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The aim of the work was to study the effect of the azoximer bromide immunoadjuvant (polyoxidonium, PO) on certain molecular-genetic and proteomic properties of Yersinia pestis EV NIIEG strain, when added to the culture medium. Materials and methods. Y. pestis EV NIIEG was grown at 28 °C for 48 hours on LB agar pH 7.2 (Miller), with and without PO (EV+PO). Whole-genome sequencing of EV and EV+PO strains was performed on the Ion S5 XG generation II platform. Whole-genome SNP analysis and search for marker SNPs were conducted in the Wombac 2.0 program. Mass-spectra of Y. pestis EV extracts and EV+PO cells were recorded using a Microflex LT mass spectrometer. Protective properties of the test cultures were evaluated by the integral ImD50 index in BALB/c mice when infected with Y. pestis 231(708). Results and discussion. Comparative analysis has not revealed deletions, insertions and single nucleotide polymorphisms in the structure of Y. pestis EV+PO strain genome leading to a violation of the production of pathogenicity, immunogenicity and ensuring the vital activity factors of the plague pathogen. The MALDI-TOF mass spectrometry has shown that Y. pestis EV+PO strains changed the intensity of 22 % of the total number of peaks in the range of 2000–20000 Da. Most of the altered peaks in the UniProtKB protein bank belong to uncharacterized proteins and metabolic proteins. At the same time, the ImD50 was 2–3.3 times lower in cultures grown with the addition of PO than in Y. pestis EV. Thus, the addition of PO to Y. pestis EV NIIEG culture medium does not cause changes in the genes of pathogenicity and vital activity support factors of plague pathogen, but modulates its protein profile, which is accompanied by an increase in the protective potential of the EV vaccine strain.

The Pan-Eurasian Experiment Modelling Platform (PEEX-MP) is one of the key blocks of the PEEX Research Programme. The PEEX MP has more than 30 models and is directed towards seamless environmental prediction. The main focus area is the Arctic-boreal regions and China. The models used in PEEX-MP cover several main components of the Earth’s system, such as the atmosphere, hydrosphere, pedosphere and biosphere, and resolve the physical-chemical-biological processes at different spatial and temporal scales and resolutions. This paper introduces and discusses PEEX MP multi-scale modelling concept for the Earth system, online integrated, forward/inverse, and socioeconomical modelling, and other approaches with a particular focus on applications in the PEEX geographical domain. The employed high-performance computing facilities, capabilities, and PEEX dataflow for modelling results are described. Several virtual research platforms (PEEX-View, Virtual Research Environment, Web-based Atlas) for handling PEEX modelling and observational results are introduced. The overall approach allows us to understand better physical-chemical-biological processes, Earth’s system interactions and feedbacks and to provide valuable information for assessment studies on evaluating risks, impact, consequences, etc. for population, environment and climate in the PEEX domain. This work was also one of the last projects of Prof. Sergej Zilitinkevich, who passed away on 15 February 2021. Since the finalization took time, the paper was actually submitted in 2023 and we could not argue that the final paper text was agreed with him.

The aim of the work was to study the growth dependence on amino acids in Yersinia pestis strains of different phylogenetic branches of the antiqua biovar and to determine the genetic basis of auxotrophy of these strains.Materials and methods. We used 38 strains of Y. pestis, the main subspecies of the antiqua biovar, isolated in various foci of the world in the period of 1928–2020. The nutritional requirements of the strains were determined by incubation on Difco minimal agar with different sets of amino acids. Phylogenetic analysis of the strains was carried out using the Wombac 2.0 and SeaView 5.0.5 programs. Comparative analysis of the nucleotide sequences of the genes was performed using the BLAST algorithm and the Mega 7.0 program.Results and discussion. The phylogenetic appurtenance of the investigated Y. pestis strains of antiqua biovar to the phylogenetic branches 0.ANT3, 0.ANT5, 1.ANT, 2.ANT3, 3.ANT2, 4.ANT has been determined. It is established that all studied strains have a common dependence of growth on three amino acids – phenylalanine, threonine, and methionine. In the majority of the strains of antiqua biovar of all phylogenetic branches, growth is also dependent on the presence of cysteine in the medium, except for a part of the strains of the phylogenetic branch 4.ANT. In 14 genes of sulfur and cysteine metabolism, 19 mutations have been identified. Each phylogenetic group of the antique biovar has a distinct profile of mutations in genes involved in cysteine biosynthesis. The leucine requirement of the strains belonging to phylogenetic branch 0.ANT5 has been established, possibly caused by a frame shift in the leuA gene. Strains of the 1.ANT branch isolated in the Democratic Republic of the Congo demonstrate an additional proline-dependent growth. The defined nutritional requirements in the strains and the genetic causes of auxotrophy complement the phenotypic and genetic characteristics of the phylogenetic branches of the antiqua biovar and can be used as genetic markers for the differentiation of these strains.

