上海滨岸带潮滩表层沉积物中重金属的空间分布与环境质量评价

１９９８年３月、７月、１０月,在对上海潮滩进行连续采样和观测的基础上,用原子吸收法测试了７０个沉积物中的Ｃｕ,Ｐｂ,Ｚｎ,Ｃｄ．Ｃｒ的含量。结果表明：（１）上海潮滩重金属含量有如下顺序：Ｚｎ〉Ｃｕ〉Ｃｒ〉Ｐｂ〉〉Ｃｄ。（２）从高潮滩到中低潮滩,重金属的含量递减。（３）不同的采样位置对重金属的含量有显著影响。（４）由于季节的变化,重金属元素的含量变化的幅度也很大,就现有三个季度数据对东海农场进行统计     

Benthic Community Structure and Sediment Properties in Barnegat Bay,New Jersey,Before and After Hurricane Sandy

Hurricane Sandy was an extraordinarily large storm that affected most of the eastern coast of the USA in October 2012. To assess this storm’s impact, the benthic invertebrate community structure and sediment properties were compared in samples collected 3.5 months prior to (July 2012) and 8 months after (July 2013) the hurricane at 97 locations in Barnegat Bay, New Jersey, USA. Barnegat Bay is a shallow back-barrier estuary just north of where Sandy made landfall. For all locations taken together, sediment total nitrogen concentration was lower afterwards, while total organic carbon and total phosphorus concentrations were similar. Sediment median particle size was the same before and after, but the sediment was better sorted after the storm. There were no differences in total abundance of invertebrates, species richness, species diversity, or the abundance of polychaetes, bivalves, or gastropods. Malacostracan crustaceans were more abundant after Sandy (average 82 (0.04 m²)^?1) than they were before (average 64), due almost entirely to increased abundance of ampeliscid amphipods, which showed a shift toward smaller sizes in 2013. Annelids in the order Clitellata were on average less abundant after the hurricane (17) than before (53). The apparent minimal effect of Sandy on the benthic community in Barnegat Bay was probably because the passage of the hurricane had no detectable effects on salinity or dissolved oxygen concentrations throughout the bay.     

Substrate characteristics associated with the distribution of the ribbed mussel,Geukensia demissa (Modiolus demissus), on a tidal creek bank in Southern New Jersey

The substrate composition is directly associated with the distribution of the Ribbed Mussel Geukensia demissa (=Modiolus demissus) along tidal-creek banks. Mussels were counted within a 2 dm × 5 dm microplot frame, and soil samples were collected at 5 m intervals for 320 m along Big Sheepshead Creek, near Tuckerton, New Jersey. Organic decomposition, percentage organic matter, and percentages of sand, silt, and clay were determined for each soil sample. Mussels were most frequently found in substrates characterized by low organic decomposition (Von Post >5), high organic matter content, (10–20%), and low sand content (0–20%).     

南通近海潮滩表层沉积物重金属含量特征与生态风险评价

基于南通近海(洋口港—吕四)潮滩特点布设潮滩断面并采集表层沉积物,根据样品汞、镉、铅、砷、铬等7种重金属元素含量测试结果,分析研究区沿海潮滩表层沉积物主要重金属元素含量特征,并与江苏其他滨岸地区潮滩沉积物的重金属含量进行对比,初步探讨2009—2012年南通沿海滩涂表层沉积物重金属含量变化与元素的相关性。采用潜在生态危害指数法评价南通近海潮滩表层沉积物中7种重金属元素的潜在生态危害系数及潜在生态风险。南通潮滩表层沉积物重金属含量分布均匀,且低于江苏省苏北其他地区沿海潮滩的沉积物含量。7种重金属元素的相关分析表明,Cu与Pb、Zn具有较好的相关性,Pb与Cd、Hg的相关性最差。潜在生态危害指数法评价表明,南通近岸潮滩表层沉积物7种重金属潜在生态危害系数均属低生态危害范畴,近岸海域(洋口港—吕四段)潮滩表层沉积物环境质量总体较好。     

