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1.
北京城乡交错带土壤重金属的空间变异特征   总被引：22，自引：0，他引：22  
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2.
A field experiment with cotton was conducted on a well drained,calcareous,clay loamy Typic Xerochreph to investigate the utility of sewage sludge as a partial substitute for fertilizers and the influence of tis application on the basic soil properties and heavy metal concentrations.The experimental design was completely randomized blocks with five treatments replicated four times each.Sewage sludge came from the treatment plant of the municipality of Volos,Central Greece,with the following characteristics:organic matter content 36.6%,pH(H2O1:5)6.89,CaCO3 53.4g kg^-1,total N 265.g kg^-1,ttal P33.5g kg^-1,and total K 968mg kg^-1 soil.Heavy metal concentrations were Cd 5.24,Pb 442,Ni38,Cu 224,Zn1812,and Mn 260mgkg^-1 dry weight,respectively.The soil was high in potassium(K)and poor in available phosphorus(P).The results showed that sewage sludge application increased cotton yield and K and P concentrations in cotton leaves,Soil pH was reduced in the case of higher sewage sludge rate.Electrical conductivity,organic matter content,totalN,and avaiable P were significantly increased.Total concentrations of Zn,Pb,and Cu were slightly increased.DTPA-extractable Zn,Cu,and Mn were also significantly increased.Available forms of all heavy metals,except Cd,were significantly correlated with organic matter content in a positive way and negatively with soil pH.  相似文献   

3.
Soil contamination by heavy metals is a problem in agricultural irrigation systems.To assess the accumulation and sources of heavy metals in the Yongji irrigation district of the Hetao area,Inner Mongolia,China,195 soil samples from 39 sites(0–100 cm)were collected,and Zn,Cu,Pb,Cr,and Cd concentrations were analyzed.The mean concentrations were 107.17,32.48,12.31,53.53,and 0.22 mg kg-1,respectively,with no significant differences between soil depths(P>0.05).Concentrations of Zn,Cu,and Cd were higher than the background levels,with moderate accumulation;the contamination factor(CF)values were 1.9,1.7,and 1.9,respectively,and the geoaccumulation index(Igeo)was>0.Concentrations of Pb and Cr were lower than,or close to,the background levels(CF<1,Igeo<0),indicating that they originated from a natural source.The monomial potential ecological risk index(Eri)for Zn,Cu,Pb,and Cr was low;Eri for Cd was 55.73,implying a moderate risk.The grade of potential ecological risk index of the five heavy metals(RI)was low,declining from south to north.The studied soils were contaminated with Zn,Cu,and Cd;principal component(PC)analysis implicated the enrichment of Cd and partial Cu(high loading in PC 2)was related to agricultural activities;Zn and partial Cu,closely associated with PC 3,may have originated from irrigation water from the Yellow River.Future agricultural development should focus on fertilizer and pesticide application and the quality of irrigation water.  相似文献   

4.
中国太原市农业土壤的重金属污染状况   总被引：5，自引：0，他引：5  
To evaluate the current state of the environmental quality of agricultural soils in Taiyuan City, a hotspot for China’s industrial development, the concentrations of 8 heavy metals in soils were investigated by means of extensive sampling in farmlands, forestlands, and grasslands in the city. Statistical analyses and spatial distribution maps were used to identify the most significant heavy metal pollutants. The mean concentrations of As, Cd, Cu, Hg, Pb, Zn, Ni, and Cr were slightly higher than their background values in Taiyuan’s topsoil, but were lower than the maximum permissible concentrations in the Chinese Environmental Quality Standard for agricultural soils. Farmland soils in Taiyuan had the highest average Cd, Cu, Hg, Pb, Zn, and Cr concentrations, but the As and Ni concentrations did not differ significantly among the farmland, forestland, and grasslands. Soil contamination by Cd, Cu, Hg, Pb, Zn, and Cr was mainly derived from farming practices, especially the use of sewage water for irrigation. In contrast, As and Ni might derive mainly from the soil parent material. The identification of heavy metal sources in agricultural soils may provide a basis for taking appropriate action to protect soil quality.  相似文献   