The aim of the study was to identify structural differences in the Brucella omp25 and omp2a genes, which make it possible to determine their taxonomic position.Materials and methods. The objects of the study were the nucleotide sequences of the complete genomes of 48 Brucella strains presented in the GenBank NCBI database. To assess sequence homology, the BLAST algorithm and the MEGA 11 program were used.Results and discussion. In 13 species of Brucella and Brucella spp. with unknown species appurtenance, HindIII, EcoRV and EcoRI, AluI restriction profiles of genome regions have been reproduced in silico, including, omp25 and omp2a genes, flanked by primers 25A-25B and 2AB-2AA, respectively. In the omp25 gene, 11 non-synonymous and 24 synonymous mutations have been detected; two deletions: ∆103–108 bp – in В. nosferati, ∆562–597 bp – in В. Ovis; and ACT insertion after 585 bp – in В. vulpis. The variability of the omp2a gene in the studied Brucella strains was significantly higher. 138 SNPs have been identified, of which 60 lead to amino acid substitutions, 2 – form stop codons, and an additional deletion ∆424–561 bp – in В. abortus 1, 2, 4 biovars. Single mutations in the omp2a and omp25 genes had both group specificity – for several species, and unique – for a specific species or biovar of the pathogen. Allelic profiles of the omp25 and omp2a genes have greater resolution than their restriction profiles studied. The identified changes in the structure of the omp25 and omp2a genes correlate with the circulation of individual Brucella species and biovars in the organism of certain carriers. These genes show the presence of deletions, insertions and single polymorphic nucleotides specific to species, groups of species and, in some cases, biovars of the pathogen.

The aim of the work was to identify genotypic features of clonal complexes formed by CTX–VPI+ strains of Vibrio cholerae isolated from water bodies of the Rostov Region in different years, based on bioinformatics analysis of their whole genome sequences (WGSs).Materials and methods. Whole genome sequencing was performed on the MiSeq (Illumina) platform; identification of genetic determinants in WGSs and bioinformatics analysis – by means of BioEdit, BLASTN, BLASTP, CARD, Vector NTI software packages.Results and discussion. The strains were almost identical in each group of 2002-, 2005-, 2007-, 2020-, 2021-, and 2022-isolates and were found at different points of water sampling over a longer or shorter periods of time (from 3 weeks to 2 months). Bioinformatics analysis of WGSs of representative strains divided them into 4 clusters, which can be considered as separate clonal complexes sharing a number of characteristic genetic markers: 1) 2002-isolates containing one SNP in regulatory rpoS gene; 2) 2007-strains carrying tandemly duplicated preCTX prophage; 3) strains isolated in 2020 in Rostov-on-Don and in 2005, during epidemiological complications in the Kamensk district of the Rostov Region, which had a “hybrid” pathogenicity island including the cluster of type 3 secretion system and the nan-nag region of the VPI-2 island, and 9 SNPs in rpoS gene; 4) 2021- and 2022-strains and a single 2018-isolate containing a 9 bp deletion in vchC collagenase gene. Despite the revealed differences, representatives of all clonal complexes possessed sufficient sets of intact determinants of pathogenicity/persistence factors to realize virulent properties and ability to survive in water bodies. Detection of clonal complexes of potentially pathogenic strains in surface water bodies indicates occasional emergence of favorable conditions for their long-term circulation, which emphasizes the importance of constant monitoring of V. cholerae in the territory of Russia.

In recent decades, an increase in the number of cases of detection of the Usutu virus (Usutu, USUV, Orthoflavivirus usutuense) (family Flaviviridae, genus Orthoflavivirus) has caused great concern among medical professionals, including virologists and specialists in infectious diseases, especially since its appearance in Europe, where the pathogen caused mass birds die-off, and annually registered human cases. This review provides information about the structure of the virus and its genetic variants, geographical distribution and features of circulation in Europe and Africa, the methods and principles used to indicate and identify this pathogen, as well as the main symptoms of the disease it causes. An assessment of the environmental prerequisites for the occurrence of outbreaks of the disease caused by the Usutu virus on the territory of the Russian Federation was also carried out.

