Dry Cover Peatlands on the Islands of Kandalaksha Bay, the White Sea
Dry cover peatlands have been investigated on 11 islands of the Kandalaksha Bay in the White Sea. The peatlands occupy the central convex parts of islands or some of their capes and gentle slopes up to 5° following the mineral surface of the island. Their modern vegetation is represented by xeromorp...
Main Authors: | , , , , , |
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Other Authors: | , |
Format: | Article in Journal/Newspaper |
Language: | Russian |
Published: |
Izvestiya Rossiiskoi Akademii Nauk. Seriya Geograficheskaya
2023
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Subjects: | |
Online Access: | https://izvestia.igras.ru/jour/article/view/1669 https://doi.org/10.31857/S2587556622060073 |
Summary: | Dry cover peatlands have been investigated on 11 islands of the Kandalaksha Bay in the White Sea. The peatlands occupy the central convex parts of islands or some of their capes and gentle slopes up to 5° following the mineral surface of the island. Their modern vegetation is represented by xeromorphic Empetrum heaths. Peatlands develop directly on rocky surfaces, as well as on sand and pebbles that overlap them. The peat formation on the island surfaces begins as they go beyond the supralitoral zone due to the land uplift continued at the present time. The peat deposit thickness, on average, is about 30 cm, reaching a maximum of 71 cm. Botanical macrofossil analysis of peat showed that peat accumulation begins both at the stage of coastal meadows and at the stage of Empetrum heaths. The main peat forming plants are crowberries, blueberries, cloudberries, green mosses and some other species present in modern xeromorphic communities. Accordingly radiocarbon dating of the bottom layers of peat, the vertical uplift rate of the islands’ surface is relatively uniform and is estimated at 4 (to 5) mm per year, which corresponds to the uplift rate of the mainland coasts of the bay. The measured radiocarbon age of peatlands ranges from 425 to 1840 years, the estimated age is up to 2760 years. The peat accumulation rate is relatively constant throughout the existence of peatlands and is estimated, on average, at 0.14–0.15 mm per year. The study disproof the previously made assumption about the relict nature of Empetrum heath peatlands. Исследованы сухие покровные торфяники на 11 островах Кандалакшского залива Белого моря. Торфяники занимают выпуклые центральные части островов или их отдельных мысов и пологие склоны крутизной до 5°, следуя за минеральной поверхностью острова. Их современная растительность представлена ксероморфными вороничниками. Торфяники развиваются непосредственно на скальных поверхностях, а также на перекрывающих их песке и гальке. Заторфовывание поверхностей островов происходит по мере их выхода за ... |
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