5.
中国五个典型城市污水厂污泥中重金属的形态分布研究   总被引：3，自引：0，他引：3  
Metal content and bioavailability are often the limiting factors for application of sewage sludge in agricultural fields. Sewage sludge samples were collected from five typical urban wastewater treatment plants in China to investigate their contents and distribution of various chemical fractions of Cu, Zn, Ni, Cr, Pb and Mo by using the BCR （Community Bureau of Reference） sequential extraction procedure. The sludges contained considerable amounts of organic matter （31.8%- 48.0%）, total N （16.3-26.4 g kg^-1） and total P （15.1-23.9 g kg^-1）, indicating high potential agricultural benefits of their practical applications. However, total Zn and Ni contents in the sludge exceeded the values permitted in China＇s control standards for pollutants in sludges from agricultural use （GB 4284-1984）. The residual fraction was the predominant fraction for Mo, Ni and Cr, the oxidizable fraction was the primary fraction for Cu and Pb, and the exchangeable and reducible fractions were principal for Zn. The distribution of different chemical fractions among the sludge samples refiected differences in their physicochemical properties, especially pH. The sludge pH was negatively correlated with the percentages of reducible fraction of Cu and exchangeable fraction of Zn. The sludges from these plants might not be suitable for agricultural applications due to their high contents of Zn, Ni and Cr, as well as high potential of mobility and bioavailability of Zn.  相似文献   

6.
Physicochemical properties, total and DTPA （diethylenetriaminepentaacetic acid）-extractable Cu, Zn, Pb and Cd contents, microbial biomass carbon （C） content and the organic C mineralization rate of the soils in a long-term trace metal-contaminated paddy region of Guangdong, China were determined to assess the sensitivity of microbial indices to moderately metal-contaminated paddy soils. The mean contents of total Cu, Zn, Pb and Cd were 251, 250, 171, and 2.4 mg kg^-1 respectively. DTPA-extractable metals were correlated positively and significantly with total metals, CEC, and organic C （except for DTPA-extractable Cd）, while they were negatively and highly significantly correlated with pH, totall Fe and Mn. Metal stress resulted in relatively low ratios of microbial biomass C to organic C and in remarkable inhibition of the microbial metabolic quotient and C mineralization rate, which eventually led to increases in soil organic C and C/N. Moreover, microbial respiratory activity showed a stronger correlation to DTPA-extractable metals than to total metal content. Likewise, in the acid paddy soils some “linked” microbial activity indices, such as metabolic quotient and ratios of basal respiration to organic C, especially during initial incubation, were found to be more sensitive indicators of soil trace metal contamination than microbial biomass C or basal respiration alone.  相似文献   

7.
化学萃取修复尾渣土壤的金属形态变化特征   总被引：4，自引：0，他引：4  
The efficiency of EDTA, HNO3 and CaCl2 as extractants to remove Pb, Zn and Cu from tailing soils without varying soil pH was investigated with distributions of Pb, Zn and Cu being determined before and after extraction using the sequential extraction procedure of the optimized European Community Bureau of Reference （BCR）. Results indicated that EDTA and HNO3 were both effective extracting agents.The extractability of extractants for Pb and Zn was in the order EDTA 〉 HNO3 〉 CaCl2, while for Cu it was HNO3 〉 EDTA 〉 CaCl2. After EDTA extraction, the proportion of Pb, Zn and Cu in the four fractions varied greatly, which was related to the strong extraction and complexation ability. Before and after extraction with HNO3 and CaCl2, the percentages of Pb, Zn and Cu in the reducible, oxidizable and residual fractions changed little compared to the acid-extractable fraction. The lability of metal in the soil and the kinds of extractants were the factors controlling the effects of metal extraction.  相似文献   

8.
oil P status, inorganic P fractions, and P sorption properties were studied using sandy fluvo-aquic horticultural soils,which are high in organic matter content for vegetable production in comparison with a soil used for grain crop productionin Zhengzhou, Henan Province, China. P fractions, Olsen-P, and OM were determined at different depths in the soilprofile and sorption isotherm experiments were performed. Most P in excess of plant requirements accumulated in thetopsoil and decreased with soil depth. Total P, inorganic P, and OM concentrations increased with continued horticulturaluse.Olsen-P concentrations in the 0-20 cm depth of horticultural soils were 9 to 25 times higher than those of the graincrop soil. A linear transformation of the Langmuir equation showed that the P adsorption maximum (491.3 mg P kg^-1)and the maximum phosphate buffering capacity (162.1 L kg^-1) for 80-100 cm were greater in the grain crop soil than thehorticultural soils. Thus, the most immediate concern with excess P were in areas where heavy P fertilizer was used forvegetable crops and where soil P sorption capacities were low due to sandy soils and high organic matter content.  相似文献   

