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1.
长白山自然保护区道路影响域土壤Zn和Pb分布及污染分析   总被引:2,自引:0,他引:2  
分别在长白山自然保护区北坡的阔叶红松林、针叶林和岳桦林等3种森林中不同利用强度的6个路段,垂直于道路设置长50 m、宽10 m采样断面,在距路基4、12、20、28、40和48 m随机采集表层0~20 cm土壤,利用ICP-ES测定土壤样品中Zn和Pb的含量。研究不同森林类型、不同利用强度道路50 m路域范围土壤重金属含量、分布特征和污染状况。结果表明:随道路利用强度增强,在阔叶红松林和岳桦林带,路域50 m范围土壤Zn和Pb含量增加明显;在针叶林带,路域50 m范围土壤Pb含量增加明显;随道路利用强度增强,Pb在阔叶红松林带路域土壤中积累范围为12~28 m,在针叶林带路域中积累范围为20~40 m,在岳桦林带路域0~50 m范围积累都明显;与阔叶红松林带土壤相比,岳桦林带路域土壤Pb含量变化对道路产生的Pb污染更敏感;利用强度强的岳桦林带路域土壤Zn和Pb的污染分指数最大,分别为1.49和1.52,都为轻度污染。  相似文献   

2.
巴基斯坦白沙瓦市铅和镉在不同路旁土壤及植物中的污染   总被引:1,自引:0,他引:1  
S. KHAN  M. A. KHAN  S. REHMAN 《土壤圈》2011,21(3):351-357
Soil and plant samples were collected from roadside sites (along with primary, secondary and tertiary roads) and reference site to investigate the contamination of soils and old common plant species with lead (Pb) and cadmium (Cd) in Peshawar City, Pakistan. All the data were analyzed using ANOVA analysis that showed a significant (P ≤ 0.01) variation in Pb and Cd concentrations in the roadside soils and plants as compared to the reference site. The mean concentrations of Pb and Cd were 53.9 and 6.0 mg kg-1 in soils and 49.1 and 10.9 mg kg-1 in plants, respectively. Significant variation (P ≤ 0.01) in concentrations of Pb and Cd in soil and plant samples along with primary, secondary and tertiary roads might be due to different traffic densities. The highest value (9.4) of metal accumulation index (MAI) was observed for Eucalyptus camaldulensis. In selected plant species, the Pb and Cd accumulation was found in the order of E. camaldulensis > Ficus elastica > Dalbergia sissoo > Alstonia scholaris. The roadside soils and plants were highly contaminated with Pb and Cd as compared to the reference site.  相似文献   

3.
磁性土壤中Cu和Zn污染的指示作用   总被引:1,自引:0,他引:1  
Concentrations of copper (Cu) and zinc (Zn) and various magnetic parameters in contaminated urban roadside soils were investigated using chemical analysis and magnetic measurements. The results revealed highly elevated Cu and Zn concentrations as well as magnetic susceptibility in the roadside soils. The mean concentrations of Cu and Zn in these roadside soils were almost twice those in average Chinese soils, with the mean magnetic susceptibility of the roadside soils reaching about 179 ×10^-8 m^3 kg^-1. This enhanced magnetic susceptibility was attributed to the presence of anthropogenic soft ferrimagnetic particles. A low frequency-dependent susceptibility (2.5%± 1.0%) observed in the roadside soils indicated the coarse multidomain (MD) ferrimagnetic grains to be the dominant contributor to magnetic susceptibility. The Cu and Zn concentration of the soils had highly significant linear correlations with magnetic susceptibility (P 〈 0.01), anhysteretic remanent magnetization (P 〈 0.01), and saturation isothermal remanent magnetization (P 〈 0.01). This suggested that heavy metals were associated with ferrimagnetic particles in soils, which were attributed to input of traffic emissions and industrial activities. Scanning electron microscopy and energy dispersive X-ray spectra of magnetic extracts of the roadside soils further suggested the llnk between the magnetic signal and concentrations of heavy metals. Thus, the magnetic parameters could provide a proxy measure for the level of heavy metal contamination and could be a potential tool for the detection and mapping of contaminated soils.  相似文献   

