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The climatostratigraphic scale of the Upper Middle Pleistocene in the northwest of the East European Plain contains a number of controversial issues, one of which is the position of the Likhvin (Holstein) Interglacial and lesser warm (interstadial) climatic events. To approach this problem, we have studied two sections of Quaternary deposits, Bolshaya Kosha (a well-known and long-studied natural exposure) and Nazarovo (a new, previously unknown section studied in a borehole), in which warm intervals of the Middle Pleistocene are recognized. In both sections, we performed lithological and paleobiological (carpological, spore-pollen) analyses and luminescence dating. In the Bolshaya Kosha section, seeds of the extinct species Caulinia goretskyi were revealed, which allowed us to attribute the obtained IRSL (ca 250–260 ka) dates to the post-Likhvin Bolshaya Kosha interstadial. The sum of data let us propose that both our IRSL and recently published 230Th/U dates (ca 240–290 ka) underestimate the age by 10–15%, and the post-Likhvin Kosha interstadial deposits were formed in the late MIS 9. In the Nazarovo section, palynological study showed the conditions of a relatively warm interstadial, with a change in the composition of vegetation from northern to middle taiga forests. According to IRSL dating, the section was formed in the MIS 10 late glacial between 330–370 ka. The two studied interstadials bracket the Likhvin (Holstein) Interglacial and sedimentary units in the Bolshaya Kosha section are proposed to have formed in MIS 9e. [ABSTRACT FROM AUTHOR]

Some recent land surface models can explicitly represent land surface process and focus more on sub‐grid terrestrial features. Many studies have involved the analysis of how hillslope water dynamics determine vegetation patterns and shape ecologically and hydrologically important landscapes, such as desert riparian and waterlogged areas. However, the global locations and abundance of hillslope‐dominated landscapes remain unclear. To address this knowledge gap, we propose a globally applicable method that employs high‐resolution elevation, hydrography, and land cover data to concisely resolve explicit land cover heterogeneity for the mapping of hillslope‐dominated landscapes. First, we aggregate pixels into unit catchments to represent topography‐based hydrological units, and then vertically discretize them into height bands to approximate the hillslope profile. The dominant land cover type in each height band is determined, and the uphill land cover transition is analyzed to identify hillslope‐dominated landscapes. The results indicate that hillslope‐dominated landscapes are distributed extensively worldwide in diverse climate zones. Notably, some landscapes, including gallery forests in northeastern Russia and desert riparian in the Horn of Africa, are newly revealed. Furthermore, the proposed strategy enables more accurate representation of explicit land cover heterogeneity than does the simple downscaling of a rectangular grid from larger to smaller units, revealing its capability to concisely resolve land cover heterogeneity in land surface modeling with relatively high accuracy. Overall, we present the extensive global distribution of landscapes shaped by hillslope water dynamics, underscoring the importance of the explicit resolution of heterogeneity in land surface modeling. Plain Language Summary: Local land cover distributions are influenced profoundly by various factors that are not represented fully in current land surface models. In alpine regions, changes in vegetation layers from mountain bases to tops are apparent; this phenomenon is driven largely by climatic factors, such as temperature. Interestingly, similar vegetation changes occur in relatively flat regions due to uneven water distribution on hillslopes. Hillslope water dynamics contribute to the development of unique landscapes, such as gallery forests, and substantially influence local ecological and hydrological conditions. Despite this importance, the global locations and abundance of such landscapes remain mysterious. In this study, we propose a method for the mapping of the global distribution of hillslope‐dominated landscapes using high‐resolution land‐cover, terrain, and climate data. The results reveal that the global distribution of these landscapes, including some newly revealed landscapes such as gallery forests in northeastern Russia, is extensive. In conclusion, our study sheds light on the significant role of hillslope water dynamics in determining vegetation patterns in many parts of the world, highlighting the importance of resolving local features in land surface modeling. Key Points: A catchment‐based strategy is proposed to represent explicit land cover heterogeneity using discretized height bands along a hillslopeLandscapes shaped by hillslope water dynamics are detected in many regions of the world in diverse climate zonesThe proposed strategy can concisely resolve land cover heterogeneity in land surface modeling with relatively high accuracy [ABSTRACT FROM AUTHOR]

Understanding the rate and direction of pyrogenic succession in arid ecosystems, which depends on many factors, including the intensity of grazing and the frequency of pyrogenic expo-sure, will allow for more accurate predictions of the consequences of fire onplant communities, and will assist with better fire management. We studied the vegetation on 55 sites in and near the "Chernye Zemli" Natural Biosphere Reserve that burned at different times or were not affected by fires over the past 35 years and characterized the changes in vegetation cover associated with the impact of wildfire and grazing. The descriptions were grouped into chronological stages according to the time elapsed since the last fire, or into groups according to the frequency of fires. In pairwise comparison of the projective cover of plant species between chronological stages, it correlated most strongly between successive initial stages (for stages 1 and 2, p = 0.003, r = 0.73; for stages 2 and 3, p < 0.001, r = 0.78). Species with an initially higher projective cover were more likely to grow on plots in the first year after the fire: p < 0.03. Plots with rare and frequent fires had similar projective cover of individual species (r = 0.64, p < 0.001). We conclude that in the course of pyrogenic succession, communities are gradually replaced over at least ten years. At the same time, the composition of a plant community at the initial point of succession depends on the prevalence of species in the community before the fire. No fundamental effect of the frequency of fires on the composition of plant communities has been revealed. [ABSTRACT FROM AUTHOR]

The article provides information about the Mshary mire, located in the Smolensk Region of western Russia. The mire is surrounded by a mixed coniferous-broadleaved forest and contains various tree species, shrubs, and undergrowth. The sediment collected from the mire was described and dated using carbon-14 dating. The pollen spectra from the mire indicate evidence of land-use from the Bronze Age/Early Iron Age boundary onwards. The article includes a pollen percentage diagram and identifies six local pollen assemblage zones. The authors express gratitude to individuals who made the expedition possible. [Extracted from the article]

One of the most important problems of environmental sciences is to determine limits for the sustainable functioning of affected ecosystems. The effects of volatile hydrocarbons (such as gasoline and kerosene) on plants in natural ecosystems have been poorly studied to date. The present work outlines the data of a field experiment on the effects of kerosene on the plants of forest and bog communities in Central Russia. In this paper, we model the influence of kerosene spillage on plants growing in a coniferous broad-leaved (aspen–spruce) forest and a raised bog with a subshrub–sphagnum pine forest. We used TS-1 kerosene, which is the most commonly used fuel for commercial aviation in Russia. The applied pollutant (loads of 1 to 100 g/kg) had a significant impact on herbaceous plants, leading to the death of individuals even at minimal doses. The shrubs of the bog community as well as the mosses of both communities were more resistant to kerosene. The recovery processes of plant communities were clearly pronounced as early as 2 years after the application of the pollutant. The level of kerosene threshold exposure, which significantly affects the dominant plants of the herb–shrub layer, can be defined as 1–5 g/kg for the forest community and 5–10 g/kg for the bog community. [ABSTRACT FROM AUTHOR]

