Climate and Grazing Effects on the Biomass and Photosynthetic Capacity of Dominant Species in Mongolia Steppe Communities

Global climate change and grazing are the key factors affecting plant productivity in steppe regions of Mongolia. It is important to separate the impacts of these factors and to assess the contribution of each factor to the biomass of pastoral plants. Here, we studied the grazing and climate impact on biomass and functional traits in three dominant species of Mongolian steppe plant communities: Artemisia frigida Willd., Stipa krylovii Roshev., and Kochia prostrata (L.) Schrad. Both aridity and grazing significantly influenced the biomass of the studied species but the direction and scope of the changes were species-specific. Grazing had no effect on leaf mass per area (LMA), photosynthesis (

Restoration of the Soil and Vegetation in Sandy Land with Different Stages of Deflation

The aim of this work is to reveal the features of fallow sandy lands with different stages of deflation. The virgin soil-vegetation cover was the reference point: plots with light and strong deflation were compared with it. The soil deflation stages were determined by the presence or absence of layers characteristic of the backgroundsoils of the territory. The restoration of vegetation depends on the activity of wind erosion, the properties of the soils and substrata emerging on the soil surface. Studies have shown that the soil properties of deflated plots contradict the background and classical schemes of fallow land recovery. Keywords: Trasbaikalia, Barguzin Depression, sandy lands, plant-soil cover, soil deflation, vegetation restoratio

Indicators of Pasture Digression in Steppe Ecosystems of Mongolia

The research shows that widely used key measures of vegetation structure (species diversity, projected cover and above-ground phytomass) are not always suitable as indicators of pasture degradation. Based on an analysis above-ground phytomass composition, new quantitative indices are offered that give a more realistic picture of rangeland condition in Mongolia

Bush Encroachment of Forest-steppe Landscapes in the Mongolian Part of the Lake Baikal Basin

The character of competitive relationships between woody and shrub vegetation in the southern (Mongolian) part of the Lake Baikal basin was studied via model polygons. Depending on the environmental conditions, native forests are being replaced by different types of shrubs. The main factors contributing to these changesare the aridization of the climate and human activity. It is shown that the current state of shrub communities and their progressive dynamics along the southern border of boreal forests in Mongolia allow us to consider them stable cenoses, which prevent a natural renewal of coniferous (pine, larch) forests in this region. However, some shrub species may be considered indicators of ecotopes’ suitability for natural or artificial reforestation because their ecological requirements are similar to those of forest trees. Keywords: Lake Baikal basin, ecotone area, destruction of forests, bush encroachmen

Leaf traits of C3- and C4-plants indicating climatic adaptation along a latitudinal gradient in Southern Siberia and Mongolia

Increasing aridity is one of the most important trends of current climate change. Leaf functional traits suggest a substantial basis for assessing the aridity effects on vegetation. However, since plants possess diverse leaf morphology and anatomy due to different evolutionary history of taxa, the effect of aridity can hardly be revealed in a multi-species analysis. We studied leaf functional traits for 317 samples of 193 plant species in steppe and desert communities along a 1600-km latitudinal gradient in Southern Siberia (Transbaikalia, Russia) and Mongolia. We determined morphological leaf traits, quantitative anatomical parameters, physiological parameters, and photosynthetic pigments content. Different relevance of leaf traits for indication of plant response to climate has been demonstrated. The clearest changes in site-mean values along the aridity gradient were shown for leaf thickness, total chloroplast number per leaf area (Nchl/A) and total surface area of chloroplasts (Achl/A) and cells (Ames/A) per leaf area. Unlike leaf size and leaf mass per area, these quantitative mesophyll parameters related to plant photosynthetic capacity were strongly correlated with climate. We found no evidence for a decrease in sizes of mesophyll cells with aridity, but cell volume as well as chloroplast number per cell were linked with plant functional type (PFT). We revealed an increase in Nchl/A and Achl/A in desert-steppe species in comparison to steppe and forest-steppe vegetation types within each PFT of C3-plants (C3-dicot herbs, C3-dicot shrubs, C3-monocots and C3-succulents). C4-plants were generally characterized by low Achl/A and Ames/A, but had higher rate of CO2-transfer through mesophyll and chloroplast surfaces. C3- and C4-plants differed in response to aridity and showed opposite trends in changes of leaf traits along the aridity gradient. We conclude that leaf mesophyll traits contribute to important mechanism of climatic adaptation in different PFTs along a large latitudinal gradient. © 2018 Elsevier GmbHRussian Foundation for Basic Research, RFBR: АААА-А17-117072810011-1, 17-29-05019, АААА-А17-117011810036-3The authors are deeply indebted Joint Russian-Mongolian Complex Biological Expedition RAS and MAS, who supported the field observation and data collection used in this study. The analytical part of this research has been partially supported by RFBR grant 17-29-05019 , and partly by project №АААА-А17-117072810011-1 of Russian Federal Budget . The research of O.A. Anenkhonov was carried out using the framework of project № АААА-А17-117011810036-3 supported by the Russian Federal Budget

