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1.
不同城市功能区绿地土壤重金属分布及其生态风险评价   总被引:1,自引:0,他引:1  
对山东中部某典型城市9个城市功能区64个绿地土壤样品中的Cu,Zn,Pb,Cd 4种重金属元素含量进行了测定,评价了土壤重金属污染特征及其生态风险。结果表明:各功能区绿地表层土壤Cu,Zn,Pb和Cd的平均含量均高于当地自然植被土壤背景值,已表现出富集状态,其中Cd平均含量超标严重;工业区、风景名胜区、商业区和居民区等绿地土壤污染程度居前;单因子污染评价表明,该市绿地土壤中Cu,Zn和Pb已处于潜在污染状态,而Cd已经处于重污染状态;综合污染评价研究表明,处于“中度污染”污染级别的绿地类型有工业绿地、商业区绿地、风景名胜区和居住区绿地,而且苗木生产区和道路绿地也接近“中度污染”级别;潜在生态危害评价表明,该市绿地土壤处于轻微生态风险,但Cd潜在生态危害指数已经处于中等生态风险;土壤中Cu-Zn,Cu-Cd,Pb-Cd显著相关,Cu-Pb,Zn-Cd极显著相关,重金属之间存在一定复合污染现象,表明这些重金属元素的来源可能相同。该市绿地土壤Cd污染的防治应该引起重视。  相似文献   

2.
哈尔滨市城市土壤重金属生态风险评价   总被引:9,自引:0,他引:9  
孟昭虹  周嘉  郑元福 《水土保持研究》2009,16(2):152-155,159
研究哈尔滨城市土壤中Cd、Pb、Cr、Cu和Zn含量与分布特征,采用Hakanson潜在生态危害指数法对土壤重金属污染环境质量和潜在生态风险进行评价.结果表明:哈尔滨城市土壤5种重金属含量与松辽平原土壤背景值相比有较大积累,污染源的空间差异性引起不同功能区土壤重金属含量不同.土壤表层5种重金属污染程度:工业区>交通区>郊区耕地区>植物园区,潜在生态风险系数在工业区和交通区为中度危害,在郊区耕地区和植物园区为低度危害.最后,对土壤重金属污染来源进行综合分析,提出相应的管理防治对策.  相似文献   

3.
Distribution of lithogeneous, pedogeneous and anthropogeneous heavy metals in soils The study in hand shows relations between lithogeneously, pedogeneously and anthropogeneously enriched heavy metals and their concentration grades. Conclusions can be drawn from the vertical and horizontal distribution pattern of heavy metals on the nature and origin of their enrichment which is determined decisively by their mobility. Heavy metals enriched lithogeneously show relatively uniform as well as stratified concentration grades in the profile. A diminution of the heavy metal contents in all surface directions takes place starting from the centre of the lithogeneous enrichment. Pedogenetic processes lead to an increase of all element concentrations in certain soil horizons. Lateral transport causes an increase of heavy metal contents in the soils of low grounds compared with summits. Heavy metals enriched anthropogeneously are mostly accumulated in topsoils. Heavy metals concentrations due to dust immissions are characterized by a remarkable diminution of the concentration within the main wind direction. Heavy metal enrichments due to direct anthropogeneous charges are following the ground borders.  相似文献   

4.
Qualitative properties of soils in the urban area of Rostock different in use With the purpose of mapping urban soils in Rostock, Northern Germany. extensive investigations determining the presence, the genesis and the properties of natural and man-influenced soils were realized. In the following article selected chemical and physical properties of soils different in use situated on garden-, park-, graveyard-sites and living areas were shown and discussed. The positive influence on the pH-value in living areas of the city centre, deep enrichment of humus under garden use and the tendencies to soil acidification in sandy soils of park sites were emphasized.  相似文献   