In recent years, the vegetation cover in urban agglomerations has been changing very rapidly due to technogenic influence. Satellite images play a huge role in studying the dynamics of forest vegetation. Special programs are used to process satellite images. The purpose of the study is to analyze forest vegetation within the territory of the Tomsk agglomeration based on Landsat remote sensing data for the period from 1990 to 2022. The novelty of the study is explained by the development of a unique program code for the analysis of Landsat satellite data on the previously unexplored territory of the Tomsk agglomeration with the prospect of moving to the scale of the entire state in the future. In this study, the authors present an algorithm implemented in Python to quantify the change in the area of vegetation in an urban agglomeration using Landsat multispectral data. The tool allows you to read space images, calculate spectral indices (NDVI, UI, NDWI), and perform statistical processing of interpretation results. The created tool was applied to study the dynamics of vegetation within the Tomsk urban agglomeration during the period 1990–2022. Key findings and conclusions: (1) The non-forest areas increased from 1990 to 1999 and from 2013 to 2022. It is very likely that this is due to the deterioration of the standard of living in the country during these periods. The first time interval corresponds to the post-Soviet period and the devastation in the economy in the 1990s. The second period corresponds to the implementation and strengthening of sanctions pressure on the Russian Federation. (2) The area of territories inhabited by people has been steadily falling since 1990. This is due to the destruction of collective agriculture in the Russian Federation and the outflow of the population from the surrounding rural settlements to Tomsk and Seversk. [ABSTRACT FROM AUTHOR]

Climate warming is leading to permafrost thaw in northern peatlands, and current predictions suggest that thawing will drive greater surface wetness and an increase in methane emissions. Hydrology largely drives peatland vegetation composition, which is a key element in peatland functioning and thus in carbon dynamics. These processes are expected to change. Peatland carbon accumulation is determined by the balance between plant production and peat decomposition. But both processes are expected to accelerate in northern peatlands due to warming, leading to uncertainty in future peatland carbon budgets. Here, we compile a dataset of vegetation changes and apparent carbon accumulation data reconstructed from 33 peat cores collected from 16 sub‐arctic peatlands in Fennoscandia and European Russia. The data cover the past two millennia that has undergone prominent changes in climate and a notable increase in annual temperatures toward present times. We show a pattern where European sub‐Arctic peatland microhabitats have undergone a habitat change where currently drier habitats dominated by Sphagnum mosses replaced wetter sedge‐dominated vegetation and these new habitats have remained relatively stable over the recent decades. Our results suggest an alternative future pathway where sub‐arctic peatlands may at least partly sustain dry vegetation and enhance the carbon sink capacity of northern peatlands. [ABSTRACT FROM AUTHOR]

The effective monitoring of boreal and tundra vegetation at different scales and environmental management at latitudes above 50 degrees North relies heavily on remote sensing. The vastness, remoteness and, in the case of Russia, the difficulty of access to boreal–tundra vegetation make it an ideal technique for vegetation monitoring in the Kola peninsula, located predominantly beyond the Arctic circle in the European part of Russia. Since the 1930s, this area has been highly urbanised and exposed to strong influence by a number of different types of human impact, such as toxic pollutions, fires, mineral excavation, grazing, logging, etc. Extensive open archives of remote sensing imagery as well as recent advances in machine learning further enable the efficient use of remote sensing methods for assessing land cover changes. Here, we present the results of mapping northern vegetation land cover and changes in it over a large territory, in time and under human impact based on remote imagery from Landsat TM, ETM+ and OLI. We study the area of about 37,000 km 2 located in the central part of the Kola peninsula in the boreal, pre-tundra and tundra between 1985 and 2021 with a time interval of approximately 5 years and confirm the correlations between the human pressure and the level of vegetation changes. We put those into the perspective of year-on-year changes in the temperature and precipitation regimes and describe the recovery of the damaged original boreal vegetation (dominated by spruce) through pine and deciduous vegetation. As a by-product of this study, we develop and test an approach for the semi-automated processing and classification of Landsat images using the novel TensorFlow machine learning technique (widely spread across other disciplines) that enables high-throughput classification, even on conventional hardware. [ABSTRACT FROM AUTHOR]

Here, we present a palaeoecological study from the Valdai Hills to examine the Holocene dynamics of forest and lake ecosystems as apparent from the isolated Lake Chernoye, which developed on an island within the greater Lake Seliger middle of the East European Plain, Russia. Palaeobotanical (plant macrofossils and pollen), geochemical and quartz grains analyses, complemented with radiocarbon dating, were carried out on a 370-cm-long sediment core. Our study involves a period between ca. 11,000 and 2100 cal. yr BP, with four main results: (1) The development of Lake Chernoye began in ca. 11,000 cal. yr BP, after the melting of buried dead-ice blocks intensified by the Early Holocene warming. As pioneer plants, Chara sp., Isöetes and C. demersum, appeared in the water with a high Ca and Mg content. High values of Pinus, Artemisia, Betula nana and Chenopodiaceae pollen may indicate the remains of cold flora that have occurred in the Younger Drays in this region. (2) Between 8000 and 6500 cal. yr BP, water level decreased as apparent from a sediment hiatus. This may be connected with the Holocene thermal maximum and final melting of the buried dead-ice block. Lower water level at that time is documented by the spreading of Najas marina, N. flexilis and Potamogeton pusillus, which are all submerged plants growing in eutrophic shallow water. Significant changes in the forest ecosystem also took place in this time frame: an increase of Quercus, Corylus and Alnus was accompanied by a decrease of Pinus. (3) A decrease in deciduous tree pollen (Ulmus, Quercus, Tilia) and an increase in coniferous tree pollen (Picea and Pinus) at ca. 4200 cal. yr BP and ca. 2700 cal. yr BP are associated with the climate cooling documented by multiproxy records in many sites in Europe. (4) Location of the lake on the isolated island did not lead to different vegetation pattern development, since this latter is similar to the other sites in the East European Plain. [ABSTRACT FROM AUTHOR]

We present a reconstruction of vegetation dynamics and fire history from the western part of the Putorana Plateau during the Late-Holocene. The study area is located in the remote and poorly investigated region of Central Siberia, which represents an important area for understanding climate and environmental changes in the Russian Subarctic. Pollen and macroscopic charcoal data from three closely located lakes along an altitudinal transect in the Khantaika River basin show no major changes in vegetation in the study area during the last 3.9 ka BP. However, a detailed analysis of the data reveals an extension of forest coverage in lake catchments at about 3.1 ka BP followed by a gradual degradation of woodlands, and an expansion of shrubs and tundra vegetation at around 2.7–2.5 ka BP. Fire activity was relatively high between 3.0 and 2.0 ka BP compared to all but the most modern part of the record, while macroscopic charcoal accumulation reaches a maximum in the most recent surface sediments. This suggests an increase in the frequency and area of fires in the region since the end of the 19th century, which has no analog during the Late-Holocene. [ABSTRACT FROM AUTHOR]