9.
三峡库区坡地表层风化特征研究   总被引：2，自引：0，他引：2  
Extractability and mobility of Cu and Zn and their relationships with 1） accumulation of Cu and Zn and 2） soil pH were studied in three sandy soils （Wabasso, Ankona, and Winder） from commercial citrus groves in Florida, USA. The soils, with a broad range of Cu and Zn concentrations, were fractionated by a modified procedure of Amacher, while Cu and Zn mobility were evaluated using column leaching. The extractability of Cu and Zn increased with decreasing soil pH. Also with increasing total soil Cu and Zn for extractable Cu in the Wabasso sand a threshold level, where the metal extraction rate increased, was noted at 100 mg kg^-1, whereas for extractable Zn in the Wabasso sand the threshold level was found at 60 mg kg^-1 and in the Ankona sand at 120 mg kg^-1. These results suggested that the release potential of Cu and Zn was greater in the Wabasso sand than in the Ankona sand. The column leaching experiment showed that at total soil Cu or Zn concentrations 〈 100 mg kg^-1 all leachates had low Cu and Zn concentrations. However at total concentrations 〉 200 mg kg^-1 for Cu and 〉 150 mg kg^-1 for Zn with decreasing soil pH, the concentrations of both Cu and Zn in the leachates increased exponentially. Also in these sandy soils soluble Cu and Zn mainly originated from the exchangeable fractions, and pH was a key factor controlling Cu and Zn extractability and mobility.  相似文献   

10.
Physicochemical properties, total and DTPA (diethylenetriaminepentaacetic acid)-extractable Cu, Zn, Pb and Cd contents, microbial biomass carbon (C) content and the organic C mineralization rate of the soils in a long-term trace metal-contaminated paddy region of Guangdong, China were determined to assess the sensitivity of microbial indices to moderately metal-contaminated paddy soils. The mean contents of total Cu, Zn, Pb and Cd were 251, 250, 171, and 2.4 mg kg-1 respectively. DTPA-extractablc metals were correlated positively and significantly with total metals, CEC, and organic C (except for DTPA-extractable Cd), while they were negatively and highly significantly correlated with pH, total Fe and Mn. Metal stress resulted in relatively low ratios of microbial biomass C to organic C and in remarkable inhibition of the microbial metabolic quotient and C minera]ization rate, which eventually led to increases in soil organic C and C/N. Moreover, microbial respiratory activity showed a stronger correlation to DTPA-extractable metals than to total metal content. Likewise, in the acid paddy soils some "linked" microbial activity indices, such as metabolic quotient and ratios of basal respiration to organic C, especially during initial incubation, were found to be more sensitive indicators of soil trace metal contamination than microbial biomass C or basal respiration alone.  相似文献   

