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1.
南海表层沉积物中有机物分布研究 总被引：3，自引：0，他引：3
对南海表层沉积物中正构烷烃和多环芳烃的含量与分布进行了调查研究。发现南海表层沉积物的正构烷烃碳数分布范围多在Ｃ１６－Ｃ３３,奇偶优势指数ＯＥＰ值略大于１,显示有机质输入有混合源的特征;共检出近６０种多环芳烃化合物,包括萘、菲、蒽、芴、萤蒽、茈化合物的惹烯,Ｂｅｉ等陆源输入标志物。在此基础上,将所获得的数据进行了因子分析,其结果显示南海表层沉积物的物质输入有如下的特点：陆源高等植物输入和燃烧产物的贡 相似文献
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对2003年7月至9月采自北极楚科奇海域的4个站位表层沉积物及1个站位的柱状沉积物样品的总糖、总碳、有机碳、无机碳、总氮、总磷的含量进行了测定,并对其有机碳和有机氮同位素(1δ3C和1δ5N)的变化进行了研究,结果表明:北极楚科奇海域沉积物中的总糖与有机碳为明显的正相关关系,说明糖类是有机碳重要的组成部分;表层沉积物中TOC/TN平均值为9.273,1δ3C和1δ5N的平均值分别为-21.61‰和7.1‰,显示出表层沉积物中糖类物质以海洋藻类来源为主、混入部分陆源物质的分布特征;柱状样品不同深度沉积物中TOC/TN平均值为13.45,也反映出糖类物质为海洋自生和陆源输入共存的分布特征。 相似文献
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环雷州半岛近海表层沉积物有机碳分布及其控制因素分析 总被引：1，自引：0，他引：1
对环雷州半岛近海43个海底表层沉积物的总有机碳(TOC)、总氮(TN)、沉积介质条件(包括沉积物粒度)进行了分析,探讨了沉积物TOC、TN的区域分布特征以及影响有机碳分布的主要因素。结果表明,环雷州半岛近海海域海底表层沉积物有机碳含量在0~0.79%之间,平均值为0.26%。与中国其它近海海域相比,环雷州半岛大部分近海区域海底表层沉积物有机碳含量明显偏低,为有机质贫乏区,仅雷州半岛西南部流沙湾近海海域为TOC相对高值区。总氮含量也不高,在0.011%到0.100%之间,TOC与TN存在较强的正相关性,且平面上TOC与TN分布高度重合,显示氮元素主要以有机化合物形式存在。TOC/TN比值在5.1~14.3之间,表明沉积有机质具有陆源输入和海洋自生来源的混合特征,但以雷州半岛西侧北部及东侧中部海域受陆源有机质输入影响更大。大多数站位海底沉积物粒度构成以粉砂为主、粘土次之,少数站位以砂质沉积为主。沉积物有机碳含量与粘土及粉砂含量呈弱正相关性,与沉积物pH值、Eh值及砂含量呈弱负相关性,这表明海底沉积物有机质丰度受有机质来源输入、海底氧化还原状态和沉积水动力条件(沉积物粒度)等因素综合控制。 相似文献
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长江口及邻近海域现代沉积物中正构烷烃分子组合特征及其对有机碳运移分布的指示 总被引：13，自引：1，他引：12
报道了长江口及邻近海域现代沉积物中正构烷烃的浓度及分布特征,通过因子分析法对正构烷烃来源进行了探讨.结果表明,调查站位正构烷烃主要可归纳为3种类型:陆源输入优势型(单峰群)、陆源和海洋内生混合类型(双峰群)和石油类污染类型(单峰型,不具奇偶优势).长江口邻近站位正构烷烃色谱指标的突变,是长江河口区2种不同水团造成沉积物差异的客观反映.除P4外,研究站位总正构烷烃含量(∑n-Alk)与有机碳总量(TOC)相关性良好,且长江口东南-浙江沿岸软泥区正构烷烃的陆源高等植物组分(TER-Alk)、海洋内生组分(PL-1)、奇偶碳优势指数(CPI)等指标与运移距离呈线形关系.在因子分析显示不同来源的4种正购烷烃中,以陆源烷烃输入比重最大(51.5%),在陆源烷烃中又以东海河流物质贡献最大(49.1%);根据因子负荷差异,推测东海北部沉积有机质可能多数来源于苏北沿岸及老黄河口水下三角洲,冲绳海槽区则可能大部分来源于长江及东海内陆架物质,并探讨了其运移机理. 相似文献
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南海北部4万年以来有机碳和碳酸盐含量变化及古海洋学意义 总被引：5，自引：0，他引：5
南海北部陆坡的17937柱状样上部4万年来有机碳和碳酸盐的含量分布特征显示：有机碳含量总体显示出冰期高、间冰期低的特征,碳酸盐则相反。C／N元素比分布范围和二组分分析说明该站位的有机碳以海洋自生有机碳为主,全新世达80％以上。根据海洋沉积物中总有机碳含量和两类不同来源有机碳所占比例计算得出的海洋自生生物产生的有机碳含量在MIS2时期最高,说明末次冰期海洋生产力提高。冰期冬季风强化,海水混合程度加强,营养物质利用更充分以及陆源输入增多导致营养物质增加。碳酸盐含量主要受陆源物质稀释的影响,为“大西洋型”旋回。碳酸盐旋回在全新世早中期存在低碳酸钙事件,可能与该时期的强降雨冲刷所致陆源稀释作用增强、海水溶解作用增强以及海洋表层生产力的降低等综合作用相关。 相似文献
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南海现代沉积物中正构烷烃碳分子组合特征及其指示意义 总被引：5，自引：0，他引：5
利用1998年6~9月南海海洋环境调查及1987年SO-50中德联合调查中所取得的资料,对南海沉积物中正构烷烃碳分子组合特征进行分析和研究,并将南海与渤海、黄海、东海现代沉积过程中的正构烷烃碳分子组合特征进行对比,结果表明:(1)南海北部沉积物中正构烷烃碳分子分布范围为nC15~nC33,双峰群,居前的低碳数主峰碳为nC19~nC22,居后的高碳数主峰碳为nC27,nC24以后奇碳的优势明显,OEP为2.13,nC23-/nC24 值平均为1.53,沉积物中陆源输入居多;南海南部沉积物中正构烷烃碳分子分布范围为nC15~nC33,呈双峰群,居前的低碳数峰群以nC19~nC23为主峰碳,居后的高碳数峰群以nC27或nC29为主峰碳,OEP为1.58,nC23-/nC24 值平均为2.15,沉积物中海洋生物来源居多。南海沉积物中正构烷烃碳分子为海洋和陆源两种有机质来源。(2)南海南部处于典型热带海洋环境,生物生产力较高,大量硅质、钙质生物在海域繁殖,生物效应降低了陆源物质的丰度。物源效应和生物效应的差异是南海南、北部现代沉积物的碳分子组合分布变化的主要原因。(3)南海现代沉积物各站位沉积物中正构烷烃的P r/Ph值基本小于1,说明沉积物沉积时为缺氧还原的沉积环境,但局部海域沉积环境具有较强的氧化性,沉积物在沉积过程中一定程度上受到涌升的南极底层水的影响。(4)南海与东海、黄海、渤海不同海域沉积物中正构烷烃碳分子组合特征对比可知,各海域沉积物均显示出物源效应。 相似文献
