Holocene Dynamics of Vegetation and Ecological Conditions in the Center of the East European Plain

Changes in the vegetation and fire regimes in the central East European Plain during the second half of the Holocene have been reconstructed based on the results of paleobotanical analysis and radiocarbon dating of material from a section of peat deposit in the Mordovia State Nature Reserve. It has been shown that birch–pine forests were widespread in the region between 7000 and 5000 yr BP, with the frequency of fires in that period being high (the fire return interval ranged from 10–20 to 100 years). Beginning from 5000 yr BP and to the early 20th century, broadleaf forests were dominant, with the fire return interval increasing to 300–500 years or longer.     

Leaf Area Indices of Forest Stands in Natural and Disturbed Forests of Primorsky Krai

Russian Journal of Ecology - Leaf area indices (LAIs) of stands in natural forests and forests disturbed by felling and fires in Primorsky Krai have been determined using data on the foliage...     

Forest-ecological consequences of fires in light conifer forests of Transbaikalia

Consideration is given to the results of studies on the postfire dynamics of Transbaikal forests, which are formed under conditions of highly arid climate and extreme pyrological regime. Data are presented on tree die-off and recruitment in naturally burned forests and in test stands affected by creeping fires differing in intensity. The hydrothermal regime of soils, precipitation runoff, and its multifactor models are discussed. It is shown that fires aggravate moisture deficiency on mountain slopes, impair the productivity of tree stands, and cause their digression. The statistics of forest fires and the risk of lightning fires are analyzed.     

Models of taiga-steppe communities on the western coast of Lake Baikal

As a result of monitoring spatial changes in the cenotic structure of plant communities at the taiga-extrazonal steppe boundary on the western coast of Lake Baikal, models of taiga-steppe communities reflecting the formation, dynamics, and genesis of forests in the taiga zone have been constructed. Changes in the species composition of communities, mesophytization of steppes, the expansion of moss synusiae characteristic of polydominant dark conifer and light conifer taiga forests, active forest invasion into steppe areas, and the presence of dark conifer tree species in light conifer forests have been revealed.     

Dynamics of plant communities in insular pine forests of Krasnoyarsk forest-steppe

The dynamics of vegetation have been studied in forest-steppe pine (Pinus symvestris L.) forests affected by anthropogenic factors such as felling and fires. Gradient analysis has been used to reveal specific ecological features of plant communities and trace the main directions of succession. The results show that these forests are at different stages of progressive succession, with the development of theircommunities following similar trends over the past few decades.     

Long-term dynamics of summer bird communities in the Arkaim reserve

Nesting bird communities of individual habitat types in the Arkaim reserve are formed every year under the influence of nonrandom factors. Their qualitative and quantitative composition may gradually shift in a certain direction, but more often it remains relatively stable over several years and then makes an abrupt transition into a different state. The strongest effect on the dynamics of these communities has been exerted by progressive succession following the assignment of special protection status to the Arkaim area. The effects of fires and other elemental factors are also significant.     

Common Shrew (Sorex araneus,Eulipotyphla) Population and the Food Supply of Its Habitats in Ecologically Contrasting Environments

Russian Journal of Ecology - Studies in the fir?spruce forests of the Middle Urals, in habitats with varying degrees of transformation by natural disasters (windfalls and fires), have shown...     

“Double carousel” of the succession process in a regional ecosystem

Southern taiga forests of Western Siberia are used as an example to demonstrate the mechanism of “flickering“ in the mosaic pattern of plant cover, which reflects natural, regular cycles of progressive succession starting at different times in each contour of the geobotanical map. The primary plant formation with time depletes the resources of its ecotope, transferring biophilic elements from the soil to the phytomass, fruits, and seeds. Its immunity is gradually impaired, making the formation vulnerable to the attacks of pests, diseases, and fires. Its death is followed by a cycle of progressive succession, which renews the ecotope resources and allows the primary formation to move within its range, despite that the trees are fixed and immobile, which provides for its indefinitely long existence.     

Refugia for the floristic diversity of Northern Ural dark conifer forests as markers of natural vegetation of the eastern European Taiga

New data are presented on unique refugia accounting for the high floristic diversity of dark conifer forests of the Northern Urals, which have some of the highest parameters of species saturation among boreal forests of northern Eurasia. Based on the results of analysis, the most significant biological factors have been revealed and their influence on boreal tall-herb and background plant communities has been evaluated.     

