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1.
Long-term irrigation with municipal wastewater may lead, even in spite of intense farming, to an accumulation of organic matter, nutrient elements, and trace metals in soils. Excessive increases of heavy metals may pose a potential risk to the food chain and provoke restrictions for the further cultivation of sensitive crops. Copper (Cu), zinc (Zn), and lead (Pb) forms in soils under long-term irrigation (for 100–120 years) with treated wastewater of Wroclaw were investigated by using selective seven-step sequential extraction (procedure of Zeien-Bruemmer) for partitioning the metals into operationally defined fractions, likely to be released in solution under various environmental conditions. The largest fraction of Cu, Pb, and particularly Zn in nonirrigated (control) soils was strongly bound in a residual form, while the percentage of exchangeable and the most labile fractions were negligible. Total concentration of metals in irrigated soils was elevated, and significant redistribution of metals among phases was observed. Percentages of residual fraction of Cu and Pb were no more than 25% (Zn < 40%), while significantly increased contribution of fractions occluded on iron (Fe) oxides and organically bound Cu. Exchangeable and readily mobile forms of Zn are predominant zinc fractions in soils irrigated with wastewater.  相似文献   

2.
Soil samples were collected from Zhangshi Wastewater Irrigation Area in the suburb of Shenyang City, China, an area with a 30-year irrigation history with heavy metal-containing wastewater. The chemical properties and microbial characteristics of the soils were examined to evaluate the present situation of heavy metal pollution and to assess the soil microbial characteristics under long-term heavy metal stress. In light of the National Environmental Quality Standards of China, the soil in the test area was heavily polluted by Cd and to a lesser degree by Zn and Cu, even though wastewater irrigation ceased in 1993. Soil metabolic quotient (qCO2) had a significant positive correlation, while soil microbial quotient (qM) had a negative correlation with content of soil heavy metals. Soil microbial biomass carbon (MBC) had significantly negative correlation with Cd, but soil substrate~induced respiration (SIR), dehydrogenase activity (DHA), cellulase activity, and culturable microbial populations had no persistent correlations with soil heavy metal content. Soil nutrients, except for phosphorous, showed positive effects on soil microbial characteristics, which to a certain degree obscured the adverse effects of soil heavy metals. Soil Cd contributed more to the soil microbial characteristics, but qM and qCO2 were more sensitive and showed persistent responses to heavy metals stress. It could be concluded that qM and qCO2 can be used as bioindicators of heavy metal pollution in soils.  相似文献   

3.
The accumulation of heavy metals in the soils of the Braunschweig wastewater irrigation area The concentration of lead, zink and cadmium in the Ap-horizons and subsoils of sandy Podzols and Cambisols were investigated. As compared with same soils outside the irrigation area an accumulation of the heavy metals in the Ap-horizons of the older sprinkler irrigation plots was found. On the rill irrigation area the heavy metals also were concentrated in the subsoils.  相似文献   

4.
为了解岷江下游(五通桥段)土壤污染特征及其生态风险,采用野外采样及室内测试方法分析了岷江下游(五通桥段)103个土壤样品中的农药残留量和重金属含量。结果表明,全部样品中六六六(HcHs)含量符合国家二级标准(500μg·kg-1),大部分样品中滴滴涕(DDTs)含量符合国家二级标准,有机磷农药(OPPs)杀螟硫磷(60.40%)和溴硫磷(55.45%)超标率较高,重金属cd的地积累指数高达2.79。有机氯农药(OCPs)禁用20a后在区内的降解程度较高,OPPs在土壤中的大量残留是由于农药的无序使用,外源输入是导致重金属污染的主要原因。区内农药残留和重金属污染范围广,复合污染较严重,存在较大的生态风险。  相似文献   