8.
渤海湾和胶州湾表层沉积物中甾醇的分布和来源 总被引：4，自引：0，他引：4
测定了渤海湾和胶州湾22个表层沉积物样品中甾醇类化合物的含量,分析了其分布特征和来源.研究表明,所测定的8种甾醇类化合物在两海区表层沉积物中的含量和分布具有很大的区域差异,其含量为0～4.303 μg/g,渤海湾甾醇总含量为0.287～18.579μg/g,高于胶州湾0.084～10.584 μg/g.8种化合物中只有谷甾醇在全部样品中检出,而粪便甾醇仅存在于受人类活动影响较大和有生活污水输入的近岸区域.而代表陆源高等植物来源的特征甾醇化合物豆甾醇和谷甾醇则在河口区表层沉积物分布较高.另外,根据表层沉积物中不同甾醇化合物的组成、含量和分布特征,可以很好地指示河流输入以及大量生活废水的排放对近岸海区的污染状况,从而可以作为近岸环境污染监测和评价的重要指标. 相似文献
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南海西南次海盆是南海海盆中的一个重要构造单元,了解其沉积物的地球化学信息对于认识南海沉积环境至关重要。采用色谱质谱(GC-MS)方法对南海西南次海盆B3C和C7两个站位沉积柱中的酸类化合物进行研究,结果表明:(1)南海西南次海盆B3C和C7站位柱状沉积物中的正构脂肪酸呈偶奇优势分布,普遍以n-C_(16)和n-C_(18)为主;沉积物主要来源于浮游生物、藻类、细菌等,并有陆源高等植物的贡献。(2)B3C和B7沉积柱中酸类化合物来源主要以海源为主,总正构脂肪酸含量以及陆源优势正构脂肪酸(n-C_(24)、n-C_(26)、n-C_(28))、海源优势正构脂肪酸(n-C_(12)、n-C_(14)、n-C_(16))含量在垂向上分布较为稳定,变化波动小,表明该地区的大部分时期沉积环境较为稳定。(3)总脂肪酸(TFA)和TFA/TOC均表明该区域有机物积累普遍较低,且该处沉积区域处于非透光区和非热液区。 相似文献
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渤海表层沉积物中有机碳的分布和来源 总被引：3，自引：0，他引：3
大河影响下的陆架边缘海沉积有机碳的分布和来源是全球碳循环研究的重要内容。本研究于2012年5月采集了渤海海域的29个表层沉积物样品,分析了粒度组成、总有机碳(TOC)、总氮(TN)、木质素含量和稳定碳同位素丰度(δ13C)等参数,结合基于蒙特卡洛模拟的三端元混合模型,定量研究了沉积物中有机碳的分布和来源情况,并讨论了其影响因素。结果表明,研究区域表层沉积物中TOC含量为0.19%~0.81%,渤海中部泥质区站位(大于0.65%)明显高于其周围砂质区域站位(小于0.40%);TOC与黏土含量也有显著的正相关性,说明细颗粒沉积物容易富集有机碳。沉积有机碳的δ13C范围为-23.7‰~-21.8‰,显示沉积有机碳是海源和陆源有机碳的混合输入。木质素参数,如C/V、S/V和LPVI的数值范围显示研究区域表层沉积物中木质素主要来源于被子植物草本组织与木本组织的混合,同时有少量裸子植物的贡献。基于蒙特卡洛模拟的三端元混合模型显示研究区域沉积物中有机碳主要来源于海洋浮游植物,平均为64%,陆源有机碳中来自土壤的贡献最高(平均为27%),C3维管植物的贡献较少(平均为9%)。海洋浮游植物有机碳主要分布在渤海中部泥质区及离岸较远的区域,而土壤有机碳和C3维管植物有机碳则主要沉积在河口附近及近岸区,并可以离岸输运到较远的地方。 相似文献
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This study examined the concentrations of polycyclic aromatic hydrocarbons (PAHs) in surface sediments collected in July 2004 from eight stations in the Zhelin Bay, one of the most important bays for large-scale mariculture in Guangdong Province. Thirteen individual parent PAH compounds were identified using high performance liquid chromatography with UV detection. The overall average concentration of total PAHs was 477.0 ng/g, ranging from 146.1 to 928.8 ng/g. Low molecular mass PAHs with two to three rings (e.g., acenaphthene) were dominant in each sample. The PAH concentration varied among sampling stations, with the highest concentration observed at bay outlets and the lowest found at stations outside the bay. Ratios of low to high molecular mass PAHs and fluoranthene to pyrene