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Thirteen species of spiders from four families were collected using pitfall traps in subnivean habitat in the foothills of Salair Mt. Range, eastern Altai Krai. Linyphiidae predominate in the material. Agroeca limnicunae (McCook, 1884), previously known from Yenisei River in Middle Siberia through Cisokhotia and Alaska to New Jersey (USA), is recorded for the first time in West Siberia and redescribed. The Euro-Uralian boreo-mountainous Maro sublestus Falconer, 1915 is recorded in West Siberia for the first time. A Trans-Palaearctic-NW Nearctic boreal species, Tibioplus diversus (L. Koch, 1879), is reported for the first time from Altai Krai. The winter active spider fauna of eastern Altai Krai consists of species which can be found as adults all year round. All collected species are illustrated.

The taiga vegetation in Western Siberia has been seriously threatened by climate warming in recent decades. However, how vegetation in different growing states and climate conditions responds to climate changes differently is still unclear. Here we explore the vegetation activity trends in Western Siberia taiga forests using the annual rate of change in leaf area index (LAI) during 1982–2018 so as to answer two questions: (1) how did climate warming affect taiga vegetation activity in the recent last decades? (2) Did the growing state of taiga forest affect its response to climate warming? Our results revealed that climate warming promoted taiga vegetation activity in Western Siberia before 2000. However, continuous warming caused excessive evapotranspiration and led to decreased vegetation activity after 2000. Moreover, the intensity of vegetation growth response to warming was positively related to canopy height and LAI, indicating that both the positive and negative effects of warming were more significant in taiga forests in better growing state. Since these forests generally have higher productivity and play more important roles in ecosystem functioning (e.g., carbon sink and biodiversity conservation), our results highlight their vulnerability to future climate change that need more research attention. [ABSTRACT FROM AUTHOR]

Fire is a crucial disturbance factor for the structure and function of forest ecosystems, as it directly or indirectly affects plant growth, animal life and soil biogeochemical properties. Here, the effects of different fire severities and key driving environmental factors on soil microbial diversity and biomass were investigated in taiga forests that had undergone light, moderate or heavy fires, more recently or in the past, with unburned taiga forest included as a control (CK). The sample sites were located in the Greater Khingan mountains in the northeast of China. Critical soil parameters were determined, and bacterial and fungal content was inferred from determined phospholipid fatty acids (TPLFAs). The results showed that (1) all three fire severities significantly increased the concentrations of soil microbial carbon (MBC), moisture content (MC) and total nitrogen content (TN), but they significantly decreased soil available potassium (AK) content compared with the CK. (2) Recent light and moderate fires significantly decreased the Simpson and Shannon indices of soil microbial communities compared to CK; moderate fire did not change the Menhinick and Margalef indices. (3) Following moderate fire disturbance, there were no significant differences (p > 0.05) in relative abundance of total soil bacteria (Ba), Gram-positive bacteria (G+), Gram-negative bacteria (G−) and content of TPLFAs compared to the control, either as a result of more recent fires or earlier fires. (4) Redundancy analysis revealed that soil MC, TN, soil organic carbon (SOC), available P (AP) and alkaline N (AN) all strongly significantly affected the composition of the microbial communities, with a total explanation of 85.16% of the data. The species diversity and biomass of Ba, G+, G− and TPLFAs were in accordance with the intermediate disturbance hypothesis. The change pattern of soil fungi was in accordance with their own characteristics of reproduction and growth, which was in line with k-selection and ecological countermeasures. [ABSTRACT FROM AUTHOR]