Rainfall and temperature are the key factors responsible for vegetation condition, health and growth. This research work analysis spatiotemporal phenomena in between SPI, LST and VIs in summer session from 2000 to 2018 in European Russia. This study used MODIS, NDVI, LST and TRMM data. The negative SPI values represent increasing drought events with reducing rainfall and vice-versa. Numerical consequences specify that mean annual rainfall, VIs variate according to SPI values and they completely change in the year 2004, 2009 and 2015. VIs also indirectly related to LST as high LST values (high temperature) associated with low VIs values (low vegetation) and vice-versa, with correlation coefficients 0.90. Correlation analysis of VIs, SPI and LST indicate close relationship in between vegetation, rainfall and temperature and this relationship can be used for near real time vegetation drought dynamics monitoring through satellite data for short term to long term changes in vegetation growth. [ABSTRACT FROM AUTHOR]

The aim of this study is to identify the ecological and phytocenotic features and factors of differentiation of plant communities with Heracleum sosnowskyi Manden. in the Kursk region. This region is located on the southern border of the secondary area of this species in European Russia. Plant communities with Heracleum sosnowskyi in the study area are represented by four syntaxons. To identify the ecological patterns of their organization, we used an analysis of the composition of differential species and species with the greatest activity, the identification of differences in the ecological regimes of their habitats, and the ordination analysis of relevés. Each syntaxon differs from the others in a number of environmental factors and is characterized by a group of species with similar environmental requirements. The predominance of ruderal and eurytopic species in communities and an increase in similarity of their floristic composition are manifestations of the negative impact of the distribution of Heracleum sosnowskyi on the vegetation cover. The greatest similarity of coenofloras is found between the derivative communities Heracleum sosnowskyi [Agropyretalia intermedio-repentis] and the association Urtico dioicae-Heracleetum sosnowskyi. Their phytocoenoses represent successive stages of a change in vegetation cover under the influence of the invader. As a result of the spread of hogweed, the strongest changes occurred in aboriginal communities, in place of which the phytocenoses of these syntaxons were formed. In communities where Heracleum sosnowskyi forms variants of associations Rudbeckio laciniatae-Solidaginetum canadensis and Chelidonio-Aceretum negundi, the floristic composition and ecological conditions changed slightly compared to typical communities of these syntaxons due to the presence of other invasive species. [ABSTRACT FROM AUTHOR]

Biological diversity is the basis for, and an indicator of biosphere integrity. Together with climate change, its loss is one of the two most important planetary boundaries. A halt in biodiversity loss is one of the UN Sustainable Development Goals. Current changes in biodiversity in the vast landmass of Siberia are at an initial stage of inventory, even though the Siberian environment is experiencing rapid climate change, weather extremes and transformation of land use and management. Biodiversity changes affect traditional land use by Indigenous People and multiple ecosystem services with implications for local and national economies. Here we review and analyse a large number of scientific publications, which are little known outside Russia, and we provide insights into Siberian biodiversity issues for the wider international research community. Case studies are presented on biodiversity changes for insect pests, fish, amphibians and reptiles, birds, mammals and steppe vegetation, and we discuss their causes and consequences. [ABSTRACT FROM AUTHOR]

This study presents the first centennial‐scale multi‐proxy record from the East Sayan Mountains, which are part of the central Asian 'water tower' massif. The record from Lake Kaskadnoe in the Jom‐Bolok area shows changes in vegetation and climate since c. 14.2 cal. ka BP. Although the study site is in an area with active volcanism, there is no clear evidence that volcanic eruptions influenced the local vegetation. At c. 14.2–12.9 cal. ka BP, regional climate was sufficiently warm and moist to allow scattered growth of Picea, Larix and Betula nana around the lake. A cooling episode at c. 12.9–11.5 cal. ka BP is coincident with the Younger Dryas and led to the predominance of shrub tundra in the basin. Cool and moist conditions c. 11.5–9.0 cal. ka BP resulted in the spread of Pinus sibirica in the catchment of Lake Kaskadnoe. The Middle Holocene, c. 9.0–4.5 cal. ka BP, featured a warmer and drier regional climate, which led to a decrease in high‐elevation dark conifer forest. Subsequently, the onset of the Neoglacial and a cooler climate is indicated by the spread of Larix sibirica and Pinus sibirica in the study area. Lateglacial and Holocene moisture conditions in the East Sayan Mountains have primarily been controlled by the interaction of the westerlies and the East Asian Summer Monsoon and show a drying trend through time; long‐term insolation changes affected both the Monsoon and regional temperatures. The pattern of moisture decrease in the latter part of the Holocene is seen at sites in adjacent regions of the central Asian mountains. [ABSTRACT FROM AUTHOR]

The problems of diagnostics of the beginning of agrarian development of coniferous–broad-leaved forests in northwestern European Russia and its specificity regarding changes in the zonal forest cover and its anthropogenic modifications inherent in the forest and field-meadow landscape based on studying pollen spectra from key sections. It was established that the onset of the agrarian development of the forests in the region under consideration dates back to 2300–2600 cal years BP. Judging by the continuous presence of cultivated plant pollen in the diagrams, it becomes ubiquitous and irreversible after 1500 cal years BP. The corresponding indicators and plants are given. The presence of plant pollen grains in the diagrams makes it possible to establish the time and nature of agrogenic changes in the vegetation composition. [ABSTRACT FROM AUTHOR]

This paper presents two new pollen records and quantitative climate reconstructions from northern Chukotka documenting environmental changes over the last 27.9 ka. Open tundra‐ and steppe‐like habitats dominated between 27.9 and 18.7 cal. ka BP. Betula and Alnus shrubs might have grown in sheltered microhabitats but disappeared after 18.7 cal. ka BP. Although the climate was rather harsh, local herb‐dominated communities supported herbivores as is evident by the presence of coprophilous spores in the sediments. The increase in Salix and Cyperaceae ~16.1 cal. ka BP suggests climate amelioration. Shrub Betula appeared ~15.9 cal. ka BP, and became dominant after ~15.52 cal. ka BP, whilst typical steppe communities drastically reduced. Very high presence of Botryococcus in the Lateglacial sediments reflects widespread shallow habitats, probably due to lake level increase. Shrub Alnus became common after ~13 cal. ka BP reflecting further climate amelioration. Simultaneously, herb communities gradually decreased in the vegetation reaching a minimum ~11.8 cal. ka BP. A gradual decrease of algae remains suggests a reduction of shallow‐water habitats. Shrubby and graminoid tundra was dominant ~11.8–11.1 cal. ka BP, later Salix stands significantly decreased. The forest‐tundra ecotone established in the Early Holocene, shortly after 11.1 cal. ka BP. Low contents of green algae in the Early Holocene sediments likely reflect deeper aquatic conditions. The most favourable climate conditions were between ~10.6 and 7 cal. ka BP. Vegetation became similar to the modern after ~7 cal. ka BP but Pinus pumila came to the Ilirney area at about 1.2 cal. ka BP. It is important to emphasize that the study area provided refugia for Betula and Alnus during MIS 2. It is also notable that our records do not reflect evidence of Younger Dryas cooling, which is inconsistent with some regional environmental records but in good accordance with some others. [ABSTRACT FROM AUTHOR]