were used to determine the origin of PAHs, and results indicated mainly petroleum-derived contamination. Compared with other bays and harbors around the world, the total concentrations of PAHs in surface sediments at the Zhelin Bay are moderate, but this does not exclude the possibility of potential impact on human consumers because some strong carcinogenic PAHs with high molecular mass were found at the station with a nearby caged-fish and oyster farm. Long-term monitoring of PAH contamination in the Zhelin Bay is recommended to reduce the potential toxicological effects on aquatic organisms and humans. 相似文献
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In this study, we examined the distribution of polycyclic aromatic hydrocarbons (PAHs) in a contaminated coastal area and the characteristics of the natural organic matter in tandem. We present a detailed study of PAH concentration, distribution, and organic matter characteristics of three core samples from Pensacola Bay, Florida. Solid-state 13C Nuclear Magnetic Resonance (NMR), pyrolysis gas chromatography coupled with mass spectrometry (GC-MS), and tetramethyl ammonium hydroxide (TMAH) thermochemolysis GC-MS were applied to obtain structural details about the sedimentary organic matter. Elemental compositions (carbon and nitrogen) and estimates of black carbon contents are also reported. These coastal sediments were found to contain more PAHs in the upper 15 cm layers than in the bottom 15-25 cm samples. The samples that contained the most PAHs also contained the least amount of aromatic carbon and contained a significant amount of paraffinic carbon. Lignin-derived pyrolysis and TMAH thermochemolysis products were abundant and generally higher in all of the samples in comparison to those reported for modern coastal sediments, indicating a large flux of terrestrial carbon. The black carbon contents were found to range from 4.3% to 6.8%, which are significantly lower than other reports of black carbon in sediments, which represent as much as 65% of the total organic carbon content. The low black carbon content suggests that this type of refractory carbon may not be as responsible for regulating PAH distribution as indicated by other researchers. 相似文献
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研究了台州湾海域海水和表层沉积物中15种多环芳烃(PAHs)的浓度水平,评价了表层沉积物对多环芳烃的富集规律,探讨其可能来源.结果表明,表层沉积物中PAHs的浓度范围为85.4 ～ 167.6 ng/g,平均值为138.62 ng/g,总多环芳烃的最大值是椒江码头.表层沉积物中二环、三环、四环、五环和六环多环芳烃占总多环芳烃的百分含量平均值分别为7.8 %,42.1 %, 33.3 %, 9.6 %和 7.2 %,三环多环芳烃的含量最高;表层沉积物对多环芳烃的富集系数为532.7 ～ 1068.9,平均值为807.5,单组分菲的富集系数最高为122.7,最小的是苯并(a)芘为2.7;台州湾表层沉积物中的多环芳烃主要来源于燃煤污染,部分来源于石油烃类物质的直接污染. 相似文献
14.
