洞庭湖表层沉积物营养物质污染特征与生态风险评价

为揭示洞庭湖表层沉积物营养物质的空间分布特征与生态风险, 分别于2012 年2 月和2013 年4 月采集了该湖具有代表性的9 个点位的表层沉积物, 测定了其OM、TN 和TP 的含量, 分析了营养物质的空间分布特征, 并采用沉积物质量基准法对其潜在生态风险进行了评价。结果表明, 洞庭湖表层沉积物中OM 含量在1.48%-4.22%之间, 平均值为2.06%, TN 含量在382-2217 mg·kg–1 之间, 平均值为1340 mg·kg–1, TP 含量在142-716 mg·kg–1 之间, 平均值为294 mg·kg–1, 与国内其它湖泊(水库)相比, 洞庭湖表层沉积物中OM 和TN 含量处于中等水平, 其内源负荷不容忽视;OM 和TN 含量的空间分布相似, 总体表现为南洞庭湖区>东洞庭湖区>西洞庭湖区, TP 含量总体表现为东洞庭湖区>西洞庭湖区>南洞庭湖区; 初步评价结果表明, 洞庭湖表层沉积物营养物质存在较低程度的生态风险, 主要来自TN 和OM。     

不同起源秋茄林湿地沉积物重金属污染与健康风险评价

秋茄(Kandelia obovata)林生态系统的重金属污染是滨海湿地研究的重要组成.为探究闽东不同起源秋茄林湿地的健康风险与重金属污染的状况,运用污染负荷指数法和人体健康风险评价法分析闽东不同起源秋茄林湿地表层沉积物重金属的含量特征并评估其健康风险.结果表明:(1)秋茄天然林湿地表层沉积物重金属平均含量排序为Zn(...     

鸭绿江口湿地滩涂表层沉积物重金属空间分布特征及生态风险评价

利用GIS软件空间内插值法分析鸭绿江河口近海湿地滩涂表层沉积物重金属的空间分布特征,并采用环境风险指数法和潜在生态危害指数法进行重金属元素的生态风险评价.结果表明: 研究区表层沉积物中的重金属含量与国内典型河口湿地相比处于较高水平.从空间分布上看,重金属含量东部高于西部,在人类活动密集区存在明显的累积性.环境风险指数法分析结果表明,Cu对该区域环境污染的影响最大,而Hakanson潜在生态危害指数法分析结果表明,Hg和Cd的潜在生态危害最大,重金属的综合潜在生态危害指数介于93.65～507.20,平均值为189.30,属于中等生态危害,并以东部潜在危害程度最大,应作为今后重金属污染防治的重点区域.     

贵州阿哈水库不同季节水体和沉积物重金属分布特征及污染评价

探讨湖库不同季节水体和沉积物中重金属的分布特征并对其进行污染评价,有助于深入理解湖库环境重金属污染的时空动态演化及其环境效应.对贵州阿哈水库不同季节水体和沉积物中8种重金属的深度分布特征及其污染评价进行了分析.阿哈水库水体重金属含量排序为Ni＞As＞Zn＞Cu＞Cr＞Co＞Pb＞Cd.夏秋季节缺氧的底层水体重金属含量增...     

赣江上游沉积物重金属空间分布及污染特征

为了解赣江上游表层沉积物重金属污染特征,采集赣江上游38个样品,采用电感耦合等离子体质谱仪(ICP-MS,Agilent 8800)分析沉积物中重金属含量,结合内梅罗综合污染指数法、地累积指数法、主成分分析及沉积物质量基准等研究赣江上游沉积物中重金属污染程度,分析污染物可能的来源及评价其存在的生态风险。结果表明:赣江上游沉积物中W、Cr、Mn、Cu、Zn、As、Cd、Hg、Pb等9种重金属的平均含量分别为12.30、4.40、999.84、9.72、293.81、47.66、2.85、1.34、63.68 mg·kg-1;除Cr和Cu外,其余7种重金属的平均值均超过江西省土壤背景值。内梅罗综合污染评价表明,赣江上游表层沉积物中47.37%的采样点呈严重污染,28.95%采样点污染明显,其中污染程度章水段>桃江段>贡江段;地积累指数法显示,Mn、As、W、Pb呈轻度污染,Cd和Hg呈中度或偏重度污染;主成分分析显示,As、W、Hg、Pb具有相似的污染源,Cr和Mn具有相似的污染源;沉积物质量基准分析表明,对底栖生物可能产生毒性效应的重金属主要是Cd和Hg,主要分布在章水段和桃...     