The Cretaceous fossil flora in deposits of the Okhotsk–Chukotka volcanic belt is drastically different in systematic composition from the paleoflora of similar ages in deposits of the Northeast Asian coastal lowlands and inland depressions. In the volcanic burials, paleoflora features are the most evident in the Chaun flora found in the Pegtymel trough in the Central Chukotka region and described in the monograph by L.B. Golovneva "The Chaun Flora of the Okhotsk–Chukotka Volcanic Belt." Based on these data and our own experience in studying the Okhotsk–Chukotka belt stratigraphy and the vegetation cover dynamics in the Kamchatka recent volcanism area, we have proven that the Chaun flora was formed not on the volcanic highlands, as Golovneva stated, but on the lowlands, on a periodically renewed juvenile surface of the central part of the vast volcanic field separately from the background diaspora sources. This flora is not characterized by a clear lateral and stratigraphic confinement, because the characteristic plant fossils can be found in deposits of different ages throughout the volcanic belt. They are indicative of particular vegetation and burying conditions in the surface volcanism from the Turonian to the Campanian inclusive. [ABSTRACT FROM AUTHOR]

Paleogene vegetation changes in Primorye (Far East of Russia) are studied using the Plant Functional Types (PFT) Approach, for the first time applied on the large palaeobotanical records of this region. The palaeobotanical data for this reconstruction are based on the analysis of 30 palynofloras and 24 leaf floras covering the Early Palaeocene to Late Oligocene. The vegetation reconstruction at the level of PFTs in general points to the presence of mesophytic forest vegetation in Primorye throughout the Paleogene. While in the Palaeocene vegetation of Primorye was of temperate deciduous type, warm temperate‐mixed evergreen‐deciduous forests dominated in the Eocene and Early Oligocene. In the Late Oligocene, the vegetation of Primorye was again primarily deciduous, mixed evergreen‐deciduous forests persisted at places. The observed vegetation patterns and their changes through time in many cases can be correlated with spatial climate patterns and the overall continental palaeoclimate evolution, as recently reconstructed from the same palaeobotanical record. The higher‐than‐present spatial homogeneity of Paleogene vegetation coincides with shallow temperature gradients and a significantly more humid regional rainfall pattern over Primorye during the Paleogene. [ABSTRACT FROM AUTHOR]

Questions: Have species richness and composition in subarctic vegetation changed over the past ca. 90 years? Are compositional shifts linked to changes in land management or climate? Are observed changes associated with vegetation type, life form, or habitat preference? Location: Rybachy and Sredny Peninsulas, NW Russia. Methods: We resurveyed vegetation ca. 90 years after the first sampling in 1927–1930 to study changes in species richness, abundance and composition. Because of missing plot‐related environmental measurements we used a weighted averaging approach calculating relative changes in species‐specific optimum values for different environmental gradients represented by species indicator values to identify compositional change in relation to the environment. Changes in species composition were visualised using detrended correspondence analyses. Significances of observed changes in species richness and frequency were evaluated using restricted permutation tests. A χ2 test was used to test if observed changes in abundances were related to species' life form and habitat preferences. Results: Species composition has changed significantly over the past ca. 90 years, as indicated by significant changes in species' frequencies and values of optima for the environmental gradients temperature, moisture, nutrients and light. Species richness decreased significantly, in particular in nitrophilous and wet growing vegetation. Species typical for grazed grasslands and meadows and species of wet habitats became less abundant, while dwarf shrubs and forest species increased. Conclusions: Land abandonment, in combination with climate change, is likely to have caused the observed changes in the subarctic vegetation of NW Russia. Shifts in the species dominance ratios and interspecific competition (e.g. for reallocated nutrients) after land abandonment may have been promoted by the subsequent change towards a warmer climate, facilitating the regrowth of previously open meadows with grazing‐intolerant tall herbs, forest herbs and dwarf shrubs. This study illustrates clearly the long‐term effects of land‐use change, the consequences of which are still visible even after almost one century in the subarctic. [ABSTRACT FROM AUTHOR]

Aim: Documenting past vegetation dynamics and fire‐vegetation relationships at a regional scale is necessary to understand the mechanisms that control the functioning of the boreal forest, which is particularly sensitive to climate change. The objective of this study is to document these interactions in the Komi Republic during the Holocene. Location: Yaksha, Vychegda river basin, Republic of Komi, Russia. Taxon: Plantae, gymnosperms, angiosperms. Methods: Two palaeoecological approaches are combined, based (1) on pollen (this study) and charcoal analysis (recomputed from our previous analysis) applied to cores from two peatlands and (2) on a REVEALS model (a part of the Landscape Reconstruction Algorithm "LRA") applied to six regional pollen cores in order to obtain a regional estimate of vegetation cover during the Holocene. Results: The pollen diagram produced locally from Yaksha was compared with the regional vegetation cover determined by REVEALS. Taxa such as Abies sp. and Pinus spp. showed differences between the two approaches, but vegetation signals remain qualitatively consistent. From 10,000 to 6,000 cal. yr BP, the forest was mainly a light taiga (composed of Pinus sylvestris and Betula spp.) and low fire activity was recorded. From 6,000 to 3,500 cal. yr BP, a dark taiga (composed of Picea spp., Abies sibirica and Pinus sibirica) was established due to favourable climatic conditions, despite higher fire activity. From 3,500 cal. yr BP onwards, the continuous increase in fire activity allowed for a gradual return of light taiga, Betula spp., likely reinforced by human activities. The dynamics of Picea spp. and Abies sp. were asynchronous between the sites. For Picea spp., the hypothesis of local inter‐site expansion distributed along stream corridors is supported by the data. For Abies sp., a bias in REVEALS, and in climate cooling may explain disparities between sites. Main conclusions: We found evidence that in the early and mid‐Holocene, vegetation dynamics were probably more influenced by climate, as fire activity was low. During the late Holocene, fire activity and geomorphology, eventually augmented by human activities, increased in influence on vegetation dynamics and led to the predominance of the light taiga forest up to the present. [ABSTRACT FROM AUTHOR]

Shrub expansion into arctic and alpine tundra is one of the prominent vegetation changes currently underway. We studied the expansion of shrub vegetation into high elevation tundra in the Kvarkush Range of the Northern Ural mountains, Russia. Age structure analysis of the dominant shrub Juniperus sibirica Burgsd. seems to support ongoing upslope advance of shrubs, a process particularly active in the second half of the 20th century. We found a close connection between the expansion of shrub vegetation and the general change in climatic conditions of the cold season (months with mean air temperature below 0°C from November to March). In general, the greatest influence on the distribution of J. sibirica is exerted by the climate conditions of the beginning (November–January) and the end (March) of the cold season. With increasing elevation, the correlation coefficients between the establishment of J. sibirica shrubs and the precipitation of the beginning of the cold season increased, and reached maximum values at the top elevation level of the study area. However, the upwards shift of J. sibirica into typical mountain tundra does not lead to changes in the ecological structure of vegetation at this stage, but simply a decrease in the area of mountain tundra. [ABSTRACT FROM AUTHOR]