Hydrocarbons in the sediments of Port Valdez,Alaska: Consequences of five years' permitted discharge
David G. Shaw Thomas E. Hogan Douglas J. McIntosh 《Estuarine, Coastal and Shelf Science》1985,21(2):131-144
Hydrocarbons have been investigated in the sediments of Port Valdez, Alaska after three to five years of oil terminal operation with a routine daily discharge of 170 kg of petroleum residue in an otherwise undeveloped area. Surficial benthic sediments (0–5 cm) and core segments down to 30 cm have been analyzed. Information about total hydrocarbons, unresolved complex mixture, normal alkanes, pristane, phytane, hopanes and polycyclic aromatic hydrocarbons indicates that petroleum, biogenic hydrocarbons, and combustion-derived aromatic hydrocarbons are present in sediments around the terminal at concentrations up to 218 μg g?1 dry sediment. The vertical, horizontal and temporal distributions of anthropogenic hydrocarbons indicate that most of the sedimentary hydrocarbon accumulation has occurred within 1 km of the terminal. A simple calculation suggests that less than 3% of the total oil discharged during routine operations of the terminal has entered the sediments of Port Valdez. For comparison sediment hydrocarbon accumulation associated with a nearby small boat harbor was also examined. 相似文献
15.
The paper presents research results on the concentrations and compositions of aliphatic and polycyclic aromatic hydrocarbons in the surface layer of bottom sediments in the Northwestern Caspian Sea (2014) and compares them to data for sediments of the Middle and Southern Caspian (2012–2013). The seepage of hydrocarbons out of the sediment mass, resulting in abnormally high concentrations of aliphatic hydrocarbons per dry weight (up to 468 μg/g), as well as within the Corg composition (up to 35.2%), is considered the main source of hydrocarbons in sediments in the surveyed area of the Northern Caspian. This is also confirmed by the absence of any correlation between the hydrocarbon and Corg distributions, as well as by the transformed oil composition of high-molecular alkanes. The distribution of markers within polycyclic aromatic hydrocarbons points to a mixed genesis—petrogenic and pyrogenic—with prevalence of the latter. Unlike the shallow-water northern part of the Caspian Sea, the content and composition of hydrocarbons in deep-seated sediments are affected by facial conditions of sedimentation and by matter exchange at the water–bottom interface. Therefore, despite high Corg concentrations (up to 9.9%), sediments in deep-water depressions are characterized by a quite low concentration of aliphatic hydrocarbons (52 μg/g on average; 0.2% of Corg) with prevailing natural allochthonous alkanes. 相似文献
16.
Abbondanzi F Campisi T Focanti M Guerra R Iacondini A 《Marine environmental research》2005,59(5):419-434
A study was conducted to determine polycyclic aromatic hydrocarbons (PAHs) distribution and microbial population changes in brackish sediments from an Italian lagoon included in the Ramsar List of Wetlands of International Importance. The presence and level of PAH-degrading bacteria were estimated by the most probable number (MPN) enumeration technique, whereas degradation capability towards target compounds was checked against loss of spiked PAHs (Phenanthrene, Anthracene and Fluoranthene) in MPN tubes after incubation in optimal conditions. Chemical analyses and microbiological counts suggested a potential for PAHs biodegradation by natural occurring populations of sediment microorganisms, thus indicating an "optimal range" in sediment PAHs concentrations, outside of which the natural selection of the indigenous microflora did not occur. The MPN procedure here described, provided an effective and reliable way to simultaneously determine microbial population densities and subsequent confirmation of the biodegradation capability of sediment indigenous microflora when exposed to laboratory and environmental concentrations of PAHs. 相似文献
17.