云蒙湖表层沉积物重金属分布特征及风险评价

为了解云蒙湖表层沉积物中重金属的污染状况,选取云蒙湖沉积物中6种重金属(Cu、Zn、Pb、Cr、Cd、As)作为研究对象,测定并分析其在云蒙湖表层沉积物中的分布、来源及生态风险,以期为云蒙湖沉积物中重金属污染治理及饮用水安全保障提供依据。采用富集系数法、相关性分析及聚类分析对重金属来源进行分析,并选用富集系数法、地累积指数法和潜在生态危害指数法对重金属污染程度及潜在生态危害进行了评价。结果表明:云蒙湖表层沉积物中6种重金属Cu、Zn、Pb、Cr、Cd、As平均含量分别为20.9、73.1、23.1、62.0、0.4和4.5 mg/kg;与临沂市土壤背景比较,Cd、Zn和Cr的含量超过临沂市土壤背景值,Cd污染最严重。重金属来源分析结果显示:Cd受人类活动影响较大,可能与区域农业和林业施肥有关;Cu、Zn、Pb、Cr和 As这几种重金属以自然来源为主。综合富集系数法、地累积指数法和潜在生态危害指数法3种评价方法的结果得出,云蒙湖表层沉积物中Cd 为最主要的污染元素,且具有较强的生态危害。     

Concentration distribution and assessment of several heavy metals in sediments of west-four Pearl River Estuary

Grain size parameters, trace metals (Co, Cu, Ni, Pb, Cr, Zn, Ba, Zr and Sr) and total organic matter (TOM) of 38 surficial sediments and a sediment core of west-four Pearl River Estuary region were analyzed. The spacial distribution and the transportation procession of the chemical element in surficial sediments were studied mainly. Multivariate statistics are used to analyses the interrelationship of metal elements, TOM and the grain size parameters. The results demonstrated that terrigenous sediment taken by the rivers are main sources of the trace metal elements and TOM, and the lithology of parent material is a dominating factor controlling the trace metal composition in the surficial sediment. In addition, the hydrodynamic condition and landform are the dominating factors controlling the large-scale distribution, while the anthropogenic input in the coastal area alters the regional distribution of heavy metal elements Co, Cu, Ni, Pb, Cr and Zn. The enrichment factor (EF) analysis was used for the differentiation of the metal source between anthropogenic and naturally occurring, and for the assessment of the anthropogenic influence, the deeper layer content of heavy metals were calculated as the background values and Zr was chosen as the reference element for Co, Cu, Ni, Pb, Cr and Zn. The result indicate prevalent enrichment of Co, Cu, Ni, Pb and Cr, and the contamination of Pb is most obvious, further more, the peculiar high EF value sites of Zn and Pb probably suggest point source input.     

渤海湾西部海域表层沉积物重金属含量分布与评价

通过分析测定渤海湾100个站位表层沉积物中重金属元素的含量,探讨其分布特征及富集状况,并通过地累积指数法和潜在生态危害指数法对渤海湾西部岐口凹陷海域底质环境进行了评价。结果表明：渤海湾西部海域表层沉积物中As、Hg、Cu、Pb、Cd的平均含量分别为12．9×10－6、0．031×10－6、29．5×10－6、27．4×10－6、0．159×10－6。结合5种元素的地球化学图及地累积指数法分析表明,研究区表层沉积物整体上未受到As、Hg、Cu、Pb、Cd的污染,而在高值区Pb和Cu达到轻度污染的水平;潜在生态危害指数法的评价结果指明,重金属元素的潜在危害程度顺序是Hg＞Cd＞As＞Pb＞Cu,研究区重金属的潜在生态危害轻微,只有在高值区,Hg和Cd才达到中等程度的生态危害。     

湖泊沉积物中重金属的环境地球化学

概要地回顾了近年来国内外湖泊沉积物中重金属环境污染方面的研究成果,介绍了湖相沉积物重金属研究的主要内容、方法和可能的发展方向.认为就重金属成因方面应加强区分其主要来源是岩石和矿物风化的碎屑产物、大气降尘、人类活动等的研究;重金属污染方面更应重视污染物质的生物有效性、迁移转化机理和重金属"二次污染"的研究;研究手段上,注重运用同位素示踪与定年技术来研究重金属的来源和污染历史,应用高分辨率沉积物钻心研究环境的变迁.最后提出加强多学科的综合研究,建立中国湖泊基准数据库,为探讨湖泊湿地的可持续发展提供依据.     