The bivalent chemical cholera vaccine is the only drug for the prevention of cholera registered in the Russian Federation. The vaccine has been produced in glass bottles containing 210 tablets. At the same time, modern trends dictate the need to produce the drug in varying dispensing and more practical packaging for the convenience of the consumer.The aim of the work was to study the stability of the properties of the immunobiological medicinal product “Bivalent chemical cholera vaccine” with modified filling and in new primary packaging.Materials and methods. When studying the quality of bivalent chemical cholera vaccine batches, physicochemical parameters, formaldehyde content, specific activity and safety, abnormal toxicity, immunogenicity, and microbiological purity were assessed. Stability in terms of “specific activity” was evaluated using dot immunoassay.Results and discussion. As a result of this work, the use of several dispensing options and new primary packaging of cholera vaccine has been experimentally substantiated. The stability of the finished vaccine preparation has been established in the “accelerated aging” test and during long-term storage. The possibility of using dot immunoassay with a conjugate based on staphylococcal protein A, labeled with colloidal gold, to monitor the stability of cholera vaccine has been experimentally demonstrated.

The acquisition of new mobile genetic elements contributes to the genetic diversity of Vibrio cholerae strains. An important role in this process belongs to the genetic material obtained from phages. The aim of this work was to identify phage-induced PLE islands in strains of V. cholerae O1 serogroup and to determine the resistance of isolates with and without those mobile genetic elements to the lytic activity of the diagnostic cholera El Tor bacteriophage. Materials and methods. Whole genomes nucleotide sequences of toxigenic and non-toxigenic V. cholerae O1 strains presented in the NCBI GenBank were used for the work. Bioinformatic analysis was performed using the BLAST algorithm, MEGA X (or BioEdit v. 7.0.9.0). The test with phages was carried out according A. Gratia technique. Results and discussion. The analysis of 39 toxigenic strains imported to the territory of the Russian Federation and neighboring countries has revealed one strain of V. cholerae O1 of the classical biovar containing the PLE5 island, and 13 strains of V. cholerae O1 of the El Tor biovar containing the PLE4 island. PLE islands have not been found in non-toxigenic strains. It is shown that strains with PLE4 belong to V. cholerae O1 genovariants of the El Tor biovar and have the ctxB1 gene allele. Isolates with this mobile element caused sporadic cases of the disease in 1994–1999, as well as cholera outbreaks in the Russian Federation (in 1993–1994, in 1998 – Dagestan, and 1993 – Tatarstan) and Ukraine (1994–1995). It has been suggested that, perhaps, the presence of the PLE4 island makes a certain contribution to the resistance of V. cholerae O1 strains of the El Tor biovar to the diagnostic cholera El Tor phage (55.6 % of phage-resistant isolates were detected), but there are other mechanisms that have not yet been identified. Thus, the data on the presence of new mobile genetic elements in the genome of earlier imported toxigenic strains of V. cholerae O1, biovar El Tor have been obtained, which expands information about their genetic organization.

Abstract Land-based mitigation is essential in reducing net carbon emissions. Yet, the attribution of carbon fluxes remains highly uncertain, in particular for the forest-rich region of Eastern Europe (incl. Western Russia). Here we integrate various data sources to show that Eastern Europe accounted for an above-ground biomass carbon sink of ~0.41 gigatons of carbon per year over the period 2010–2019, that is 78% of the entire European carbon sink. We find that this carbon sink is declining, mainly driven by changes in land use and land management, but also by increasing natural disturbances. Based on a random forest model, we show that land use and management changes are main drivers of the declining carbon sink in Eastern Europe, although soil moisture variability is also important. Specifically, the saturation effect of tree regrowth in abandoned agricultural areas, combined with increasing wood harvest removals, particularly in European Russia, contributed to the decrease in the Eastern European carbon sink.