Typological and species diversity of dark conifer forests in the lower reaches of the Bol’shaya Porozhnyaya River, a tributary of the Pechora (Pechora-Ilych state nature reserve)

The structure of dark conifer forests in the lower reaches of the Bol’shaya Porozhnyaya River is described. Ordination of corresponding communities has been performed, and their ecological and ecocenotic characteristics and species structure have been analyzed. On this basis, a typological scheme of the forests has been constructed following the method by L.B. Zaugol’nova. The identified sections and variants of communities within the true moss and tall herb sections are described. Successive change of leading ecological factors in the hierarchical series of communities, from sections to variants, is demonstrated.     

Response of the Avifauna to Technogenic Environmental Pollution in the Southern Taiga Zone of the Middle Urals

The results of original studies and published data are used for evaluating the main responses of the avifauna of boreal forests to the combined effect of sulfur dioxide and heavy metals. It is shown that environmental pollution results in the reduction of species richness, biomass, and stability of the nesting bird fauna. In degraded areas, the structure of the bird community changes: (1) typical forest species are replaced by the species of open habitats, and (2) the proportion of species nesting in the upper tree layer decreases, whereas that of ground-nesting species increases.     

Vegetation restoration dynamics in the forest-steppe system of the middle Volga region

The current dynamics of ecosystems of the forest-steppe system is most adequately described via determining the probable trajectories of changes in its elements in a simple Markov chain. The obtained data have made it possible to determine the direction of succession and draw its scheme. Theoretically possible series of community development are presented. The succession of community restoration from the spread of shrubs over steppificated fallow lands to the formation of low forests of European bird cherry has been analyzed. The restoration cycle of ecosystem dynamics is described by eight age stages.     

The Spatiotemporal Pattern of Fires in Northern Taiga Larch Forests of Central Siberia

The periodicity of fires in larch forests of Evenkia and their relationship with landscape elements have been studied. Cross-sections with “burns” in them caused by past fires have been analyzed in 72 test plots; the fire chronology encompassed the period from the 15th to the 20th century. The between-fire intervals (BFIs) have been calculated by two methods: (I) on the basis of burns alone and (II) on the basis of burns and the start of growth of the new generation of larch after the earliest fire. The BFI depends on local orographic features; it is 86 ± 11 (105 ± 12), 61 ± 8 (73 ± 8), 139 ± 17 (138 ± 18), and 68 ± 14 (70 ± 13) years for northeastern slopes, southwestern slopes, bogs, and flatlands, respectively. The mean BFIs calculated by methods I and II are 82 ± 7 and 95 ± 7 years, respectively. The permafrost horizon rises at a mean rate of 0.3 cm per year after a forest fire. It has been shown that the number of fires regularly peaks at periods of 36 and 82 years. There is also a temporal trend in fire frequency: the mean BFI was approximately 100 years in the 19th century and 65 years in the 20th century.     

Non-market economic valuation of the benefits provided by temperate ecosystems at the extreme south of the Americas

The island of Navarino, Chile, located at the extreme southern end of the Americas, is one of the few regions in the world with undivided and only slightly transformed temperate forests. Currently, fundamental issues are being addressed, such as how local fuel wood demands will be met without destroying primary forests and how a sustainable tourism industry may be developed. This study aims to inform these planning processes by providing data on the economic valuation of several non-market benefits provided by the temperate ecosystems of Navarino Island that have relevance to the local population. We focus this valuation on landscape esthetics, nature access restrictions, esthetic and ethno-symbolic benefits at the species level and the existence value of non-vascular endemic species. A choice experiment was applied to a sample of local residents (n = 230). Decisions about future development strategies were influenced by landscape esthetics being threatened by progressing levels of tourist infrastructure, nature access restrictions in favor of both economic and conservationist concerns, continued visits of an ethno-culturally important hummingbird, the protection of a moss endemic to the sub-Antarctic forests and species diversity. From a non-market valuation perspective, local residents favor a low-impact tourism development scenario. Little is known about the monetary value of Chile’s temperate forests. Knowledge of the economic value of Navarino’s temperate forests facilitates the understanding of local natural resource management at the microlevel and assists in formulating conservation policies at the regional and national levels.     