Assessment of organic pollutants in coastal sediments, UAE

Twenty-five stations were selected along the UAE coastal region to delineate the distribution and to determine the source of total petroleum hydrocarbon (TPH), total organic carbon (TOC), total Kjeldhal nitrogen (TKN), polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs). The concentrations of TPH ranged between 46 and 223 mg/kg and the level of TOC was in the range from 0.044 to 17.8 wt%, while TPAHs occupied the range of 5–102.2 μg/kg. On the other hand, TPCBs showed values between 60 and 205 μg/kg and TKN ranged from 104 to 1,073 mg/kg. The present study shows that the distribution of organic compounds in UAE sediments were within safe limits comparing with previous studies. The present study revealed that TOC can be used as an indicator of oil pollution in heavily oiled sediments. The highest values of TOC, TPH, TPAHs and TPCBs related to the stations covered in fine sand due to adsorption properties and the large surface areas of the grains. The evaporation of low-boiling point compounds from surface layers leads to the enrichment of sediments with a thick residual. Al Sharjah-1 exhibited the highest values of TPH and TOC at Ras Al-Khaima-5, Umm Al-Quwen-1 and Dubai-1, while the highest values of TPAHs were at KhorFakkan-9, the highest value of TPCBs was at Ajman-2, and the highest values of TKN were at KhorFakkan-1, KhorFakkan-6 and Dubai-1.     

Origin and chemical partitioning of heavy metals in riverbed sediments

In the present investigation, bulk and chemical partitioning of elements in the Shefa-Rud riverbed sediments are studies. Higher concentrations of elemental concentrations have been observed in estuarine zone when compared with riverine sediments (except for AI, Fe, Pb and Mn). Manganese is mobilized under anoxic conditions prevailing in the Caspian Sea. Lithogenous materials are greatly diluted in the estuarine zone by various pollutants present in the Caspian Sea. Organic metallic bonds are not significantly present in the area of study. Geological units of the area of study have resulted in the lower concentrations of elemental concentrations of riverbed sediments when compared with published values for mean crust and world sediments ones. Though, cluster analysis has clearly shown the importance of alumina-silicates in controlling the distribution of Fe and Mn in riverbed sediments but it could not depict controlling mechanism for other studied elements. Geochemical Index (Igeo) and Enrichment Factor (EF) values are indicative of a clean environment throughout the river course. These values are in a well agreement with results of chemical partitioning data. Quantification of EF values is not logically possible and therefore Igeo values can be used more effectively.     

Accumulation and partitioning of heavy metals in mangrove rhizosphere sediments

A field study was conducted to clarify the effect of rhizosphere processes on the accumulation and partitioning of heavy metals (Pb, Zn, Cu, Cr, Cd and Ni) in mangrove sediments. Metals were fractionated by a sequential extraction procedure into three chemically distinct fractions: water soluble, exchangeable and carbonate bound (B1), Fe–Mn oxide bound (B2), and organic and sulfide bound (B3). Results indicate that rhizosphere processes tend to increase the metal concentrations in the rhizosphere sediments. However, plant uptake may result in the decrease of the metal concentrations in the rhizosphere sediments when the metal concentrations are relatively low in the bulk sediments. Compared with the bulk sediments, the rhizosphere sediments have low concentrations of heavy metals in the B1 and B2 fractions and high concentrations in the B3 fraction. Either an increase or decrease in the residual fraction of heavy metals in the rhizosphere sediments may appear, depending on whether the formation of the refractory metal-organic compounds or the activation of the residual fractions dominates. Results also indicate that mangrove plants absorb and store non-essential metals in the perennial tissues, thus reducing the export of non-essential metals via leaf litter transport. Mangrove plants are excellent candidates for phytostabilization of heavy metals in intertidal substrates.     

