Influences of hydrological regime on heavy metal and saltion concentrations in intertidal sediment from Chongming Dongtan,Changjiang River estuary,China

The tidal flat along the Changjiang(Yangtze) River estuary has long been reclaimed for the agricultural purposes, with the prevailing hydrological conditions during such pedogenic transformations being of great importance to their successful development. In this study, samples of surface sediment from Chongming Dongtan, situated at the mouth of the Changjiang River estuary, were collected and analyzed in order to understand how hydrological management can influence the concentrations of heavy metals and salt ions in pore water, and chemical fractionation of heavy metals during the reclamation process. We performed a series of experiments that simulated three dif ferent hydrological regimes: permanent flooding(R1), alternative five-day periods of wetting and drying(R2), continuous field capacity(R3). Our results exhibited good Pearson correlations coefficients between heavy metals and salt ions in the pore water for both R1 and R2. In particular, the concentrations of salt ions in the pore water decreased in all three regimes, but showed the biggest decline in R2. With this R2 experiment, the periodic concentration patterns in the pore water varied for Fe and Mn, but not for Cr, Cu, Pb and Zn. Neither the fractionation of Ni nor the residual fractions of any metals changed significantly in any regime. In R1, the reducible fractions of heavy metals(Cr, Cu, Zn and Pb) in the sediment decreased, while the acid extractable fractions increased. In R2, the acid extractable and the reducible fractions of Cr, Cu, Zn and Pb both decreased, as did the oxidizable fraction of Cu. These data suggest that an alternating hydrological regime can reduce both salinity and the availability of heavy metals in sediments.     

Spatial Distribution and Risk Assessment of Heavy Metals in Paddy Soils of Yongshuyu Irrigation Area from Songhua River Basin,Northeast China

There is an increasing concern for potentially hazardous metals pollution, which can threaten crops production and human health. In this study, the spatial distribution and environmental risks of eight heavy metals in surface soil samples collected from the paddy fields in Yongshuyu irrigation area, Northeast China were investigated. The mean concentrations of Pb, Cr, Cu, Ni, Zn, Cd, Hg and As were 34.6 ± 4.67, 82.8 ± 9.51, 17.3 ± 4.09, 21.2 ± 12.0, 88.6 ± 17.9, 0.18 ± 0.15, 0.22 ± 0.07 and 8.77 ± 2.47 mg/kg, respectively, which were slightly higher than their corresponding background values of Jilin Province, indicating enrichment of these metals in the paddy soils, especially for Ni, Cd and Hg. The spatial distribution of heavy metals was closely correlated with local anthropogenic activities, such as agricultural production, mining and transportation. The hot-spot areas of As and Cd were mainly concentrated in the up-midstream where were associated with agricultural activities. Cr and Cu showed similar spatial distributions with hot-spot areas distributed the whole irrigation area uniformly. Ni was mainly distributed in the downstream where Ni quarries concentrated, while the spatial distribution patterns of Hg was mainly located in the upstream and downstream where the soil was significantly influenced by irrigation and coal mining emission. The spatial distributions of Pb and Zn were mainly concentrated along the highway side. The pollution levels of Yongshuyu irrigation area were estimated through index of geo-accumulation(Igeo), Nemerow integrated pollution index(NIPI) and potential ecological risk index(PERI). The results showed that Cd and Hg were the main pollutants in the study area. Health risk assessment results indicated that children were in higher non-carcinogenic and carcinogenic risks than adults with the carcinogenic metal of As. Ingestion was the main exposure pathway to non-carcinogenic and carcinogenic risk for both adults and children. Principal component analysis(PCA) indicated that Cr and Cu were mainly from parent materials, while Cd and As were mainly affected by agricultural activities. Pb and Zn were controlled by traffic activities, and the accumulations of Ni and Hg were associated with mining activities. This study would be valuable for preventing heavy metals inputs and safety in rice production of the Songhua river basin.     