This study was carried out in the territories of Northern Europe, in the middle taiga subzone of Karelia. The paper presents the results of a study of an experiment on logging to study the impact of controlled logging using supervised logging with controlling cutting (SLCC) and conventional logging (CL) on the properties of soils (horizons O, E and BF) in a spruce forest 15 years after logging. Virgin forest (VF) was used as a control. The volume weight of soils, the contents of carbon, nitrogen and potassium in different soil layers (layers O, E and BF), as well as reserves of C, N and K and their stratification coefficients SRs (SR1 [O:E], SR2 [O:BF] and SR3 [E:BF]) were studied. The results showed a tendency to increase the volume weight of soils of anthropogenically disturbed (CL and SLCC) areas can be measured. The obtained data demonstrated that there was no sharp change in the contents or stocks of the studied elements between the anthropogenically disturbed (CL and SLCC) and undisturbed areas (VF). The largest reserves of carbon, nitrogen and potassium were noted in the upper horizons of the soils of all sites, averaging 35.6, 1.27 and 0.073 t/ha, respectively. In the lower horizons of the studied soils, the values were lower. The values of the stratification coefficients in the studied soils were arranged in decreasing order as SR2 > SR1 > SR3. At the same time, the general trend of unidirectional changes in the SR values for carbon and potassium in soils was noted; the data for nitrogen were somewhat different. The results showed a marked decrease in SOC concentration with an increase in soil depth. Higher rates of cellulose decomposition were observed in anthropogenically disturbed areas (CL—69.0 ± 3.6%; SLCC—57.4 ± 3.5%) compared with virgin forest (VF) (53.7 ± 3.1%), which is consistent with the results of other studies in the taiga zone. The data obtained indicate the importance of a more accurate assessment of the contents and stocks of elements, as well as the need to use tests for soil biological activity. [ABSTRACT FROM AUTHOR]

Plant-microbe interactions play a crucial role in maintaining biodiversity and ecological services in boreal forest biomes. Mining for minerals, and especially the emission of heavy metal-enriched dust from mine sites, is a potential threat to biodiversity in offsite landscapes. Understanding the impacts of mining on surrounding phyllosphere microbiota is especially lacking. To investigate this, we characterized bacterial and fungal communities in the phyllosphere of feather moss Pleurozium schreberi (Brid). Mitt in boreal landscapes near six gold mine sites at different stages of the mine lifecycle. We found that (1) both mining stage and ecosystem type are drivers of the phyllosphere microbial community structure in mine offsite landscapes; (2) Bacterial alpha diversity is more sensitive than fungal alpha diversity to mining stage, while beta diversity of both groups is impacted; (3) mixed and deciduous forests have a higher alpha diversity and a distinct microbial community structure when compared to coniferous and open canopy ecosystems; (4) the strongest effects are detectable within 0.2 km from operating mines. These results confirmed the presence of offsite effects of mine sites on the phyllosphere microbiota in boreal forests, as well as identified mining stage and ecosystem type as drivers of these effects. Furthermore, the footprint was quantified at 0.2 km, providing a reference distance within which mining companies and policy makers should pay more attention during ecological assessment and for the development of mitigation strategies. Further studies are needed to assess how these offsite effects of mines affect the functioning of boreal ecosystems. [ABSTRACT FROM AUTHOR]

Abstract Background Being the product of the same environment, soil and vegetation are mutually associated with each other, but the relationships between edaphic properties and vegetation characteristics are still far from clear. Accordingly, the specific aim of this study is to identify relationships between forest site types/forest types and the fertility of soil organic horizons in northwestern Russia. The relationships were assessed at the level of three large forest regions, the northern and middle taiga of the Republic of Karelia, and the Karelian Isthmus (Leningrad region), based on 37 spruce, 66 pine, and 16 birch plots which were integrated with the International Cooperative Programme on Assessment and Monitoring of Air Pollution Effects on Forests (ICP Forests). Results Soil forming rock and land-use history partly explain the differences in the fertility of soil organic horizons between the forest ecosystems in northwestern Russia. Climatic factors are closely correlated with plant species richness, density and the fertility of soil organic horizons. Nutrient content in the organic horizons increased from poor to rich site types identified according to composition of understory vegetation and the occurrence of certain indicator species, i.e. Cajander’s forest site types. The most informative parameters in explaining differences between Cajander’s types were nitrogen, carbon to nitrogen ratio, exchangeable calcium, magnesium, potassium, and base saturation. Extractable phosphorus, carbon to nitrogen ratio, exchangeable calcium, magnesium, aluminum and base saturation were the most informative parameters in explaining differences between forest types identified within the Cajander types in accordance with the tree species composition, i.e. Sukachev’s forest types. The organic horizons of spruce and birch-dominated forests contained significantly more nutrients, compared to those dominated by pine. These differences were explained by differences in litter quality, and the crown shape and density of tree species, which affect the intensity of nutrient leaching. Conclusions The study presents new findings regarding the relationships between forest sites/types and the fertility of soil organic horizons in northwestern Russia. Differences in organic horizon’s fertility between the taiga subzones are explained by differences in the soil forming rock, climatic conditions, land-use history and shares of forest site types/forest types.

