Western Siberian Peat Bog

Western Siberia includes the largest peat bog in the world. Its core area lies between the Ural Mountains and the Yenisey River extending over 1800 km from west to east and 800 km from north to south and containing 40% of all peat deposits on the planet. The excess water causes a lack of oxygen and gives rise to the formation of methane. The gas is created in massive quantities and when it escapes to the surface often kills surrounding vegetation. If the surface peat is drilled the escaping gas is often under such pressure that it can cause fountains of liquid peat. These upwellings appear to be partially responsible for the numerous lakes of black bog water, estimated to exceed 100,000, and these together with the vast area of bog constitutes one huge hydrological system. The peat thickness ranges from 4-7 m and most of it is very low in nutrients (oligotrophic). Of the vegetation, about 60% consists of mixed Sphagnum bog often dominated by Sphagnum fuscum, while 10% is a complex largely dominated by Eriophorum vaginatum, Scheuchzeria palustris and Sphagnum species such as S. angustifolium, S. balticum, S. dusenii, S. fuscum and S. magellanicum. Throughout the bog other vascular plants include Andromeda polifolia, Betula nana, Chamaedaphne calyculata, Drosera longifolia, Leda palustre, Menyanthes trifoliata, Oxycoccus microcarpus, Rubus chamaemorus and Vaccinium uliginosum. In places the local drainage is sufficient to allow small patches of forest to develop which are usually dominated by Pinus sibirica, P. sylvestris or Betula pubescens.

Western Siberian Palsa Mires

These mires comprise frozen mounds or ridges (palsas) up to 8 m high, which alternate with wet hollows. In Western Siberia they are largely confined to the lowland areas between the Ob and Yenisey rivers where the dominant vegetation is either northern taiga or southern forest tundra. The vegetation mainly consists of dwarf shrubs such as Betula michauxii, Ledum decumbens, Vaccinium uliginosum and V. vitis-idaea. The wet hollows are dominated by sedges such as Carex limosa, C. rostrata and C. rotundata, and cotton grasses mainly Eriophorum angustifolium and E. russeolum. Herbs are few in number but may include species such as Menyanthes trifoliate, while some palsas also have a scattering of trees like Betula pubescens, Larix sibirica and Pinus sibirica.

Western Siberian Fen

These are mainly situated in the forest steppe and steppe zones of the Western Siberian lowlands, but they have a complex pattern of variation. They include various eutrophic fens with mosses, sedges and grasses such as Calamagrostis neglecta and Scolochloa festucacea.

References

Botch, M. S. & Masing, V. V. (eds). 1983. Mire Ecosystems in the USSR. In: Ecosystems of the World 4B. Mires: swamps, bogs, fen and moor. Ed. A. J. P. Gore.  Elsevier Scientific Publishing Company.

Knystautas, A. 1987. The Natural History of the USSR. Century Hutchinson Ltd.

Lapshina, E. D. & Yugra, S. 2006. The vegetation of Ob valley mires in the southern forest zone of West Siberia. Phytocoenology, 36: 421-463.

Malyshev, L. I., Balkov, K. S. & Doronkin, V. M. 1999. Spatial diversity of the Siberian flora. Flora, 194: 357-368.

Walter, H. 1977. The oligotrophic peatlands of Western Siberia – the largest peino-helobiome in the world. Vegetatio, 34: 167-178.