Myxomycetes of the Urals

МИКОЛОГИЯ И ФИТОПАТОЛОГИЯ Том 44 2010 Вып.4 УДК 582.241(234.850) © K. A. Fefelov MYXOMYCETES OF THE URALS ФЕФЕЛОВ К.А. МИКСОМИЦЕТЫ УРАЛА Myxomycetes (plasmodial slime molds, class Myxogasteromycetes) are common inha- bitants in terrestrial ecosystems. They prefer to develop on different decaying plant materi- als. The first records of myxomycetes species from the Ural Mountains reported by A. A. Yachevskii (1907), where common species, like Lycogala epidendrum, were reported from Perm region. Lateron, A. V. Sirko collected myxomycetes in the 1960—1970 s. Ho- wever, her collections were identified only partly and are not published. The first special studies on myxomycetes have been begun at the end of 20th century. In the Subarctic and Arctic areas of Russia 31 species from the Polar Ural (Novozhilov et al., 1998; Karatygin et al., 1999) are known. The data on myxomycetes of south parts of the Urals include records from Sverdlovsk region (Novozhilov, Fefelov, 2001; Mukhin et al., 2003; Fefelov, 2006; Plotnikov, Fefelov, 2008) and the South Ural (Fefelov, 2003). Besides, there are known in- vestigations on myxomycetes of adjoining territories of the West Siberia: West-Siberian plain (Fefelov, 2002) and the Altay Mountains (Novozhilov, 1986; Barsukova, 2000; Novo- zhilov et al., in press). Our data are based on published records and collections obtained by author in numerous expeditions in the Urals. The field works were carried out during the field seasons of 1996—2007 in all vegetation types and typical habitats of studied region using transect method. Different substrates (decaying logs, litter, fungi, mosses, bark of living trees, dung of herbivorous mammals and birds) were studied to find mature myxomycete sporophores (fruit bodies). Additionally, bark from living trees, litter, dung of herbivorous animals, mosses were collected for moist chamber cultures. Altogether 1854 moist chamber cultures (Hдrkцnen, 1977; Novozhilov et al., 2000) were made in the Institute of Plants and Animals Ecology UrD RAS. A record is defined herein as one or more fruiting bodies of a species that developed from a moist chamber culture or found from one microhabitat (e. g. trunk, log etc.). Nomenclature used herein follows Lado (2001) for myxomycetes, and Gorchakov- skii (1975) for vascular plants and plant communities. Collections of the myxomycetes in- clud about 4000 specimens and deposited in the Institute of Plant and Animal Ecology RAS (SVER) and partly in the Komarov Botanical Institute RAS (LE), Russia. To compare the species communities in different geographical areas, an index of com- munity similarity (CC = Chekanovskii coefficient) was used as proposed by Zaitzev (1984). The formula CC = 2c/(a + b) used to calculate this index is based on the presence or absence of species; a, b — number of species in comparable lists of geographical areas; c — number of common species. Therefore, the value of CC ranges from 0 (the data sets share no common species) to 1 (all species are present in both data sets). As an indicator for species diversity, we used the mean number of species per genus (S/G). Occurrence of a particular species was estimated with a simple percentage scale. 340 We estimated the index of specificity for each territory (SI) to compare the species lists. This index was used only for comparison of two or several territories. The value of SI ranges from 0 (all species of the one territory are found on another) to 1 (no common species for this and other territories). The Urals (Ural Ridge, Ural Mountains) is north-south oriented ridge over 2000 km long, which extended across Russia from tundra of Arctic till steppe of Kazakhstan. The he- ight of some mountains is 1895 m in the north part and 1639 m in the south part of the ridge. The climate is heterogeneous and moderately continental, but with quite specific characters. The Ural Mts are a natural barrier on the way of air masses moving from west to east and therefore they deter the influence of the Atlantic Ocean. Climatic differentiation between the west and east slopes of the ridge is result of deformation of air current. Annual precipitation in the highest places on the north is over 800 mm and about 600 mm on the south. To the west and east this parameter is decrease till 300—400 mm. The driest regions are situa- ted in the eastern parts of study area. The west slopes adjoined with plains have maximum precipitation especially in summer period. Other climatic effect known as «rain shadow» is occurred over the Urals to the east lowlands. Precipitation on this territory has minimum value in all study area, even including hills of the western Urals (Kaigorodov, 1955; Chiki- shev, 1966; Kuvshinova, 1968). Vegetation of the region is rather various. Taiga occupies major portion of