Carbon analysis of surface sediments from the Laptev Se@en

During the past six years organic geochemical, micropaleontological, and sedimentological investigations were carried out within the framework of the multidisciplinary bilateral German-Russian research project ''System Laptev Sea'' and detailed biological investigations within the project ''German-Russian Investigations of the Marginal Seas of the Eurasian Arctic'', In order to understand the Laptev Sea ecosystem and to obtain information about sources and fate of organic carbon, the distribution of phyto- and zooplankton, diatoms, chlorophyll a benthic macrofauna, palynomorphs, grain size, total organic carbon, d13Corg and biomarkers (n-alkanes, fatty acids) were determined. In general, the influence of the major rivers draining into the Laptev Sea, is reflected in the water column as well as in the surface sediments. In both habitats three ecological provinces can be distinguished, i.e., the southeastern Laptev Sea, the central Laptev Sea, and the northern Laptev Sea. Additionally, clear differences between the western and the eastern Laptev Sea occur. The comparison of the different data sets of the water column and the surface sediments provide information about organic carbon sources and pathways in the Laptev Sea shelf and continental slope area.过去六年间，研究团队依托德俄双边多学科联合研究项目「拉普捷夫海系统（System Laptev Sea）」开展了有机地球化学、微古生物学与沉积学相关研究；同时在「德俄欧亚北极边缘海调查（German-Russian Investigations of the Marginal Seas of the Eurasian Arctic）」项目框架内完成了精细化生物学调查。为解析拉普捷夫海生态系统，并获取有机碳来源与归宿相关信息，本数据集测定了浮游植物、浮游动物、硅藻、叶绿素a(chlorophyll a)、底栖大型生物(benthic macrofauna)、孢粉类群(palynomorphs)、沉积物粒度(grain size)、总有机碳(total organic carbon)、有机碳同位素δ¹³Corg(d13Corg)以及生物标志物(biomarkers，涵盖正构烷烃(n-alkanes)与脂肪酸(fatty acids))的分布特征。总体而言，注入拉普捷夫海的主要河流的影响，在水体柱(water column)与表层沉积物(surface sediments)中均有体现。在这两类生境中，均可划分出三个生态分区，即拉普捷夫海东南部、中部与北部海域；此外，拉普捷夫海东西部海域亦存在显著差异。通过对比水体柱与表层沉积物的多组数据集，可获取拉普捷夫海陆架与大陆坡区域内有机碳来源及运移路径相关信息。