Abstract Key message We propose a framework to derive the direct loss of aboveground carbon stocks after the 2020 wildfire in forests of the Chornobyl Exclusion Zone using optical and radar Sentinel satellite data. Carbon stocks were adequately predicted using stand-wise inventory data and local combustion factors where new field observations are impossible. Both the standalone Sentinel-1 backscatter delta (before and after fire) indicator and radar-based change model reliably predicted the associated carbon loss. Context The Chornobyl Exclusion Zone (CEZ) is a mosaic forest landscape undergoing dynamic natural disturbances. Local forests are mostly planted and have low ecosystem resilience against the negative impact of global climate and land use change. Carbon stock fluxes after wildfires in the area have not yet been quantified. However, the assessment of this and other ecosystem service flows is crucial in contaminated (both radioactively and by unexploded ordnance) landscapes of the CEZ. Aims The aim of this study was to estimate carbon stock losses resulting from the catastrophic 2020 fires in the CEZ using satellite data, as field visitations or aerial surveys are impossible due to the ongoing war. Methods The aboveground carbon stock was predicted in a wall-to-wall manner using random forest modelling based on Sentinel data (both optical and synthetic aperture radar or SAR). We modelled the carbon stock loss using the change in Sentinel-1 backscatter before and after the fire events and local combustion factors. Results Random forest models performed well (root-mean-square error (RMSE) of 22.6 MgC·ha−1 or 37% of the mean) to predict the pre-fire carbon stock. The modelled carbon loss was estimated to be 156.3 Gg C (9.8% of the carbon stock in burned forests or 1.5% at the CEZ level). The standalone SAR backscatter delta showed a higher RMSE than the modelled estimate but better systematic agreement (0.90 vs. 0.73). Scots pine (Pinus sylvestris L.)-dominated stands contributed the most to carbon stock loss, with 74% of forests burned in 2020. Conclusion The change in SAR backscatter before and after a fire event can be used as a rough proxy indicator of aboveground carbon stock loss for timely carbon map updating. The model using SAR backscatter change and backscatter values prior to wildfire is able to reliably estimate carbon emissions when on-ground monitoring is impossible.

Abstract Projections of future carbon sinks and stocks are important because they show how the world's ecosystems will respond to elevated CO2 and changes in climate. Moreover, they are crucial to inform policy decisions around emissions reductions to stay within the global warming levels identified by the Paris Agreement. However, Earth System Models from the 6th Coupled Model Intercomparison Project (CMIP6) show substantial spread in future projections—especially of the terrestrial carbon cycle, leading to a large uncertainty in our knowledge of any remaining carbon budget (RCB). Here we evaluate the global terrestrial carbon cycle projections on a region‐by‐region basis and compare the global models with regional assessments made by the REgional Carbon Cycle Assessment and Processes, Phase 2 activity. Results show that for each region, the CMIP6 multi‐model mean is generally consistent with the regional assessment, but substantial cross‐model spread exists. Nonetheless, all models perform well in some regions and no region is without some well performing models. This gives confidence that the CMIP6 models can be used to look at future changes in carbon stocks on a regional basis with appropriate model assessment and benchmarking. We find that most regions of the world remain cumulative net sources of CO2 between now and 2100 when considering the balance of fossil‐fuels and natural sinks, even under aggressive mitigation scenarios. This paper identifies strengths and weaknesses for each model in terms of its performance over a particular region including how process representation might impact those results and sets the agenda for applying stricter constraints at regional scales to reduce the uncertainty in global projections.

Abstract Production efficiency models (PEMs) are based on the theory of light use efficiency (LUE) which states that a relatively constant relationship exists between photosynthetic carbon uptake and radiation receipt at the canopy level. Challenges remain however in the application of the PEM methodology to global net primary productivity (NPP) monitoring. The objectives of this review are as follows: 1) to describe the general functioning of six PEMs (CASA; GLO-PEM; TURC; C-Fix; MOD17; and BEAMS) identified in the literature; 2) to review each model to determine potential improvements to the general PEM methodology; 3) to review the related literature on satellite-based gross primary productivity (GPP) and NPP modeling for additional possibilities for improvement; and 4) based on this review, propose items for coordinated research. This review noted a number of possibilities for improvement to the general PEM architecture - ranging from LUE to meteorological and satellite-based inputs. Current PEMs tend to treat the globe similarly in terms of physiological and meteorological factors, often ignoring unique regional aspects. Each of the existing PEMs has developed unique methods to estimate NPP and the combination of the most successful of these could lead to improvements. It may be beneficial to develop regional PEMs that can be combined under a global framework. The results of this review suggest the creation of a hybrid PEM could bring about a significant enhancement to the PEM methodology and thus terrestrial carbon flux modeling. Key items topping the PEM research agenda identified in this review include the following: LUE should not be assumed constant, but should vary by plant functional type (PFT) or photosynthetic pathway; evidence is mounting that PEMs should consider incorporating diffuse radiation; continue to pursue relationships between satellite-derived variables and LUE, GPP and autotrophic respiration (Ra); there is an urgent need for satellite-based biomass measurements to improve Ra estimation; and satellite-based soil moisture data could improve determination of soil water stress.