Vegetation-permafrost relationships in the zone of sporadic permafrost distribution in the Kamchatka Peninsula

Studies on vegetation and permafrost table depth in the zone of sporadic permafrost distribution in the Uksichan River valley (the central Kamchatka Peninsula) have provided evidence that these components of biogeocenosis are interrelated and develop coordinately. In open larch forests with green forest mosses dominating in the ground vegetation layer, the permafrost table lies approximately 60 cm below the soil surface. When the ground vegetation layer is dominated by sphagnums, the permafrost table rises to 40–20 cm. In areas with a dwarf shrub-lichen ground layer, the soil thaw depth increases. A hypothesis is proposed that cyclic successional replacement of plant communities may take place in open larch forests on permafrost soils, including four consecutive stages with dominance of green mosses, sphagnums, lichens, and dwarf shrubs. In areas disturbed by fires, pioneer moss or herbaceous communities develop in the ground layer.     

Influence of Clear Fellings on the Bryophyte Component of the Broad-leaved Forests of the Bashkir Cis-Ural Region

The change in the composition of the bryophyte component of succession communities that occur in the process of natural regeneration at the site of clear felling of the indigenous elm—maple–linden forests of the Bashkir Cis-Ural Region has been studied. The vulnerability of species to the consequences of felling is affected by their substrate confinement, ecological amplitude in relation to the factors of temperature, humidity, variability of soil moisture, and type of life strategy. In the secondary aspen forests, the absence or low constancy of nemoral epiphytic and ground mosses was noted.     

金沙江干热河谷几种引进树种人工植被的生态学研究

采用标准木法和收获法,对金沙江元谋干热河谷几种引进树种的人工植被（即赤桉×新银合欢混交林、赤桉纯林、新银合欢纯林和印楝纯林）各层植被生物量与天然次生植被（坡柳-扭黄茅灌草丛）进行了比较研究,同时对各类植被的物种组成和物种多样性进行了比较分析。结果表明：（1）采用引进树种人工恢复的植被积累了大量生物质,总生物量大小依次为：赤桉×新银合欢混交林（4491 t/hm2）>新银合欢纯林（3991 t/hm2）>赤桉纯林（3857 t/ hm2）>印楝纯林（1306 t/hm2）>天然次生林（935 t/ hm2）。人工恢复植被生物量主要集中在乔木层,天然次生植被生物量主要集中在灌木、草本和凋落物层。（2）人工恢复植被的物种数均少于天然次生植被,而且不同植被的物种数和物种组成也存在差异。（3）各植被的Shannon wiener多样性指数和Margalef丰富度指数均表现为：印楝纯林>坡柳-扭黄茅灌草丛>赤桉纯林>赤桉×新银合欢混交林。在Alatato均匀度指数方面,各人工植被之间的差异不大,但人工植被与天然次生植被之间有显著差异。〖     

Spatial differentiation of the total bird population in a definite area

The spatial structure of the total bird population at the level of communities has been studied in a definite area at the boundary between northern open forests and forest-tundra. The boundaries of communities have been delimited by mapping out areas with a homogeneous species composition. The pattern of communities is shown to be as follows: the species-richest part of a local species assemblage (characteristic of a given landscape type) forms the basic community, which is surrounded by poorer communities of increasingly variable composition and configuration, depending on distance from the basic community. The most distant communities consist almost exclusively of abundant and widespread species. A group of borderline communities of mixed composition is located at the boundary between two landscape complexes. Mechanisms accounting for such a pattern are discussed.     

Analysis of trends in the formation of species richness of plant communities using syntaxonomy and ecological scales

On the basis of syntaxonomy of primary forests in the Southern Ural region, an analysis of trends in the formation of their species diversity has been performed in regard to heat supply, soil moisture, and general soil richness. The roles of environmental factors have been estimated using Landolt’s scales. The results have shown that communities of forest classes Querco-Fagetea, Brachypodio-Betuletea, and Vaccinio-Piceetea differ in the trends of changes in species richness along gradients of the above factors. In communities of all these classes, species richness depends primarily on heat supply, with soil richness being the second most important factor.     

Density of Scots pine undergrowth after ground fires in a zone of industrial air pollution

The effects of two exogenous factors, ground fires and industrial air pollution, on natural regeneration of Scots pine (Pinus sylvestris L.) cenopopulations have been studied in the Transural region. It has been found that an increased level of air pollution leads to a decrease in the abundance and occurrence frequency of pine undergrowth; as the intensity of ground fire increases, these parameters of the postfire generation of undergrowth increase as well, especially in background areas. As shown by two-way ANOVA, either of these factors and their interaction have a significant effect on the density of pine undergrowth, with this effect being stronger in the case of ground fires.