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  1. Book ; Online: Paleoclimate investiations on sediment core PG1984 from Lake Sysy-Kyuele, northern Siberia, supplementary data to: Biskaborn, Boris Kolumban; Herzschuh, Ulrike; Bolshiyanov, Dimitry Yu; Savelieva, Larissa A; Diekmann, Bernhard (2012): Environmental variability in northeastern Siberia during the last ~13300 yr inferred from lake diatoms and sediment-geochemical parameters. Palaeogeography, Palaeoclimatology, Palaeoecology, 329-330, 22-36

    Biskaborn, Boris Kolumban / Bolshiyanov, Dimitry Yu / Diekmann, Bernhard / Herzschuh, Ulrike / Savelieva, Larissa A

    2012  

    Abstract: In northeastern Siberia, Russia, a 1.2 m sediment core was retrieved and radiocarbon dated from a small and shallow lake located at the western side of the lower Lena River (N 69°24', E 123°50', 81 m a.s.l.). The objective of this paper is to reconstruct ...

    Abstract In northeastern Siberia, Russia, a 1.2 m sediment core was retrieved and radiocarbon dated from a small and shallow lake located at the western side of the lower Lena River (N 69°24', E 123°50', 81 m a.s.l.). The objective of this paper is to reconstruct the palaeoenvironmental variability and to infer major palaeoclimate trends that have occurred since ~ 13.3 cal. kyrs BP. We analysed the diatom assemblages, sedimentology (grain size, total organic carbon (TOC), total nitrogen (TN)), and the elemental and mineralogical composition using X-ray fluorescence (XRF) and X-ray diffractometry (XRD) of the sediment core. Our results show parallel changes in the diatom species composition and sediment characteristics. Enhanced minerogenic sediment input and the occurrence of pyrite is indicative of a cold period between ~ 12.7-11.6 cal. kyrs BP. The diatom data enable a qualitative inference about the local ecological conditions to be made, and reveal an oligotrophic lake system with alkaline and cold conditions during the earliest Holocene. Moderately warmer climates are inferred for the period from ~ 9.1 to 5.7 cal. kyrs BP. The major shift in the diatom assemblage, from dominance of small benthic fragilarioid taxa to a more complex diatom flora with an influx of several achnanthoid and naviculoid diatom species, occurred after a transitional period of about 1400 years (7.1 to 5.7 cal. kyrs BP) at ~ 5.7 cal. kyrs BP, indicating a circumneutral and warmer hydrological regime during the Holocene thermal maximum (HTM). Diatom valve concentrations declined starting ~ 2.8 cal. kyrs BP, but have been rising again since less than or equalt to 600 cal. years BP. This has occurred in parallel to the increased presence of acidophilous diatom taxa (e.g. Eunotia spp.) and decreased presence of small benthic fragilarioid species in the most recent sediments, which is interpreted as the result of neoglacial cooling and subsequent recent climate warming. Our findings are compared to other lake-inferred climate reconstructions along the Lena River. We conclude that the timing and spatial variability of the HTM in the lower Lena River area reveal a temporal delay from north to south.
    Language English
    Dates of publication 2012-9999
    Size Online-Ressource
    Publisher PANGAEA - Data Publisher for Earth & Environmental Science
    Publishing place Bremen/Bremerhaven
    Document type Book ; Online
    Note This dataset is supplement to doi:10.1016/j.palaeo.2012.02.003
    DOI 10.1594/PANGAEA.776490
    Database Library catalogue of the German National Library of Science and Technology (TIB), Hannover

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  2. Book ; Online: Tab. 2: Pollen trap results 1998/1999 from Lena Delta, supplementary data to: Savelieva, Larissa A; Dorozhkina, Marina V; Pavlova, Elena Yu (2002): Modern annual deposition and aerial pollen transport in the Lena Delta. Polarforschung, 70, 115-122

    Savelieva, Larissa A / Dorozhkina, Marina V / Pavlova, Elena Yu

    2011  

    Abstract: Studies of the annual pollen and spore deposition in different areas of the Lena Delta were undertaken for the first time in the Asian sector of the Arctic during the Russian-German "LENA 98" and "LENA 99" expeditions in the framework of the ... ...

