Earth`s Cryosphere, 2017, Vol. XXI, No. 6, p. 3-11

CHANGES IN VEGETATION AND GEOCRYOLOGICAL CONDITIONS OF THE TAZOVSKY PENINSULA (EASTERN PART) FOR THE PERIOD OF 1988–2016

D.V. Moskovchenko^1,2, S.P. Arefyev^1,2, V.A. Glazunov², A.A. Tigeev²

¹ Tyumen State University, 10, Semakova str., Tyumen, 625003, Russia; moskovchenko1965@gmail.com

² Institute of the Problems of Northern Development, Tyumen Scientific Centre, SB RAS,
86, Malygina str., Tyumen, 625026, Russia; va@ipdn.ru

Based on field geobotanical descriptions, remote sensing data and analysis of tree-ring chronologies, the dynamics of vegetation in the eastern part of the Tazovsky Peninsula has been studied. The dynamics of vegetation has been shown to be caused by climate changes, and the radial growth of larch, as well as drainage of thermokarst lakes, increases under the influence of climate warming. Reduction in the area of lakes proved to be 20 %, corresponding to the maximal parameters in Western Siberia, suggesting activation of thermoerosion processes. Radial growth of larch has increased at the watershed more than in the floodplain of the Mongayurbey River, indicating an increase in the thickness of the active layer and levelling of the temperature field in various landscape conditions. Anthropogenic succession of vegetation was caused by disturbances during development of the Yurkharovskoye gas field. The sedge-cotton grass and grassy-herb communities of drained lakes (“khasyreys”) are restored most rapidly (within 3–4 years) after anthropogenic disturbances. However, the process of formation of dwarf birch-shrub-lichen-moss communities in their place, accompanied by a decrease in the depth of seasonal thawing, takes more than 30 years. The off-road vehicle tracks and other linear disturbances can be traced for 12–20, in rare cases for 25 years on satellite images. Calculation of the normalized difference vegetation index (NDVI) has demonstrated its dependence on air temperatures in the summer and the amount of precipitation of the preceding period, starting from the date of snow cover formation.

Tundras, Tazovsky Peninsula, dynamics of vegetation, climate changes, tree-ring width chronologies, cryogenic processes