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1.
In order to investigate the pollution levels, sources and ecological risks of arsenic (As) and heavy metals (Cr, Ni, Cu, Zn, Pb and Cd) in inshore sediments of the Yellow River estuary, the surface sediment in areas of inshore coastal waters were sampled in October 2014 as the flow-sediment regulation project (FSRP) was implemented for 13 years. Results showed that the concentrations of As and heavy metals in inshore sediments of the Yellow River estuary were in the order of Zn?>?Cr?>?Cu?>?Ni?>?Pb?>?As?>?Cd. Higher levels of As, Cr, Ni, Cu, Zn and Pb generally occurred in fine-grained sediments of the Yellow River estuary and the southeast region, which was consistent with the spatial distribution of clay. In contrast, higher concentrations of Cd were generally observed in northwest area of the Yellow River estuary and near the Qingshuigou estuary, which showed similarly spatial distribution with that of sand. The sediment quality guidelines (SQGS) and geoaccumulation indices (Igeo) indicated that the inshore sediments were polluted by Cu, Cd, As, Pb and Zn, and, among them, Cd pollution was more serious. Ecological risk indices (E r i ) demonstrated low risks for Cr, Ni, Cu, Zn, Pb and As, and high potential toxicity by Cd. The integrated ecological risk index implied that 6.8% of stations presented moderate risk, 4.5% of stations exhibited disastrous risk, and 88.7% of stations demonstrated considerable risk. Principal component analysis indicated that Ni, Cu, Zn, Pb and As might originate from common pollution sources, while Cr and Cd might share another similar sources. With the continuous implementation of FSRP, As and heavy metal levels in inshore sediments of the Yellow River estuary could be classified as stage I (2002–2010) and stage II (2010–2014). In the stage I, As, Cr, Ni, Cu, Zn and Pb levels fluctuated but decreased significantly, whereas Cd concentrations showed little variation. In the stage II, As and heavy metal levels significantly increased although some little fluctuations occurred. The continuous accumulation of As and heavy metals (especially for Cd) in inshore sediments of the Yellow River estuary would occur again as the FSRP was implemented for 9 years (since 2010). The ecotoxicological risk of Cd, As, Ni and Cu in inshore sediments might be more serious since the accumulation of the four elements would be continuously occurred in future years. Next step, there will be long-term potential consequences for marine organism if effective measures are not taken to control the loadings of metal pollutants into estuary.  相似文献   

2.
白洋淀沉积物-沉水植物-水系统重金属污染分布特征   总被引：6，自引：1，他引：5  
通过对白洋淀沉水植物及对应沉积物和水中Cd、Pb、As含量测定，以期揭示白洋淀沉积物-沉水植物-水系统中重金属污染状况及分布规律，明确不同沉水植物对重金属的富集能力.结果表明，地表水Cd、Pb、As浓度均符合我国地表水I类水质标准，不同采样区重金属浓度差异不显著.上覆水Pb浓度显著高于地表水和间隙水，间隙水As浓度显著高于地表水和上覆水；地积累指数法和潜在生态危害指数法评价结果表明，沉积物中重金属污染程度表现为Cd > Pb > As，Cd污染最严重，达到"轻度-偏重度"污染程度，"中等-极强"生态危害级别，As为清洁水平，不同采样区重金属污染程度表现为生活水产养殖区 > 纳污区 > 淀边缘区；沉水植物重金属富集能力表现为金鱼藻（Ceratophyllum demersum L.） > 菹草（Potamogeton crispus L.）和穗状狐尾藻（Myriophyllum spicatum L.） > 篦齿眼子菜（Potamogeton pectinatus L.）.植物体内重金属含量与体内氮、磷含量呈显著正相关，氮、磷营养盐影响沉水植物对重金属的富集.  相似文献   

3.
Surface soils (0–20 cm) were collected from along a tidal ditch of the Yellow River Estuary in August of 2007. Samples were subjected to a total digestion technique before they were analyzed for total concentrations of As, Cr, Cd, Cu, Ni, Pb, Zn, P and S in order to investigate heavy metal contamination levels in wetland soils nearby the tidal ditches and their main sources. Results showed that the mean concentrations of these heavy metals except for As and Cd were lower than the Class I criteria. Nearly all sampling sites showed lower contamination levels for As and Cd, while no contamination levels for other heavy metals. Cr, Cu, and Ni mainly originated from parent rocks, and Pb and As might originate from tidal seawater and oil field pollution, respectively; while Cd and Zn mainly originated from parent rocks and tidal seawater. Most of heavy metals showed significant correlations with total concentrations of P and S, however, no significant correlations were observed between them and soil pH, slat and soil organic matter.  相似文献   