Samples from 12 drillhole-cores from the Urals-Emba region to the north-east of the Caspian Sea were analysed for pollen and spores. The records reveal vegetation and climate changes for the late Pliocene to early Pleistocene within the time interval from ca. 3.6 to ca. 1.65 Ma. According to the results of the pollen analysis, at the beginning of the Akchagylian stage (3.6–3.4 Ma) there was a cooling and change in structure of the dendroflora, and steppe-dominated landscapes were present. At the end of the early Akchagylian, and continuing into the middle Akchagylian, a maximum variety of pollen from tree species occurred. The presence of mesophilic and thermophilic elements signifies a moderately warm and humid climate occurred at around 3.2 Ma, probably related to the 'Mid-Pliocene Warm Period'. A second major cooling occurred at around 2.5 Ma coinciding with the onset of northern hemisphere glaciations. During this time, coniferous forests dominated by Picea , Pinus and Abies with lesser numbers of broad-leaved trees were established. At the end of the Akchagylian, at around 1.8 Ma, the climate became more arid and steppe landscapes were re-established. During the Akchagylian, alternations between forest- and steppe-dominated landscapes occurred at least three times in the Urals-Emba region. Results are compared with pollen spectra in surface samples, and with ostracods and foraminiferal assemblages in cores from the study region. • Pollen analyses of samples from 12 cores from the late Pliocene to early Pleistocene of the Urals-Emba region, Russia. • Detailed vegetation interpretations for the Akchagylian and Apsheronian regional stages of the northern Caspian Sea region. • Recognition of phases of steppe and forest vegetation in relation to periods of dry and humid climates. • Analysis of dendroflora of determine paleogeographic origins of Plio-Pleistocene tree taxa. • Integration of results with modern pollen, foraminifera, ostracods and regional geology. [ABSTRACT FROM AUTHOR]

There are a number of different factors that affect the sustainable development of agriculture. Efficient use of land and water resources, taking into account the threats that may arise due to climate change, as well as the dynamics of plant growth and development. Vegetation indices play an important role in monitoring vegetation variations. This article provides information on seasonal and long-term changes in the EVI (Enhanced Vegetation Index) of arable land in the Bryansk region. The purpose of the article is to discern the course of the seasonal dynamics of the index, the ranges of its variability, probable causes of differences between 2000-2018. In this article, physicochemical research methods were used to calculate the humus content, surface topography characteristics, and agricultural use features based on cartographic and stock materials, and the soil composition and density were determined through fieldwork. Summarized material on changes in EVI values for a snowless period as a whole and for individual filming intervals (18 per year) in 2000-2018 is presented. The mechanism of the influence of a variety of edaphic vegetation conditions on smoothing the differences in EVI over a series of years with different meteorological conditions has been described. The results of the analysis of the factors of the long-term dynamics are presented, the role of short-term climatic fluctuations, a progressive decrease in the amount of precipitation, and changes in the species composition of grain crops in the long-term dynamics of EVI are demonstrated. [ABSTRACT FROM AUTHOR]

The results of an analysis of the long-term series of remote sensing data from Terra/Aqua satellites (Burned Area MCD64A1 monthly product, the 6th collection) and Landsat satellites are presented to estimate the dynamics of of the vegetation cover condition caused by wildfires throughout the Russian Federation and in its individual regions. An approach to the use of remote sensing and geoinformatics methods for monitoring the impact of wildfires on the state of various types of vegetation cover without involving ground truth data is proposed. Potential for using a normalized burn ratio index to estimate the degree of vegetation damage and recovery process using low-resolution satellite data is demonstrated. It was established that the total area of burned vegatation over the country ranged from 68.40 to 234.46 thousand km2 per year for the period from 2002 till 2017. Seasonal peaks of fire activity, patterns of the spatial distribution of fire sources, and the main types of burned vegetation were identified for each of the eight federal districts of Russia. The accuracy of burned areas detection was estimated as 75–81% depending on the information product used according to the low (500 m) and average (30 m) spatial resolution data. [ABSTRACT FROM AUTHOR]

Karelia, like the entire Fennoscandian Shield, is a region with a low seismic activity. An example of the best-studied locality is a paleoseismic dislocation on Mount Vottovaara, which bears traces of disastrous Holocene geological events following the degradation of the last ice sheet. The evolution of the study area falls into three stages. At pre-Quaternary stage I, an uplifted block broken by numerous fractures and faults was formed. At glacial stage II, coarse clastic moraine was formed, the moving ice polished the crystalline basement surface and glacial scars were formed. At final deglaciation stages, the mountain top remained a nunatak. As Salpausselkä II marginal sediments retreated by about 70 km from the mountain, a postglacial stage in the region's evolution, at which an earthquake occurred, began. It could have been triggered mainly by the consequences of the degradation of the Late Weischelian glaciations such as the rapid removal of the glacial load that contributed to the rejuvenation of various old faults. Changes in paleoecological conditions for the Mount Vottovaara area were reconstructed based on the results of lithological, palynological, diatom and radiocarbon studies of bottom sediments from a small lake on the mountain top. Vegetation dynamics from the Younger Dryas to the Subboreal period is presented. Small lake evolution stages were distinguished based on analysis of diatom complexes and the pollen and spores of aquatic and aquatic-subaquatic plants and Pediastrum algae. The data obtained show that minerogenic sediments were abruptly succeeded by organic in the late Preboreal-early Boreal period. The thickness of Boreal sediments and changes in the composition of diatom complexes and spore-and-pollen spectra suggest a depositional hiatus triggered by a strong earthquake which changed the water level of the pond and its basin structure. The earthquake is also indicated by numerous dismembered, displaced, thrown-away and shifted rock blocks and seismogravity downfalls. Deflation and other types of weathering are responsible for the formation of seide-shaped piles of blocks and boulders on the mountain top. [ABSTRACT FROM AUTHOR]

The majority of fossil floras from Cretaceous volcanogenic rocks of Northeast Russia considerably differ in taxonomy from the coeval paleofloras of coastal lowlands. In order to explain the peculiarities of their formation, we used the data on the modern vegetation dynamics for volcanic plateaus of Central Kamchatka. It is shown that there was virtually no erosion where paleofloras of the Okhotsk-Chukotka volcanogenic belt, represented in the burials, existed; however, volcanogenic material, suitable for burials to form, was supplied in abundance. After massive eruptions, inner parts of the vast volcanic zone appeared to be isolated from sources of diaspores. Vegetation cover in these areas was restored mainly owing to the pool of local taxa; i.e., it was supported as a diasporic subclimax. The absence of concurrent angiosperms favored the long-term preservation of ancient taxa in these paleofloras and the appearance of new taxa on their basis. [ABSTRACT FROM AUTHOR]

