High resolution palaeo-ecological analysis of an Arctic ice-wedge polygon mire (Kytalyk, NE Siberia)

• Main Author: Teltewskoi, Annette
• Format: Doctoral or Postdoctoral Thesis
• Language: English
• Published: 2020
• Subjects: Moore; Permafrost; Paläoökologie; Vegetation; Modellierung; Fossilisation; Pollen; Fossilien; Geochemie; Arktis; ddc:560; Arctic; Indigirka; Arktis*; Climate change; Ice; permafrost; wedge*; Siberia
• Online Access: https://epub.ub.uni-greifswald.de/frontdoor/index/index/docId/3864; https://nbn-resolving.org/urn:nbn:de:gbv:9-opus-38643; https://epub.ub.uni-greifswald.de/files/3864/Dissertation_Teltewskoi-Annette_2020.pdf

Ice-wedge polygon mires are typical features of the Artic and therefore especially affected by climate change. They show, caused by soil-ice action, an amazing regular polygonal structure in meter dimension of higher and lower elevated dry and wet parts, and to this microtopography adapted vegetation. Polygon mires play, analogous to other mires, an important role in carbon sequestration, water balance, wildlife habitat and archive value with local to global significance. By storing enormous amounts of the global soil carbon polygon mires are crucial for our climate. Despite this relevance by covering large areas, polygon mires are comparatively poorly scientifically investigated and understood. It is still difficult to make forecasts on how polygon mires will develop under a changing climate in the Arctic, especially because internal factors and self-organisation complicate the understanding of their functioning. Therefore the investigation of modern and past polygon mires is necessary. This dissertation presents high resolution palaeo-ecological studies of a Northeast Siberian model polygon: ice-wedge polygon Lhc11 located in the Indigirka Lowlands at the scientific station Kytalyk. During field work in July 2011 the study site, covering an area of 26 × 21 m was divided into 546 plots, in which vegetation composition and microtopographical elevation characteristics were assessed and surface samples were collected. For palaeoecological analysis a 105.5 cm long peat section was excavated from the same site. Cluster analysis revealed five plant communities, which are clearly separated with respect to ground surface height, frost surface height and coverages of open water and vegetation, confirming the pattern already identified in other studies of Arctic ice-wedge polygons. The correct recognition of these patterns is crucial in palaeoecological studies in order to reconstruct landscape elements and their dynamics. This recognition requires insight in the short-distance relationships between surface ...