4.
Sediment from twelve stations was sampled from the Tupilipalem Coast, southeast coast of India, and the presence of a set of heavy metals was established including iron (Fe), manganese (Mn), chromium (Cr), copper (Cu), nickel (Ni), lead (Pb), zinc (Zn) and cadmium (Cd). The heavy metals were assessed by factor analysis, the results of which showed positive and/or negative correlations among Fe, Mn, Cr, Cu, Ni, Pb, Zn, and Cd. Factor analysis also indicated that heavy metals in the sediments of the study area have different natural and anthropogenic sources. Similarly, a sediment pollution assessment was done using the Geoaccumulation Index (Igeo), Enrichment Factor (EF), and Pollution Load Index (PLI). The Geoaccumulation Index indicated that the surface sediment of the Tupilipalem Coast was extremely contaminated with Fe, Mn, Cr, Cu, Ni, Pb, and Zn. The calculation of enrichment factors showed a significant enrichment with respect to Pb, Zn, and Cd and a moderate enrichment with Cr, Cu, and Ni. The falling trend of average contents’ enrichment factors is Cd> Pb> Zn> Cu> Cr> Ni> Mn> Fe. The PLI values of the Cd show higher (>1) values due to the influence of distinct external sources like agricultural runoff, industrial activities, and other anthropogenic inputs. Ninety two percent of heavy metals under study showed the highest concentrations at station TP-5 where the Buckingham Canal and other agricultural and aquacultural effluents connect with the Bay of Bengal. This location is the second inlet which is periodically closed and it seemed that these parts of the study area are heavily affected by anthropogenic pollution.  相似文献   

5.
《Marine pollution bulletin》2014,85(1-2):373-378
The surficial coastal sediments in Kendari Bay are sampled in the field to determine the concentration and pollution level of three heavy metals (Pb, Cd and Cr). Twenty-five sampling points ranging from the inner (Wanggu River) to the outer area of the bay have been chosen. The physicochemical properties, such as temperature, pH, salinity and TDS of the overlying water, as well as the sediment type and TOC of the surficial sediments, are also measured. The total concentrations of the Pb, Cd and Cr in the sediment samples are quantified using inductively-coupled plasma mass spectrometry (ICP-MS). The concentrations of the heavy metals (Pb, Cd and Cr) ranged from 0.84 to 17.02 μg/g, 0.02 to 0.17 μg/g and 1.92 to 40.11 μg/g (dry weight), respectively, following the Cr > Pb > Cd sequence. To assess the degree of contamination, a geoaccumulation index (Igeo) is measured. Kendari Bay is not a contaminated area regarding Pb, Cd and Cr.  相似文献   

6.
Sediment samples were collected from ten selected sites of the lower Meghna River estuary,and six heavy metals were analyzed with Atomic Absorption Spectrophotometry(AAS)to assess the contamination level and the metals’association with sediment grain size.The current results revealed that the mean concentrations of the studied metals were ranked in descending order of iron(Fe)(1.29×103 mg/kg)>zinc(Zn)(42.41 mg/kg)>lead(Pb)(12.48 mg/kg)>chromium(Cr)(10.59 mg/kg)>copper(Cu)(6.22 mg/kg)>cadmium(Cd)(0.28 mg/kg).The geo-accumulation,contamination,and pollution load indexes suggested that the lower Meghna river estuary was not contaminated by Fe,Zn,Pb,Cr,and Cu.The mean size of the sediment ranged from 28.92 to 126.2 mm,and the Pearson correlation coefficient showed a significant association between Fe and Pb(coefficient of determination,r2=0.836;p<0.05),and no significant correlation was found between individual metals and grain size,indicating no or low influence on the metals distribution.  相似文献   

7.
为识别表层沉积物重金属的来源以及量化源贡献,选取鄱阳湖丰水期表层沉积物为研究对象,测定14种重金属(V、Cr、Co、Ni、Cu、Zn、Sr、Mo、Cd、Sb、W、Pb、Hg和As)的含量,分析其污染及空间分布特征,并利用主成分分析法(PCA)和正定矩阵因子分解法(PMF)对沉积物重金属进行源解析.结果表明:除V和Cr外,Cd、Mo、Hg、Cu、Pb、Zn、W、Sr、As、Ni、Co和Sb的平均含量分别为江西省土壤背景值的5.7、2.2、1.9、1.8、1.5、1.5、1.4、1.3、1.3、1.2、1.0和1.0倍; Cd、Hg、Cu、Mo、Pb、Sr和Zn超出江西省土壤背景值的比例相对较高,分别为100%、100%、100%、100%、97%、97%和93%,所有沉积物样品中Cd含量超过农用地土壤污染风险筛选值的比例为51%; V、Cr、Co、Ni、Cu、Zn、Sr、Mo、Sb、W、Pb、Hg和As含量呈未污染至弱污染水平,而Cd含量属于中等污染水平,接近于重污染水平.总体而言,Cd的污染相对较严重.重金属的分布具有显著的区域特征,其中Cr、Cu、Zn、Sr、Pb、Hg和As的空间分布十分相似,表现为在赣江、抚河、信江和饶河入湖口附近区域含量较高,而Co、Ni、Mo和Sb明显在湖区南部、东北部和修水入湖附近这3个区域聚集,Cd和W的空间变异性相对较大,V的含量分布相对较均匀.PCA和PMF解析结果都表明鄱阳湖丰水期表层沉积物重金属受4种来源的共同影响,其中,矿业和工业活动的影响最大,相对贡献率为38%,其次是尾矿和废渣,相对贡献率为28%,再是农业活动,相对贡献率为19%,最后是自然来源的相对贡献率为14%.  相似文献   