The aim of the work was to study the profile of antibiotic resistance of uropathogenic Escherichia coli strains isolated from patients with urinary tract infections in the urological inpatient facility of the clinical hospital in the Saratov city, depending on appurtenance to phylogenetic groups and subgroups, as well as O-serogroups.Materials and methods. We assessed sensitivity/resistance to 25 different antibacterial drugs in 102 strains of uropathogenic E. coli. The studies were carried out using the disk diffusion method. The production of extended spectrum beta-lactamases was evaluated by the double disk method. Carbapenemase output was determined using the CIM test. The PCR method was applied to determine appurtenance to phylogenetic groups and subgroups, O-serogroups, as well as the frequency of occurrence of the mcr‑1, mcr‑2, mcr‑3, mcr‑4, mcr‑5 genes encoding the proteins that mediate the development of resistance to colistin.Results and discussion. It has been established that all strains of uropathogenic E. coli are more or less resistant to antibacterial drugs. All studied 102 strains showed resistance to 23 antibacterial drugs from 8 functional groups. The resistance of uropathogenic E. coli had certain differences depending on belonging to phylogenetic groups and subgroups, O-serogroups. Strains of uropathogenic E. coli with high resistance (up to 100 %) belonged to the B23 phylogenetic group, the main representatives of which are cultures of the most common O-25 serogroup. The production of extended-spectrum beta-lactamases has been phenotypically confirmed for 69 (67.6 %) strains. No carbapenemaseproducing cultures were found in the study. The mcr‑1 and mcr‑2 genes encoding resistance to colistin have been identified in 3 uropathogenic E. coli strains (2.9 %).

The review summarizes literature data on the Vibrio cholerae secretion system of the 6th type. This system is a contact-dependent macromolecular mechanism through which bacteria translocate toxic effector proteins into target cells. It is found in many Gram-negative bacteria, including Vibrio cholerae. V. cholerae infects phagocytic amoebae, nematodes, ciliates, bacteria belonging to different species, as well as unrelated strains of V. cholerae using this system. DNA released after lysis of competing bacteria can be taken up by Vibrio cholerae cells, which leads to the acquisition of new genetic material. The type VI secretion system is involved in the infectious process. The destruction of macrophages and microbiota contributes to the active reproduction of the pathogen and colonization of host epitheliocytes, and the production of effector proteins causes the development of diarrhea and intestinal inflammation. Cholera vibrio secretion system of the 6th type has a structure similar to other gram-negative bacteria. The genes encoding the proteins of this system are located in one large region of the second chromosome and in several additional clusters. It has been shown that toxigenic strains of V. cholerae contain an identical set of secretion system genes, while their composition is variable in non-toxigenic isolates. The regulation of secretion system protein expression differs in V. cholerae strains of different toxigenicity, depends on a number of environmental signals, and is associated with other cell regulatory networks. The paper provides experimental data on the analysis of the structure of the global regulatory gene, vasH, of the type VI secretion system in toxigenic and non-toxigenic V. cholerae O1, biovar El Tor strains isolated in the Russian Federation. Thus, the type VI secretion system is an important mechanism that facilitates the survival of V. cholerae in complex communities in vitro, protects against damaging factors of the macroorganism and increases virulence in vivo, and also provides evolutionary transformations of cholera vibrio. Further study of this system will allow a better understanding of the pathogen-host interaction processes, as well as the adaptation mechanisms of V. cholerae in the external environment.