5.
洛川苹果园地土壤重金属污染调查与评价   总被引:5,自引:1,他引:5  
郑国璋  岳乐平 《土壤通报》2008,39(2):402-405
通过对洛川苹果园地土壤样品的采集、监测,依据无公害果园产地土壤环境质量标准和绿色食品产地土壤环境质量标准,重点分析评价了对土壤环境及人体危害较大的Cd、As、Cr、Pb等重金属元素的污染现状。评价结果表明:以无公害果园产地土壤环境质量为评价标准,洛川苹果园地土壤重金属污染程度有As>Cr>Cd>Pb的特征,土壤重金属综合污染指数为0.51,土壤Cd、As、Cr、Pb单项污染指数平均值均小于0.7,土壤环境中的重金属元素含量现状水平符合无公害苹果生产的要求;以绿色食品产地土壤环境质量为评价标准,洛川苹果园地土壤重金属污染程度有As>Pb>Cr>Cd的特征,土壤重金属综合污染指数为0.64,土壤Cd、Cr、Pb单项污染指数平均值均小于0.7,土壤As单项污染指数平均值大于0.7,但小于1。土壤环境中的重金属含量现状水平符合绿色食品苹果生产的要求。但土壤As单项污染指数平均值为0.74,已超过绿色食品产地土壤污染警戒线。洛川苹果园地土壤重金属As污染程度较高,主要是由于人为长期不合理使用含As农药、化肥所致。因而,洛川苹果生产中应将土壤环境中的As作为严控的土壤污染物。  相似文献   

6.
杭州市城市土壤重金属的潜在可淋洗性研究   总被引:23,自引:0,他引:23  
章明奎  王美青 《土壤学报》2003,40(6):915-920
研究了杭州市城市土壤 8个重金属元素 (Cd、Co、Cr、Cu、Ni、Pb、Zn、Mn)的含量、形态和潜在可淋洗性。结果表明 ,该城市土壤中Cd、Cr、Cu、Ni、Pb、Zn和Mn均有明显的积累 ,其中Cd、Co、Cr和Ni主要以稳定的残余态为主 ,而Cu、Pb、Zn和Mn则以可提取态为主 ,因此在强还原、强酸性或有利于有机质分解条件下Cu、Pb、Zn、Mn的释放潜力较高。用荷兰能源研究中心的淋洗方法 (pH4 0 )测试表明 ,该市城市土壤的重金属可淋洗性较低 ,在一般条件下该城市土壤重金属不会有较大的释放 ,这与该城市土壤中酸可提取态重金属比例较低并含有较高的有机质及粘粒含量有关  相似文献   

7.
The use of earthworms in monitoring soil pollution by heavy metals Total heavy metal contents (HNO3-soluble) and exchangeable fractions (Ca(NO3)2-soluble) of Pb, Zn and Cd were measured in soils, litter layers and earthworms (dry masses) from forest, arable and pasture sites in a transect of the main wind direction and varying distances (1.5, 5.4, 11.4, 15.6 km) to a lead smelter near Bad Ems, Germany. Additionally, cast materials of Lumbricus terrestris-individuals were collected from the surface of the pasture sites. In the observed area total soil contents of Pb and Cd exceeded the C-level and total contents of Zn the B-level of the “Netherland-list”. Heavy metal contents in soils and earthworms decreased with increasing distance to the smelter. Pb showed the best correlation. Correlation between total contents of Pb and Cd in soils and earthworms were significant (rs = 0.66; p < 0.05 and rs = 0.67; p < 0.01, respectively). The uptake of heavy metals by Lumbricus rubellus, L. terrestris and Aporrectodea caliginosa was metal specific rather than species specific with factors of accumulation being <1 (Pb), 2.7–7.6 (Zn) and 19.5–85.5 (Cd). The heavy metal contents of the observed cast materials signified the different transfer of elements from soil material via earthworm individuals to the faeces. In the cast materials the amounts of Pb were high and the amounts of Zn and Cd were low. This indicates a high accumulation rate for Zn and especially for Cd in the tissues of the observed earthworm individuals. The present data support the necessity of ecotoxicological threshold levels.  相似文献   

8.
采用现场采样及室内分析方法,从水平和垂直角度研究了福州城市边缘区果园土壤Pb、Cu全量及其HCl、DTPA两种浸提态含量分布特征,利用潜在生态风险指数法评价土壤Pb、Cu潜在生态风险。结果表明,福州城市边缘区果园土壤Pb、Cu存在一定程度的污染,且Pb污染比Cu严重,不同浸提态Pb、Cu含量与其全量呈正相关,与pH呈负相关;Pb、Cu潜在生态风险处于轻微程度。  相似文献   