农用地土壤中7种重金属可提取态的测定

该文以氯化钙溶液进行提取,采用电感耦合等离子体质谱法和原子荧光光谱法,测定农用地土壤中Cd,As,Pb,Cr,Cu,Zn,Ni等7种重金属可提取态,检出限在0.003~0.06 mg/kg之间。该方法用于4个可提取态质控样品的测定,测定值与推荐值基本相符,测定的相对标准偏差(n=8)在3.3%~9.1%之间。基于800余件农用地土壤样品的测定数据,对7种重金属可提取态与土壤pH值及重金属总量之间的关系进行了初步考察。结果表明,7个重金属可提取态和总量关系无明显相关性,仅在土壤酸性条件下可提取态Cd与总量Cd呈正相关性。7种重金属提取率大小顺序为Cd>Zn>Ni>Cu,As>Pb>Cr,其中Cd,Zn,Ni,Cu,Pb的提取率随土壤pH值的增大而迅速下降,而As,Cr在土壤碱性条件下的提取率略高于中酸性条件下的提取率。     

典型石漠化峰丛洼地土壤重金属的空间分异特征及其影响因素

研究石漠化峰丛洼地土壤重金属空间分异特征及其影响因素, 对推动区域土壤重金属污染防治、石漠化综合治理具有重要的指导意义和实践价值。以广西平果市典型石漠化峰丛洼地土壤为研究对象, 通过调查采样分析以及综合运用地统计学、地质累积指数、潜在生态危害指数和地理探测器等方法, 分析探讨土壤重金属的空间分异特征及其影响因素。结果表明, 研究区8种重金属元素的空间分布总体呈东北向西南降低的变化格局, 研究区东北部和东南部为重金属高值叠加区的集中分布区, Cr,Cd元素呈现中等的空间相关性, 其他6个重金属元素表现为强空间相关性;研究区受Cd,As,Cr,Cu,Zn等元素不同污染程度的影响, 且以Cd的影响尤为突出, 其地质累积指数和潜在生态危害指数分别高达1.34和107.73;pH、地层、Fe₂O₃、土地利用、P、CaO、Mn、到断层距离、石漠化程度是影响研究区土壤重金属空间分异的主要因子, 而且不同因子组对土壤重金属空间分异的交互作用以双因子增强型和非线性增强为主。因此认为不同因子对石漠化峰丛洼地土壤不同重金属元素空间分异特征的影响程度存在差异, Cd是石漠化峰丛洼地土壤污染程度和潜在生态危害程度最严重的重金属元素, 地层、Mn、CaO、岩性、到断层距离、P是影响Cd空间分异的关键因子。      

章丘区北部土壤重金属地球化学特征及潜在生态风险

以山东省济南市章丘区北部表层土壤中As等8种重金属元素为研究对象,利用多元统计进行重金属来源分析,采用污染负荷指数法及潜在生态危害指数法进行污染评价,结果表明:研究区表层土壤重金属元素含量低于济南市土壤背景值,Cd和Hg元素含量为强度变异,在表层土壤产生一定的富集;不同土地利用类型下重金属元素含量具有差异性。土壤中Cr,Cu,Ni和Zn来源于土壤母质,Cd和Pb元素来源于人类活动,As元素来源复杂。土壤综合污染以轻度污染为主,重金属元素污染程度大小为AsNiPbZnCrCuCdHg。综合潜在生态风险以轻微和中度为主,潜在生态风险强弱程度为HgCdAsCuPbNiCrZn,建议防范Hg和Cd元素污染及生态风险。     

舟山西蟹峙海洋倾倒区及邻近海域表层沉积物重金属污染及其生态风险评价

根据2011年7月浙江舟山西蟹峙海洋倾倒区及邻近海域表层沉积物重金属的监测结果,采用单因子指数法和Hakanson生态危害指数法分析表层沉积物重金属的污染特征,并评价其潜在生态风险。结果表明:沉积物重金属元素Cu、Zn、Pb、Cd、Cr、Hg、As含量均符合国家海洋沉积物质量一类标准;重金属元素污染程度由高到低依次为Zn、Cr、Pb、Cu、As、Cd、Hg,其中Cu、Pb、Cd、Hg和As 5种重金属元素为低污染水平,Zn和Cr 2种重金属元素为中等污染程度水平;7种重金属元素单个和综合潜在生态危害程度均为低风险水平,由高到低依次为Cd、Hg、As、Pb、Cu、Cr、Zn。     

