Macroelements composition of raised bogs peat in the middle taiga of Western Siberia(the bogs complex Mukhrino)

Underthe condition of technogenic pressure on waterlogged landscapes, the problem of climate change leading to glacier melting, permafrostdegradation, flood, because of disturbance in heat and mass exchange between land and ocean, is very topical. Atmospheric fluxes withaerosol parts move towards zones with lower temperature and higher moisture and precipitate there. Such chemical elements as N, Р, К,Са, Mg, S containing in dust are used by plants to create organic substances. The aim of the work is to reveal the character of macroelementscontribution in peat deposits formed in different oligotrophic mire ecosystems geochemically connected to each other. Theinvestigation of macroelements contribution in peat deposits was carried out in 5 ecosystems of a bog complex situated in the lowerterrace of the Irtysh in Kondinsk geochemical region. The thickness of peat deposits varies from 1.3 to 3.5 m. According to morphologicalfeatures, ash content and pH, in peat deposits of tree ecosystems - low ryam, hollow and poor fen - four peat layers are distinguished.The upper peat layer consists of sphagnum remains, with ash content 1.1-6.3 (3.7)%, рН 3.2. The second layer is mesotrophic,the ash content increases up to 10.9%, and the higher value of pH (2.9) is observed. The third part with oligotrophic peat has the ashcontent of 1.7% and рН 3.7-3.9. The lower peat part is also mesotrophic peat. The ash content reached 14.5 and average 7.5%, pHranges from 3 to 3.7. The peat deposit of the tall ryam ecosystem is divided into three parts: oligotrophic peat of 10 cm layer, 40 cm ofmesotrophic peat and the lower peat layer (80 cm) consists of eutrophic peat. The ash content increases from 2.6% in the upper layer to14.8% in the lower layer (average). The macroelements contribution is the same in peat soil profiles of all ecosystems - the content ofmacroelements increases in the upper and lower parts of profiles. In the upper part they accumulate biogenically, in the lower part of theprofile they accumulate under the influence of underlying mineral horizons. Migration processes level genetic differences in contributionof macroelements content in peat soil profiles. A difference of potassium content in the living phytomass and the peat layer of 0-30 cm in bog ecosystems was found. The biological absorption coefficient of potassium varies from 1.5 (ridge) to 11 (oligotrophic hollow),which indicates its rapid leaching from dead parts of mosses, grasses and dwarf shrubs by bog water during their decompositionand absorption by living roots. Nitrogen content increases with the increasing of trophic elements in peat layers. In the tall ryam it variesfrom 0.9 to 1.4% in peat deposits. In the low ryam ecosystem it ranges at 0.4-1.5%. In the ridge-hollow complex, the hollow is richerwith nitrogen - 0.8-2.1. In swamps the nitrogen content is similar to the hollow.

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