4.
Twenty five soil samples located nearby highways and streets of Caracas, Venezuela were collected and chemical, physical and mineralogical analysis were done to characterize them. The soils have light textures, neutral or slightly alkaline pH, medium to high organic matter content, and all of them have carbonate. Kaolinite and mica were the dominant clay minerals in all soil samples. Lead and Zn were extracted with 1N-3 to investigate the levels of these polluting heavy metals in these roadside soils. A very high level of Pb was found in the soils (average enrichment factor of 151.4), while Zn levels were much lower (average enrichment factor of 5.25), but still higher than normal soils' levels. These results are indication of strong metal pollution (especially by Pb) of Caracas' roadside soils, due to heavy transit of motor vehicles as well as to the exclusive use of highly leaded gasoline in Venezuela. Nevertheless both metals accumulate only on the surface layers of those soils located within 5 m from the roadside. These facts were taken as evidence of the low vertical and horizontal mobility of the metals, which was mainly attributed to the high pH of the studied soils (between 7.5 and 7.8). Three surface soil samples having high Pb and Zn levels were selected for chemical fractionation by McLaren and Crawford's (1973) methodology. It was found that less than 1% Pb and below 5.5% Zn were in exchangeable form in these soils. Therefore, Pb and Zn are predominantly present in non-exchangeable forms in the studied soils. These non-exchangeable metals tend to become associated with different soils materials. Lead is mainly associated with the organic fraction, as well as to the inorganic and residual fractions, and Zn is mainly associated to the inorganic and residual fractions, and also the iron oxides, being practically absent in the organic fraction.  相似文献   

5.
Abstract

The uptake of Pb by young, greenhouse grown corn plants from roadside soil samples was found to be not only dependent upon the total amount of Pb in the soil, but also upon the amount of Pb in the soil relative to the soils capacity to sorb Pb. This is in agreement with the uptake of Pb by corn grown on soils amended with PbCl2, although plant accumulation of Pb from roadside soils was much less than from PbCl2 amended soils at comparable Pb concentrations. The use of crushed limestone as a road building material which results in high soil pH values next to the roadside is probably responsible for the reduced plant availability of Pb in the roadside soils.  相似文献   

6.
Literature data on the historical reconstructions of the atmospheric lead deposition in Europe and the isotopic composition of the ores that are potential sources of the anthropogenic lead in the atmospheric deposition in the lower Volga steppes during different time periods have been compiled. The effect of the increasing anthropogenic lead deposition recorded since the Bronze Age on the level of soil contamination has been investigated. For the first time paleosol buried under a burial mound of the Bronze Age has been used as a reference point to assess of the current contamination level. The contents and isotopic compositions of the mobile and total lead have been determined in submound paleosols of different ages and their recent remote and roadside analogues. An increase in the content and fraction of the mobile lead and a shift of its isotopic composition toward less radiogenic values (typical for lead from the recent anthropogenic sources) has been revealed when going from a Bronze-Age paleosol to a recent soil. In the Bronze-Age soil, the isotopic composition of the mobile lead is inherited from the parent rock to a greater extent than in the modern soils, where the lead is enriched with the less radiogenic component. The effect of the anthropogenic component is traced in the analysis of the mobile lead, but it is barely visible for the total lead. An exception is provided by the recent roadside soils characterized by increased contents and the significantly less radiogenic isotopic composition of the mobile and total lead.  相似文献   

7.
上海城市中心区不同类型绿地土壤重金属污染特征   总被引:2,自引:1,他引:1  
滕吉艳 《土壤通报》2021,52(4):927-933
对上海城市中心城区公园绿地土壤和道路绿地土壤中Pb、Cu、Zn、Cr、Cd和Ni的污染特征进行了研究,发现除Cr和Ni外,土壤中重金属均出现富集现象,且公园绿地土壤中重金属含量普遍低于道路绿地土壤;土壤重金属污染潜在生态风险评价结果表明6种重金属中,Cd污染最严重,其潜在生态危害系数最高,总体上公园绿地土壤重金属污染潜在生态风险处于中等水平,而道路绿地土壤重金属污染则处于较高水平,且均受Cd污染控制;多元统计分析结果表明,中心城区绿地土壤中重金属主要源于交通排放和工业活动释放,道路绿地土壤重金属更易受交通排放污染的影响。  相似文献   