广西茅尾海入海河口表层沉积物重金属分布及风险评价

为揭示茅尾海入海河口表层沉积物中重金属分布特征及生态风险,在茅岭江、大榄江、钦江入海河口采集13件表层沉积物样品进行重金属分析。研究结果表明,茅尾海沉积物中重金属As、Cd、Cr、Cu、Hg、Pb、Zn含量平均值分别为7.78×10-6、0.14×10-6、37.6×10-6、18.9×10-6、0.004 8×10-6、22.5×10-6、54.7×10-6,均低于GB 18668—2002的一类标准。沉积物中重金属空间分布差异较大,茅尾海东部工业区和西部茅岭江附近具有较高的重金属含量。重金属污染分析表明,大部分重金属元素显示为无污染—轻度污染水平,Cr具有中等污染水平;生态风险分析显示,重金属总体处于较低潜在风险,东部工业区Hg、Cd显示出中等生态风险。通过相关性分析、聚类分析、主成分分析探讨重金属污染物来源,结果显示重金属污染主要受河流控制,Hg、As、Cd还受到临港工业区废水排放的影响。综合研究表明,茅尾海生态环境总体较好,但建议重点关注东部工业区重金属排污状况。     

Partitioning of heavy metals in surface Black Sea sediments

Bulk heavy metal (Fe, Mn, Co, Cr, Ni, Cu, Zn and Pb) distributions and their chemical partitioning, together with TOC and carbonate data, were studied in oxic to anoxic surface sediments (0–2 cm) obtained at 18 stations throughout the Black Sea. TOC and carbonate contents, and available hydrographic data, indicate biogenic organic matter produced in shallower waters is transported and buried in the deeper waters of the Black Sea. Bulk metal concentrations measured in the sediments can be related to their geochemical cycles and the geology of the surrounding Black Sea region. Somewhat high Cr and Ni contents in the sediments are interpreted to reflect, in part, the weathering of basic-ultrabasic rocks on the Turkish mainland. Maximum carbonate-free levels of Mn (4347 ppm), Ni (355 ppm) and Co (64 ppm) obtained for sediment from the shallow-water station (102 m) probably result from redox cycling at the socalled ‘Mn pump zone’ where scavenging-precipitation processes of Mn prevail. Chemical partitioning of the heavy metals revealed that Cu, Cr and Fe seem to be significantly bound to the detrital phases whereas carbonate phases tend to hold considerable amounts of Mn and Pb. The sequential extraction procedures used in this study also show that the metals Fe, Co, Ni, Cu, Zn and Pb associated with the ‘oxidizable phases’ are in far greater concentrations than the occurrences of these metals with detrital and carbonate phases. These results are in good agreement with the recent studies on suspended matter and thermodynamic calculations which have revealed that organic compounds and sulfides are the major metal carriers in the anoxic Black Sea basin, whereas Fe-Mn oxyhydroxides can also be important phases of other metals, especially at oxic sites. This study shows that, if used with a suitable combination of the various sequential extraction techniques, metal partitioning can provide important information on the varying geological sources and modes of occurrence and distribution of heavy metals in sediments, as well as, on the physical and chemical conditions prevailing in an anoxic marine environment.     

Correlation between magnetic susceptibility and distribution of heavy metals in contaminated sea-floor sediments of Hong Kong Harbour

 Magnetic susceptibility measurements were conducted on 24 vibrocores obtained from an area located off the northeastern coast of Lantau Island in Hong Kong. High intensities of magnetic susceptibility were detected in the uppermost sections of the majority of the cores. Several magnetic parameters measured for one of the cores suggest that the variations in the magnetic characteristics over depth are mainly due to varying concentrations of the magnetic minerals. Since a strong correlation has been found between magnetic susceptibility and the heavy metals Pb, Cu, Zn and Cr, an anthropogenic contamination origin is thought to be the cause. The present study shows that magnetic susceptibility is a fast, inexpensive and non-destructive method for the detection and mapping of contaminated sediments. Received: 12 August 1997 · Accepted: 18 November 1997     

Spatial distribution and assemblage structure of macrobenthos in a tidal creek in relation to industrial activities

