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271.
Abstract

Total organic carbon, humic substances, and the species of trace metals (including Cu, Zn, Pb, Cd, Cr, Mn and Fe) in six and seven phases, such as bioexchangeable (P1), skeletal (carbonates, P2), easily reducible (Fe and Mn oxides, P3), moderately reducible (crystalline Mn oxides, P4), organic matters with sulphides (P5), and detritus with minerals (P6) as well as organic with humic substances (PB4) and organic residues (PB6), were analyzed in sediments from the Taiwan Erhjin coastal (including river and estuarine) area, where places we found the copper pollution. Results indicate that higher percentages of P1 and P2 for copper, zinc, lead, cadmium and manganese in samples collected in March and September of 1990 were much higher than those in P3-P6. High percentages of chromium and iron in samples respectively collected in March and September of 1990 were found in P6. for the seven phase analysis, higher percentages of copper species in PB4 and PB6 as well as iron species in PB7 were observed. On the other hand, purified humic acid with the high contents of manganese and iron in humic acid as well as purified fulvic acids were generally found at the upstream stations; and low values at coastal stations. However, extremely high copper (as high as 1750μg g?1, dry weight in fulvic acid and 820μg g?1 in humic acid) and lead (821μg g?1 in humic acid) concentrations with relatively high manganese and iron concentrations were observed in humic substances from the station near the copper recycling area. Comparing the results obtained from the Antarctic Ocean sediments with those from the Taiwan Erhjin Chi coastal sediments, the human impacts on the latter are evaluated.  相似文献   
272.
刘海  魏伟  宋阳  潘杨 《环境科学》2023,44(11):6106-6115
为阐明霍邱县城西湖和城东湖沉积物重金属的环境容量,在城西湖和城东湖各采集了30件沉积物样品,运用综合环境容量指数法(PI),研究了城西湖和城东湖沉积物重金属环境容量特征及空间分布规律,估算了静态和动态环境容量,预测了近百年的变化趋势.结果表明,城西湖和城东湖沉积物中As、 Cd、 Cr、 Cu、 Hg、 Ni、 Pb和Zn含量均值未超过国家规定的土壤风险筛选值;城西湖和城东湖沉积物各重金属元素单项环境容量指数平均值大小分别为:Ni(0.81)相似文献   
273.
Total organic carbon, humic substances, and the species of trace metals (including Cu, Zn, Pb, Cd, Cr, Mn and Fe) in six and seven phases, such as bioexchangeable (P1), skeletal (carbonates, P2), easily reducible (Fe and Mn oxides, P3), moderately reducible (crystalline Mn oxides, P4), organic matters with sulphides (P5), and detritus with minerals (P6) as well as organic with humic substances (PB4) and organic residues (PB6), were analyzed in sediments from the Taiwan Erhjin coastal (including river and estuarine) area, where places we found the copper pollution. Results indicate that higher percentages of P1 and P2 for copper, zinc, lead, cadmium and manganese in samples collected in March and September of 1990 were much higher than those in P3-P6. High percentages of chromium and iron in samples respectively collected in March and September of 1990 were found in P6. for the seven phase analysis, higher percentages of copper species in PB4 and PB6 as well as iron species in PB7 were observed. On the other hand, purified humic acid with the high contents of manganese and iron in humic acid as well as purified fulvic acids were generally found at the upstream stations; and low values at coastal stations. However, extremely high copper (as high as 1750μg g-1, dry weight in fulvic acid and 820μg g-1 in humic acid) and lead (821μg g-1 in humic acid) concentrations with relatively high manganese and iron concentrations were observed in humic substances from the station near the copper recycling area. Comparing the results obtained from the Antarctic Ocean sediments with those from the Taiwan Erhjin Chi coastal sediments, the human impacts on the latter are evaluated.  相似文献   
274.
自1970年代以来,因吴起油田的发现,吴起县石油开采及相关工程建设频繁,各项工程建设在为吴起县带来经济发展的同时也引发了大量滑坡灾害。以"陕西省延安市吴起县地质灾害详细调查"项目为依托,对县内滑坡的类型及分布情况进行了较为详细的野外调查。根据调查结果将滑坡分为黄土层内滑坡、黄土-红粘土接触面滑坡、红粘土-基岩接触面滑坡和黄土泥流滑坡四类,并对滑坡灾害的时间、空间及时空分布特征进行了分析,最后提出相关防治对策。  相似文献   
275.