煤矸石堆附近耕作层土壤中重金属污染状况与评价——以鲁西南煤炭基地为例

通过对鲁西南煤炭基地若干混堆的煤矸石山周围耕作层土壤的实际调查及分析测试资料,研究了煤矸石堆附近耕作层土壤中重金属污染状况。结果表明,土壤局部已经受到Cd、Ni的污染,但未出现多金属复合污染状况。煤矸石堆附近土壤已经受到采矿等人类活动的影响,其中Cd,Hg的人为影响最大。从8种重金属元素含量随深度的变化曲线形态来看,Hg,Cd 2种元素与Cr,Ni,Cu,Zn,Pb,As 6种元素曲线形态显示差异性,Hg,Cd元素在土壤中赋存、迁移等应具特殊性,有待进一步研究。     

Potential Effects of Episodic Deposition on Nutrients and Heavy Metals in Decomposing Litters of Suaeda glauca in Salt Marsh of the Yellow River Estuary,China

Episodic deposition has been recognized as a major factor affecting the decomposition rate of detrital material in salt marshes. In this paper, three one-off burial treatments, no burial treatment(0 cm, NBT), current burial treatment(10 cm, CBT) and strong burial treatment(20 cm, SBT), were designed in intertidal zone of the Yellow River Estuary to determine the potential influences of episodic deposition on nutrient(C, N) and heavy metal(Pb, Cr, Cu, Zn, Ni, Mn, Cd, V and Co) variations in decomposing litters of Suaeda glauca. Results showed that although various burial treatments showed no statistical difference in decomposition rate of S. glauca, the values generally followed the sequence of CBT(0.002 403/d) SBT(0.002 195/d) NBT(0.002 060/d). The nutrients and heavy metals in decomposing litters of the three burial treatments exhibited different variations except for N, Cu, Cr, Ni and Co. Except for Mn, no significant differences in C, N, Pb, Cr, Cu, Zn, Ni, V and Co concentrations occurred among the three treatments(P 0.05). With increasing burial depth, Cr and Cd levels generally increased while Cu, Ni and Mn concentrations decreased. Although episodic deposition was generally favorable for C and N release from S. glauca, its influence on release was insignificant. In the three burial treatments, Pb, Cr, Zn, Ni, Mn, V and Co stocks in S. glauca generally evidenced the export of metals from litter to environment, and, with increasing burial depth, the export amounts increased greatly. The S. glauca were particular efficient in binding Cd and releasing Pb, Cr, Zn, Ni, Mn, V and Co, and, with increasing burial depth, stocks of Cu in decomposing litters generally shifted from release to accumulation. The experiment indicated that the potential eco-toxic risk of Pb, Cr, Zn, Ni, Mn, V and Co exposure would be serious as the strong burial episodes occurred in S. glauca marsh.     

Seasonal and spatial distribution of trace metals in alpine soils of Eastern Tibetan Plateau,China

The distribution of trace metals in remote alpine region is an effective way to understand the impacts of regional human activity and vegetation on the alpine ecosystem. In this study, the concentrations of cadmium (Cd), copper (Cu), lead (Pb), and zinc (Zn) in the soils of Gongga Mountain, Eastern Tibetan Plateau, were investigated to reveal their seasonal and spatial distribution and enrichment state, and to decipher the effects of atmospheric deposition and vegetation on their distributions among five vegetation zones. The results showed that the concentrations of Cd, Pb, and Zn were higher in the O horizon than in other horizons despite the seasonal changes, whereas Cu was enriched in the C horizon. The enrichment states of the metals studied in the soils decreased in the order of Cd > Pb > Zn > Cu. Cd and Pb were mainly sourced from atmospheric deposition; Zn was from both atmospheric deposition and parent materials, whereas Cu was mainly from parent materials. Seasonally, the trace metals were generally higher in May and December but lower in September, implying the impact of vegetation on the distribution of trace metals under the plant uptake and the litter decomposition. Spatially, the higher enrichment of Cu, Pb, and Zn in the soils existed in the mixed broadleaf-coniferous forests and coniferous forests (approximately 3000 m above sea level). The results suggested that atmospheric deposition and biological processes are main factors controlling the seasonal and spatial distribution of trace metals in the soils of the remote alpine ecosystem.     

