Over One Hundred Year Sedimentary Record of Polycyclic Aromatic Hydrocarbons in the Andaman Sea, Malaysia

[摘要]：采用GCPMS 分析研究了马来西亚海域安达曼海兰卡威岛邻近海域沉积物柱样(WC02) 中多环芳烃(PAHs) 组成与含量的 垂直分布特征, 结合210Pb定年, 重现了该海域近百年来PAHs 的沉积历史( 1898~ 2004 年) . 研究表明, PAHs 在整个沉积剖面( 0 ~ 56 cm) 的含量介于1312~ 6011 ng# g- 1 之间( 平均值2814 ng# g- 1) , 所分析的PAHs 中以菲、萘、等化合物为主, 与当地周边海 域相比污染程度较轻. 在20 世纪20 年代以前, 沉积物中多环芳烃含量较低, 基本代表当地环境的本底值, 即多环芳烃主要来 源于天然物质的输入; 20 年代以后PAHs 的总量有所上升, 并在20 世纪60 年代和80 年代出现了2 个峰值, 表明这段时间内多 环芳烃的陆源输入特征比较明显, 也反映了人类活动在20 世纪20 年代后开始对该海域产生一定的影响. 采用母体、高低环 PAH 比值对沉积物柱样中PAHs 的来源进行分析, 表明该海域沉积物受到燃料不完全燃烧产物污染为主、并伴有石油类污染, 这与马来西亚西海域周边地区的人类活动( 工农业生产、进出口、海上活动等) 密切相关, 同时也受到马六甲海峡繁忙的海上 交通运输影响. 对沉积物柱样污染历史进行分析, 表明PAHs 含量的阶段性变化与该地区不同时期的人文活动和社会经济( 国 内生产总值) 的发展状况密切相关, 较好地反映了人类活动对环境的影响.[Abstract]:Polycyclic aromatic hydrocarbons (PAHs) in a sediment core collected from Langkawi Island of the Andaman Sea, Malaysia were determined by GCPMS, the vertical variations of concentration and distributions of PAHs were investigated. In combining with 210Pb2dating, the PAHs sedimentary record in the last 100 years was reconstructed and their possible sources were also discussed. The EPAH concentration ranged from 131226011 ng#g- 1 in the whole sedimentary section ( 0256 cm) with the dominant compounds of phenanthrene, naphthalene and perylene. The sediments contaminated to a lesser extent comparing with the surrounding waters. Before the 1920s, the concentrations of PAHs were considered to be the background level, which was implied from the natural inputs. The historical records of PAHs in the core showed that two distinct peaks which represented the input time of 1960s and 1980s, respectively, inferred that there were some relatively dramatically land2based inputs, and human activities leaded a clear impact to these waters during these periods. Furthermore, PAHs diagnostic ratios indicated that PAHs in the core sediments were mainly of pyrolytic origin ( combustion) , accompanied with minor petroleum origin. These were related with agriculture, industry, ocean import and export, and shipping activities in the surrounding regions. Meanwhile as the vital communication line, the marine transportation of the Strait of Malacca had influenced the environmental quality of the Andaman Sea. Meanwhile, based on the sedimentary record, PAHs concentrations were found to correlate positively with humanism activities and socioeconomic development (Gross Domestic Production) in the surrounding regions.国家自然科学基金项目( 20777060) ; 国家海洋局海洋三所 科技项目( 海三科2007021