Thirteen surficial sediment samples, two sediment cores and mussels (Mytilus galloprovincialis) from six locations were collected from Thermaikos gulf, Greece and analyzed for herbicides, organochlorine compounds and aliphatic hydrocarbons. Herbicide concentrations were low in surface sediments (not detected‐0.8 ng/g dry wt) and undetectable in subsurface samples. Organochlorine concentrations ranged between 0.8 and 88.2 ng/g dry wt for the polychlorinated biphenyls (PCBs) and between 1.7 and 22.8 ng/g dry wt for the SDDTs, while aliphatic hydrocarbon values varied from 28.8 to 965.4 ng/g dry wt. The highest concentrations for all the pollutants were measured in the vicinity of the city of Thessaloniki. Petroleum‐related hydrocarbons were dominant in surface sediments, while were still detected till about 1 m depth in the sediment core. Mussels presented low organochlorine concentrations (3.6–10.5 ng/g dry wt for the PCBs, 12.2–34.0 ng/g dry wt for the DDTs), but petroleum hydrocarbon concentrations were rather increased, mainly in the samples collected along the east coastline of the gulf (aliphatic hydrocarbons 52.3–224.3 μg/g dry wt).  相似文献   
276.
淮南—蚌埠段淮河流域沉积物中PAHs的分布及来源辨析   总被引:2,自引:1,他引:1  
彭欢  杨毅  刘敏  李勇  张谦栋  杨刚 《环境科学》2010,31(5):1192-1197
采用GC-MS对淮南至蚌埠段淮河流域水源地、支流及排污口采集沉积物中18种多环芳烃(PAHs)进行定量分析.结果表明,研究区水源地及其支流沉积物中PAHs含量范围为308.12~1090.37ng/g;排污口沉积物PAHs范围为1308.36~8793.16ng/g.沉积物PAHs组成以3~4环PAHs为主,5~6环PAHs相对较少.相对于TOC,BC与沉积物总PAHs的含量相关性更好.PAHs组成特征、主成分分析及多特征比值揭示淮南至蚌埠段淮河流域沉积物PAHs主要来源于化石燃料的不完全燃烧,还有少量石油类产品的输入.生态风险评价结果显示,研究区沉积物中多数PAHs化合物已超出ER-L值和ISQV-L值,而姚家湾排污口沉积物PAHs部分化合物已超出ER-H值和ISQV-H值,表明沉积物中的PAHs对研究区环境已造成了极大的生态风险.  相似文献   
277.
悬浮颗粒物对有机污染物的吸附降低了其表观生物富集系数,这一过程是否同时能够减弱有机污染物对水生生物的毒性却少有报道.因此,本研究选取海河干流二道闸沉积物为悬浮颗粒物,以阿特拉津为目标污染物,斑马鱼为目标生物,进行急性毒性试验.结果表明,无悬浮颗粒物时,阿特拉津对斑马鱼的96 h半致死浓度(96h-LC50)为29.06 mg·L-1,95%置信区间为24.41~40.70 mg·L-1,悬浮颗粒物浓度为7500mg·L-1和15000 mg·L-1时这一指标分别为30.74 mg·L-1和39.51 mg·L-1,对应的95%置信区间分别为27.17~40.91 mg·L-1和30.43~126.93 mg·L-1.并且无悬浮颗粒物、7500 mg·L-1悬浮颗粒物、15000 mg·L-1悬浮颗粒物3组染毒系列中出现的最大无效应浓度分别为3、9和15 mg·L-1.研究表明,悬浮颗粒物的存在降低了阿特拉津对斑马鱼的急性毒性.  相似文献   
278.