5.
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   

6.
This study evaluated the physicochemical changes in the soil of potato field that was irrigated by fresh water, differentially diluted wastewater and undiluted wastewater (hereafter called wastewater). The potato crop was cultivated for consecutive three seasons under fertilized and unfertilized conditions. The wastewater contained higher concentrations of organic carbon (C), nitrogen (N), phosphorus (P), potassium (K), sodium (Na), calcium (Ca), magnesium (Mg), sulfur (S), zinc (Zn) and boron (B) and lower concentrations of heavy metals. In this study, properties of wastewater-irrigated soil were compared with fresh water-irrigated soil. The application of wastewater reduced the bulk density of the surface soil by 2.83% and augmented the porosity by 6.02%. The unsaturated hydraulic conductivity and water retention capacity of the soil were improved under wastewater irrigation. Soil pH increased due to wastewater application but decreased, to a smaller extent, due to fertilizer application. Soil EC increased both with wastewater and fertilizer application; both parameters changed significantly in the top 0–15 cm soil layer. But, at the deeper layers, they were not affected by wastewater application. The organic C, total N, available P and S of the soils increased significantly (p = 0.05) when potato field was irrigated with raw wastewater. The organic C increased by 23.80% under wastewater irrigation in the top soil layer. The N content of the soil showed similarities with the organic C contents. Exchangeable Na, K, Ca, Mg; Zn and B of the soil also increased significantly with wastewater application. So, irrigation with urban wastewater is suggested to improve soil fertility as well as to ease pressure on the fresh water in the area of water scarcity.  相似文献   

7.
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   

8.
Since the beginning of this century, wastewater has been utilized for crop production in the Mexican Valley of Mezquital; however, few data are available for evaluating the level of heavy metal pollution in that region. Waters, soils and plants were sampled in different sites, representing three specific irrigation sources in the valley. Trace metals were determined in all samples. Total amount of most trace metals in raw municipal wastewater, and that of Ni, Cr, Pb and Zn in diluted water were quite high. Wastewater irrigation markedly increased the amounts of trace elements extracted from soils by 4M HNO3; the amounts of metals were proportional to the amount of wastewater applied. Copper, chromium, and lead concentrations in soils roughly paralleled their organic matter contents. A wide range in tissue concentration of metals was observed. Zinc was the most metal absorbed by alfalfa and oats. Levels of Ni and Pb in plants, and to some extent, those of Co and Cu, were increased by raw wastewater irrigation. Chromium and lead accumulations in alfalfa were well above the tolerance levels suggested by some workers and the high Co concentration found in this legume may be a health risk for animals and human beings.  相似文献   

9.
周秀艳  李培军  孙洪雨 《土壤》2006,38(2):192-195
对辽宁省几个典型工矿区以及污灌区土壤重金属污染状况进行调查研究,结果表明:调查区土壤重金属含量绝大多数高于土壤背景值,尤其工矿区附近土壤Cd、Pb、Cu和污灌区的Cd、Hg的污染状况应该引起足够的重视;重金属元素间存在着一定的伴生规律;土壤中重金属污染物主要来源于工矿开发、废岩、尾矿泥、大气飘尘以及污水灌溉等。  相似文献   

10.
三峡库区典型农业区土壤重金属污染特征及风险评价   总被引:4,自引:4,他引:0  
为了解三峡库区农业区土壤重金属污染现状及环境风险水平,该文以重庆市8个典型农业区县(铜梁、云阳、万州、丰都、城口、垫江、南川和江津)土壤为研究对象,共采集表层(0~20 cm)土壤样品160个,依照《土壤环境监测技术规范(HJ/T 166-2004)》和《土壤环境质量标准GB 15618-1995》分析了土壤样品中8种重金属(As、Cd、Cr、Cu、Hg、Ni、Pb和Zn)的含量,比较了不同区县8种重金属污染现状及差异,应用地积累指数法和潜在生态风险指数法探讨了研究区土壤重金属的累积特征及潜在生态风险等级。结果表明:该研究区农业土壤8种重金属含量平均值均未超过《土壤环境质量标准GB 15618-1995》二级标准,与土壤背景值相比,Cd、Cr、Cu、Hg和Zn均具有极显著差异(P0.01),As、Ni和Pb差异不显著,8个区县Cr均表现出极显著差异(P0.01),城口区多种重金属均表现出极显著差异(P0.01),8种重金属地累积指数平均值均小于0,研究区土壤受重金属污染水平为未污染等级,单个重金属潜在生态风险顺序为HgCdAsHgCuNiCrZn,Hg元素潜在生态风险指数平均值为43.840,属中等生态风险等级,其余元素生态风险指数值均小于40,属于低生态风险等级,8种重金属综合潜在生态风险指数平均值为108135,为低生态风险等级。综合研究结果表明:三峡库区典型农业区土壤Cd、Cr、Cu、Hg和Zn具有一定程度的累积,且表现为多种重金属复合累积现象,Cr累积具有普遍性,Hg是影响三峡库区农业土壤综合潜在生态风险的主要元素,但研究区土壤重金属总体处于低生态风险水平。  相似文献   