Climate change and human activity considerably influenced the temperate European deciduous forests through the Holocene, with the anthropogenic impacts being detected even in currently protected areas. This paper is focused on the area of the Kaluzhskiye Zaseki Nature Reserve, which contains remnants of primary broadleaved forests in central European Russia. Here, we present a new multi-proxy record including pollen, plant macrofossils, charcoal, loss on ignition and radiocarbon dating from the Mochulya peatland supplemented by 14 radiocarbon dates of charcoal fragments from soil pits in the study area. The results show that Mochulya peatland was a fen throughout the most of the time it existed. During the last 4200 cal yr BP the study area was occupied by broadleaved forests of Quercus, Ulmus, and Tilia. Picea became relatively abundant after 2300 cal yr BP. Despite the long-term human impact, vegetation fragments of these forests have persisted in the area until the present. Three main periods of deforestation and frequent fires were identified: 3700–3200 cal yr BP, 2000–1600 cal yr BP (the Early Iron Age) and 1000–400 cal yr BP (the Medieval Period). Whereas human-induced vegetation changes were apparent during the last two periods, vegetation dynamics during 3700–3200 cal yr BP were likely caused, at least in part, by climatic factors. [ABSTRACT FROM AUTHOR]

The new pollen record from the upper 12.75 m of a sediment core obtained in Lake Ladoga documents regional vegetation and climate changes in northwestern Russia over the last 13.9 cal. ka. The Lateglacial chronostratigraphy is based on varve chronology, while the Holocene stratigraphy is based on AMS14C and OSL dates, supported by comparison with regional pollen records. During the Lateglacial (c. 13.9–11.2 cal. ka BP), the Lake Ladoga region experienced several climatic fluctuations as reflected in vegetation changes. Shrub and grass communities dominated between c. 13.9 and 13.2 cal. ka BP. The increase in Picea pollen at c. 13.2 cal. ka BP probably reflects the appearance of spruce in the southern Ladoga region at the beginning of the Allerød interstadial. After c. 12.6 cal. ka BP, the Younger Dryas cooling caused a significant decrease in spruce and increase in Artemisia with other herbs, indicative of tundra‐ and steppe‐like vegetation. A sharp transition from tundra‐steppe habitats to sparse birch forests characterizes the onset of Holocene warming c. 11.2 cal. ka BP. Pine forests dominated in the region from c. 9.0 to 8.1 cal. ka BP. The most favourable climatic conditions for deciduous broad‐leaved taxa existed between c. 8.1 and 5.5 cal. ka BP. Alder experiences an abrupt increase in the local vegetation c. 7.8 cal. ka BP. The decrease in tree pollen taxa (especially Picea) and the increase in herbs (mainly Poaceae) probably reflect human activity during the last 2.2 cal. ka. Pine forests have dominated the region since that time. Secale and other Cerealia pollen as well as ruderal herbs are permanently recorded since c. 0.8 cal. ka BP. [ABSTRACT FROM AUTHOR]

Abstract Using the territory of the Orlovskoye Polesye National Park as a case study within the catchment basin of the Oka River (Mid-Russian Uplands, Oryol Region, Russia), we obtained palaeoecological data for studying response of forest landscapes within the forest-steppe ecotone to climate change and human impact through the Late Holocene. The paper presents reconstruction of environmental change on a local to regional scales based on plant macrofossil, spore-pollen and testate amoeba records from a peat core along with reconstruction of woodland coverage inferred from pollen data. Over the past 4000 years, the total woodland coverage has fluctuated insignificantly, ranging from 38 to 52%, while the structure of the forest has changed radically. Prior to 1500 cal. yr BP, both birch-pine and mixed temperate deciduous forests of oak, elm, ash and lime with Scots pine and well-developed shrub understory of hazel and alder grew in the region. The subsequent agricultural colonization of the territory led to a reduction of a broadleaved trees in forest stands since 1500 cal. yr BP. During the last few centuries, human activity largely associated with cutting/burning trees and farming favored the expansion of secondary forests dominated by birch. [ABSTRACT FROM AUTHOR]

We examine the vegetation cover of Sidorov and Gerasimov Islands in comparison with the continental shore of Tabunnaya Bay. It is found that Sidorov, Gerasimov and Bychii Islands differ from the shore area of Tabunnaya Bay in higher species diversity of lichens. Burozems of the continental hummocky terrain are characterized by an eroded shallow and strongly skeletal profile. Sidorov and Gerasimov Islands, unlike the continental shore area, distinctly show an additional phase of development of mixed (coniferous-broad-leaved) forest preceding the contemporary period; furthermore, Artemisa gmelinii associations and lime formations were of widespread occurrence in this area during cold climatic periods, while the continental shore area was the home for birch-shrub communities. [ABSTRACT FROM AUTHOR]

In order to reveal the optimal plant species for the protection of disturbed territories from erosion, two comparative experiments on the row sowing of permanent grass seeds collected in the northern regions of Russia (experiment 1) or originating from North America (experiment 2) have been arranged on the territory of the former slurry pond of the Vozeyskoe oil field (Usinsk raion, Komi Republic) dumped with a 1-m layer of sand. The sowing of grasses adapted to Northern Europe, together with the application of fertilizers on the technogenic substrate, yields the rapid formation of a closed grass cover, substrate-fixing turfing, and a mulch layer accumulating various nutrients and providing the further development of phytocenosis. [ABSTRACT FROM AUTHOR]

We analysed a 620-cm-long sediment record from Lake Kotokel located in East Siberia (Russia) for subfossil diatoms, chironomids and pollen to provide a reconstruction of the climate history of the area for the last 12.2 kyr. The subfossil records show differing time lags in their responses to climate change; diatoms and chironomids were more sensitive to climate change than the pollen record. Changes in the biogenic proxies seem related with changes in insolation, the temperature of the North Atlantic and solar activity. The chironomids Chironomus plumosus-type and Einfeldia carbonaria-type and the diatom Aulacoseira granulata were interpreted as markers of warm climate condition. The proxy records were divided into four periods (A, B, C and D) suggesting differing climate in East Siberia during the Holocene. Period D (12.2-9.5 kyr BP) at the beginning of the Holocene, according to chironomid and diatom records, was characterized by warm climate with summer temperatures close to modern. However, forest vegetation had not become fully established yet. During Period C (9.5-5.8 kyr BP), the climate seemed to gradually become colder and wetter from the beginning of Period C to 7 kyr BP. From 7 to 5.8 kyr BP, the climate seemed to remain cold, but aridity increased. Period B (5.8-1.7 kyr BP) was characterised by frequent and sharp alternations between warm and cold conditions. Unstable conditions during this time are also registered in records from Lakes Baikal, Khubsugul and various other shallow lakes of the region. Optimal warm and wet conditions seemed to occur ca. 4 kyr BP. During Period A (the last 1.5 kyr) the diatom and chironomid records show evidence of cold conditions at 1.5-1 kyr BP, but the forest vegetation did not change significantly. [ABSTRACT FROM AUTHOR]

The study summarizes the results of a long-term research on the factors influencing the structure of ungulate communities in the southern Russian Far East and Middle Urals. The effect of these factors in communities of the southern Far East is largely complicated by interspecific relationships between ungulates. The role of such relationships in the Middle Urals is less apparent, and the territorial distribution of ungulates is largely determined by anthropogenic transformation of habitats. [ABSTRACT FROM AUTHOR]

The article offers information on the impact of volcanic ashfall on the vegetation change in Kamchatka, Russia. It states that the eruption of the Severny Proryv impaired the assimilation apparatus, poisoned water-soluble components of tephra and change the air and temperature. It notes that 30 years after the eruption, poplars reach 10 meters in height and 15 centimeters in diameter.