Heavy metal distribution in sediments of Muthupettai mangroves, south east coast of India

Core sediments from the Muthupettai mangroves on the southeast coast of India were analyzed for soil texture,total nitrogen,organic carbon,phosphorus and heavy metals(Fe,Mn,Cr,Cu,Ni,Pb,Zn and Cd).The distinct seasonal variation in the distribution of metals in the sediments was observed.The minimum concentration was recorded in river mouth and the maximum was in lagoon.High metal concentration in sediment was observed during monsoon and low concentration in summer.The total nu-trient in lagoon and river mouth was recorded in the range of 4.528 to 8.526 mg g-1 for organic carbon,2.213 to 10.5 mg g-1 for nitro-gen and 0.824 to 7.22 mg g-1.     

Spatial distribution,sources and ecological risk assessment of heavy metals in Shenjia River watershed of the Three Gorges Reservoir Area

Surface soil/sediment samples were collected from the Water-Level Fluctuation Zone (WLFZ), cultivated land and forest land at 50 different grid points from Shenjia watershed, the Three Gorges Reservoir area in August 2013. The spatial distribution, sources and ecological risk assessment for Arsenic (As), Cadmium (Cd), Chromium (Cr), Copper (Cu), Nickel (Ni), Lead (Pb) and Zinc (Zn) were analyzed in this study. The results showed all tested metals had similar distribution patterns except Ni and Cr, with areas of high concentrations distributed in the southwest (WLFZ and watershed outlet) of the study area. Ni and Cr, which were highly positively correlated and present in high concentrations, were primarily distributed in the south and middle zones of the study area. Lower concentration areas of all metals were uniformly distributed west of the high-elevation zones and forest land. Factor analysis (FA) and factor analysis-multiple linear regression (FA-MLR) showed that the major sources of Cd were fertilizer and traffic sources, which together accounted for 87% of Cd. As, Zn and Cu levels were primarily supplied by industrial and domestic sources, accounting for 76% of As, 75% of Cu and 67% of Zn. Surface soils/sediments of the study watershed contaminated by Cd represent a high ecological risk, whereas other metals represent low ecological risks. The potential ecological risk index (PERI) analysis indicated that it had a low (wide-range) ecological risk and a moderate (small-range) ecological risk primarily distributed in the outlet of the study watershed. Fertilizers and traffic are the primary sources of Cd pollution, which should be more closely controlled for the purposes of water quality and ecological conservation.     

山东烟台南部海岸带地区土壤重金属来源、空间分布及潜在风险评价

海岸带处于陆地和海洋的接合部,人类开发活动密集,环境影响因素日趋复杂。选取烟台南部海岸带为研究对象,系统采集686个表层土壤样品对As,Cd,Cr,Cu,Hg,Ni,Pb,Zn共8个重金属元素含量进行测量,采用多元统计法及地统计法分析了8个重金属元素的来源及分布特征。最后对烟台南部海岸带地区进行了潜在生态风险评价。研究结果表明烟台南部海岸带地区整体污染程度较轻,所有重金属元素含量平均值均未超过国家二级标准。其中Cr,Ni,Cu元素主要来源于成土母质;As,Pb为混合源;Cd,Zn主要来自于工业三废、农业生产。研究区整体处于中低生态风险水平,Cd,Hg元素高生态风险点数量较多,需优先治理。     

柞水银铅矿地表径流沉积物中污染物相态分析

采自柞水银铅矿地表径流６个沉积物样品,用连续提取法提取了金属元素的５种化学相态（可交换相、碳酸盐相,铁锰氧化物结合相,有机质－硫化物结合相及残渣相）,测定了各相中铜铅锌含量,分析了其分布特征。结果表明,在河流沉积物中,铜主要以残渣相和有机质相存在,铅、锌主要为铁锰水合氧化物相和碳酸盐相。在此基础上,对矿山开采中环境影响进行了讨论。     

Mineral constituents in common chanterelles and soils collected from a high mountain and lowland sites in Poland

This paper reported the results of the determination of Ag, Al, Ba, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, P, Pb, Rb, Sr and Zn in Common Chanterelles (Cantharellus cibarius) Fr. and surface soil layer (0-10 cm) underneath the fruiting bodies. Mushrooms and soils were collected from a lowland site in the Hel Peninsula (Baltic Sea coast) and a high mountain site in the Tatra Mountains. The trace elements were determined using validated method and inductively coupled plasma - atomic emission spectroscopy (ICP-AES). Common Chanterelles that emerged at sites poor in mineral nutrients podzols of the Hel Peninsula forests efficiently bioconcentrated several essential trace elements (K, P, Co, Cu, Mn, Na, Zn), while the abundance of those elements in carpophores was around half less compared to specimens from Zakopane region and which emerged in soils much richer in minerals. Common Chanterelles collected at two spatially distant background areas in Poland were only weakly contaminated with metals such as Ag, Cd, Hg and Pb. The maximum tolerable Cd and Pb contents of certain cultivated mushrooms are regulated in the European Union by law and these hazardous metals in C. cibarius were far below tolerance limits set.     