The impact of petrochemical special economic zone activities on the health status of Jafari Creek was studied by assessing the changes in macroinvertebrate assemblages in nine sites during September 2006–January 2008. The relationship between spatial pattern of macroinvertebrate assemblages and ambient factors (i.e. water temperature, salinity, pH, dissolved oxygen, sediment grain size distribution, sediment organic content, heavy metals contents) was measured. Background enrichment indices, contamination factor and contamination degree, were used to assess the health status in the study area based on nickel, lead, cadmium and mercury contents of the sediments. The macrobenthic communities had a low diversity and were dominated by opportunistic taxa. The BIO-ENV analysis identified salinity, dissolved oxygen, pH and silt/clay content of sediments as the major environmental variables influencing the infaunal pattern. This suggests that management should attempt to ensure minimal disturbance to environmental variables underlying the spatial variation in macroinvertebrate assemblages. Background enrichment indices showed that the health of Jafari Creek has declined over time due to the constant discharge of heavy metals to the Creek system. These indices also identified a significant degree of pollution in the study area. The decrease in the ecological potential of Jafari Creek was best highlighted by the alteration in macrobenthic assemblages.     

洞庭湖沉积物重金属环境地球化学

对洞庭湖沉积物样进行了Cu、Pb、Zn、Cd、Cr、Ni、As和Hg等8种元素含量分析.结果显示,洞庭湖沉积物中重金属污染物主要是Cd和Hg,其次是Pb、Zn、As和Cu;Cd平均含量达到2.7mg/kg,是国家土壤环境质量三级标准(1.0mg/kg)的近3倍;Cu、Pb、Zn、As和Hg平均含量分别为51.3mg/kg、52.8mg/kg、140mg/kg、22.5mg/kg和0.22mg/kg,均超过国家土壤环境质量一级标准.运用地累积指数法对其污染程度进行了评价,认为重金属污染最严重的湖区是东洞庭湖的鹿角至城陵矶湖区(段),污染物可能主要来源于湘江流域;各子湖区(段)重金属综合污染状况评价结果是:东洞庭湖＞大通湖＞横岭湖＞万子湖＞西洞庭湖＞采桑湖.入湖各河口区沉积物重金属含量与历史资料的对比表明,8种重金属含量均有较高程度的富集,反映近年来洞庭湖流域内重金属污染有增加的趋势.     

Heavy metals distribution in the sediments of ganges and Brahmaputra rivers

Bed sediments were collected from the entire region of the Ganges basin and some parts of the Brahmaputra. In addition, selected stations were sampled for suspended sediments as well. The samples were analysed for a number of heavy metals (Fe, Mn, Ni, Cr, Cu, and Zn) by the thin-film energy dispersive X-ray fluorescence technique. There are pronounced temporal and spatial variations in the heavy metals distributions. Suspended sediments are 5–10 times richer than the bed sediments. None of the tributaries contribute significant heavy metal load, but around urban areas in Yamuna (tributary of Ganges), very high levels due to the distribution from the drainage network are observed. Compared to the Brahmaputra, the distribution and fractionation of heavy metals in the Ganges sediments are more erratic and highly variable. All the metals considered show high correlation among themselves. Given the high flux of suspended sediments from the Himalayan rivers (nearly 20% of the global flux), the worldwide budget for heavy metal transport may need to be suitably revised.     

海河流域沉积物重金属形态分布特征及生态风险评估

海河流域中含有重金属的生活、工业污水排入量较大,致使重金属大量进入水环境并聚集在沉积物中。传统的生态风险评估方法忽略了重金属形态分布特征因素,造成生态风险评估可靠性较低的问题。本文以海河流域平原段河流为研究对象,提出了海河流域沉积物重金属形态分布特征及生态风险评估研究,在海河流域设置采集点,采集沉积物样品,并在实验室中使用混合酸处理样品,采用原子吸收法测定样品中重金属含量,分析沉积物重金属形态分布特征。在生态风险评估中,借助丰度计算完善生态风险评估指数,设计重金属生态风险评估标准。实验结果表明,设计方法得到的各个采样点和各类重金属评价与实际情况更加接近,可靠性更高,评估性能更好。