11.
采用现场采样及室内测试方法对沈抚灌区农田土壤中Cu、Hg、Ni和Cd等重金属的含量进行了测定分析,利用污染指数法对灌区土壤环境质量进行了评价,并应用美国环保局推荐的健康风险评价模型对灌区土壤重金属通过土壤摄食途径所引起的健康风险作了初步评价。结果表明,灌区土壤中重金属的平均浓度范围分别为Cu:22.1~40.8mg·kg^-1,Hg:0.036-0.310mg·kg^-1,Ni:29.8~44.4mg·kg^-1,Cd:0.145~0.956mg·kg^-1。4种重金属浓度平均值大小为Ni〉Cu〉Cd〉Hg;土壤中Cu、Hg、Ni和Cd所引起的成人和儿童的平均个人风险均低于可接受水平10^-6,且在这两类调查人群中,健康风险大小顺序均为Cd〉Ni〉Hg〉Cu;儿童比成人更易受到土壤重金属的影响,致癌风险是成年的3倍;灌区土壤环境质量环境评价结果显示,灌区土壤重金属污染处于轻微水平。  相似文献   

12.
A total of 50 farmland soil samples were collected from the Yanqi County, Xinjiang, China, and the concentrations of eight heavy metal elements (As, Cd, Cr, Cu, Mn, Ni, Pb and Zn) were determined by standard methods. The spatial distribution, pollution level and ecological risk status of heavy metals were analyzed based on GIS technology, the Geo-accumulation Index (Igeo), the Pollution Load Index (PLI) and the Potential Ecological Risk Index (RI). Results indicated that: (1) The average contents of Cd, Cr, Ni, Pb, and Zn of farmland soils exceeded the background values of irrigation soils in Xinjiang by 1.5, 1.40, 1.33, 2.63, and 4.92 times, respectively. Cd showed a no-pollution level, Zn showed a partially moderate pollution level, Pb showed a slight pollution level, and Cr, Cu, As, Mn, and Ni showed no-pollution level, compared to the classification standard. The PLI values of heavy metal elements of farmland soils varied from 0.83 to 1.89, with an average value of 1.29, at the moderate pollution level. (2) The Individual Potential Ecological Risk Index for heavy metals in the study area was ranked in the order of: As > Ni > Cu > Cd > Pb > Cr> Zn. The RI values of heavy metals of farmland soils varied from 3.45 to 11.34, with an average value of 6.13, at the low ecological risk level. (3) Cu and Mn of farmland soils were mainly originated from the soil parent material and topography of the study area. As, Cd, Ni and Pb were mainly originated from human activities, and Cr and Zn may originated from both natural and anthropogenic factors in the study area.  相似文献   

13.
拉林河流域土壤重金属污染特征及来源解析   总被引:10,自引:2,他引:8  
该文选取拉林河流域表层土壤为研究对象,通过对土壤重金属的含量和空间分布分析、污染评价、以及潜在生态风险评价,了解土壤重金属的分布特征和污染现状,并利用正定矩阵因子分解法(PMF)探索土壤重金属污染的来源。结果表明,表层土壤中Cr、As、Pb、Cu、Zn、Ni、Mn、V的平均含量均低于背景值,Co和Se略微高于背景值,部分土壤样点Cd和Ni超过国家土壤环境质量标准的二级标准。研究区土壤污染的主要金属元素为Cd和Hg,地累积指数表明受到污染的样品比例分别达到45.1%和37.0%,其潜在生态危害指数平均值分别为49.83和70.29。根据PMF计算结果,拉林河流域表层土壤重金属累积主要受自然源、农药肥料源、工业排放源的影响。其中,自然本底对研究区土壤中重金属的影响最大,贡献率为38.0%,其次是农药和肥料施用,贡献率为32.6%,燃煤和工业排放源的贡献率稍低,为29.4%。  相似文献   