汕头湾表层沉积物重金属污染与潜在生态风险评价

汕头湾作为华南地区重要的出海门户,汕头市主要的旅游区和水产养殖基地,其环境污染问题已成为制约当地经济发展的重要因素,为此2002年在此开展了重大科技术兴海项目,以海洋沉积物质量标准、单因子污染指数和潜在生态风险评价体系对汕头湾表层沉积物重金属污染现状和潜在生态风险进行了评价。结果表明:汕头湾表层沉积物中Cd,Cu,Pb,Zn的平均含量超过海沉积物质量标准(Ⅰ类);以单因子污染指数评价,Cd达到很强污染等级,Zn为强污染,Cu,Ni,Pb为中等污染;以单元素生态系数(E_rⁱ)评价,只有Cd的潜在生态风险达到很强等级,其它元素则只属于轻微潜在风险范畴;以多元素潜在生态风险指数(RI)评价,汕头湾的潜在生态风险水平处于中等强度;重金属含量分布特征与重金属污染及潜在生态风险的空间差异性一致,表现为由上游至下游呈波状递减趋势,其中以牛田洋和汕头港上游最为严重;这一污染特征主要是由集水区域内的产业结构特点、河流入海口及排污口的分布以及汕头湾的地理和水文特性所决定的。     

乐安江沉积物中金属污染的潜在生态风险评价

选择污染严重的乐安江河流沉积物为对象,利用风险因子Ｅ和风险指数ＲＩ等定量诊断工具开展沉积物中重金属污染的潜在生态风险评价。根据风险指标体系和空间分异规律,将流域划分居不同特征的４种生态风险功能区。对比评价效果。潜在生态风险评价与地积累 情况大同小异,可以相互补充和借鉴。     

北京市南沙河沉积物重金属污染特征及风险评价

北京南沙河是海淀北部地区的重要排水和风景观赏性河道,为全面了解南沙河底泥沉积物中重金属的污染特征,采集了表层沉积物样品,分析了重金属元素的含量和形态,并利用单因子指数法、Hakanson综合污染指数法和潜在生态风险指数法对沉积物重金属进行了生态风险评价.结果表明:南沙河表层沉积物各种重金属元素存在较好的同源性,污染程度为:Cr＞Cd＞Zn＞Cu＞Pb＞Ni.基于单项潜在生态风险指数的评价表明,该区域重金属生态风险等级由强至弱依次为:Cd＞Pb＞Cu≈Cr＞Ni≈Zn,其中,仅Cd具有较高的潜在生态风险,综合潜在生态风险指数表明,除了京藏高速桥河段危害等级较高外,南沙河总体处于轻微的生态风险等级.形态分析表明,Cd的酸提取态含量高,迁移性最强,最容易对生物造成直接危害,其次是Pb和Zn,Cu和Ni具有一定程度的潜在环境危害,Cr产生环境危害的可能性较小.     