Werner, K., Tarasov, P. E., Andreev, A. A., Müller, S., Kienast, F., Zech, M., Zech, W. & Diekmann, B. 2009: A 12.5-kyr history of vegetation dynamics and mire development with evidence of Younger Dryas larch presence in the Verkhoyansk Mountains, East Siberia, Russia. Boreas, 10.1111/j.1502-3885.2009.00116.x. ISSN 0300-9483. A 415 cm thick permafrost peat section from the Verkhoyansk Mountains was radiocarbon-dated and studied using palaeobotanical and sedimentological approaches. Accumulation of organic-rich sediment commenced in a former oxbow lake, detached from a Dyanushka River meander during the Younger Dryas stadial, at ∼12.5 kyr BP. Pollen data indicate that larch trees, shrub alder and dwarf birch were abundant in the vegetation at that time. Local presence of larch during the Younger Dryas is documented by well-preserved and radiocarbon-dated needles and cones. The early Holocene pollen assemblages reveal high percentages of Artemisia pollen, suggesting the presence of steppe-like communities around the site, possibly in response to a relatively warm and dry climate ∼11.4–11.2 kyr BP. Both pollen and plant macrofossil data demonstrate that larch woods were common in the river valley. Remains of charcoal and pollen of Epilobium indicate fire events and mark a hiatus ∼11.0–8.7 kyr BP. Changes in peat properties, C31/C27 alkane ratios and radiocarbon dates suggest that two other hiatuses occurred ∼8.2–6.9 and ∼6.7–0.6 kyr BP. Prior to 0.6 kyr BP, a major fire destroyed the mire surface. The upper 60 cm of the studied section is composed of aeolian sands modified in the uppermost part by the modern soil formation. For the first time, local growth of larch during the Younger Dryas has been verified in the western foreland of the Verkhoyansk Mountains (∼170 km south of the Arctic Circle), thus increasing our understanding of the quick reforestation of northern Eurasia by the early Holocene. [ABSTRACT FROM AUTHOR]

Abstract  A comprehensive analysis of samples from a frozen peat deposit in the upper reaches of the Khadytayakha River by palynological, carpological, entomological, and radiocarbon methods has been performed to reconstruct changes in the regional and local vegetation and climatic conditions during the Holocene. The results show that this peat deposit was formed from 8000 to 5000 years BP. During that period, the climate in the southern Yamal Peninsula was considerably warmer, and the present-day subarctic shrub tundra zone was occupied by plant communities of spruce, birch, and larch forests. [ABSTRACT FROM AUTHOR]

In this study a radiocarbon-dated pollen record from Lake Kotokel (52°47′ N, 108°07' E, 458ma.s.l.) located in southern Siberia east of Lake Baikal was used to derive quantitative characteristics of regional vegetation and climate from about 15 kyr BP (1 kyr=1000 cal. yr) until today. Quantitative reconstruction of the late glacial vegetation and climate dynamics suggests that open steppe and tundra communities predominated in the study area prior to ca. 13.5 kyr BP and again during the Younger Dryas interval, between 12.8 and 11.6 kyr BP. The pollen-based climate reconstruction suggests lower-than-present mean January (~-38°C) and July (~-12°C) temperatures and annual precipitation (~270-300 mm) values during these time intervals. Boreal woodland replaced the primarily open landscape around Kotokel three times at about 14.8-14.7 kyr BP, during the Allerød Interstadial between 13.3-12.8 kyr BP and with the onset of the Holocene interglacial between 11.5 and 10.5 kyr BP, presumably in response to a noticeable increase in precipitation, and in July and January temperatures. The maximal spread of the boreal forest (taiga) communities in the region is associated with a warmer and wetter-than-present climate (Tw~17-18°C, Tc~-19°C, Pann~500-550mm) that occurred ca. 10.8-7.3 kyr BP. During this time interval woody vegetation covered more than 50% of the area within a 21×21 km window around the lake. The pollen-based best modern analogue reconstruction suggests a decrease in woody cover percentages and in all climatic variables about 7-6.5 kyr BP. Our results demonstrate a gradual decrease in precipitation and mean January temperature towards their present-day values in the region around Lake Kotokel since that time. [ABSTRACT FROM AUTHOR]

Wildfires have major effects on forest dynamics, succession and the carbon cycle in the boreal biome. They are a significant source of carbon emissions, and current observed changes in wildfire regimes due to changes in climate could affect the balance of the boreal carbon pool. A better understanding of postwildfire vegetation dynamics in boreal forests will help predict the future role of boreal forests as a carbon sink or source. Time series of Normalized Difference Vegetation Index (NDVI) and Normalized Difference Shortwave Infrared Index (NDSWIR) derived from Moderate Resolution Imaging Spectroradiometer (MODIS) aboard the Terra satellite were used to investigate whether characteristic temporal patterns exist for stands of different ages in the Siberian boreal forests and whether their postwildfire dynamics are influenced by variables such as prewildfire vegetation cover. Two types of forests, evergreen needle-leaf (ENF) and deciduous needle-leaf (DNF), were studied by analysing a sample of 78 burned forest areas. In order to study a longer time frame, a chronosequence of burned areas of different ages was built by coupling information on location and age provided by a forest burned area database (from 1992 to 2003) to MODIS NDVI and NDSWIR time series acquired from 2001 to 2005. For each of the burned areas, an adjacent unburned control plot representing the same forest type was selected, with the aim of separating the interannual variations caused by climate from changes in NDVI and NDSWIR behaviour due to a wildfire. The results suggest that it takes more than 13 years for the temporal NDVI and NDSWIR signal to recover fully after wildfire. NDSWIR, which is associated to canopy moisture, needs a longer recovery period than NDVI, which is associated to vegetation greenness. The results also suggest that variability observed in postwildfire NDVI and NDSWIR can be explained partially by the dominant forest type: while 13 years after a fire NDVI and NDSWIR are similar for ENF and DNF, the initial impact appears to be greater on the NDVI and NDSWIR of ENF, suggesting a faster recovery by ENF. [ABSTRACT FROM AUTHOR]