Prolonged interglacial warmth during the Last Glacial in northern Europe

Few fossil-based environmental and climate records in northern Europe are dated to Marine Isotope Stage (MIS) 5a around 80 ka BP. We here present multiple environmental and climate proxies obtained from a lake sequence of MIS 5a age in the Sokli basin (northern Finland). Pollen/spores, plant macrofossils, NPPs (e.g. green algae), bryozoa, diatoms and chironomids allowed an exceptionally detailed reconstruction of aquatic and telmatic ecosystem successions related to the development of the Sokli Ice Lake and subsequent infilling of a relatively small and shallow lake confined to the Sokli basin. A regional vegetation development typical for the early half of an interglacial is recorded by the pollen, stomata and plant macrofossil data. Reconstructions of July temperatures based on pollen assemblages suffer from a large contribution of local pollen from the lake's littoral zone. Summer temperatures reaching present-day values, inferred for the upper part of the lake sequence, however, agree with the establishment of pine-dominated boreal forest indicated by the plant fossil data. Habitat preferences also influence the climate record based on chironomids. Nevertheless, the climate optima of the predominant intermediate- to warm-water chironomid taxa suggest July temperatures exceeding present-day values by up to several degrees, in line with climate inferences from a variety of aquatic and wetland plant indicator species. The disequilibrium between regional vegetation development and warm, insolation-forced summers is also reported for Early Holocene records from northern Fennoscandia. The MIS 5a sequence is the last remaining fossil-bearing deposit in the late Quaternary basin infill at Sokli to be studied using multi-proxy evidence. A unique detailed climate record for MIS 5 is now available for formerly glaciated northern Europe. Our studies indicate that interglacial conditions persisted into MIS 5a, in agreement with data for large parts of the European mainland, shortening the Last Glacial by some 50 ka to MIS 4-2.Peer reviewe

Neuroinflammation, Mast Cells, and Glia: Dangerous Liaisons

The perspective of neuroinflammation as an epiphenomenon following neuron damage is being replaced by the awareness of glia and their importance in neural functions and disorders. Systemic inflammation generates signals that communicate with the brain and leads to changes in metabolism and behavior, with microglia assuming a pro-inflammatory phenotype. Identification of potential peripheral-to-central cellular links is thus a critical step in designing effective therapeutics. Mast cells may fulfill such a role. These resident immune cells are found close to and within peripheral nerves and in brain parenchyma/meninges, where they exercise a key role in orchestrating the inflammatory process from initiation through chronic activation. Mast cells and glia engage in crosstalk that contributes to accelerate disease progression; such interactions become exaggerated with aging and increased cell sensitivity to stress. Emerging evidence for oligodendrocytes, independent of myelin and support of axonal integrity, points to their having strong immune functions, innate immune receptor expression, and production/response to chemokines and cytokines that modulate immune responses in the central nervous system while engaging in crosstalk with microglia and astrocytes. In this review, we summarize the findings related to our understanding of the biology and cellular signaling mechanisms of neuroinflammation, with emphasis on mast cell-glia interactions

Diverging climate trends in Mongolian taiga forests influence growth and regeneration of Larix sibirica

Central and semiarid north-eastern Asia was subject to twentieth century warming far above the global average. Since forests of this region occur at their drought limit, they are particularly vulnerable to climate change. We studied the regional variations of temperature and precipitation trends and their effects on tree growth and forest regeneration in Mongolia. Tree-ring series from more than 2,300 trees of Siberian larch (Larix sibirica) collected in four regions of Mongolia’s forest zone were analyzed and related to available weather data. Climate trends underlie a remarkable regional variation leading to contrasting responses of tree growth in taiga forests even within the same mountain system. Within a distance of a few hundred kilometers (140–490 km), areas with recently reduced growth and regeneration of larch alternated with regions where these parameters remained constant or even increased. Reduced productivity could be correlated with increasing summer temperatures and decreasing precipitation; improved growth conditions were found at increasing precipitation, but constant summer temperatures. An effect of increasing winter temperatures on tree-ring width or forest regeneration was not detectable. Since declines of productivity and regeneration are more widespread in the Mongolian taiga than the opposite trend, a net loss of forests is likely to occur in the future, as strong increases in temperature and regionally differing changes in precipitation are predicted for the twenty-first century