滨州海岸带土壤和海底沉积物重金属空间分布特征

通过对滨州近海海域海底沉积物测试数据及海岸带陆域土壤地球化学分析,对滨州海岸带陆域土壤和海底沉积物中7种重金属(Hg,Cd,Pb,Cu,Zn,Cr,Ni)的空间分布特征进行了研究,并绘制了各指标含量陆海联合分区图。分析结果表明,滨州市海岸带重金属元素含量基本上均低于国标规定的海洋一类沉积物的最高标准,仅有个别元素含量超过一级标准值,表明局部存在一定的重金属污染。从滨州海岸带重金属含量空间分布上来看,除Hg元素外,其余重金属元素含量呈现一定的规律,基本上陆域含量高于海域含量,且大部分元素都呈现出陆域城镇值高,郊区值低的态势。区内化工企业较发达,Ni,Cr属于中度变异区,Cd,Hg,Pb属于高度变异,受人为影响因素较大,考虑区内土壤及海底沉积物重金属富集主要来源于工业"三废"。     

武汉市东西湖区主要湖泊表层沉积物重金属污染特征与生态风险评价

人类活动对水环境影响巨大,同时水环境影响着人类的生产生活。采用地质累积指数法及潜在生态危害指数法对武汉市东西湖区主要湖泊表层沉积物重金属情况展开评价发现东西湖主要湖泊表层沉积物平均污染程度处于相对较低水平。地累积指数法评价结果表明,东大湖和金湖中Cd元素处于中度污染水平累积,墨水湖和上金湖中Cd元素为偏中度污染累积水平,其他湖泊沉积物中重金属均处于轻度或无污染水平。潜在生态危害指数法评价结果表明金湖和东大湖沉积物中重金属的潜在风险处于重度生态风险水平,墨水湖、上金湖、下银湖处于中度风险水平,其余湖泊沉积物中重金属的潜在风险均处于低风险水平。主成分分析表明,Hg、Cr、Ni、Cu、Zn、Cd、Pb可能来自于工业和交通源的排放,而As可能与农药的使用有关。后期金湖、东大湖、墨水湖、上金湖和下银湖的内源污染治理过程中需考虑重金属的生态风险问题。      

Spatial Variation and Risk Assessment of Arsenic and Heavy Metals in Surface Water and Suspended Particulate Matter in Tail Reaches of the Yellow River,China

To determine the pollution levels and potential toxic risks of arsenic(As) and heavy metals(Cr, Ni, Cu, Zn, Pb and Cd) in water and suspended particulate matter(SPM) in tail reaches(including freshwater reach and low-salinity reach) of the Yellow River as the Flow-Sediment Regulation Project(FSRP) has been carried out for approximately 15 yr, the surface water and SPM were sampled at pre-flood(April) and post-flood seasons(October). Results showed that similar changes of As and metal levels in water and SPM were observed along the tail reaches at pre-flood or post-flood season. Compared to pre-flood season, the levels of As, Cu, Cr and Ni in freshwater reach and the concentrations of Cr and Ni in low-salinity reach rose greatly at post-flood season. The levels of As and metals in SPM of freshwater reach or low-salinity reach at pre-flood season were significantly higher than those at post-flood season(P < 0.01).The pollutions of As and metals in surface water of tail reaches at pre-flood or post-flood season were not serious. The SPM in freshwater reach at pre-flood season were polluted by Cd, As, Cr, Cu and Ni while those in low-salinity reach were polluted by Cd and Cr. The SPM in freshwater reach at post-flood season were polluted by Cd and Pb while those in low-salinity reach were polluted by Cd and Cr.Cd was identified as heavy metal of primary concern at both pre-flood and post-flood seasons. Combined with the existed data reported in present research, this study found that the toxic risk of As and metals in SPM of tail reaches at pre-flood season was higher than that at post-flood season, implying that the implementation of FSRP during flooding season, to a great extent, reduced the toxic risk of these elements. With the long-term implementation of FSRP, the pollution levels of As and metals(particularly for Cd) in SPM of tail reaches might be elevated and the potential toxic risk primarily produced by Cr, Ni and As might be increased if effective measures were not taken in future.     