8.
The emission of Platinum–group elements (PGE) from automobile catalytic converters has led to rapid increases in Pt, Pd and Rh concentrations in roadside media. This paper examines the temporal variability of PGE levels in road dusts and roadside soils on a seasonal basis over a 12 month period. Road dust and roadside soil samples were analysed by ICP–MS following microwave digestion and cation exchange. Concentrations of PGE in all road dust and roadside soil samples are elevated above local background concentrations with maximum levels of Pt?440 ng g?1, Rh?91 ng g?1 and Pd?440 ng g?1. Systematic seasonal variations in PGE levels are observed in both sample types and the temporal distribution of PGE levels is affected by a number of factors including surface morphology and rainfall. PGE ratios in road dusts and soils are consistent with known catalytic converter composition throughout the sampling period indicating the PGE remain associated during mobilisation and transport.  相似文献   

9.
A multi-media monitoring field investigation, which included atmospheric, road sediment and soil samples, was carried out at two highway study sites to identify past and present Pb sources. Past Pb anthropogenic sources such as paint and leaded gasoline were linked to significant Pb accumulation in roadside soils at both sites through Pb isotopic analyses. This was achieved by identifying the distinct Pb isotopic composition in older versus newer Pb accumulation at different depths across the soil profile. Older Pb accumulations exhibited lower 206Pb/207Pb isotopic ratios, consistent with Canadian Pb-bearing ores, whereas newer Pb accumulations reflected a mixture of the 206Pb/207Pb ratios of road sediment samples, with the Pb isotopic signature of uncontaminated soil. Isotopic analyses were also helpful in identifying road sediment as an important current source of Pb in roadside soils, by comparing the isotopic signatures derived from road sediment and atmospheric dustfall. The known association of Pb with anthropogenic sources was used to indirectly relate other metals (Cu, Mn, Zn) to the same source by the Enrichment Ratio method. Significant positive correlations at the 90–95% confidence level were found between Cu, Zn and Pb Enrichment Ratios in roadside and dust deposition samples. Weaker correlations were found between Mn and Pb, at the highway study site with the least amount of traffic. However, correlations between these two metals were significant at the 90% confidence level for the busier highway site highlighting Mn potential anthropogenic source. An isotopic tracer study is suggested to further investigate the process of Mn redistribution in the environment due to exhaust fuel emissions. More research is needed regarding the potential impact from using a Mn-based fuel additive.  相似文献   

10.
公路旁土壤中水分和重金属的迁移   总被引:14,自引:0,他引:14  
Roads with very high traffic loads in regions where soils are low in both pH and sorption capacity might be a source of percolation water loaded with heavy metals. Looking at some "worst case" scenarios, this study focused on the input of traffic related pollutants and on Pb, Cd, Cu, Zn, Ni and Cr concentrations in the soil matrix and soil solution, respectively. The analysis also included pH and electrical conductivity and at some sites DOC. The investigations were carried out on sandy soils with more or less low pH values at four motorway sites in Germany. The average of daily traffic was about 50 000 up to 90 000 vehicles. Soil pore water was collected in two soil depths and at four distances from the road. The pH in general decreased with increasing distance from the roadside. The elevated pH near the roadside was presumably caused by deposition of dust and weathering residues of the road asphalt, as well as by infiltration of salt that was used during winter time. At these road sites, increased heavy metal concentrations in the soil matrix as well as in the soil solution were found. However, the concentrations seldom exceeded reference values of the German Soil Protection Act. The soil solution concentrations tended to increase from the road edge to 10 m distance, whereas the concentration in the soil matrix decreased. Elevated DOC concentrations corresponded with elevated Cu concentrations but did not substantially change this tendency. High soil water percolation rates were found near the roads. Thus, even low metal concentrations of percolation water could yield high metal loads in a narrow area beside the road.  相似文献   

