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seasonal variations in temperature sensitivity of soil respiration in a larch forest in the Northern Daxing’an Mountains in Northeast China

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Journal of Forestry Research 2022年第3期33卷 1061-1070页

作者： Lin Yang Qiuliang Zhang Zhongtao Ma Huijun Jin Xiaoli Chang sergey s.marchenko Valentin V.spektor College of Forestry and Da Xing’anling Forest Ecosystem Research station of Inner Mongolia Autonomous Region Inner Mongolia Agricultural UniversityHohhot010019People’s Republic of China Research-station of Permafrost Geo-Environment Ministry of EducationInstitute of Cold Regions Science and Engineering and School of Civil EngineeringNortheast Forestry UniversityHarbin150040People’s Republic of China state Key Laboratory of Frozen soils Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou730000People’s Republic of China Geophysical Institute University of Alaska FairbanksFairbanksAK99775USA Laboratory of General Geocryology Melnikov Permafrost InstituteSiberia BranchRussian Academy of SciencesYakutskRussia677010

Temperature sensitivity of respiration of forest soils is important for its responses to climate warming and for the accurate assessment of soil carbon budget. The sensitivity of temperature (T_(i)) to soil respiration rate (R_(s)), and Q_(10) defined by e^(10(lnRs−lna)/Ti) has been used extensively for indicating the sensitivity of soil respiration. The soil respiration under a larch (Larix gmelinii) forest in the northern Daxing’an Mountains, Northeast China was observed in situ from April to september, 2019 using the dynamic chamber method. Air temperatures (T_(air)), soil surface temperatures (T_(0cm)), soil temperatures at depths of 5 and 10 cm (T_(5cm) and T_(10cm), respectively), and soil-surface water vapor concentrations were monitored at the same time. The results show a significant monthly variability in soil respiration rate in the growing season (April–september). The Q_(10) at the surface and at depths of 5 and 10 cm was estimated at 5.6, 6.3, and 7.2, respectively. The Q_(10@10 cm) over the period of surface soil thawing (Q_(10@10 cm, thaw) = 36.89) were significantly higher than that of the growing season (Q_(10@10 cm, growth )= 3.82). Furthermore, the Rs in the early stage of near-surface soil thawing and in the middle of the growing season is more sensitive to changes in soil temperatures. soil temperature is thus the dominant factor for season variations in soil respiration, but rainfall is the main controller for short-term fluctuations in respiration. Thus, the higher sensitivity of soil respiration to temperature (Q_(10)) is found in the middle part of the growing season. The monthly and seasonal Q_(10) values better reflect the responsiveness of soil respiration to changes in hydrometeorology and ground freeze-thaw processes. This study may help assess the stability of the soil carbon pool and strength of carbon fluxes in the larch forested permafrost regions in the northern Daxing’an Mountains.

关键词： soil respiration Dynamic chamber method Ground thawing Major growth period soil temperature

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Impacts of degrading permafrost on streamflow in the source area of Yellow River on the Qinghai-Tibet Plateau,China

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Advances in Climate Change Research 2019年第4期10卷 225-239页

作者： MA Qiang JIN Hui-Jun Victor F.BENsE LUO Dong-Liang sergey s.marchenko stuart A.HARRIs LAN Yong-Chao state Key Laboratory of Frozen soils Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou730000China College of Resources and Environment University of Chinese Academy of SciencesBeijing100049China school of Civil Engineering Harbin Institute of TechnologyHarbin150090China Hydrology and Quantitative Water Management Group Department of Environmental SciencesWageningen UniversityWageningen6708PBthe Netherlands Geophysical Institute(GIPL) University of Alaska FairbanksFairbanks99775USA Department of Geography University of CalgaryCalgaryT3A 1E4Canada

Many observations in and model simulations for northern basins have confirmed an increased streamflow from degrading permafrost,while the streamflow has declined in the source area of the Yellow River(sAYR,above the Tanag hydrological station)on the northeastern Qinghai-Tibet Plateau,West *** and to what extent does the degrading permafrost change the flow in the sAYR?According to seasonal regimes of hydrological processes,the sAYR is divided intofour sub-basins with varied permafrost extents to detect impacts of permafrost degradation on the Yellow River *** show that permafrost degradation may have released appreciable meltwater for recharging *** potential release rate of ground-ice melt-water in the sub-basin 1(the headwater area of the Yellow River(HAYR),above the Huangheyan hydrological station)is the highest(5.6 mm per year),contributing to 14.4%of the annual Yellow River streamflow at ***/intra-and annual shifts of streamflow,a possible signal for the marked alteration of hydrological processes by permafrost degradation,is observed in the HAYR,but the shifts are minor in other sub-basins in the *** hydraulic connectivity is expected to occur during and after certain degrees of permafrost *** impacts of permafrost degradation on the annual Yellow River streamflow in the sAYR at Tanag,i.e.,from the meltwater of ground-ice,is estimated at 4.9%that of the annual Yellow River discharge at Tanag,yet with a high uncertainty,due to neglecting of the improved hydraulic connections from permafrost degradation and the flow generation conditions for the ground-ice *** evapotranspiration,substantial weakening of the southwest China Autumn Rain,and anthropogenic disturbances may largely account for the declined streamflow in the sAYR.

