金属的分布状况存在着明显的空间差异,其中Hg的污染程度最严重,处于强-极强度污染,其潜在生态危害指数达到了较高生态风险;Zn和Cu基本处于无污染状态,属于轻微生态风险;2)大气降尘重金属空间分布存在着明显差异,降尘中的Zn处于极强度污染,Hg处于无污染状态;3)Pearson相关分析与灰色关联分析表明,准东地区表层土壤与大气降尘中6种重金属的相关系数大小顺序与关联度排序结果一致,其中Hg和As元素具有较强的一致性,且具有相同的来源,说明大气降尘对表层土壤中重金属的质量分数有一定影响。但因不同重金属元素沉降特性不同,导致各元素之间的关联度有所差异。 相似文献
18.
Soil pollution by elevated heavy metals exhibits adverse effects on soil microorganisms. Ammonia oxidizing bacteria and ammonia oxidizing archaea perform ammonia oxidative processes in acidic soils. However, influence of heavy metal stress on soil ammonia oxidizers distribution and diversity is inadequately addressed. This study investigated the responses of ammonia oxidizing bacteria and archaea to heavy metals, Cu and As during short-term laboratory experiment. Two different acidic alfisols named as Rayka and Hangzhou spiked with different concentrations of As, Cu and As + Cu were incubated for 10 weeks. Significant reduction in copy numbers of archaeal-16S rRNA, bacterial-16S rRNA and functional amoA genes was observed along elevated heavy metal concentrations. Ammonia oxidizing archaea was found to be more abundant than ammonia oxidizing bacteria in all the heavy metal treatments. The potential nitrification rate significantly decreased with increasing As and Cu concentrations in the two soils examined. Denaturing gradient gel electrophoresis analysis revealed no apparent community shift for ammonia oxidizing archaea even at higher concentrations of As and Cu. Phylogenetic analysis of archaeal amoA gene from 4 clone libraries indicated that all the archaeal amoA sequences were placed within 3 distinct clusters from soil and sediment group 1.1b of Thaumarchaeota. Our results could be useful for the better understanding of the ecological effects of heavy metals on the abundance and diversity of soil ammonia oxidizers. 相似文献
19.
Amanda L. Landre Shaun A. Watmough Peter J. Dillon 《Water, air, and soil pollution》2010,209(1-4):209-228
Atmospheric emissions of metals have decreased in North America; yet, metals remain an environmental concern due to their environmental persistence and toxicity to biota. In this study, pools and mass budgets were calculated for 15 metals in an acidified forested catchment in Central Ontario. Metals that were enriched in bulk deposition over background average values (As, Cd, Pb, Zn) were generally enriched in the forest floor and upper lake sediment. While the metal pool in vegetation is small compared with the soil pool, internal cycling of metals via litterfall is comparable to atmospheric deposition, soil water, and stream fluxes. Partitioning coefficients calculated from metal concentrations in soil water and bulk soil suggest that Cd, Mn, Ni, and Zn are the most mobile. The mineral soil and lake sediments were sinks for most metals, while the wetland was a source of metals during the study year, which was a drought year. Overall, lithogenic metals (Al, Ba, Co, Fe, Mn, Rb, Sr, Zn) primarily from a weathering source generally exhibited net export from the catchment, while metals contained in atmospheric pollution (As, Cd, Cr, Cu, Ni, Pb, V) exhibited net retention. Despite the acidified nature of the catchment, it functions to retain many pollutant metals. 相似文献
20.
A. Motelay-Massei D. Ollivon K. Tiphagne B. Garban 《Water, air, and soil pollution》2005,164(1-4):119-135
Concentrations of Cd, Cu, Ni, Pb and Zn were determined in bulk atmospheric deposition collected at five stations in the Seine River basin (France), to evaluate sources and fluxes of atmospheric trace metals. Bulk deposition (wet + dry) was sampled weekly from March 2001 to February 2002 for 4 sites and from March to December 2001 for the last one. The concentrations of the elements in bulk deposition (dissolved + particulate form) followed the order: Zn > Pb > Cu > Ni > Cd. Concentrations of Zn, Pb and Ni were highly correlated with one another, suggesting a common source, related to the combustion of coal and heavy fuel. Metal concentrations in bulk deposition did not exhibit a high degree of temporal variability over the annual cycle and were not obviously related to meteorological parameters (rainfall, wind). Estimates of the total annual direct atmospheric deposition of metals to the Seine Estuary ranged from 16 kg yr? 1 for Cd to 5600 kg yr? 1 for Zn. Loadings of Cd, Cu and Ni from direct atmospheric inputs were less than 1% of those contributed by the Seine River and loadings of Pb and Zn represented 1.27% and 1.56% of the Seine contribution. Direct atmospheric inputs are negligible compared to fluvial inputs, but the indirect atmospheric deposition to the estuary was not estimated. Based on these results, trace metal concentrations in Paris have decreased by a factor of 4.6 for Zn and by a factor of 50 for Ni from 1988 to 2001. Of particular interest is the continued decrease in bulk deposition of Pb during this period, underlining the impact of policy initiatives concerning the reduction of lead on emissions in France. 相似文献