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Biogeographical patterns of the grasslands’ syntaxa distribution in the Northern Eurasiaтезисы доклада
- Авторы: Belonovskaya Еlena, Tishkov Arkadiy
- Сборник: Asian grassland conference. Book of Abstracts. Virtual Conference. 19-21 April 2022
- Тезисы
- Год издания: 2022
- Первая страница: 19
- Последняя страница: 19
- Номер статьи: OP08
- Аннотация: Question (Aims). As it was mentioned in the review on Russian temperate meadows and steppes (Tishkov et al., 2020), for Northern Eurasia, and, consequently, for Russia, grasslands are an inherent element of a treeless landscapes. They form great diversity of natural and secondary (anthropogenic) communities, occupying large spaces on plains within tundra and forest zones, forming steppes biome and widely spreading above timberline in high-mountains. According to the recent phytosociological overview (Ermakov, 2012), the diversity of Russian grasslands comprises 23 classes, 50 orders, and 117 alliances. Our aim is to identify the important borders of their distribution and reveal peculiarities and factors responsible for it. Location. Territory of Russian Federation. Materials and Methods. Analysis of the main grasslands classes’ geographical distribution according different biogeographic regions. Results. The boundaries between the biogeographic units identified in Russia (for example, Mediterranean, Caucasian, Siberian, Central Asia, Far Eastern, Beringian, and others) are traceable regarding the distribution and composition of temperate grassland communities. For example, wide spread European communities of natural and semi-natural meadows of Molinio-Arrhenatheretea are replaced in the Central Siberia and Far East by vicarious communities of eastern class Calamagrostietea langsdorfii. The same situation with steppes. In the East communities of dry grasslands of the class Cleistogenetea squarrosae take place of the European steppes of Festuco-Brometea. It appeared to be that while the Urals Mts is of no significance in this respect, the wide valley of the Yenisei River is an important boundary both for above mentioned communities and for many of the inhabitants of the grasslands. The steppe fauna demonstrates effects of some species vicariance from west to east. A good example is the sequence of the Sciuridae rodents’ species replacing one another from western to the east. Conclusions. Apparently, the main reason of this phenomenon is ancient disjunction of two Pre-Cambrian platforms: of the Russian and Siberian ones estimated by several hundreds of millions years. As for vegetation of meadows in tundra and high-mountains, communities of the main classes are met all along of the continent. Absence of diversity and lack of clear biogeographical boundaries can be explained by the relative youth of the northern and mountains territories (caused by recent glaciations and aridization cycles) estimated only by several hundreds and decades of thousands years. However, this is not yet sufficient for the processes of phylocenogenesis, which form high-level syntaxa and establish biogeographic boundaries. References: Ermakov, N.B. (2012) Prodromus of the higher vegetation units in Russia. The actual status of the basic concepts of the vegetation science (Mirkin, B.M. & Naumova, L.G.). Ufa, 377-483. Tishkov, A., Belonovskaya, E., Smelansky, I., Titova, S., Trofimov, I. & Trofimova, L. (2020) Temperate Grasslands and Schrublands of Russia. Encyclopedia of the World's Biomes. Vol. 3. Grasslands and Schrublands - Sea of Plants. US: Elsevir, 725-749.
- Добавил в систему: Белоновская Елена Анатольевна