Modern and Fossil Diatom Assemblages from Bol'shoy Lyakhovsky Island (New Siberian Archipelago, Arctic Siberia)
O. V. PALAGUSHKINA1, S. WETTERICH2, L. SCHIRRMEISTER2, L. B. NAZAROVA1,2,3
1Kazan Federal University, 420008, Kazan, Kremlevskaya str., 18
2Alfred Wegener Institute Helmholtz Center for Polar and Marine Research, 14473, Potsdam, Telegrafenberg A43
3University of Potsdam, 14476, Potsdam-Golm, Karl-Liebknecht str., 24-25
Keywords: высокоширотная Арктика, о-в Бол. Ляховский, диатомовые, экологические факторы, плейстоцен, голоцен, high Arctic, Bol’shoy Lyakhovsky Island, diatoms, ecological factors, Pleistocene, Holocene
Abstract
We present results of taxonomic and ecological investigation of diatoms from polygonal ponds and Quaternary permafrost deposits of the Bol’shoy Lyakhovsky Island and a reconstruction of climatic changes on the island during Late Pleistocene/Holocene transition using fossil diatom assemblages from the permafrost deposits. The taxonomic list of diatoms includes 159 species. Main ecological factors, driving the distribution of diatoms in the investigated area are mean July air temperature, рН, conductivity, water depth, and concentrations of Si4+ and Al3+. Rise of the water depth and formation of stable lacustrine conditions in the ancient thermokarst lake was related to climate amelioration and took place in the Late Pleistocene before 11860 ± 160 yrs BP and during the early Holocene between 11210 ± 160 and 7095 ± 60 yrs BP.
|