• The branch radial growth of Picea obovata is ten times more sensitive to aridity than Larix sibirica in a Taiga ecosystem. • The hydraulic distance from the bundle sheath to the stomata can predict the growth rate both within and across species. • Earlywood and latewood anatomies showed different relations to branch radial growth within and across species. • Leaf hydraulics play a pivotal role in predicting growth response to aridity within and across conifer species in Taiga ecosystem. Despite inter-specific differences in hydraulic traits at broad scale have been comprehensively studied, intra-specific hydraulic variability in situ is less well known. Which hydraulic traits can better predict whole-plant performance in field both within and across species remains largely ambiguous. In the study, we conducted a field investigation on branch radial growth, leaf and branch anatomical traits related to hydraulics, as well as leaf pressure–volume curve parameters of two dominant conifer species (Larix sibirica and Picea obovata) at four sites over an aridity gradient across the Altay Mountain range, which locates at the southern edge of Taiga ecosystem, one of the largest and the most sensitive terrestrial biomes to climate change. L. sibirica is a generalist deciduous conifer species, while P. obovata is a specialist evergreen conifer species. It was found that: 1) P. obovata showed ten times higher slope of branch radial growth (RGR branch) fitted to aridity than L. sibirica ; 2) the hydraulic distance from the bundle sheath to the stomata (D MC) can predict the growth rate both within and across species; 3) earlywood and latewood anatomies showed different relations to RGR branch within and across species; 4) leaf saturated osmotic potential (Ψ sat) but not turgor loss osmotic potential (Ψ tlp) was significantly and positively related to RGR branch within species. Our results support the hypothesis that specialists are more sensitive in growth to climate change than generalists. Further, the results highlight D MC as a pivotal role in water transport and associated carbon assimilation both within and across species in Taiga ecosystem, therefore at the core of the structural adjustments to climate change in this largest and the most sensitive terrestrial biome. [ABSTRACT FROM AUTHOR]

Abstract: A comprehensive understanding of the regional vegetation responses to long‐term climate change will help to forecast Earth system dynamics. Based on a new well‐dated pollen data set from Kanas Lake and a review on the published pollen records in and around the Altai Mountains, the regional vegetation dynamics and forcing mechanisms are discussed. In the Altai Mountains, the forest optimum occurred during 10–7 ka for the upper forest zone and the tree line decline and/or ecological shifts were caused by climatic cooling from around 7 ka. In the lower forest zone, the forest reached an optimum in the middle Holocene, and then increased openness of the forest, possibly caused by both climate cooling and human activities, took place in the late Holocene. In the lower basins or plains around the Altai Mountains, the development of protograssland or forest benefited from increasing humidity in the middle to late Holocene. [ABSTRACT FROM AUTHOR]

Through visual analysis presented in 15 tables the authors looked at the complexity of gathering as practice that not only plays a role in subsistence, but also creates meaning and frames an engagement with the environment. Gathering is studied as consisting of several processes: the searching; cleaning and sorting things, to lay out and to dry things; and transportation, consumption and packing. Objects that are gathered are shown to play important roles of mediums for people and their environment. Cases of berries, firewood, jade stones and ice are presented as illustrations of this argument. In the final part of the article gathering is studied as a metaphysical phenomenon: a process of switching from disorder to order and back. Gathering poses many metaphysical questions in a practical form, and the authors propose to look at how people deal with these questions. How does the world change for those who gather things? How do they experience this transformation? Does the human attempt to collect things become an attempt to order the chaotic environment, classify it, and contain chaos into small volumes of their bags and buckets? This study is based on social anthropological fieldwork conducted among Evenki people of East Buryatia. [ABSTRACT FROM AUTHOR]