11.
The mobility of fluorescein and bromide used as tracers in packed soil columns was investigated. Five different soils were used in two application methods: soil surface application and soil incorporation, both of which simulate accepted methods of soil application of termiticides to prevent structural infestation. The breakthrough of bromide and fluorescein in column eluates were measured. The absorbance of fluorescein at 492 nm was pH dependent, and proper adjustments were made after measuring the eluate pH. Although high recoveries of bromide from the soil columns were observed, the breakthrough was different among the soil types, indicating that bromide behaves differently in different soils. Recovery of fluorescein, a weak acid, varied depending upon the pH of the soil used, and was only observed in the eluates of two of the five soils tested. Soil treated with bromide and fluorescein followed by soaking extraction showed high recovery of bromide but low recovery of fluorescein, except for in the most alkaline of the soils tested. If fluorescein is used as a conservative tracer in pesticide soil mobility studies, mobility can be underestimated in acidic soils because the active ingredient might travel more quickly than does the fluorescein.  相似文献   

12.
白世强  卢升高 《土壤通报》2007,38(3):544-548
对洛阳城市不同功能区表土中的Pb含量与化学形态以及工业和交通对土壤Pb污染的影响进行了研究,结果表明洛阳城市表土中Pb的含量分别为工业区(126.94mg kg-1)>城市道路(77.44mg kg-1)>居民区(59.76mg kg-1)>郊区农用地(52.39mg kg-1)>公园(41.43mg kg-1)>高校校园(36.49 mg kg-1)。工业区周围的土壤Pb含量随与工业区距离的增加而下降,应用地积累指数评价,洛阳城市土壤Pb污染处于轻度到中度污染之间,其中工业区和城区道路地积累指数较高,这些区域的土壤已受到Pb的较强污染。公路和铁路沿线两侧土壤中Pb含量分布也随距离的增加而下降,交通沿线两侧最大的Pb浓度在主导风向一侧10米附近。城市土壤Pb的化学形态以残余态和铁锰氧化物结合态为主,各形态比例为残余志>铁锰氧化物结合态>碳酸盐结合态>有机结合态。  相似文献   

13.
The fumigant 1,3-dichloropropene (1,3-D), in combination with chloropicrin, is considered a major replacement to methyl bromide (MeBr). This study was conducted to better understand phase partitioning of 1,3-D and the role of organic matter in its adsorption to soil. Partition of 1,3-D between air and water (K(H)), and between soil and water (K(f)), was determined by quantifying the concentration in both phases upon equilibrium. At 20 degrees C, the K(H) values of (Z)- and (E)-1,3-D were 0.052 and 0.033, respectively. In four California and Florida soils, the K(f) values of 1,3-D isomers ranged from 0.39 to 8.55, and the K(oc) values ranged from 18 to 60. The relatively high K(H) and low K(f) imply that 1,3-D is highly mobile in most soils after subsurface application. Adsorption of 1,3-D in native soils and soils amended with manure compost increased with increasing soil organic matter content. This suggests that organic wastes may be applied to soil to increase 1,3-D adsorption, thus reducing its potential for offsite movement.  相似文献   

14.
融雪剂在路域土壤中的累积、扩散及其对土壤性质的影响   总被引:4,自引:0,他引:4  
以我国吉林省多条常年使用融雪剂的高速公路为对象,研究了融雪剂成分在路域土壤中的累积、扩散及其对土壤相关理化性质的影响,结果表明;(1)道路使用氯盐型融雪剂后,路域土壤表层(0-20cm)的酸碱性、电导率及盐分离子的组成均有明显变化,总体呈电导率增加.Na~+、Cl~-的含量及比例上升的趋势,其中以道路隔离带土壤的变化量最为显著,并已表现出明显的盐化及钠质化趋势.(2)融雪剂对当地路域土壤的影响范围为距路基3m范围内,在此范围内土壤电导率及主要盐分离子Na~+、Cl~-的含量均显著高于对照土壤.各离子成分在土壤剖面的迁移、分布无明显规律性,其原因主要与土壤本身的理化特性及环境条件如降雨量等因素有关.(3)融雪剂成分在路域土壤中的大量蓄积改变了土壤的自然物质组成,其中Na~+、Cl~-的累积是影响土壤理化性质的主要因子,一方面其含量的增加可引发土壤的盐化、酸化、钠质化以及土壤结构的破坏.同时,Na~+浓度的提高也加大了其余养分离子置换流失的可能,成为影响植物正常生长、降低土壤肥力和增加环境风险的重要因素.  相似文献   

15.