9.
为了解三江源代表性区域玉树县土壤重金属污染状况,评估土壤重金属潜在生态风险,以玉树县采集的121个土壤样本中的重金属含量数据为基础,采用地累积指数和潜在生态危害指数法对土壤重金属含量进行分析和潜在风险评价。结果表明:玉树县表层土壤重金属含量均超过青海省1990年背景值,其中As、Cd和Hg出现了较强的的富集现象,同时As、Cd超出国家土壤环境质量一级标准,表明三江源区土壤重金属环境自20世纪90年代以来部分元素出现了过度富集;来源分析表明,玉树县土壤重金属As、Pb、Zn和Cd主要与成土因素有关,Hg、Cu和Cr受人类活动影响较大,Mn来源于气候的影响;潜在生态风险评价表明:土壤中Cd和Hg的危害最大,尤其是Hg已出现了很强风险和极强风险,这些风险主要分布在国道214沿线人口聚集的城镇和地段,与人类活动有着密切的关系。在各子流域中,江曲流域土壤重金属属于强风险,其他区域均属于中等风险。总体而言,玉树县土壤重金属环境已发生了改变,今后应加强人口聚集区Hg源的控制,以保护其生态环境。  相似文献   

10.

Purpose

Heavy metals pollution of city soil has become a serious environmental issue. Attention has been given to the issue of soil contamination in big cities, but little research has been done in the Loess Plateau, which is the largest loess deposition area in the world. The aim of this study was to assess the contamination of topsoil.

Materials and methods

Forty soil samples were collected from different districts and sieved through nylon sieves. The coarse particles (2 mm) were used to determine pH and electrical conductivity using a suspension of 1:5 soil to deionized water. The fine particles (150 μm) were used to determine soil organic matter and selected heavy metals. Metals were measured in digested solutions by a flame atomic absorption spectrophotometer.

Results and discussion

The mean concentrations of heavy metals in urban soils in the study area are significantly lower than the mean concentrations across China. The integrated pollution index was determined to be 1.13, indicating moderate pollution. Weathering of parent material, the use of pesticide and fertilizer, discharge of waste from traffic, wastes from commodities and industry, and coal combustion are considered to be the main sources of heavy metal pollution in the study area.

Conclusions

The results indicate that, at least in the study area, land use greatly influences the soil quality and heavy metal contents in urban topsoils. Soil backfill may change heavy metal contents to some extent. Deep digging and backfill can be effectively used for the remediation of heavy metal contaminated soil and sediments.  相似文献   

11.
Phosphorus (P) is necessary for growth and nitrogen fixation, and thus its deficiency is a major factor limiting legume production in most agricultural soils. The effect of phosphorus supply on nodule development and its role in soybeans (Glycine max L.) was studied in a nutrient solution. Plants were inoculated with Bradyrhizobium japonicum and grown for 35 days in a glasshouse at a day and night temperature of 25℃ and 15℃, respectively. Although increasing P supply increased the concentrations of P and N in the shoots and roots, the external P supply did not significantly affect the P concentration in the nodules, and the N fixed per unit nodule biomass decreased with increasing P supply. The nitrogen content in the shoots correlated well with the P content (r=0.92**). At an inoculation level of 10^2 cells mL^-1, the P supply did not affect the number of nodules; however, at inoculation levels of 10^3.5 and 10^5 cells mL^-1, increasing P supply increased both the number and size of nodules. Irrespective of the inoculation level, increasing P supply increased the nodule biomass relative to the biomass of the host plant. It is suggested that the P deficiency specifically inhibited the nodule development and thereby the total N2 fixation.  相似文献   

12.
Heavy metal pollution of urban soils   总被引:1,自引:0,他引:1  
The chemical properties of urban soils (southeastern administrative district, Moscow) affecting the behavior of heavy metals were studied. The current heavy metal pollution level of the soils was assessed. The use of different approaches for the pollution standardization is shown to produce different results. The fractional composition of the metal compounds in the soils and the factors affecting its formation under technogenic pollution were investigated. In the district studied, the distribution of heavy metals by the fractions primarily depended on the chemical properties of the heavy metals themselves; the pollution level; and, to a lesser degree, on the soil properties. Zinc and cadmium were the most mobile metals in the soils studied.  相似文献   

13.
北京市边缘区土壤重金属污染的初步研究   总被引:5,自引:0,他引:5  
基础资料为采集于北京城市边缘区的29个土壤剖面表层和底层58个样品6种重金属全量分析数据,以本区重金属自然土壤元素背景值作为评价标准,计算出各样点剖面表层和底层土壤单因子污染指数。应用对应因子分析手段, 初步揭示了北京市边缘区土壤重金属污染的空间分异特征。结果表明,北京市边缘区土壤重金属总体污染状况不明显,只有Hg元素属于轻微污染范围。不同样点间重金属污染水平比较显示,Hg污染水平差异明显,Pb、Cd、As、Zn、Cu污染差异不大。  相似文献   