11.
闽西南崩岗土壤重金属含量、分布、来源及生态风险   总被引：2，自引：1，他引：1  
选取福建省长汀县黄泥坑崩岗群内2处典型崩岗及附近一无崩岗山坡(对照区),采样并测定了63份0~20 cm土壤样品Cu、Zn、Ni、Pb、Cr、As、Cd含量,运用相关分析与主成分分析进行重金属来源辨识,并应用Hankanson潜在生态风险指数法,以福建省背景值和国家二级标准作为参比,对研究区重金属进行潜在生态风险评价。结果表明:研究区土壤重金属含量从高到低的顺序依次为Zn(105.56 mg·kg~(-1))Pb(67.21 mg·kg~(-1))As(61.47 mg·kg~(-1))Cu(22.33 mg·kg~(-1))Cr(17.12 mg·kg~(-1))Ni(5.24 mg·kg~(-1))Cd(0.80 mg·kg~(-1)),Pb、Cd含量表现为崩岗区对照区,Cu、Zn、Ni、Cr、As、Cd含量与之相反。1号崩岗Zn、Pb、As和Cd平均值分别是福建省背景值的1.12倍、2.82倍、8.68倍和13.33倍,2号崩岗这4种元素平均值分别是背景值的1.11倍、1.36倍、11.22倍和16.67倍,对照区该4种元素平均值分别是背景值的1.58倍、1.60倍、5.14倍和14.44倍;与国家土壤环境质量二级标准比较得出,崩岗区和对照区As平均值分别超标1.92倍和2.70倍,Cd平均值分别超标2.31倍和2.60倍。从集水坡面到沟道末端,崩岗区Pb、Zn、Cd含量呈增加趋势,Cu、Cr含量基本维持稳定,Ni含量有所降低;从坡面上部到下部,对照区Cu、Zn、Ni、Cr、Cd含量呈增加趋势,Pb含量略有降低;As含量在研究区的分布无明显变化。Cu、Ni、Cr主要来源为成土母质,Zn主要来源于禽畜养殖,Cd、As的主要来源包基岩风化稀土开采,Pb主要来源于基岩矿化、煤炭燃烧及汽车尾气排放等复合污染源。以福建省背景值为参比时,Cd潜在生态风险系数达到"极强风险",As为"较强风险",其余均为"轻微风险";以国家二级标准为参比时,Cd属"较强风险",其余均为"轻微风险"。潜在生态风险指数(Ri)表现为2号崩岗对照区1号崩岗。研究区Cd、As污染已较为严重,应采取相应的安全防范措施。  相似文献   

12.
在北京顺义区采集了412份土壤表层样品,分析了其中7种重金属元素（Cu、Zn、Cr、Pb、Cd、As和Hg）的全量,采用单因子指数和内梅罗指数对土壤环境质量进行评价。结果表明,土样中As、Cd、Cr、Hg、Cu、Pb和Zn含量平均值分别为7.85、0.136、61.47、0.073、22.43、20.38mg.kg-1和69.75mg.kg-1,As、Cd、Cr、Cu和Zn含量平均值超过了北京地区环境背景值,但所有元素含量的平均值均未超出土壤环境质量一级标准。土壤中各重金属元素含量Shapiro-Wilk检验和相关性检验结果表明,研究区土壤中重金属Cr呈正态分布,Cd、Cr、Cu、Pb元素与As元素相关性显著。土壤各元素单因子污染指数排序为Zn〉Cr〉Cd〉Cu〉Pb〉As〉Hg,内梅罗综合污染指数平均值为0.745,达到了土壤环境质量评价分级标准Ⅱ级,污染等级为＂警戒线＂级;菜地、果园、荒地、林地、苗圃、设施农业用地和水浇地的土壤内梅罗指数分别为0.809、0.765、0.720、0.669、0.781、0.786和0.729,表现为菜地〉设施农业〉苗圃〉果园〉水浇地〉荒地〉林地。土壤环境质量总体安全,部分地区土壤重金属污染处于警戒水平。  相似文献   

13.
对天水果园表层（0~20 cm）219件土壤样品进行研究,测定5种重金属（Zn、Cu、Pb、Cr和Cd）及有机质含量,以天水小陇山土壤为对照,运用相关分析和主成分分析方法区分土壤中重金属的来源。结果表明,①Zn、Cu、Pb、Cr和Cd含量分别为77.39、23.03、23.62、61.49 mg.kg-1和0.07 mg.kg-1,其中Cd极显著（P〈0.01）高于小陇山土壤,其余4种重金属虽高于小陇山土壤但无显著差异性（P〉0.05）;②研究区土壤Cu、Pb、Cr三者间在0.01或0.001水平上具有显著正相关性,且这3种重金属与土壤有机质具有显著正相关性,其余重金属间不存在显著相关性;③主成分分析显示Cu、Pb和Cr来源相似,主要来自于成土母质,Cd来源于人为施肥因素,Zn的富集受多种因素影响。研究评价结果显示,天水地区果园土壤Cd受人为施肥影响较大,具有一定程度的富集。  相似文献   