瓯江下游流域河流沉积物重金属污染特征、来源及潜在生态风险评价

为了解瓯江下游流域及沿岸城郊入江河流沉积物中重金属的污染特征, 对瓯江流域下游及温州城区河流43个表层沉积物中Cr、Co、Ni、Cu、Zn、As 和Pb 共7 种重金属元素的含量特征进行分析, 比较了城郊与城区、城区入江口与城区内部之间河流沉积物重金属含量的特征及差异并探讨其污染来源。结果表明: 沉积物中7 种重金属元素的含量由高到低依次为: Zn>Cr>Cu>Ni>Pb>Co>As, 与浙江省土壤背景值相比, 7 种重金属的平均含量超标1.5-4.9 倍,各种重金属的污染程度依次为: Co>Ni>Cr>Zn>As>Cu>Pb, 综合污染程度已达到警戒线等级。来源分析表明, 重金属元素Cu、Zn、Pb 和Cr 主要来自于工业污水排放及船舶交通等人类活动, Co 和As 主要来自于工业及农业生产活动, Ni主要来自于以工业为主的排污污染。潜在生态风险系数Eri 评价结果显示, 7 种重金属潜在生态风险大小为:Co>As>Cu>Ni>Pb>Cr>Zn, Co 元素处于较强生态风险等级; 潜在生态风险指数RI 介于72.05-107.80 之间, 其中55.5%的样点处于较强生态风险水平, 44.4%为中等生态风险水平, 研究区整体处于较强生态风险水平。     

厦门杏林湾表层沉积物重金属污染特征及潜在生态风险评价

论文对杏林湾表层沉积物重金属、有机碳和硫化物含量进行了检测,对数据作了相关性分析和因子分析,并应用潜在生态危害指数法对重金属的潜在生态风险进行了评价。结果表明:重金属之间有显著的相关性,Cu与Ni、Pb与Ni、Pb与Cr以及Cr与Hg之间的相关系数分别为0.786(P﹤0.05)、0.783(P﹤0.05)、0.937(P﹤0.01)和0.770(P﹤0.05)。重金属与有机碳及硫化物的相关性较差,表明该地区重金属污染来源与硫化物和有机碳并不相同。既有人为输入,又有自然的沉积过程。因子分析进一步解释了该水域重金属污染的主要来源。根据E_rⁱ均值大小,Hg的危害风险最大,Cr最小。6种重金属潜在生物毒性风险大小依次为:Hg > Pb > Cu > Cd > Ni > Cr。重金属的生态危害程度均较小,尚属轻微生态危害。     

湖南省主要水系底泥重金属污染特征及其生态风险评价

为全面了解湖南省主要水系底泥中重金属含量及其潜在生态风险,在湖南省内的湘、资、沅、澧以及洞庭湖5个主要水系共采集了75个位点的底泥样品,分析了重金属元素含量和来源分布特征,并采用地累积指数法、内梅罗指数法和潜在生态风险指数法对其污染程度和潜在生态风险进行评价。结果表明,As、Cd、Cr、Cu、Mn、Pb和Zn的平均含量分别为32.87、7.59、78.09、70.69、1182.60、85.64 mg/kg和482.44 mg/kg。湘江和洞庭湖的污染相对严重,底泥中重金属含量明显高于资江、沅江和澧水;相关性分析表明多种重金属具有相同污染来源;地累积指数评价结果显示,湖南省主要水系底泥中Cd为重污染水平,Zn为中度污染,Cu、Mn和Pb均为轻度污染,而As和Cr污染程度为清洁;内梅罗指数法评价结果表明,除Cr为轻度污染外,湖南省主要水系底泥中其他6种重金属污染均为重污染级别;潜在生态风险评价结果显示,湖南省总体潜在生态风险属于中等级别,各水系潜在生态风险大小顺序为洞庭湖>资江>湘江>澧水>沅江,重金属Cd的潜在生态风险级别为很强,其他重金属元素都属于轻微级别。     

河口潮间带沉积物重金属累积及生态风险评价

于2015年7月份在闽江口鳝鱼滩湿地布设两条样带(T1和T2),并分别选取5个采样点采集沉积物样品。因重金属Co和V对动物和人类会造成一定危害,且闽江河口潮间带Co和V的研究较少,则对其理化性质、Co和V的空间分布特征以及污染程度等进行了研究,旨在为Co和V的污染研究提供参考。结果显示,该沉积物中Co和V的平均浓度分别为15.19 mg/kg、102.94 mg/kg,均高于福建省背景浓度,与其他河口对比,Co和V浓度处于中等水平。Co和V的含量由陆向海方向略有下降。地累积指数法分析得出沉积物中Co含量呈现轻度污染状态,V呈现无污染状态。此外,Co和V的潜在生态危害系数E_rⁱ分别为7.24—14.85和1.47—4.17,表明潜在生态危害轻微,闽江河口潮间带沉积物中Co和V属于轻度污染。     