Fine-scaled distribution patterns of vegetation and palynomorphs in a polygon mire in NE Siberia were studied in 31 × 31 plots of 1 m2 (vegetation) and along a transect at intervals of 1 m (palynomorphs). Pollen and non-pollen-palynomorph contents clearly reflect differences between polygon ridges and centres. For most single pollen types, however, no unambiguous relation with actual plant abundances and distribution exists. High pollen values are restricted to the immediate vicinity of the pollen sources, which is attributed to the low height of the vegetation. For several plant taxa, high pollen values were found to be restricted to particular plant specimens in the population. High values of pollen ascribed to taxa currently absent at the relevant plot show that the sampled mosses contain a pollen signal of several years. Betula exilis produces two morphologically clearly distinct pollen types. The distribution of selected non-pollen palynomorphs correlates to microrelief, moisture regime and/or trophic conditions. The study shows that single palaeo-sections from arctic peatlands should not be over-interpreted with respect to their palaeoecological value. Local vegetation types and site conditions, however, can be accurately reconstructed from the total assemblages and from combined occurrences of specific palynomorph types. [ABSTRACT FROM AUTHOR]

In order to investigate the relationship between vegetation change and fire history in the Siberian boreal forest, fossil pollen and charcoal from two lakes in central Yakutia, eastern Siberia, were analyzed. The vegetation change inferred from the pollen analysis was similar to that found in previous research in the region. Open larch forest covered this region during the late Glacial and early Holocene periods. Later, during the mid-Holocene, Scots pine expanded its range. The low levels of charcoal in the lake deposits represent surface forest fires, suggesting that the present-day surface fire regime has been taking place since at least 6,500 calibrated years before the present (cal yr BP) and that stand-replacing fire has not occurred during the Holocene. Larch and Scots pine forests, which are characterized by surface fire regimes, have been predominant since the early Holocene. [ABSTRACT FROM AUTHOR]

Abstract  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. [ABSTRACT FROM AUTHOR]

Carbon dioxide and methane fluxes were measured at a tundra site near Chokurdakh, in the lowlands of the Indigirka river in north-east Siberia. This site is one of the few stations on Russian tundra and it is different from most other tundra flux stations in its continentality. A suite of methods was applied to determine the fluxes of NEE, GPP, Reco and methane, including eddy covariance, chambers and leaf cuvettes. Net carbon dioxide fluxes were high compared with other tundra sites, with NEE=-92 gCm-2 yr-1, which is composed of an Reco=+141 gCm-2 yr-1 and GPP=-232 gCm-2 yr-1. This large carbon dioxide sink may be explained by the continental climate, that is reflected in low winter soil temperatures (-14°C), reducing the respiration rates, and short, relatively warm summers, stimulating high photosynthesis rates. Interannual variability in GPP was dominated by the frequency of light limitation (Rg<200Wm-2), whereas Reco depends most directly on soil temperature and time in the growing season, which serves as a proxy of the combined effects of active layer depth, leaf area index, soil moisture and substrate availability. The methane flux, in units of global warming potential, was +28 g C-CO2em-2 yr-1, so that the greenhouse gas balance was -64 g C-CO2em-2 yr-1. Methane fluxes depended only slightly on soil temperature and were highly sensitive to hydrological conditions and vegetation composition. [ABSTRACT FROM AUTHOR]

The present-day state of the ecosystem of the cooling reservoir of the Berezovskaya State District Power Plant (SDPP) in Krasnoyarsk Territory was assessed in the vegetation period of 2003. The structural-functional characteristics of bacterio-, phyto-, and zooplankton, zoobenthos, and ichthyofauna are considered. Heated waters are supposed to affect the morphology of zooplankters. [ABSTRACT FROM AUTHOR]

Long-term data on aquatic vegetation production in the mesotrophic Arakhlei Lake was comparatively analyzed. The results demonstrated that the production dynamics of aquatic vegetation communities depend on the water-level conditions of the lake. The data on the succession of dominant vegetation communities are given: Chara sp. and Ceratophyllum demersum → C. demersum and Lemna trisulca. At the same time, the increased proportion of C. demersum and L. trisulca pointed to an increased anthropogenic stress on the lake. [ABSTRACT FROM AUTHOR]

The 50% variation in the estimates of carbon (C) content in the forest soils of Russia at present is caused by confusion of terms and ignorance of the soil geographical representativeness in forests. The GIS-based analysis closes the gap to the estimate published earlier by Alexeyev and Birdsey (1994, p. 170). The average soil carbon density (SCD) for the 0.3 meter (m) layer of the forest soils in Russia is about 8.1 kg C m-2 the 1 m layer captures some 11.4 kg C m-2 and the 2 m layer holds nearly 12.3 kg C m-2. The mass of C is about 61.6 Pg C concentrated in the 0.3 m layer of forest soils; the 1 m layer accumulates 87.6 Pg C and the 2 m layer holds about 94.1 Pg C. The C content in soils of the forest zone is much higher for Russia. The SCD is 18.8 kg C m-2 and the soil C pool (SCP) is 223.6 Pg C in 1 m layer. Peat soils contribute a considerable portion of C to the forest zone of the country. The cold climate, permafrost and vegetation residues that are rich in recalcitrant compounds support a high accumulation rate of organic matter and associated nutrients in soils. This conservation is a mechanism to keep the production potential of the boreal ecosystems high in spite of their relatively low actual productivity in present environments. [ABSTRACT FROM AUTHOR]

Studies the regularities of the spring-autumn dynamics of the vertical distribution of phytoplankton in a forest pond located in the vicinity of Krasnoyarsk, Russia. Comparison of the species composition of phytoplankton occurring in epilimnion to that registered in hypolimnion; Distinct periods in seasonal vegetation of algae that were distinguished in terms of the character of their vertical distribution and species composition of dominants; Subdominant species occurring in epilimnion during the third period.

The vegetation history and development of three different types of lakes, lakes Valday, Kubenskoye and Vishnevskoye (northwest of the East European Plain) were reconstructed using paleolimnological techniques. Watershed vegetation demonstrates a close connection with climate fluctuations: gradual expansion of the southern broad-leaved trees to the North during the Holocene with the maximum extent during the climate optimum (8000–5000 BP); and their subsequent retreat afterwards; followed by the extension of spruce during the cold and dry Subboreal time; and dominance of pine-spruce-birch forests in the Subatlantic time. The Late Pleistocene and Holocene climate changes resulted in lake-level fluctuations and other ecosystem changes. Valday Lake was formed ca. 12,500 BP as an oligotrophic, deep water basin. The lake level decreased during the dry Boreal, then increased again during the humid Atlantic period. The large shallow Kubenskoye Lake was formerly a part of an ice margin lake, which was then separated (ca. 13,000 BP) and developed into the Sukhona Basin with an outflow to the northwest. During the Atlantic, the outflow direction changed to the east. As a result, the ancient Sukhona Lake disappeared and Kubenskoye Lake formed in its modern size and shape. Vishnevskoye Lake, on the Karelian Isthmus, was formed at the beginning of the Preboreal after the disappearance of the Baltic Ice Lake. It was flooded by waters of the Boreal Ancylus transgression of the Baltic Basin and had become a small eutrophic lake by the time. [ABSTRACT FROM AUTHOR]