14.
We investigate the potential of near-infrared (NIR) spectroscopy to predict some heavy metals content (Zn, Cu, Pb, Cr and Ni) in several soil types in Stara Zagora Region, South Bulgaria, as affected by the size of calibration set using partial least squares (PLS) regression models. A total of 124 soil samples from the 0–20 and 20–40 cm layers were collected from fields with different cropping systems. Total Zn, Cu, Pb, Cr and Ni concentrations were determined by Atomic Absorption Spectrometry. Spectra of air dried soil samples were obtained using an FT-NIR Spectrometer (spectral range 700–2,500 nm). PLS calibration models were developed with full-cross-validation using calibration sets of 90 %, 80 %, 70 % and 60 % of the 124 samples. These models were validated with the same prediction set of 12 samples. The validation of the NIR models showed Cu to be best predicted with NIR spectroscopy. Less accurate prediction was observed for Zn, Pb and Ni, which was classified as possible to distinguish between high and low concentrations and as approximate quantitative. The worst model performance in cross-validation and prediction was for Cr. Results also showed that values of root mean square error in cross-validation (RMSEcv) increased with decreasing number of samples in calibration sets, which was particularly clear for Cu, Pb, Ni and Cr content. A similar tendency was observed in the prediction sets, where RMSEP values increased with a decrease in the number of samples, particularly for Pb, Ni and Cr content. This tendency was not clear for Zn, while even an increase in RMSEP for Cu with the sample size was observed. It can be concluded that NIR spectroscopy can be used to measure heavy metals in a sample set with different soil type, when sufficient number of soil samples (depending on variability) is used in the calibration set.  相似文献   

15.
土壤可见光-近红外反射光谱与重金属含量之间的相关性   总被引：13，自引：0，他引：13  
解宪丽  孙波  郝红涛 《土壤学报》2007,44(6):982-993
发展基于反射光谱技术的快速、简便、低成本的土壤重金属信息提取方法是区域土壤重金属污染治理所需要的。选择江西贵溪铜冶炼厂污染区,分析了9种重金属元素(Cu、Pb、Zn、Cd、Co、Ni、Fe、Mn及Cr)与土壤可见光-近红外反射光谱之间的相关性及其相关的原因。研究表明,研究区土壤中存在Cu(含量介于66.71~387 mg kg-1之间)和Cd(含量介于0.36~6.019 mg kg-1之间)的强烈富集。土壤重金属含量与反射光谱之间存在显著相关,污染元素Cu的最高相关系数为-0.87,Pb、Zn、Co、Ni、Fe的最高相关系数达到高度相关(|r|>0.80),Cr、Cd、Mn的最高相关系数达到显著相关(|r|>0.70)。微分光谱适于获取土壤中的重金属元素信息,利用组合波段能显著提高相关性。Cu与反射光谱之间的相关性主要受有机质的影响;Pb、Zn、Co、Ni主要受黏土矿物和铁锰氧化物的影响;Cr与反射光谱之间的相关性同时受有机质和黏土矿物的影响。  相似文献   

16.
工业区周边农田重金属污染评价及来源分析   总被引：4，自引：0，他引：4  
以新疆北疆某工业区周边农田土壤为研究对象,采集0~20 cm土壤样品254个,测定了Cr、Ni、Cu、Zn、As、Hg、Pb、Cd共8种重金属含量。运用相关性分析和主成分分析探讨工业区周边农田土壤重金属的来源,运用GS+进行数据拟合,选取最佳模型,再进行克里格插值分析重金属的空间分布格局。结果表明,Cr、Ni、Cu、Zn、As、Hg、Pb和Cd的含量分别为45.00、28.53、55.66、73.57、13.39、2.17、15.38和0.50 mg kg~(-1)。测量的金属除Cr之外均超过土壤的背景值,只有Hg处于中度污染,其余元素都处于非污染,而研究区综合潜在生态风险程度为严重型。重金属空间分布表明,Ni、Zn、As、Hg和Pb在东部和南部含量较高。来源分析表明,Hg来源受研究区内工业活动的影响;Cr、Ni、Zn和Cd主要来自于化肥、农药和地膜等农业活动和土壤母质的共同作用;As、Hg和Pb主要来源是受研究区内工业活动的影响。  相似文献   