Regional land carbon budgets provide insights into the spatial distribution of the land uptake of atmospheric carbon dioxide and can be used to evaluate carbon cycle models and to define baselines for land-based additional mitigation efforts. The scientific community has been involved in providing observation-based estimates of regional carbon budgets either by downscaling atmospheric CO2 observations into surface fluxes with atmospheric inversions, by using inventories of carbon stock changes in terrestrial ecosystems, by upscaling local field observations such as flux towers with gridded climate and remote sensing fields, or by integrating data-driven or process-oriented terrestrial carbon cycle models. The first coordinated attempt to collect regional carbon budgets for nine regions covering the entire globe in the RECCAP-1 project has delivered estimates for the decade 2000–2009, but these budgets were not comparable between regions due to different definitions and component fluxes being reported or omitted. The recent recognition of lateral fluxes of carbon by human activities and rivers that connect CO2 uptake in one area with its release in another also requires better definitions and protocols to reach harmonized regional budgets that can be summed up to a globe scale and compared with the atmospheric CO2 growth rate and inversion results. In this study, using the international initiative RECCAP-2 coordinated by the Global Carbon Project, which aims to be an update to regional carbon budgets over the last 2 decades based on observations for 10 regions covering the globe with a better harmonization than the precursor project, we provide recommendations for using atmospheric inversion results to match bottom-up carbon accounting and models, and we define the different component fluxes of the net land atmosphere carbon exchange that should be reported by each research group in charge of each region. Special attention is given to lateral fluxes, inland water fluxes, and land use fluxes.

During the past several decades, the Earth system has changed significantly, especially across Northern Eurasia. Changes in the socio-economic conditions of the larger countries in the region have also resulted in a variety of regional environmental changes that can have global consequences. The Northern Eurasia Future Initiative (NEFI) has been designed as an essential continuation of the Northern Eurasia Earth Science Partnership Initiative (NEESPI), which was launched in 2004. NEESPI sought to elucidate all aspects of ongoing environmental change, to inform societies and, thus, to better prepare societies for future developments. A key principle of NEFI is that these developments must now be secured through science-based strategies co-designed with regional decision-makers to lead their societies to prosperity in the face of environmental and institutional challenges. NEESPI scientific research, data, and models have created a solid knowledge base to support the NEFI program. This paper presents the NEFI research vision consensus based on that knowledge. It provides the reader with samples of recent accomplishments in regional studies and formulates new NEFI science questions. To address these questions, nine research foci are identified and their selections are briefly justified. These foci include warming of the Arctic; changing frequency, pattern, and intensity of extreme and inclement environmental conditions; retreat of the cryosphere; changes in terrestrial water cycles; changes in the biosphere; pressures on land use; changes in infrastructure; societal actions in response to environmental change; and quantification of Northern Eurasia’s role in the global Earth system. Powerful feedbacks between the Earth and human systems in Northern Eurasia (e.g., mega-fires, droughts, depletion of the cryosphere essential for water supply, retreat of sea ice) result from past and current human activities (e.g., large-scale water withdrawals, land use, and governance change) and potentially restrict or provide new opportunities for future human activities. Therefore, we propose that integrated assessment models are needed as the final stage of global change assessment. The overarching goal of this NEFI modeling effort will enable evaluation of economic decisions in response to changing environmental conditions and justification of mitigation and adaptation efforts.

Abstract Background Assessment of the reasons for the ambiguous influence of forests on the structure of the water balance is the subject of heated debate among forest hydrologists. Influencing the components of total evaporation, forest vegetation makes a significant contribution to the process of runoff formation, but this process has specific features in different geographical zones. The issues of the influence of forest vegetation on river runoff in the zonal aspect have not been sufficiently studied. Results Based on the analysis of the dependence of river runoff on forest cover, using the example of nine catchments located in the forest-tundra, northern and middle taiga of Northern Eurasia, it is shown that the share of forest cover in the total catchment area (percentage of forest cover, FCP) has different effects on runoff formation. Numerical experiments with the developed empirical models have shown that an increase in forest cover in the catchment area in northern latitudes contributes to an increase in runoff, while in the southern direction (in the middle taiga) extensive woody cover of catchments “works” to reduce runoff. The effectiveness of geographical zonality in regards to the influence of forests on runoff is more pronounced in the forest-tundra zone than in the zones of northern and middle taiga. Conclusion The study of this problem allowed us to analyze various aspects of the hydrological role of forests, and to show that forest ecosystems, depending on environmental conditions and the spatial distribution of forest cover, can transform water regimes in different ways. Despite the fact that the process of river runoff formation is controlled by many factors, such as temperature conditions, precipitation regime, geomorphology and the presence of permafrost, the models obtained allow us to reveal general trends in the dependence of the annual river runoff on the percentage of forest cover, at the level of catchments. The results obtained are consistent with the concept of geographic determinism, which explains the contradictions that exist in assessing the hydrological role of forests in various geographical and climatic conditions. The results of the study may serve as the basis for regulation of the forest cover of northern Eurasian river basins in order to obtain the desired hydrological effect depending on environmental and economic conditions.