随着碳纳米管的广泛应用,其将不可避免地进入环境中.由于其具有极好的吸附亲和力和吸附容量,碳纳米管可以充当环境中持久性有毒污染物的载体,从而改变共存污染物的生物有效性和生态毒性.为评价淡水沉积物中不同多壁碳纳米管(MWCNTs)对Cd和BDE-47生态毒性的影响,采用沉积物慢性生物测试研究了不同浓度MWCNTs存在下Cd和BDE-47对铜锈环棱螺肝胰脏抗氧化防御系统关键成分超氧化物歧化酶(SOD)与Ⅱ相解毒反应的关键酶谷胱甘肽-S-转移酶(GST)以及脂质过氧化损伤指标丙二醛(MDA)的影响.结果表明,沉积物中低浓度MWCNTs(0.5 mg·g~(-1))增强Cd对铜锈环棱螺的氧化胁迫,中、高浓度(5、50 mg·g~(-1))MWCNTs引起Cd对铜锈环棱螺的氧化损伤,MWCNTs的存在显著增强了沉积物中Cd对铜锈环棱螺的毒性,而且具有浓度-效应关系;低浓度MWCNTs不影响BDE-47对铜锈环棱螺的毒性,中、高浓度MWCNTs显著降低BDE-47的毒性,同样具有明显的浓度-效应关系.因此,在评价MWCNTs的潜在环境风险时,不仅考虑MWCNTs自身的毒性,还应当考虑MWCNTs的浓度、共存污染物的种类和MWCNTs与共存污染物之间的相互作用.  相似文献   
279.
北江流域抗生素污染水平和来源初探   总被引:1,自引:0,他引:1  
北江是发源于湖南(武水)和江西(浈水),汇于广东韶关,流经广东全境并入海的三大河流之一。为了解整个北江抗生素污染情况,共设置44个采样点,并采集了河水及部分沉积物样品,较全面地分析了各样品中12种典型抗生素含量并初步探究了其污染来源。研究发现,包括北江源头在内的全河段均有抗生素的检出,5类抗生素在表层水和沉积物中的平均浓度分别为77.8 ng·L~(-1)和3.6 ng·g~(-1)。其中,大环内酯类污染最为严重,其含量范围为11.7~114.6 ng·L~(-1)和0~435.3 ng·g~(-1),远高于其他类抗生素。表层水中磺胺类的磺胺甲恶唑和氯霉素类的检出率达100%,其中以磺胺甲恶唑(14.7 ng·L~(-1))和阿奇霉素(25.0 ng·L~(-1))为主,而沉积物中以阿奇霉素(35.9 ng·g~(-1))、氧氟沙星(5.4 ng·g~(-1))和四环素(3.3 ng·g~(-1))为主。由于流域污染源种类和数量不同,各抗生素在北江中的分布也存在差异。表层水中抗生素含量水平表现为下游高于上中游,在沉积物中则主要集中于中、下游之间河段。这反映了人类活动强度对北江抗生素污染的直接影响。  相似文献   
280.
Due to rapid urbanization and industrialization, heavy metals in road-deposited sediments(RDSs) of parks are emitted into the terrestrial, atmospheric, and water environment, and have a severe impact on residents' and tourists' health. To identify the distribution and characteristic of heavy metals in RDS and to assess the road environmental quality in Chinese parks, samples were collected from Beijing Olympic Park in the present study. The results indicated that particles with small grain size(150 μm) were the dominant fraction. The length of dry period was one of the main factors affecting the particle size distribution, as indicated by the variation of size fraction with the increase of dry days. The amount of heavy metal(i.e., Cu, Zn, Pb and Cd) content was the largest in particles with small size(150 μm) among all samples. Specifically, the percentage of Cu, Zn, Pb and Cd in these particles was 74.7%, 55.5%, 56.6% and 71.3%, respectively.Heavy metals adsorbed in sediments may mainly be contributed by road traffic emissions. The contamination levels of Pb and Cd were higher than Cu and Zn on the basis of the mean heavy metal contents. Specifically, the geoaccumulation index(I geo) decreased in the order:CdPbCuZn. This study analyzed the mobility of heavy metals in sediments using partial sequential extraction with the Tessier procedure. The results revealed that the apparent mobility and potential metal bioavailability of heavy metals in the sediments, based on the exchangeable and carbonate fractions, decreased in the order: CdZn≈PbCu.  相似文献   
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