Purpose

The overall objectives of this study were to examine the relationship between the concentrations of heavy metals such as Pb, Zn, Cu, and Cd in roadside soil derived from three different geological parent materials, Hawkesbury Sandstone, Wianamatta Shale, and Mittagong Formation and also to examine the influence of rainfall events on heavy metal concentrations in both the topsoil and the subsoil in all three soil types. In this paper, the focus is on lead and zinc.

Materials and methods

The results obtained from the samples taken from an initial transect were used to select the location of the study sites. Soil samples were collected using a stainless steel auger at distances of 1, 5, and 10 m from the edge of two major roads of similar traffic volumes bordering a suburban park. At each of five study sites, samples were collected at depths of 0–10 and 10–30 cm, three times pre-rainfall (after extended periods of no rain) and three times post-rainfall (after intensive rainfall periods). The modified aqua regia digestion method was applied for heavy metal concentrations measurement. To determine the temporal dynamics of trace elements in the soils, sequential extractions were applied to all the topsoil samples according to the modified three-step sequential extraction procedure.

Results and discussion

The corresponding concentrations of Pb and Zn were different for the soil derived from Hawkesbury Sandstone and Wianamatta Shale and also Mittagong Formation. The highest concentration of Pb was in the soil from Wianamatta Shale, 159.32 mg/kg and the highest concentration of Zn was in the soil from the Mittagong Formation, 254.12 mg/kg, all at a distance of 1 m from the roadside. From the sequential chemical extraction results, the rainfall substantially influenced the exchangeable fraction (F1) of Pb at a distance from the road of 1 m. A significant reduction of F1 was found for the soil derived from Mittagong Formation which also had the most significant reduction of total Zn concentration.

Conclusions

The interpretation of the results showed that there was a clear correlation between the concentration of Pb and Zn with the distance from the roadside and depth in all soil types. However, the results also showed that there are variable concentrations between the soil types. The heavy metal concentrations at the same distance for the three soil types are different. The rainfall events do influence the heavy metal concentration differently in both topsoil and subsoil of the three soil types at the same distance from the roadside.
  相似文献   

16.
Translocation and dispersion of chloride, bromide, nitrate and sulfate tracers in two typical Fluvi-Eutric Cambisols Chloride, bromide, nitrate and sulfate were applied as tracers on two weakly to moderately acidic Fluvi-Eutric Cambisols. The soil solution was sampled by ceramic suction cups down to a soil depth of 180 cm. At definite time intervals also soils material was taken from different depth to produce the soil saturation extract. The concentrations of the non-adsorbed anions chloride, bromide and nitrate were very similar in the suction cup solutions and in the saturation extracts, whereas the concentrations of the weakly adsorbed sulfate partially showed considerable differences. Obviously both methods extract in acid soils different fractions of the dissolved sulfate. By comparison of marked sulfate peaks with those of chloride, bromide or nitrate, which occur at the same time in different soil depth, a Kd value of 0.16 1/kg can be calculated for the Ap horizon and of 0.02 1/kg for the subsurface horizons of one Fluvi-Eutric Cambisol. Values of the dispersivity of the different horizons were estimated by varying the values of the dispersivity reported in the literature until the best fit of the simulated anion depth distribution to the measured values was found. The estimated dispersivities varied between 1.0 cm in the Ap horizon and 1.8 and 10.0 cm in the subsurface horizons.  相似文献   

17.
Preferential flow is the non-uniform movement of water and solutes through soils that bypasses a portion of the soil matrix. It limits the effective sorbing capacity of the soil and it has been related to a reduced solute residence time accounting for an increased risk of groundwater contamination. A dye tracer experiment and a subsequent soil sampling procedure in three adjacent soil profiles were performed in a moderately Pb contaminated roadside soil aiming to make visible different flow domains, to test whether preferential flow paths influence the metal content depth distribution, to study differences in selective soil properties resulting from flow domains and, lastly, to investigate whether preferential flow induces changes in the solid phase distribution of lead. Identified preferential flow domains showed greater lead concentration along with lower pH and greater amounts of both inorganic and organic C contents than unstained soil matrix domains. The ratio humic acids (HAs) to fulvic acids (FAs) contents was significantly lower in the preferential paths than in the matrix domains which might be related with sizable differences in the humification process. Lastly, based on the three-step BCR sequential extraction procedure, it has been shown that preferential flow phenomena induce differences in metal distribution between both identified flow domains. While lead content in the soluble and exchangeable (FI) as well as bound to organic matter fractions (FIII) were greater in the matrix than in the preferential flow domains, the amount of metal bound to Fe, Al and Mn (hydr)oxides (FII) was significantly greater in the preferential flow domain than in the matrix one. This indicates that more stable lead sorption mechanisms, thus leading to a lower metal mobility, might partially be responsible for the larger amount of total metal content found associated to the preferential flow paths. Overall, our results suggest that preferential flow domains may behave as metal storage compartments in the soils due to differences in soil properties promoted by means of the heterogeneous water flow distribution.  相似文献   