14.
不同程度重金属污染对水稻土团聚体组成的影响   总被引:1,自引:1,他引:0  
以太湖地区长期受重金属污染的稻麦轮作条件下的水稻土为研究对象,分别采取水稻收获期和小麦收获期不同重金属污染水平的土壤和临近非污染土壤(对照土壤),利用低能量超声分散分离技术将原状土进行团聚体分级,并结合土壤碳库分析,研究不同程度重金属污染对水稻土团聚体组成的影响。结果表明:随着重金属污染程度的增加,小麦收获期土壤2~0.2 mm与0.2~0.02 mm粒级的团聚体含量呈显著降低趋势,0.02~0.002 mm与0.002 mm粒级团聚体含量显著增加,但这种趋势在水稻收获期表现不显著;重金属污染降低了水稻季团聚体平均重量直径(MWD),从而降低了土壤的团聚程度,但这在小麦季并未表现出显著的降低作用;而小麦季重金属污染对原土及团聚体中有机碳含量没有显著影响,水稻季重金属污染则显著增加了土壤有机碳的含量。这些结果表明不同重金属污染程度对土壤团聚体组成的影响在不同的作物收获期表现不同,这可能与土壤团聚体周转过程受农田水分管理等措施影响有关,尚需深入研究。  相似文献   

15.
Soils of the urban area of Sevilla have been scarcely studied, especially concerning their concentrations of potentially toxic metals. A previous paper has shown that moderate pollution exists in soils from some public green areas of the city, and a common pattern was found in the distribution of the concentrations of some particular metals. The present paper is aimed at (i) determining possible seasonal changes in the measured concentrations; (ii) checking possible effects of the observed pollution on plant metal contents, and (iii) finding possible relations between metals by statistical techniques. Samples of 35 soils from the urban area of Sevilla were studied. Comparison with previous data shows that samples from a depth of 0–20 cm are representative of the measured soil properties for the city. We show that in most cases differences in the EDTA‐ and aqua regia‐extractable metal contents between autumn 2000 and summer 2001 are not significant. Only Zn shows significant decreases (P < 0.05), probably because it is more mobile than the other metals studied. Electrical conductivity and pH also show significant changes related to leaching of soluble salts. We found a strong association between ‘urban’ metals (as defined in the literature) and organic matter, as shown by factor analysis, whereas ‘non‐urban’ metals could be related to clay and carbonate contents, perhaps coming from the soil parent materials. The behaviour of the urban metals means that organic matter contributes to their accumulation, either by retention of the incoming metals from the atmosphere, dust or various human activities, or from addition of organic amendments that might provide significant amounts of such metals. Although concentrations of Cu, Pb and Zn at several sites exceeded the limits established elsewhere as acceptable in residential areas, the values in the grass were less than those considered as normal in the literature. This implies that fairly large concentrations in the soil do not necessarily make metals more available.  相似文献   

16.
我国城市土壤重金属污染研究现状和展望   总被引:20,自引:0,他引:20  
随着我国城市化和工业化的高速发展,城市土壤重金属污染越来越受到关注,本文在文献调研的基础上,比较国内主要城市土壤重金属污染的含量水平,综述了我国城市土壤重金属污染来源、化学形态、分布特点、生态效应等,并提出了研究展望,以期为相关研究、环境决策和环境管理提供参考。  相似文献   