Abstract Since the collapse of the Soviet Union and transition to a new forest inventory system, Russia has reported almost no change in growing stock (+ 1.8%) and biomass (+ 0.6%). Yet remote sensing products indicate increased vegetation productivity, tree cover and above-ground biomass. Here, we challenge these statistics with a combination of recent National Forest Inventory and remote sensing data to provide an alternative estimate of the growing stock of Russian forests and to assess the relative changes in post-Soviet Russia. Our estimate for the year 2014 is 111 ± 1.3 × 109 m3, or 39% higher than the value in the State Forest Register. Using the last Soviet Union report as a reference, Russian forests have accumulated 1163 × 106 m3 yr-1 of growing stock between 1988–2014, which balances the net forest stock losses in tropical countries. Our estimate of the growing stock of managed forests is 94.2 × 109 m3, which corresponds to sequestration of 354 Tg C yr-1 in live biomass over 1988–2014, or 47% higher than reported in the National Greenhouse Gases Inventory.

Changes in CO2 concentration and climate are likely to alter disturbance regimes and competitive outcomes among tree species, which ultimately can result in shifts of species and biome boundaries. Such changes are already evident in high latitude forests, where waterlogged soils produced by topography, surficial geology, and permafrost are an important driver of forest dynamics. Predicting such effects under the novel conditions of the future requires models with direct and mechanistic links of abiotic drivers to growth and competition. We enhanced such a forest landscape model (PnET-Succession in LANDIS-II) to allow simulation of waterlogged soils and their effects on tree growth and competition. We formally tested how these modifications alter water balance on wetland and permafrost sites, and their effect on tree growth and competition. We applied the model to evaluate its promise for mechanistically simulating species range expansion and contraction under climate change across a latitudinal gradient in Siberian Russia. We found that higher emissions scenarios permitted range expansions that were quicker and allowed a greater diversity of invading species, especially at the highest latitudes, and that disturbance hastened range shifts by overcoming the natural inertia of established ecological communities. The primary driver of range advances to the north was altered hydrology related to thawing permafrost, followed by temperature effects on growth. Range contractions from the south (extirpations) were slower and less tied to emissions or latitude, and were driven by inability to compete with invaders, or disturbance. An important non-intuitive result was that some extant species were killed off by extreme cold events projected under climate change as greater weather extremes occurred over the next 30 years, and this had important effects on subsequent successional trajectories. The mechanistic linkages between climate and soil water dynamics in this forest landscape model produced tight links between climate inputs, physiology of vegetation, and soils at a monthly time step. The updated modeling system can produce high quality projections of climate impacts on forest species range shifts by accounting for the interacting effects of CO2 concentration, climate (including longer growing seasons), seed dispersal, disturbance, and soil hydrologic properties.

Role of jasmonate signaling in the regulation of stress-protective systems in Arabidopsis under salt stress remains insufficiently studied. For its clarification, comparative studies with mutants lacking various protein components of jasmonate signaling are advisable. In this connection, effects of methyl jasmonate (MJ, 50 μM) and salt stress (NaCl, 150 mM) on functioning of antioxidant and osmoprotective systems of wild-type Arabidopsis plants (Col-0) and ones defective in jasmonate signaling, namely coi1 (mutant for gene coding the protein COI1, which participates in removal of repressor proteins of transcription factors of jasmonate signaling) and jin1 (mutant defective in gene encoding the transcription factor JIN1/MYC2, one of the key in jasmonate signaling), were investigated. Salt stress inhibited growth of plants of all three genotypes. Treatment with MJ before salt stress positively influenced only the growth of wild-type plants. In contrast to mutants coi1 and jin1, Col-0 plants treated with MJ, under conditions of salt stress, kept close to the control values of water and total chlorophylls content, and the content of carotenoids increased. The coi1 plants under normal conditions differed from wild-type plants and jin1 mutants by reduced activity of guaiacol peroxidase and catalase and increased proline content. Treatment with MJ did not affect the activity of antioxidant enzymes and proline content in both mutants defective in jasmonate signaling. Under salt stress, the activity of superoxide dismutase, catalase and guaiacol peroxidase, as well as the content of proline and anthocyanins, in wild-type plants treated with MJ, were significantly higher than in control plants. The role of jasmonate-dependent protective systems in resistance of Arabidopsis plants to salt stress is discussed.