    Abstract Studies of the annual pollen and spore deposition in different areas of the Lena Delta were undertaken for the first time in the Asian sector of the Arctic during the Russian-German "LENA 98" and "LENA 99" expeditions in the framework of the International "Laptev Sea System-2000" Project. To achieve this objective, three spore-pollen traps were set up along the meridional delta profile in accordance with the European Pollen Monitoring Programme for the period July 1998 to August 1999. A comparison between the results of spore-pollen analysis of the contents of traps and the surrounding vegetation was performed. The results confirmed the current spore-pollen spectra are comprised both of pollen and spores of the local plants and of long-distance pollen and spores. The dependence of the long-distance pollen deposition on the character of the wind regime of the region was established. The prevailing southerly and southeasterly wind direction determines the main pollen influx of tree species from the areas of their growth south of the delta. The features of the morphological structure and fossilization of pollen and the features of the productive capability and plant growing conditions are of large significance in the pollen transfer and deposition.
    Language English
    Dates of publication 2011-9999
    Size Online-Ressource
    Publisher PANGAEA - Publishing Network for Geoscientific & Environmental Data
    Publishing place Bremen/Bremerhaven
    Document type Book ; Online
    Note This dataset is supplement to hdl:10013/epic.29864.d001
    DOI 10.1594/PANGAEA.757994
    Database Library catalogue of the German National Library of Science and Technology (TIB), Hannover

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  3. Article ; Online: Siberian larch forests and the ion content of thaw lakes form a geochemically functional entity.

    Herzschuh, Ulrike / Pestryakova, Luidmila A / Savelieva, Larissa A / Heinecke, Liv / Böhmer, Thomas / Biskaborn, Boris K / Andreev, Andrei / Ramisch, Arne / Shinneman, Avery L C / Birks, H John B

    Nature communications

    2013  Volume 4, Page(s) 2408

    Abstract: Siberian larch forests growing on shallow permafrost soils have not, until now, been considered to be controlling the abiotic and biotic characteristics of the vast number of thaw-lake ecosystems. Here we show, using four independent data sets (a modern ... ...

    Abstract Siberian larch forests growing on shallow permafrost soils have not, until now, been considered to be controlling the abiotic and biotic characteristics of the vast number of thaw-lake ecosystems. Here we show, using four independent data sets (a modern data set from 201 lakes from the tundra to taiga, and three lake-core records), that lake-water geochemistry in Yakutia is highly correlated with vegetation. Alkalinity increases with catchment forest density. We postulate that in this arid area, higher evapotranspiration in larch forests compared with that in the tundra vegetation leads to local salt accumulation in soils. Solutes are transported to nearby thaw lakes during rain events and snow melt, but are not fully transported into rivers, because there is no continuous groundwater flow within permafrost soils. This implies that potentially large shifts in the chemical characteristics of aquatic ecosystems to known warming are absent because of the slow response of catchment forests to climate change.
    MeSH term(s) Ecosystem ; Geography ; Geologic Sediments ; Ions/analysis ; Lakes/chemistry ; Larix/physiology ; Models, Theoretical ; Siberia ; Time Factors ; Trees/physiology
    Chemical Substances Ions
    Language English
    Publishing date 2013
    Publishing country England
    Document type Journal Article
    ISSN 2041-1723
    ISSN (online) 2041-1723
    DOI 10.1038/ncomms3408
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Book ; Online: Pollen and spore deposition in different areas of the Lena Delta, supplementary data to: Savelieva, Larissa A; Dorozhkina, Marina V; Pavlova, Elena Yu (2002): Modern annual deposition and aerial pollen transport in the Lena Delta. Polarforschung, 70, 115-122

    Savelieva, Larissa A / Dorozhkina, Marina V / Pavlova, Elena Yu

    2002  

    Abstract: Studies of the annual pollen and spore deposition in different areas of the Lena Delta were undertaken for the first time in the Asian sector of the Arctic during the Russian-German ''LENA 98'' and ''LENA 99'' expeditions in the framework of the ... ...

    Abstract Studies of the annual pollen and spore deposition in different areas of the Lena Delta were undertaken for the first time in the Asian sector of the Arctic during the Russian-German ''LENA 98'' and ''LENA 99'' expeditions in the framework of the International ''Laptev Sea System-2000'' Project. To achieve this objective, three spore-pollen traps were set up along the meridional delta profile in accordance with the European Pollen Monitoring Programme for the period July 1998 to August 1999. A comparison between the results of spore-pollen analysis of the contents of traps and the surrounding vegetation was performed. The results confirmed the current spore-pollen spectra are comprised both of pollen and spores of the local plants and of long-distance pollen and spores. The dependence of the long-distance pollen deposition on the character of the wind regime of the region was established. The prevailing southerly and southeasterly wind direction determines the main pollen influx of tree species from the areas of their growth south of the delta. The features of the morphological structure and fossilization of pollen and the features of the productive capability and plant growing conditions are of large significance in the pollen transfer and deposition.
    Language English
    Dates of publication 2002-9999
    Size Online-Ressource
    Publisher PANGAEA - Data Publisher for Earth & Environmental Science
    Publishing place Bremen/Bremerhaven
    Document type Book ; Online
    Note This dataset is supplement to hdl:10013/epic.29864.d001
    DOI 10.1594/PANGAEA.728538
    Database Library catalogue of the German National Library of Science and Technology (TIB), Hannover

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