Palaeobotanical evidence for warm summers in the East Siberian Arctic during the last cold stage |
| |
| Authors: | Frank Kienast Lutz Schirrmeister Christine Siegert Pavel Tarasov |
| |
| Institution: | aAlfred Wegener Institute for Polar and Marine Research, Telegrafenberg A43, 14473 Potsdam, Germany;bFree University Berlin, Institute of Geological Sciences, Palaeontological Branch, Malteserstr. 74-100, Building D, 12249 Berlin, Germany |
| |
| Abstract: | Plant macrofossils from the “Mamontovy Khayata” permafrost sequence (71°60′N, 129°25′E) on the Bykovsky Peninsula reflect climate and plant biodiversity in west Beringia during the last cold stage. 70 AMS and 20 conventional 14C dates suggest sediment accumulation between about 60,000 and 7500 14C yr B.P. The plant remains prove that during the last cold-stage arctic species (Minuartia arctica, Draba spp., Kobresia myosuroides) coexisted with aquatic (Potamogeton vaginatus, Callitriche hermaphroditica), littoral (Ranunculus reptans, Rumex maritimus), meadow (Hordeum brevisubulatum, Puccinellia tenuiflora) and steppe taxa (Alyssum obovatum, Silene repens, Koeleria cristata, Linum perenne). The reconstructed vegetation composition is similar to modern vegetation mosaics in central and northeast Yakutian relict steppe areas. Thus, productive meadow and steppe communities played an important role in the Siberian Arctic vegetation during the late Pleistocene and could have served as food resource for large populations of herbivores. The floristic composition reflects an extremely continental, arid climate with winters colder and summers distinctly warmer than at present. Holocene macrofossil assemblages indicate a successive paludification possibly connected with marine transgression, increased oceanic influence and atmospheric humidity. Although some steppe taxa were still present in the early Holocene, they disappeared completely before  2900 14C yr B.P. |
| |
| Keywords: | Plant macrofossils Arctic Siberia Palaeoclimate Late Pleistocene Vegetation |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