8.
Soil samples are collected from 74 sites in Shenyang city, northeast China, and the concentrations, spatial distribution, enrichment factors (EF), and potential ecological and human health risk (Er) of potentially toxic metals (Sr, Zn, Cr, Pb, Cu, Ni, and As) are investigated. The mean concentrations of potentially toxic metals in topsoil follow the order Sr > Zn > Cr > Pb > Cu > Ni > As. Compared with 2011, the contamination magnitude has improved in 2017, but the pollution status still exists, especially for As and Cr. EF and the mean Er of potentially toxic metals decrease following the order As > Pb > Cu > Ni > Zn > Cr > Sr and As > Cu > Zn > Pb > Sr > Ni > Cr, suggesting that the potentially toxic metals in the topsoil of Shenyang city mainly come from natural sources, and the potential ecological risk for potentially toxic metals is low. There are potentially non‐carcinogenic and carcinogenic health risks, but they are not considered significant. For non‐carcinogenic health risks, oral ingestion is the main exposure pathway, and Cr and Pb are the major pollutants. Finally, As is found to be the main carcinogenic contamination metal.  相似文献   

9.
分析了阳宗海柱状及表层沉积物中Al、Fe、Mn、Zn、Cr、Co、Ni、Cu、As、Cd、Pb等金属元素的含量,结合沉积年代学,研究了沉积物重金属污染的时空变化和潜在生态风险特征.结果表明,表层沉积物中重金属含量具有一定的空间差异性,As、Cd、Cu、Pb和Zn在中东部湖区含量较高,而Cr、Co、Ni含量高值位于南、北湖区的近岸区域;柱状沉积物中,1990s之前As、Cd、Cu、Pb和Zn含量较为稳定,1990s中后期以来,其含量逐渐增加,并在2009-2010年前后达到最大值,此后逐渐下降;而柱状沉积物中Cr、Co、Ni含量变化趋势与Al、Fe相似,总体上由下向上逐渐降低,这主要与沉积物质地(粒度)逐渐变粗有关.重金属富集系数表明,阳宗海沉积物中主要污染元素为As、Cd、Cu、Pb和Zn,1990s中后期污染程度快速增加,2009-2010年前后达到峰值,此后污染程度逐渐降低;表层沉积物中Cu为未污染至"弱"污染水平;Zn、Pb为"弱-中等"污染水平,As为"中等-强"污染水平,Cd为"弱-强"污染水平,中东部湖区污染程度高于其他湖区,这可能与该湖区缺少入湖径流、自然碎屑物质沉积速率较低以及砷污染事件等人为源的重金属贡献影响更为显著有关.生态风险评价结果表明,在2002-2010年前后沉积物重金属达到"中等-强"潜在生态危害,主要贡献因子是Cd和As,近年来其生态风险等级逐渐降低;表层沉积物中重金属在中东部湖区具有"中等"程度潜在生态危害,而其他湖区表层沉积物重金属具有较低程度的潜在生态风险.  相似文献   

10.
太湖流域滆湖底泥重金属赋存特征及其生物有效性   总被引：1，自引：0，他引：1  
包先明  晁建颖  尹洪斌 《湖泊科学》2016,28(5):1010-1017
为了探讨太湖流域滆湖底泥重金属(Cd、Cr、Cu、Zn、Ni和Pb)的赋存特征及其生物有效性,对底泥重金属总量、形态以及生物富集量进行了分析.结果表明,6种重金属含量的空间分布表现为北部湖区最高,其次为南部湖区,中部湖区最低,重金属Ni、Cu、Zn和Pb含量显著高于沉积物背景值,分别是背景值的4.77、3.89、2.96和2.76倍,重金属总量与沉积物中的黏土成分含量具有显著相关性.采用三级四部提取法对重金属形态进行分析表明,6种重金属的生物有效态(弱酸结合态、可还原态和可氧化态之和)含量顺序为CdCuZnPbNiCr,其中Cd、Cu、Zn和Pb的生物有效态含量分别占总量的84.15%、78.47%、76.50%和64.29%.Cu和Zn在铜锈环棱螺中富集含量要显著高于其他金属元素.相关性分析表明,6种重金属中仅Cr和Pb的生物富集量与有效态含量具有显著相关性,这表明,重金属在生物体内的富集不仅与有效态含量有关,还与底泥重金属总量有关.因此,评价滆湖重金属的生态风险时需要综合考虑重金属的总量及生物有效态含量.  相似文献   

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