湛江港附近海域潮间带海水、沉积物和贝类体内的重金属

于2005年8月对湛江港附近海域潮间带的海水、表层沉积物和贝类体内的重金属进行了分析,结果表明:海水中的砷优于海水水质Ⅰ类标准,而汞、铜、锌、铅、镉均有不同程度的污染,其中铜、铅、镉污染较为严重,均劣于海水水质Ⅳ类标准;表层沉积物中砷的含量低于全国海岸带背景值,而汞、铜、锌、铅、镉均高于全国海岸带背景值,其标准指数分别为1.35、1.66、1.50、2.08、3.10,汞、铜略高于海洋沉积物质量标准第一类标准,有轻微污染,砷、锌、铅均低于海洋沉积物质量标准第一类标准,未受污染,而镉略高于海洋沉积物质量标准第二类标准,环境受镉污染。各元素在各站点的分布没有规律性。牡蛎和蛤仔体内各重金属含量均优于海洋生物污染评价标准和人体消费卫生标准,其卫生质量良好。     

Spatial distribution and changes of heavy metals of agricultural lands in typical pregrading coast in Dongtai City,Jiangsu Province,China

According to the historical changes of coastal lines, seven soil sampling districts, from land to sea, were arranged in Dongtai City, Jiangsu Province to sample soils from surface and profile. Concentrations of seven major heavy metals （HMs）, granularity, pH, organic matters and C/N of the soil samples were analyzed. Results show that concentrations of heavy metals in agricultural land present a certain spatial variance, decreasing from land to sea. Pollution assessment indicates that the agricultural soils were not polluted by HMs, but the potential pollution of Cu and Hg needs to be alerted. Different HMs accumulate in the surface and sub-surface of the soil profiles, and concentrations of Hg and Pb decrease significantly with the increment of soil depth. Concentrations of HMs exhibit a significantly negative correlation to pH, but have no significant relation with organic matters in soil. Principle component analysis show that the concentrations of HMs relate to the land use history. Concentrations of Hg, Ni and Cr in soil are closely related with land use history, and concentrations of Pb, Cu and Cr are affected by land use history as well as other factors. However, there is no significant relation between concentration of As and land use history.     

Geochemical characteristics of heavy metals in riparian sediment pore water of Songhua River,Northeast China

This study reports the geochemical characteristics of zinc (Zn), copper (Cu), lead (Pb), nickel (Ni), mercury (Hg), iron (Fe), and manganese (Mn) in the riparian sediment pore water of the Songhua River, Northeast China. In total, 36 pore water samples and 18 surface water samples from three typical sections were collected and analyzed in June 2009. Cluster analysis of heavy metals was performed to analyze the pollution sources of the metals. Results showed that Hg concentrations in the pore water were greater than those in the surface water, indicating a potential ability of Hg release from riparian sediment system to river water. However, concentrations of Fe and Mn in the surface water were greater than those in the pore water, demonstrating that the microenvironments of riparian and riverbed sediment systems were quite different. Variations of Zn, Cu, Pb and Ni between the surface and the pore water were different in each section. Most metals had similar horizontal and profile distribution characteristics in the three sections except for Zn and Ni. Hg, Fe and Mn concentrations in the pore water increased gradually with the increase in horizontal distance from water body, in contrast to this, Cu decreased, and Pb presented a fluctuating trend. With the increase in depth, Pb and Fe, Cu and Mn showed the same trends, and Hg showed a variable trend. The above distribution characteristics could mainly be attributed to the properties and the interactions of metals, pH and oxidation-reduction conditions, and the complex pollution sources and hydrologic regime in history. The probable sources of metals include the historical and ongoing discharge of industrial wastewater, mining activities, sewage irrigation for agricultural production, and atmospheric deposition from coal-fired plants.