Arctic freshwater ostracods from modern periglacial environments in the Lena River Delta (Siberian Arctic, Russia): geochemical applications for palaeoenvironmental reconstructions
Arctic freshwater ostracods from modern periglacial environments in the Lena River Delta (Siberian Arctic, Russia): geochemical applications for palaeoenvironmental reconstructions
复制标题
来自勒拿河三角洲（俄罗斯西伯利亚北极）现代冰缘环境的北极淡水介形类：古环境重建的地球化学应用
DOI：
10.1007/s10933-007-9122-1
复制
发表时间：
2008
影响因子：
2.1
通讯作者：
A. Mackensen
中科院分区：
文献类型：
--
作者：
S. Wetterich;Lutz Schirrmeister;H. Meyer;F. Viehberg;A. Mackensen
本研究的目的是描述西伯利亚北极淡水栖息地的介形虫，以估计当今环境背景与介形虫方解石地球化学性质之间的关系。重点研究了环境沃茨和介形虫方解石中的元素比值（Mg/Ca，Sr/Ca）和稳定同位素组成（δ 18 O，δ 13 C）。最常见的种类是Fabaeformiscandona pedata和F. harmssynii在所有研究的沃茨中频率最高。F的平均分配系数D（Sr）。雌、雄鼠的平均值分别为0.33 ± 0.06（1σ）和0.32 ± 0.06（1σ）。δ 18 O值与δ 18 O值的关系接近1：1，δ 18 O值向重δ 18 O值的平均偏移Δmean = 2.2‰ ± 0.5（1σ）。与周围沃茨相比，这种变化不取决于δ 18 O水，而是由代谢（生命）和温度影响引起的。温度依赖性反映在这种转变的变化。对F. pedata一个重要的影响相比，无机方解石在平衡被量化为1.4‰。研究结果对多年冻土层介形类化石地球化学资料的古环境解释具有重要意义。
The aim of this study is to describe ostracods from freshwater habitats in the Siberian Arctic in order to estimate the present-day relationships between the environmental setting and the geochemical properties of ostracod calcite. A special focus is on the element ratios (Mg/Ca, Sr/Ca), and the stable isotope composition (δ18O, δ13C), in both ambient waters and ostracod calcite. The most common species are Fabaeformiscandona pedata and F. harmsworthi with the highest frequency in all studied waters. Average partition coefficients D(Sr) of F. pedata are 0.33 ± 0.06 (1σ) in females, and 0.32 ± 0.06 (1σ) in males. A near 1:1 relationship of δ18O was found, with a mean shift of Δmean = 2.2‰ ± 0.5 (1σ) to heavier values in ostracod calcite of F. pedata as compared to ambient waters. The shift is not dependent on δ18Owater, and is caused by metabolic (vital) and temperature effects. Temperature-dependence is reflected in the variations of this shift. For ostracod calcite of F. pedata a vital effect as compared to inorganic calcite in equilibrium was quantified with 1.4‰. Results of this study are valuable for the palaeoenvironmental interpretation of geochemical data of fossil ostracods from permafrost deposits.