17.
基于GIS的黄淮海平原典型潮土区土壤重金属积累研究   总被引:13,自引:0,他引:13  
夏敏  赵炳梓  张佳宝 《土壤学报》2013,50(4):684-692
以黄淮海平原典型潮土区——河南省封丘县为例,基于GIS数据统计分析方法和地统计学空间插值方法,其目的是为了:(1)明确土壤重金属Cr、Hg、As、Cu、Zn的当前含量水平及其历史变化趋势;(2)通过与潮土自然背景值(背景值)、国家土壤环境质量标准一级标准(一级标准)和绿色食品产地环境质量标准(绿色标准)的比较,阐明各重金属元素符合不同标准的土壤面积及其空间分布;(3)在上述研究基础上采用内梅罗综合指数法定量评价基于一级标准的土壤重金属综合环境质量及其县域分布.结果表明,5种重金属含量平均值除Hg与背景值相当外,其余均略高于背景值而远低于一级标准,除As外,土壤Cr、Hg、Cu、Zn含量均有随年限增加的趋势;占全县土壤总面积98%以上的Cr、As、Zn含量,100%的Hg含量,91%以上的Cu含量符合一级标准,超过99%以上的土壤符合绿色标准;基于一级标准的内梅罗综合指数进一步表明封丘地区土壤综合环境质量良好,仅有不足3%的土壤受到轻度污染.表明就重金属污染角度,当前状况下的封丘土壤适宜种植各类农作物,但个别超过绿色标准的地点应引起重视并及时采取防治措施.  相似文献   

18.
南通市城市边缘带土壤重金属污染现状及评价   总被引:8,自引:0,他引:8  
黄辉  檀满枝  周峰  陈杰  潘根兴 《土壤》2007,39(2):286-290
通过对不同土地利用方式下的7个样区进行系统的采样测定,对南通城市边缘带土壤重金属富集与污染状况进行了分析与评价。结果显示,研究区土壤未发生明显的重金属污染。但3个样区的土壤有轻度的重金属污染现象,Zn是发生富集最普遍的元素,约76%的样点土壤Zn富集指数>1,18%的样点土壤出现Zn的轻度污染。Cu、Pb等重金属元素导致的污染也在零星样点被发现。方差分析表明,土地利用方式不是导致研究区土壤重金属含量空间差异的主要因素,而土壤类型、样区空间环境与土壤重金属含量及富集、污染有相对密切的关系。  相似文献   

19.
Heavy metal contents in forest soils of North Rhine-Westphalia - classification and cartographic evaluation Many forest areas in North Rhine-Westphalia (Germany) are contaminated with heavy metals. To evaluate this pollution of forest soils and its geographical distribution all available literature data on total heavy metal contents in forest soils of North Rhine-Westphalia were included in this study. The results show that an accumulation of heavy metals, especially of Pb, occurred in the litter layer and in the litter layer and in the topsoil. The highest values were measured in the vicinity of industrial areas and at elevated locations such as Egge Mountains and Teutoburger Forest. About 50 % of the samples from the litter layer and the topsoil have pH values below 3. 4. Since the translocation of heavy metals in the soil profile at this low pH increases, potential risk from the mobilization of high stores in the litter layer was estimated for several locations of North Rhine-Westphalia.  相似文献   

20.
水稻子实对不同形态重金属的累积差异及其影响因素分析   总被引:3,自引:0,他引:3  
在分析成都平原核心区土壤重金属(Cd、Cr、Pb、Cu、Zn)全量、各形态含量及相应点位种植的水稻子实重金属含量的基础上,通过统计分析、空间插值及线性回归方程的模拟,研究了土壤Cd、Cr、Pb、Cu、Zn全量的空间分布状况、各形态重金属含量统计特征,以及水稻子实对重金属各形态的累积差异及其影响因素。结果表明,成都平原水稻土重金属污染较轻,除Cd外,均低于国家土壤环境质量二级标准。土壤中重金属的可交换态含量均较低,Cd主要以铁锰氧化态存在,Cr、Cu、Zn、Pb主要以残渣态存在。水稻子实对5种重金属的累积效应顺序为:Cd>Zn>Cu>Pb>Cr。与水稻重金属累积关系密切的重金属活性形态(可交换态、碳酸盐结合态、铁锰氧化物结合态和有机物结合态)主要有:Cd的碳酸盐结合态、Cr的可交换态、Pb的有机物结合态和Cu的碳酸盐结合态含量;Zn各活性形态对水稻子实含量的影响不明显。土壤理化性质对不同活性形态重金属元素的影响效应各不相同。活性态Cd主要受有机质、pH和容重的影响;活性态Cr与pH、有机质、CEC和容重密切相关;活性态Pb与有机质、容重、中细粉粒、砂粒等均有密切的关系;Cu的活性主要受粘粒、有机质含量的影响;Zn的有效性主要受pH、有机质、砂粒、容重的影响。总的看来,对土壤Cd、Cr、Pb、Cu、Zn各活性形态含量影响效应较强的是有机质、pH、容重,而与土壤吸附性能密切相关的颗粒组成、CEC的影响不甚明显。  相似文献   

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