Siberian larch (Larix sibirica) trees were studied in a drought-stressed, low-elevation Taiga forest in the Altay Mountains for their potential to be used for reconstructing precipitation. Aclimate/growth analysis provided evidence that the tree-ring widths were strongly determined by the climatic conditions from May to July, positively by precipitation and negatively by temperature. Nevertheless, the resulting regional tree-ring chronology of Siberian larch offers only a limited possibility to perform reliable reconstructions of precipitation as only 30.8% of the total variation of the actual April-July precipitation was explainable. Drought events reflected by the chronology were compared with historical records and other tree-ring derived climate reconstructions, showing some common events of climate extremes over much of Central Asia. This new Siberian larch chronology and an earlier maximum latewood density (MXD) chronology from the neighboring region reveal that the local climate is mainly characterized by cold/wet and warm/dry situations over the past 251 years. This study demonstrates that the use of both tree-ring width and MXD data may increase information of past climate variability in the Altay mountain region. [ABSTRACT FROM AUTHOR]

This study combines a literature survey and field observation data in an ad initio attempt to construct a process-based model of methane sink in upland soils including both the biological and physical aspects of the process. Comparison is drawn between the predicted sink rates and chamber measurements in several forest and grassland sites in the southern part of West Siberia. CH _4 flux, total respiration, air and soil temperature, soil moisture, pH, organic content, bulk density and solid phase density were measured during a field campaign in summer 2014. Two datasets from literature were also used for model validation. The modeled sink rates were found to be in relatively good correspondence with the values obtained in the field. Introduction of the rhizospheric methanotrophy significantly improves the match between the model and the observations. The Q _10 values of methane sink observed in the field were 1.2–1.4, which is in good agreement with the experimental results from the other studies. Based on modeling results, we also conclude that soil oxygen concentration is not a limiting factor for methane sink in upland forest and grassland ecosystems.

The response of soil respiration to warming has been poorly studied in regions at higher latitude with low precipitation. We manipulated air temperature, soil temperature and soil moisture using passive, open-top chambers (OTCs) in three different ecosystem settings in close proximity (boreal forest, riparian area, and semi-arid steppe) to investigate how environmental factors would affect soil respiration in these different ecosystems, anticipating that soil respiration would increase in response to the chamber treatment. The results indicated that OTCs significantly increased air and soil temperature in areas with open canopy and short-statured vegetation (i.e., steppe areas) but not in forest. OTCs also affected soil moisture, but the direction of change depended on the ecosystem, and the magnitude of change was highly variable. Generally, OTCs did not affect soil respiration in steppe and riparian areas. Although soil respiration was slightly greater in OTCs placed in the forest, the difference was not statistically significant. Analyses of relationships between soil respiration and environmental variables suggested that different factors controlled soil respiration in the different ecosystems. Competing effects analysis using a model selection approach and regression analyses (e.g., Q) demonstrated that soil respiration in the forest was more sensitive to warming, while soil respiration in the steppe was more sensitive to soil moisture. The differing responses and controlling factors among these neighboring forest, riparian and steppe ecosystems in Northern Mongolia highlight the importance of taking into account potential biome shifts in C cycling modeling to generate more accurate predictions of landscape-scale responses to anticipated climate change. [ABSTRACT FROM AUTHOR]