The effects of heavy metals on microbial biomass in sediments of Palestine Lake

Effects of metal contamination on microbial biomass in sediment samples from three areas in Palestine Lake (one area highly polluted with chromium, cadmium and zinc) were determined. Adenosine triphosphate (ATP) concentrations, determined by the luciferin-luciferase bioluminescent technique, and microbial colony numbers on pour plates were used as biomass indicators. Plate counts showed a significant (P < 0.01) site effect with the highly contaminated area having an order of magnitude lower microbial population than the control area. ATP concentrations also indicated lower microbial biomass in contaminated sediments. The metal concentrations of the most contaminated area averaged 17,840 µg Zn/g, 4380 µg Cr/g and 585 µg Cd/g based on dry weight of sediments. A suppression of organic decomposition was evident in the impacted area; high metal levels and resultant low microbial biomass may have been causative.     

The current status of heavy metal in lake sediments from China: Pollution and ecological risk assessment

Heavy metal contamination in lake sediments is a serious problem, particularly in developing countries such as China. To evaluate heavy metal pollution and risk of contamination in lake sediments on a national scale in China, we collated available data in the literature of the last 10 years on lake sediments polluted with heavy metals from 24 provinces in China. Based on these data, we used sediment quality guidelines, geoaccumulation index, and potential ecological risk index to assess potential ecological risk levels. The results showed that approximately 20.6% of the lakes studied exceeded grade II level in Chinese soil quality standards for As, 31.3% for Cd, 4.6% for Cu, 20.8% for Ni, 2.8% for Zn, and 11.1% for Hg, respectively. Besides, the mean concentrations for As in 10.3% of lakes, Hg in 11.9% of lakes, and Ni in 31.3% of lakes surpassed the probable effect level. The potential ecological risk for toxic metals decreased in the order of Cd > Hg > As > Cu > Pb > Ni > Cr > Zn, and there were 21.8% of the lakes studied in the state of moderate risk, 10.9% in high risk, and 12.7% in very high risk. It can be concluded that Chinese lake sediments are polluted by heavy metals to varying degrees. In order to provide key management targets for relevant administrative agencies, based on the results of the pollution and ecological risk assessments, Cd, Hg, As, Cu, and Ni were selected as the priority control heavy metals, and the eastern coastal provinces and Hunan province were selected as the priority control provinces. This article, therefore, provides a comprehensive assessment of heavy metal pollution in lake sediments in China, while providing a reference for the development of lake sediment quality standards.     

Pollution and health risk assessment of heavy metals in urban soil in China

The pollution and potential health risk due to lifetime exposure to heavy metals in urban soil of China were evaluated, based on the urban soil samples collected from published papers from 2005 to 2014. The contamination levels were in the order of Cd > Hg > Cu > Zn > Pb >As > Ni > Cr, and Hg and Cd fell into the category of “moderately contaminated” to “heavily contaminated.” The non-carcinogenic risk for different populations varied greatly, among which children faced high risk, and then the adult female and adult male followed. The hazard index (non-carcinogenic risk) higher than 1.00 occurred in Shanghai, Gansu, Qinghai, Hunan, and Anhui, whereas most of those in northern and western China had low risks. For the carcinogenic risk, Anhui and Ningxia provinces had urban soils exceeding the safe reference (1 × 10^?6–1 × 10^?4). Qinghai and Gansu had high carcinogenic risks since their risk indexes were much closer to the reference, and the others were in low risk.     