18.
Abstract. There is environmental concern about the increasing land application of dairy shed effluent in New Zealand. To minimize groundwater contamination by applied nutrients and pathogens it is desirable to avoid preferential flow through topsoils. Our objective was to determine an irrigation rate that retained applied effluent in the topsoil of two commonly irrigated New Zealand soils. In a field experiment, well drained Horotiu soils and poorly drained Te Kowhai soils were irrigated with a pyranine dye/KBr tracer solution at four rates (5, 10, 15, 20 mm/h) using a drip-type rainfall simulator. Twenty minutes after irrigation ceased the soil was excavated horizontally at 25 or 50 mm intervals, and photographed under UV light until no further fluorescence was vishle. Each layer was also analysed for bromide content, without subsampling. The wetting pattern was uneven in both soils as leachate moved preferentially through worm channels and structural cracks. Preferential flow was greatest in the Te Kowhai soil and increased at faster application rates. Dye fluorescence was curvilinearly related to bromide concentration. At both study sites, maintaining the irrigation rate at 10 mm/h minimized leachate movement into the subsoil. Pulsed irrigation at faster rates was not retained in the topsoil.  相似文献   

19.
Automobile traffic pollutes roadside environments with a range of contaminants. In this study, we investigate the distribution patterns of different contaminant classes in topsoils across a highway-forest interface north-east of Vienna, Austria, in order to assess spatial pollutant distribution and evaluate the filtering effect of roadside forests. We collected soil samples along transects perpendicular to the highway, and analyzed the soils for road salt residues (Na), total and mobile heavy metals (Pb, Cd, Cu, Zn, Ni, Cr) as well as polycyclic aromatic hydrocarbons (PAHs). Roadside soil pollution was highly heterogeneous. All contaminants followed an exponential-like decrease with distance from the road, reaching background levels at 5 to 10 m from the road curb. Traffic-born heavy metals in the immediate roadside zone tended to be more mobile than heavy metals of predominantly geogenic origin at greater distances from the road; the presence of road salt residues could have contributed to the elevated heavy metal mobility near the road. The forest vegetation acted as filter for PAHs shown by a sharp concentration increase at the forest edge. PAHs are likely transported with airborne soot particles that are scavenged by the wax-coated coniferous needles at our study site.  相似文献   

20.
Although lead (Pb) emissions have dropped drastically with the phase-out of tetra-ethyl lead (TEL) as a fuel additive, Pb deposited along highway corridors continues to be of concern because of its toxicity. This paper provides comprehensive data on the extent and distribution of Pb in roadside soils, Pb interaction with soils as a function of soil composition, the retention capacity of soil based on batch adsorption tests, the retention mechanism of Pb using selective sequential extraction, the potential for mobility using batch desorption tests with simulated rain and winter road salt, and column leach tests. Highway soils on high-traffic sections near Burnaby, Canada were found to have Pb accumulations up to 1628mg/kg soil. Contamination was mainly in the top 0.3m, with concentrations rapidly decreasing to the background level at a depth of 0.6m. The top layer contained more organic material and had a high adsorption capacity. Highway soils were found to have 3–10 times higher Pb adsorption capacities than the amount currently deposited. Selective sequential extraction indicated low exchangeable Pb in highway soils. Batch desorption tests with leaching solutions of H2O (pH 5.5), HNO3 solution (pH 4.0) and aqueous NaCl solution (0.17M) indicate low likelihood of significant leaching. Selective sequential extraction, leachate extraction and desorption tests show that Pb has limited mobility in highway soil.  相似文献   

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