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We performed a comparison analysis of the variations .in Mercury ( Hg) concentrations and the precipitation proxies ( e. g. , 18 O values and 10 Be concentrations) in the Dome C ice core. The results showed that there were significant correlations between Hg and δ 10O values, 10Be concentrations, indicating that the accumulation rate in Dome C is one of the key factors controlling the variations of Hg concentrations in the past 34 ,000 years, and implying that Hg concentrations in ice core can be used as another reliable proxy of precipitation rate in Antarctica. Based upon the high-resolution δ 18O values, we estimated the variations in mercury deposition flux to Antarctica over the past 34,000 years. The highest mercury deposition flux is about 3. 80 pg cm-2 yr-1 during the Last Glacial Maxium (LGM) as high as 3. 5 times of the mercury deposition flux ( about 1. 08 pg cm -2 yr -1) in Holocene due to the fluctuations in natural mercury emissions such as the oceanic biological emissions. 相似文献
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The concentrations of organic carbon(OC)and elemental carbon(EC)in total suspended particle(TSP)were investigated at Ny-Alesund,Svalbard in atwo-week campaign.The levels of OC and EC are 0.86±0.27μgm~(-3)(mean±standard deviation)and 0.19±0.10μgm~(-3),respectively.Back trajectory analy-sis of air masses arriving at Ny-lesund reveals that long-range transport of pol-luted air play insignificant role in OC and EC levels,to which the potential influ-ence of the local contamination were ascribed.The average OC/EC ratio is 5.41,suggesting the presence of the secondary organic aerosols.The estimated second-ary organic carbon(SOC)in TSP is 0.59μg/m~3,accounting for 64% of the totalorganic carbon. 相似文献
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Preliminary investigation of mercury in bone tissues of skua and penguin in Antarctica using AFS and Synchrotron Radiation X-ray Fluorescence(SR-XRF) 
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下载免费PDF全文 <正> Mercury(Hg)was investigated in bone tissues of skua(Catharacta mac-cormick)and penguin(Pygoscelis adeliae)collected in the maritime Antarctic usingatomic fluorescence spectrometry(AFS)and synchrotron radiation X-ray fluorescence(SR-XRF)method.The total levels of mercury in bone tissues of penguin and skuaare much lower than those in other organs(e.g.,kidney,liver).The toxic effects ofmercury in bone tissues of seabirds in polar region are not known.We have used SR-XRF method to map the distribution of trace levels of mercury in bones.The levels ofmercury are found to be enriched somewhere near the periosteal surface and/or endos-teal surface.The distribution of mercury shows strongly correlation with that of someessential elements and probably poses negative effect on the bone metabolism inferringfrom the relationship of mercury with the other elements.These studies represent afirst step toward understanding the toxic effects of mercury on bone of polar animals bysuggesting the possible microscopic investigation. 相似文献