Rapid enrichment and analysis of --(137)Cs in seawater

以亚铁氰化铜(CufC)作为吸附剂,采用循环吸附的方法制备用于海水中137CS富集的富集材料,同时采用湿样制源的方法制备样品源.研究结果显示当流量在5.0、6.0 dM3/MIn,且富集体积保持在900 dM3以下时,对海水中137CS的富集效率保持在85%以上,且随富集体积的变化并不明显;当流量增大到7.0、8.0 dM3/MIn,且富集体积从500 dM3增大到1 000 dM3时,其富集效率从85%左右下降到75%左右,呈现出明显的下降趋势;而当流量进一步增大到10 dM3/MIn时,富集效率急剧下降到68%左右.研究结果表明,将流量控制在5.0--8.0dM3/MIn且富集体积在500 dM3以下时,可以在保证较高的富集效率的同时有效地减少富集时间,达到快速富集的目的.此外,湿样制源的方式缩短了样品前处理时间,提高了样品处理效率.本研究中所使用的海水中137CS的富集和分析方法总计耗时约需8H左右,只相当于传统分析方法耗时的1/5左右.137Cs,which emits β and γ rays,is an important nuclide released from a nuclear explosion or nuclear power plant.Once absorbed by humans or other animals,it accumulates in muscle tissue and adversely affects health.Investigation of the radioactivity of 137Cs in seawater is an important component of the background survey carried out before the construction of a nuclear power plant,but at present,the analysis of 137Cs in seawater is tedious and prolonged because of the inappropriate materials and complicated processing methods used.To adapt to the macro-trend of the development of nuclear power in China and to answer the call for rapid analysis of 137Cs in seawater,this work prepares impregnated cartridges for 137Cs in seawater employing a cycling method based on copper ferrocyanide(CuFC),which easily attaches to the support material because of its gelatinous form and highly selective absorption to 137Cs.Seawater was pumped through a series of four cartridges,two impregnated cartridges following two blank cartridges,and the impregnated cartridges were then directly transformed to have the same geometry after enrichment and were subjected to measurements with an HPGe γ detector.The results show that the concentration efficiency of a cartridge exceeded 85% when the flow was 5.0 or 6.0 dm3/min and the volume of seawater was kept below 900 dm3,decreased from 85% to 75% when the flow increased to 7.0 or 8.0 dm3/min and the volume of seawater increased from 500 to 1 000 dm3,and then dropped sharply to 68% when the flow increased to 10.0 dm3/min.The results show that the concentration efficiency of the cartridge is relatively high with shorter concentration time when flow was maintained between 5.0 and 8.0 dm3/min and the volume of seawater was kept within 500 dm3,and the sample preparation efficiency improved employing the wet sampling method.With the method proposed in this paper,the enrichment and determination time for 137Cs is about 8 hours,just one-fifth of that of the traditional method.国家海洋公益性行业科研专项经费资助项目(200705028

Progresses of Radium Isotopes Applications to Oceanography Research

镭同位素具有不同的半衰期,可以用来研究不同时空尺度的海洋学过程,在海洋学研究中得以广泛应用。镭同位素在海洋学中的应用主要包括溶解态物质输运,水体停留时间的估算,海洋地下水排放,沉积物的地球化学和放射年代学以及海洋水团分析5个方面的内容。从海洋中镭同位素的地球化学行为、测量方法及其在以上5个方面的研究综述了镭同位素海洋学研究进展,比较了海洋中镭同位素测量方法,阐释了各应用领域的示踪原理,给出各种应用的方法模式及公式,总结了镭同位素海洋学的发展变化,并指出我国镭同位素海洋学的发展前景和方向。Having different half-lives,Radium isotopes can be used to study marine processes with different timescales,which have been widely used in oceanography research.The applications of radium in oceanography research consist mostly of five aspects: the transportation of dissolved material,the estimation of the residence time of seawater,the submarine groundwater discharge,the geochemistry and radio chronology of the sediments,the quantitative analysis of seawater mass.In this paper,the progresses of radium isotopes are reviewed from its geochemical behaviors,measuring methods and the five application aspects mentioned above.The measuring methods are compared with each other.The principles,method models and formulas of the five application aspects are illustrated.The progresses of radium isotope oceanography are overviewed.The development direction and prospects of marine radium research in our country are suggested.国家海洋局第三海洋研究所基本科研业务费专项资金资助项目“台湾海峡上升流区水体混合过程的镭同位素示踪研究”(编号:2009050);国家重点基础研究发展计划项目“中国东部陆架边缘海海洋物理环境演变及其环境效应——典型水域生源循环及浮游生物多样性对物理环境演变的响应”(编号:2005CB422305)资