Pollution and ecological risk assessment of antimony and other heavy metals in soils from the world's largest antimony mine area,China

Xikuangshan is located in Lengshuijiang City, Hunan province, China. With intensive mining and metallurgical activities, large amounts of tailing containing heavy metals (in this study, the term “heavy metals” is used for both metals and metalloids) were introduced to the soils around the mine area. Those heavy metals including antimony and other heavy metals would pose huge risk to human health and ecological environment. With a view to providing information on the extent of contamination and potential ecological risk of heavy metals in the soils of this mine area, the total contents of antimony (Sb), manganese (Mn), zinc (Zn), arsenic (As), cadmium (Cd), and lead (Pb) in the soils were examined. The results revealed that the predominant pollutants in this area were Sb, Cd, and Zn with mean concentrations being 356.58, 9.98, and 486.42 mg kg^?1, 119.66, 117.41, and 5.17 times of the corresponding background values respectively. The pollution indices (Ps) indicated that the pollution levels of all sampling zones were serious including the control zones. The ecological risk levels of all heavy metals were very high on all the sampling zones except sampling zone 7 (as considerable), and Sb, Cd, and As were regarded as making great contribution to the risk indices (RI).     

湘西河流表层沉积物重金属污染特征及其潜在生态毒性风险

花垣河和峒河是湘西地区受到锰矿和铅锌矿生产影响严重的两条河流。通过表层沉积物采样分析了Cd、Pb、Cu、Ni、Cr、Zn和Mn的总量,根据BCR连续提取程序分析沉积物样品中重金属的地球化学赋存形态,采用内梅罗指数法和地积累指数法评价了沉积物重金属污染特征,根据重金属的富集程度探讨了重金属污染来源,采用淡水生态系统沉积物质量基准(SQGs,TEL/PEL)和毒性单位评价了花垣河和峒河沉积物中重金属元素的生态毒性风险。结果表明,花垣河和峒河绝大多数位点的表层沉积物中Cd、Pb、Cu、Ni、Cr、Zn和Mn的总量高于参照点,形成严重的复合污染,花垣河沉积物中重金属的污染水平明显高于峒河,但沿程变化规律不明显,而峒河沉积物中重金属的沿程变化较有规律,即上游含量低,中下游含量较高。两条河流表层沉积物中富集程度居前列的均为Cd、Pb、Zn和Mn。花垣河和峒河沉积物重金属污染主要来源于矿业生产所产生废渣和废水的点排放。在花垣河和峒河的大多数位点,Cd、Pb和Mn的形态具有共同特征,其生物可利用态均较大程度地超过生物不可利用态,而且Mn和Cd的生物可直接利用态所占比例远高于其它重金属,而Cu和Cr的生物可直接利用态所占比例很低。花垣河沉积物中Cd、Pb和Zn在所有位点极大地超过PEL,在峒河中下游,Cd、Pb、Ni和Zn超过PEL,具有较大的潜在生物毒性。除上游S1位点外,花垣河的其余各位点都具有明显的急性毒性,峒河中下游各位点具有明显的急性毒性,这些河段需要重点治理。     

Distribution,speciation, and ecological risk assessment of heavy metals in surface sediments of Jiaozhou Bay,China

This paper analyzed the distribution and speciation of seven heavy metals in sediments in Jiaozhou Bay. The ecological risk was assessed using three index approaches (i.e., risk assessment code (RAC), contamination factor (CF), and potential ecological risk index (PERI)) and by a comparison with sediment quality guidelines (Chinese Marine Sediment Quality Standards (CMSQS), and threshold effect level (TEL) and probable effect level (PEL) from the USEPA). Pb, Cr, As, Cu, Zn, and Hg contents at most sites were above the corresponding TEL and Class I criteria (CMSQS) value. Particularly, high contents of Cu, detected at sites S₇ (124.5 mg kg^?1) and S₈ (118.3 mg kg^?1), exceeded the respective PEL value, indicating that harmful biological effects might occur. Speciation analysis, individual CF, and RAC calculations suggested that Cd had the highest bioavailable fraction and thus posed a very high risk to aquatic ecosystem; Cu and Zn showed a medium–high risk. Both global CF and PERI analysis indicated a high pollution risk at sites S₇, S₁, S₃, and S₂, but the assessments of specific sites were different. The incomplete consistency suggested that it is necessary to consider both total contents and chemical speciation for providing a more realistic appraisal for the risk of heavy metals in sediments.