the territory and is represented by different plant communities. Dominate tree species include: fir, larch, pine, and spruce. In the South Ural, taiga turns into broad-leaved forests with elm, linden, maple, and oak. Steppe communities occur in the southern areas of the Urals. Tundra and forest-tundra cover large territories in the north (Gorchakovskii, 1975). In geography, the Ural Mts are divided into 5 geographical areas: Polar, Subpolar, North, Middle and the South Ural (Borisevich, 1968). Main study plots and geographical areas are shown on the figure below. Arctic territories of the Ural Mountains (AU) include the Polar (PU) and the Subpo- lar (SPU) Urals. This area begins on Barents Sea coast and stretches till 64°00S N, with maximum elevation in the Subpolar Ural (Narodnaya Mt., 1895 m). Annual average air temperature (AT) is –5—8 °С, AT of July (ATJ) is 5—15 °С, period without frost (PWF) — 67—91 days, annual precipitation (AP) — 400—600 mm, average temperature of soil (ATS) is –1.5 °С. Vegetation is represented by different types of tundra and forest-tundra communities with lichens, mosses, grasses and shrubs. Dominants are Duschekia fruticosa, Betula nana, B. tortuosa, Larix sibirica, L. sukaczewii, Picea obovata and numerous species of Salix. South- ward vegetation is formed by open coniferous forests (canopy coverage is less than 60 %) with spruce (Picea obovata) and birch (Betula pubescens) in the western regions. In the eastern regions dominant trees are larch (Larix sibirica) and pines (Pinus sibirica and P. sil- vestris). North Ural (NU: 64°00S—59°15S N) is characterized by high range of altitude. The highest point is Telpos-Iz Mt (1617 м). Main parameters of the climate are: AT is –1.5 °С, ATJ is 10—20 °С, PWF — 67—91 days, AP — 560—605 mm, ATS is –1.5 °С. The North Ural includes north and middle taiga vegetation subzones. Main tree species in forests of the north taiga is spruce, but along the river banks on the sand soil it is pine. Eastwards there are pine and spruce sometimes spruce-cedar pine forests. Aspen (Populus tremula) form rare riparian forests in the river valleys. In understory lichens and mosses prevail on soil. Westwards, spruce and pine forests prevail whereas eastwards — pine and fir-spruce-cedar pine forests. Secondary birch forests widely distributed in this area together with coniferous forests. In the middle taiga aspen grows out of river valley. Shrubs and tall herbs are well developed. In the highland, mountain tundra, as well as birch and larch open mountain forests dominate. Middle Ural (MU: 59°15S—55°54S N) is low part of the Ural Mts. Elevationis up to 1000 m. Climate: AT is — 0.8 °С, ATJ is — 15—20 °С, PWF — 84—115 days, AP — 460—620 mm, ATS is — 1.5 °С. Heve there are two vegetation zones: middle and south taiga. In the west, fir-spruce forests prevail over pine forests. In the east, there is an opposite situation. Species of birch (B. pu- 341 Studied areas and geographical division of the Ural Mountains. 1 — main study plots, 2 — border of geographical areas, 3 — border of the Ural Mountains. PU — Polar Ural, SPU — Subpolar Ural, NU — North Ural, MU — Middle Ural, SU — South Ural. bescens and, rarely, B. pendula) are presented in the coniferous forests as subdominants. Therefore, some areas are occupied by secondary forests. In the west, broad-leaved trees: linden (Tilia cordata), maple (Acer platanoides), elms (Ulmus laevis, U. scabra) are found in the spruce forests. Understory is good developed and has high species diversity. Vascular plants have particular importance in the overground coverage. Mosses coverage is sicker. South Ural (SU: 55°54S—51°00S N) is divided on two parts: north — mountainous and south — plateau. In this area mountain system is very wide (about 120 km) and represented by chains of mountains including the highest: Yremel Mt (1568 m) and Yamantau Mt (1639 m). Climate: AT is — 1.6 °С, ATJ is — 15—25 °С, PWF — 104—142 days, AP — 400— 570 mm, ATS is — 2.5 °С. 342 In this part of the Ural Mts vegetation is most various. There are four vegetation zones: taiga, broad-leaved forests, forest-steppe and steppe. Broad-leaved forest zone is characterized by mixed broad-leaved-coniferous forests and European broad-leaved forests with oak (Quercus robur), hazel (Corylus avellana) and spindle (Euonymus verrucosa) and others ha- bitants of the south taiga. Forest-steppe includes a scattered forest islands with aspen, birch and pine within the north steppe and meadow vegetation. Aspen, birch, cottonwood (Popu- lus nigra and P. alba), pine and willow (Salix alba) are found in the steppe only in wet places near water. Analogs of tundra and forest-tundra, opened birch and fir-spruce park forests are distributed in highlands of the South Ural.

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