14.
In the technological processes of ore flotation in the non-ferrous metal industry flotation, tailings constitute up to 98% of the total of the processed material. They are stored in sedimentation ponds as fine-grained drift containing an excess of heavy metals, mainly zinc, cadmium, lead and copper. After the dehydration and drying up of the surface of sedimentation ponds, these metals are carried with dust by the wind and they are accumulated in the vicinity of the ponds in humus horizons of soils causing considerable degradation and even devastation. In this publication, we have presented the results of research on the negative influence of such a structure on the soils of an adjacent fragment of forest and its dependence on the distance from the sedimentation pond. The level of degradation of the soils under research has been assessed on the basis of changes and transformations of the morphological soil profiles, the level of alkalization and accumulation of heavy metals (Zn, Pb, Cd) in the topsoil layers and their translocation in the soil horizons. The following soils have been distinguished in the investigated area: Haplic Podzols distorted and degraded as well as Urbic Anthrosols. The acquired results have served to depict the spatial accumulation of these heavy metals in the topsoil layers. The highest accumulation of heavy metals and the degradation of the forest sites connected with it has occurred in the vicinity of a sedimentation pond drain channel. Soil remediation has been recommended in this area.  相似文献   

15.
Composting of yard waste and sludge/yard waste mixtures was investigated during laboratory and field testing. A strong correlation between moisture content and windrow peak temperatures was observed. Odors were detected at cocomposting windrows when temperatures exceeded 54°C. The sludge to yard waste mixture ratio was found to affect resulting compost particle size and, consequently, oxygen transport. Compost quality was excellent, with pesticides below detection level and low concentrations of heavy metals.  相似文献   

16.
The present study investigated the impact of irrigation with wastewater on nutritional property and heavy‐metal concentrations in the soil and consequent accumulation in vegetables at sites having long‐term uses of wastewater for irrigation. Samples of irrigation water, soil, and root and shoot parts of palak plants were analyzed to determine the concentration of heavy metals. Wastewater irrigation led to increases in the total and phytoavailable heavy‐metal concentrations in the soil at all the sites. Heavy‐metal concentrations in soil under wastewater irrigation were negatively and positively correlated with soil hydrogen potential (pH) and organic carbon (OC), respectively. The enrichment factor and metal pollution index were higher at wastewater‐irrigated sites as compared to the clean water–irrigated ones. The study concludes that wastewater irrigation modified the physicochemical properties of the soil, leading to more availability of heavy metals in the soil and consequently to the plant.  相似文献   

17.
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...  相似文献   

18.
采用野外采样和室内分析相结合的方法,以典型农业区山东禹城的农田表层土壤(0-20 cm)为研究对象,分析了土壤中重金属Cr、Ni、Pb、As、Hg、Cd、Cu和Zn的含量,探讨了土壤中重金属的含量与不同人类活动的关系并进行了潜在生态风险评估。结果显示,8种重金属的含量均超过黄河下游潮土区的背景值。潜在生态风险评估表明,当地的农田土壤Cr、Ni、Pb、As、Cu、Zn有轻度的生态风险,Hg和Cd存在较大的生态风险。城市化进程、畜禽养殖和污灌是造成土壤Cd高生态风险的主要因素,城市化进程和污灌也是造成土壤Hg高生态风险的主要因素。禹城各区域土壤受8种重金属的综合潜在生态风险程度大小依次为城郊农田〉污灌农田〉典型施肥农田〉井灌农田〉引黄灌农田,不同人类活动区域土壤Cd生态风险和8种重金属的综合潜在生态风险存在显著差异。  相似文献   

19.
内蒙古草原白乃庙铜矿区土壤重金属污染特征研究   总被引:4,自引:0,他引:4  
对位于内蒙古荒漠草原上的白乃庙铜矿采选矿区土壤和尾矿区周围土壤重金属污染状况进行了调查研究。结果表明,矿区土壤中Cu、Cr、Ni、Fe和Mn浓度均高于内蒙古土壤平均值。单因子指数法评价结果表明,五个调查区域土壤都受到了重金属Cu、Cr、Ni、Mn、Fe的污染,其中Cu为重污染,Cr、Ni、Mn、Fe为轻污染,Pb为安全级别,Zn和As只对某些区域有轻污染。综合污染指数法评价结果表明,五个调查区域的土壤重金属污染等级均属重污染,主要贡献元素是Cu,其次是Cr、Ni、Mn、Fe,这与尾矿砂中这些重金属的浓度是相对应的。由于周边地形复杂,多为低山丘陵,所以该地区主导风向对于尾矿库区不同方向土壤重金属污染水平的影响差异并不显著。  相似文献   

20.
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   

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