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Synchrotron radiation X-ray fluorescence （SR-XRF） approach was applied to analyzing of Chinstrap penguin （ Pygoscelis Antarctica） cortical bone. The method enabled the in situ determination of Ca and P concentrations and the Ca/P ratio in cortical bone. The preliminary results show that ： （ 1 ） there is the bone site-related difference for Ca and P concentrations. The mean values for the investigated parameters （ on a dry-weight basis） are： 30.7% （Ca） and 14.9% （P） for the femoral cortical bone, 21.4% （Ca） and 11.5% （P） for wing cortical bone. （2） The variation for the Ca/P ratio in cortical bone is lower than those for Ca and P separately. This is in agreement with the previous report that the specificity of the Ca/P ratio is better than that of Ca and P concentrations and is more reliable for the diagnosis of bone disorders. The authors suggest that further studies be conducted to establish norreal values of Ca, P and Ca/P ratio for polar animals and provide a basis for the diagnosis of bone disorders. 相似文献
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本文对采自东南极拉斯曼丘陵中山站区的莫愁湖沉积物的元素、氨基酸和Sr同位素组成进行了详细的地球化学分析。结果表明莫愁湖沉积物中Zn、Cu、F、S、P、Se等六种元素具有共同的物质来源,其标型组合特征很可能揭示了莫愁湖沉积物在历史时期曾受到过企鹅等海鸟粪的影响,沉积物中酸溶相Sr同位素组成则确认了海洋源Sr的生物地球化学转移过程。酸溶相87Sr/86Sr值和研究区的新鲜海鸟粪酸溶相Sr同位素组成基本一致,都非常接近于海洋来源锶同位素组成(87Sr/86Sr=0.7092),并且沉积物中的生物元素Zn、Cu、F、S、P、Se含量和酸溶相Sr浓度具有非常高的统计相关性。酸溶相的87Sr/86Sr比值和反映湖泊中藻类等生物自然生成量的氨基酸含量表现出明显的负相关关系,进一步揭示了莫愁湖沉积物在历史时期曾受到企鹅等海鸟活动的影响。上述研究结果为更深入地研究该地区的生态、气候和环境的演变历史及其相互作用提供了有价值的参考资料。 相似文献
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应用计算机数字影像学原理,建立了对磷质胶结微细纹层研究的数值化方法,研究了西沙东岛珊瑚砂砾屑灰岩磷质胶结物的胶结结构和微纹层特征,定量地刻画了微条纹的宽度和颜色变化信息。东岛珊瑚砂砾屑灰岩磷质胶结物的形成以沉淀胶结为主,不同时期形成的胶结物微条纹系列,由于受到气候、生态因素的影响,具有不同的宽度、明暗度组合;对3个层次磷质胶结物的分析表明,在2900~5700 aBP西沙群岛东岛存在至少3次鸟类和植物的繁盛期;不同时期微纹层的气候、生态记录对比发现,相对稳定的气候条件有利于岛屿海鸟数量的扩大;提供了一种新的方法来探索岛屿鸟粪磷质胶结物的结构和生态环境意义。 相似文献
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本文统计分析了南极DomeC冰芯中汞含量和降水指征参数δ1 8O值、1 0 Be浓度的关系 ,发现冰芯中Hg含量和δ1 8O值、1 0 Be浓度变化一致 ,表明DomeC冰芯汞含量受到冰雪积累率的影响 ,而且三者变化的高度同步性可能说明其原始驱动力也是一致的 ,从而冰芯中Hg含量可以和1 0 Be浓度一样作为冰雪积累率估算的替代性指标。此外 ,利用δ1 8O数据 ,系统估算了 340 0 0年以来南极汞沉降通量的变化。结果表明 ,DomeC冰芯汞沉降通量在末次冰盛期 (LGM)最高 ,为 3.80pgcm- 2 a- 1 ,约是全新世汞沉降通量 ( 1 .0 8pgcm- 2 a- 1 )的 3.5倍 ,该变化可能主要受到汞的自然排放量影响。 相似文献
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本文应用同步辐射加速器X荧光(SR-XRF)分析技术并结合电感耦合等离子体质谱(ICP-MS)方法对中国首次北极考察采集的气溶胶样品进行了定量分析。SR-XRF方法对6种元素的分辨率分别为1.1ng/cm2(Ca)、39.7ng/cm2(V)、17.6ng/cm2(Fe)、2.3ng/cm2(Ni)、1.8ng/cm2(Zn)、6.4ng/cm2(Pb)。6种元素的浓度分别为117.3(ng/m3,Ca)、16.5(ng/m3,V)、19.3(ng/m3,Fe)、3.4(ng/m3,Ni)、4.5(ng/m3,Zn)、1.4(ng/m3,Pb)。该结果与文献报道的相应海区夏季气溶胶化学成分含量具有可比性。由于SR-XRF方法灵敏度高,属于无损分析,在极地气溶胶研究中具有广泛的应用前景。 相似文献