To examine the effects of frequent fires on species composition of the boreal forest in northern Mongolia, we investigated regeneration patterns, including reproductive pathways, post-fire seed sources, and site preferences, of four common tree species ( Betula platyphylla, Larix sibirica, Picea obovata, and Pinus sibirica). Regeneration patterns differed among B. platyphylla, L. sibirica, and the two evergreen conifers. B. platyphylla regenerated vigorously only after fire irrespective of the presence/absence of nearby seed sources, whereas post-fire regeneration of L. sibirica was more dependent on the presence of nearby seed sources. These two species did not regenerate in mature stands where mature trees of these species were growing. In contrast, no post-fire recruitment of P. obovata and P. sibirica was observed, whereas continuous recruitment of these species was observed in mature stands. The frequent fires that accompany illegal logging may result in larger burned areas and increase the risk of local extinctions of seed sources. The enlargement of burned areas is likely to favor post-fire recruitment of B. platyphylla. Seed dispersal limitation seems to have less effect on B. platyphylla than on the other species because of the wider seed dispersal range and vegetative reproduction capability of this species. Consequently, fires in the northern Mongolian boreal forest likely promote the relative dominance of B. platyphylla and threaten the existence of the evergreen conifers. [ABSTRACT FROM AUTHOR]

The article describes the 212 soil profiles from sub-Arctic region of Labrador, Canada. Two major soil types were found along the Churchhill River, namely, Podzols and Organic soils. It notes that Podzolic soils cover approximately 60% of the study area while the Organic soils cover 24%. The remaining percentage was classified as rock and unconsolidated material. It notes that the soil profiles were distinguished according to the Canadian System of Soil Classification.

The article deals with young people's ideas, activities and lifestyles in an Evenki village in Southern Siberia, interprets the differences of the value orders of generations in the narratives and practices in the context of the local, surrounding the society and Russia in general. Through research into youth we can get a more wholesome picture of the community. Furthermore, after the collapse of the Soviet Union the future of a society depends more and more on the new intelligentsia, the members of which have not grown up in the Soviet period. The young people living in the taiga, the edge of the civilized world, share the activities of their parents: that is, they hold on to their roots while the authorities persuade them to leave their village. The responses of the youth in relation to the desires and the possibilities are more openminded, and in these opinions the social expectations of these young people are less conformist. Different generations have different value orders. The events which have not happened in the life of young individuals do not serve as a standing-ground in life, and the activities of everyday life and the ideas are intertwined, and become the lifestyles of different generations. [ABSTRACT FROM AUTHOR]

Using an exclosure experiment in the willow stage of primary succession on the floodplain of the Tanana River, we tested the hypothesis that browsing can reduce mycorrhizal infection. We measured the effects winter browsing by moose ( Alcesalces) and snowshoe hare ( Lepusamericanus) had on mycorrhizal infection and fine root biomass of willow ( Salix spp.) and balsam poplar ( Populusbalsamifera). We found that protection from winter browsing increased ectomycorrhizal infection by 10% in the top 5 cm of the soil profile, by 23% at 5–10 cm, and by 42% at the 10–15 cm depth. Mammal browsing in taiga forests is now recognized as a major cause of the shift from palatable deciduous species such as willow and balsam poplar to less palatable species such as alder and spruce. We suggest that browsing-induced reduction in ectomycorrhizal infection of salicaceous species plays a central role in this shift in plant community composition. [ABSTRACT FROM AUTHOR]

Gap-associated spruce (Picea abies (L.) Karst.) regeneration in Sphagnum-Myrtillus stands of south taiga forests (Central Forest Biosphere reserve, Tver region, Russia) was studied to evaluate the role of different disturbances in spruce dynamics. Sampled gaps (n = 70) ranged from 40 m2 to 1.7 ha in size, and from 1 to 70 years since disturbance moment. Formation of gaps lead to increase in the number of stems per ha in all gap size classes (small: 40-200 m2 , medium: 200--3000 m2 , and large: >3000 m2gaps). Spruce was the most important species in gap refilling, although its role was not the same in different gap classes. The highest values of relative abundance (compared to other species) were recordedin small gaps, and much lower values -- in middle and large gaps. However, as refilling of gaps proceeded, spruce showed rather active regeneration in middle and large gaps and partly regained its abundancein middle-age disturbances. In general, all types of gaps studied supported spruce regeneration into the forest canopy. Almost perfect correlation between predicted outcome of spruce dynamics in gaps and its current role in the canopy of Sphagnum-Myrtillus stands suggests a good adaptation of this species to the current disturbance regime anda steady state of the these forests. (C) 1999 Elsevier Science B.V. [ABSTRACT FROM AUTHOR]