17.
新疆奎屯垦区土壤重金属风险评价   总被引：9，自引：0，他引：9  
采用网格法采样,对新疆奎屯垦区3个团场土壤中As、Pb、Cu、Cd、Cr和Ni含量进行了测定,系统分析了该地区土壤重金属的含量水平、潜在生态风险程度、主要污染因子和污染来源。结果表明:奎屯垦区土壤重金属As、Pb、Cd、Cu、Cr、Ni的平均值分别为20.21 mg kg-1、35.91 mg kg-1、0.40 mg kg-1、27.18 mg kg-1、77.02 mg kg-1、39.31 mg kg-1,均没有超过国家土壤环境质量二级标准,但As、Cd有个别样点超标。各元素平均含量值均超过新疆土壤背景值,其中Cd、As、Pb最为显著,呈现出累积趋势。各重金属潜在生态风险由高至低顺序为Cd>As>Pb>Ni>Cu>Cr,其中Cd为主要潜在生态风险因子。进一步相关分析和因子分析结果显示,各元素的来源可分为两类,Cd、Pb和As为一类,来源主要受各种人为活动影响,Cu、Cr、Ni为一类,来源主要与成土母质有关。  相似文献   

18.
长期污灌农田土壤重金属污染及潜在环境风险评价   总被引：1，自引：0，他引：1  
以西安市某典型污灌区农田土壤为研究对象,分析长期污水灌溉对表层土壤重金属含量及富集状况的影响,采用内梅罗指数法和Hakanson潜在生态危害指数法对其污染现状及潜在环境风险进行评价。结果表明：长期污灌已导致农田土壤Cd、Cr、Cu、Hg、Ni、Pb和Zn7种重金属相对自然背景有不同程度累积,其富集比例依次为100%、82.69%、100%、100%、80.77%、98.08%和100%,仅有土壤As平均含量低于其背景水平;以国家土壤环境质量标准二级限量值作为污染评价阈值,其中Cd和Hg污染表现突出,按其污染指数平均值排序为Cd〉Hg〉Ni〉Cu〉Zn〉As〉Cr〉Pb;土壤重金属综合潜在环境风险为＂强＂等级,Hg、Cd的环境影响占据主导;随污灌年限增长,离灌渠越近,农田土壤重金属的污染水平和环境风险越高。鉴于该区土壤重金属已呈现较强生态危害性,应及时采取必要防治措施,调整土地利用结构,确保农田环境及农产品安全生产。  相似文献   

19.
规模化猪场区域农田土壤重金属积累及影响评价分析   总被引：2，自引：0，他引：2  
为了解长期灌溉猪场废水对农田土壤重金属的影响,采集了河北省京安猪场区域农田清洁区和灌溉8年猪场废水污灌区的耕层(0～20 cm)共52个土壤样品,并测定了样品的pH、养分和Zn、Cu、Cr、Ni、Pb和As全量和有效态含量,根据背景资料、相关分析和主成分分析确定重金属污染来源,应用富集因子分析重金属积累程度,并应用污染指数进行重金属影响评价分析。结果表明,灌溉猪场废水对土壤主要带来Zn和Cu的富集,对Ni、Cr和As几乎没有富集效应,Pb和As的富集主要由施用化肥引起。尽管灌溉8年猪场废水后土壤的Zn、Cu、Cr、Ni、Pb和As含量在安全范围内,但土壤重金属有效态含量不仅与重金属全量正相关,还与土壤pH负相关,而灌溉猪场废水会降低土壤pH,从而增加土壤重金属有效态含量。因此,长期灌溉猪场废水不但要注意土壤Zn和Cu积累,还需采取措施降低土壤Zn、Cu等重金属有效态含量以防重金属带来环境风险。  相似文献   

20.
以三江源区玉树县和玛多县为研究区,利用实验室测定的As、Cu、Pb、Zn、Cr、Cd、Hg元素含量和室内采集的土壤原始光谱及其4种转换形式,建立了光谱指标与重金属含量的多元回归模型,利用决定系数(R2)、相对分析误差(RPD)及均方根误差(RMSE)评价模型的精度。研究结果表明,土壤As、Cu、Pb、Zn、Cr、Cd含量与SOM、Fe、Mn、Al、Mg等元素具有显著相关关系,Hg元素则未达到显著性水平。As、Cu、Pb、Zn、Cr和Cd元素估算模型回归方程R2达到了0.5以上,均通过了显著性检验,其中Pb、Zn和Cr元素验证样本RPD均达到了1.4以上,模型具备粗略估算能力;As、Cu和Cd元素验证样本RPD均低于1.4,模型不具备粗略估算能力。Hg元素估算模型回归方程的R2为0.28,未能通过显著性检验,无法用于对Hg含量的估算。  相似文献   

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