大亚湾海域多环芳烃和有机氯农药的高分辨率沉积记录 总被引：6，自引：0，他引：6
以GC／ECD和GC／MS内标法分析测定了大亚湾沉积物柱样（DYW03—8）中多环芳烃（PAHs）和有机氯农药（0CPs）的含量，结合^210Pb定年，重建了该海域近50年来PAHs和OCPs的污染历史，并对其可能的来源和输入途径进行了探讨。结果表明，近50年来该海域沉积物中PAHs和OCPs的含量总体上均呈上升趋势，且一般都在上世纪90年代以后这种上升变得更加明显；PAHs主要来源于化石燃料的不完全燃烧，即热成因，并可能主要通过大气颗粒物沉降以及工业和生活污水的直接排放等途径进入水体沉积物中；HCHs和DDTs的组成特征及其变化趋势揭示，该区可能曾大量使用过林丹（γ-HCHs）作为杀虫剂，近15年来随着该地区各种经济开发活动的加强，残留在土壤中的这些农药组分更多地随地表径流进入到水体沉积物中。同时，DDTs类农药也可能仍存在新的输入源，但这种输入的强度在近几年似乎有所减弱。 相似文献
18.
Yunker MB Lachmuth CL Cretney WJ Fowler BR Dangerfield N White L Ross PS 《Marine environmental research》2011,72(3):105-126
The question of polycyclic aromatic hydrocarbon (PAH) bioavailability and its relationship to specific PAH sources with different PAH binding characteristics is an important one, because bioavailability drives PAH accumulation in biota and ultimately the biochemical responses to the PAH contaminants. The industrial harbour at Kitimat (British Columbia, Canada) provides an ideal location to study the bioavailability and bioaccumulation of sediment hydrocarbons to low trophic level biota. Samples of soft shell clams (Mya arenaria) and intertidal sediment collected from multiple sites over six years at various distances from an aluminium smelter and a pulp and paper mill were analysed for 106 PAHs, plant diterpenes and other aromatic fraction hydrocarbons. Interpretation using PAH source ratios and multivariate data analysis reveals six principal hydrocarbon sources: PAHs in coke, pitch and emissions from anode combustion from the aluminium smelter, vascular plant terpenes and aromatised terpenes from the pulp and paper mill, petroleum PAHs from shipping and other anthropogenic activities and PAHs from natural plant detritus. Harbour sediments predominantly contain either pitch or pyrogenic PAHs from the smelter, while clams predominantly contain plant derived PAHs and diterpenes from the adjacent pulp mill. PAHs from the smelter have low bioavailability to clams (Biota-Sediment Accumulation Factors; BSAFs <1 for pitch and coke; <10 for anode combustion, decreasing to ∼0.1 for the mass 300 and 302 PAHs), possibly due to binding to pitch or soot carbon matrices. Decreases in PAH isomer ratios between sediments and clams likely reflect a combination of variation in uptake kinetics of petroleum PAHs and compound specific metabolism, with the importance of petroleum PAHs decreasing with increasing molecular weight. Plant derived compounds exhibit little natural bioaccumulation at reference sites, but unsaturated and aromatised diterpenes released from resins by industrial pulping processes are readily accumulated by the clams (BSAFs >500). Thus while most of the smelter associated PAHs in sediments may not be bioavailable to benthic organisms, the plant terpenes (including retene, totarol, ferruginol, manool, dehydroabietane and other plant terpenes that form the chemical defence mechanism of conifers) released by pulp mills are bioavailable and possess demonstrated toxic properties. The large scale release of plant terpenes by some of the many pulp mills located in British Columbia and elsewhere represents a largely undocumented risk to aquatic biota. 相似文献
19.
Gilbert Mille Yan Yu Chen Gérard Giusti Henri Dou Evelyne Vacelet Marie-Reine Plante-Cuny 《Marine environmental research》1984,11(3):213-232
The evolution of hydrocarbons in sediments was studied from 1978 to 1980 at eight stations in the Ile Grande marshes (Brittany) polluted by the Amoco Cadiz oil spill. Generally, in 1980 (except for one heavily polluted site) the amounts of hydrocarbons were found to be far less important than in 1978 and sometimes biogenic hydrocarbons were found. In the superficial layer of the sediments biodegradation processes were generally important with the preferential degradation of n-alkanes. On the other hand, aromatic hydrocarbons seem not to have been altered after three years. Degradation of percolated hydrocarbons proceeds more slowly than in the surface layer. The number of degrading bacteria decreases when n-alkanes disappear. 相似文献