关键词： streamflow Warming climate Permafrost degradation streamflow patterns source area of Yellow River(sAYR)

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Impacts of climate-induced permafrost degradation on vegetation:A review

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Advances in Climate Change Research 2021年第1期12卷 29-47页

作者： JIN Xiao-Ying JIN Hui-Juna Go IWAHANA sergey smarchenko LUO Dong-Liang LI Xiao-Ying LIANG si-Hai Northeast-China Observatory and Research station of Permafrost Geological Environment(Ministry of Education) School of Civil EngineeringInstitute of Cold Region Science and TechnologyNortheast Forestry UniversityHarbin150040China state Key Laboratory of Frozen soils Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou730000China College of Resources and Environment University of Chinese Academy of SciencesBeijing100049China International Arctic Research Center University of Alaska FairbanksFairbanks99775USA Permafrost Lab Geophysical InstituteUniversity of Alaska FairbanksFairbanks99775USA school of Water Resources and Environment China University of GeosciencesBeijing100083China

Under a warming climate,degrading permafrost profoundly and extensively affects arctic and alpine ***,most existing relevant studies are more focused on the hydrothermal impacts of vegetation on the underlying permafrost,or symbiosis between vegetation and permafrost,only very few on ecological impacts of permafrost ***,there are much more pertinent investigations in arctic and boreal regions than those in alpine and high-plateau regions at mid-and low *** study emphasizes on the impact mechanisms of permafrost degradation on vegetation both at high and mid-to low latitudes,addressing vegetation succession trajectories and associated changes in soil hydrology and soil nutrient above degrading *** degradation influences vegetation by altering soil hydrology,soil biogeochemical processes and microbial communities,which further improve soil nutrient ***,under a warming climate,vegetation may take two successional trajectories,towards a wetter or drier ecosystem within a certain time period,but to a drier ecosystem in the end upon the thaw of permafrost in case of permeable soils and good ***,with rapidly developing remote-sensing and other space-and ground-based and air-borne observational networks and numerical predictive models,the impacting mechanisms of permafrost degradation on vegetation should be timely and better monitored,evaluated and modeled at desired spatiotemporal scales and resolutions by terrestrial or integrated ecosystem models.

关键词： Degrading permafrost Vegetation Impact mechanisms Climate warming Ecological impacts

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Viscous creep of ice-rich permafrost debris in a recently uncovered proglacial area in the Tianshan Mountains, China

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Advances in Climate Change Research 2022年第4期13卷 540-553页

作者： Yu ZHOU Guo-Yu LI Hui-Jun JIN sergey smarchenko Wei MA Qing-song DU Jin-Ming LI Dun CHEN state Key Laboratory of Frozen soils Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China University of Chinese Academy of sciences Beijing 100049China Da Xing'anling Observation and Research station of Frozen-ground Engineering and Environment Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesJagdaqi 165000China school of Civil Engineering and Institute of Cold Regions science and Engineering Northeast Forestry UniversityHarbin 150040China Geophysical Institute University of Alaska FairbanksFairbanksAK 99775USA

since the Little Ice Age and as a consequence of climate warming,many recently deglaciated forefields have become and will continue to evolve into large ice-debris complexes exposed to periglacial processes and *** transitional processes have significant implications for geomorphologic shaping and water supply for the downstream communities,especially in arid regions,but our understanding of their evolutionary processes and their potential geomorphic and hydrological impacts is stil limited.A landform transition from partly debris-covered glaciers to ice-rich permafrost debris undergoing slow viscous creep was revealed in the Aerzailaikunai Valley in the eastern Tianshan Mountains in China based on the results of in-situ observations and measurements(boreholes,ground temperature monitoring,electrical resistivity tomography surveys,and continuous global positioning system measurements,among others).The internal structure of ice-tll mixture contains pure ice layers,supersaturated frozen sands with ice lenses,and ice-bearing blocks with maximum volumetric contents of heterogeneous ice at 35%-60%.Beneath an 1.5-m-thick active layer,permafrost reached far into the underlying bedrock with the mean annual ground temperature of-2.1℃ at the depth of 20 *** higher surface velocities(with an accumulative displacement of 65 mm from October 2019 to May 2020)and extremely high electrical resistivity(several million Ω m)of the debris-covered glacier margin were in sharp contrast to those of the progressively stabilizing ground surface(up to 16 mm)and the lower zones with relatively smaler electrical resistivity(several thousand Ω m).Combined with the borehole stratigraphy(higher rock content),monitored ground temperatures(permafrost environment),lower electrical resistance(ice-rich moraine),and continuous global positioning system results(viscous creeping),this study documents a transition from glacial to periglacial conditions,materials and processes characteristic

关键词： Alpine permafrost Viscous creep Debris-covered glacier margins Climate warming Landform transition Evolution of rock glacier

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Advances in Climate Change Research 12(2021)48-65 Review

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Advances in Climate Change Research 2021年第1期12卷 48-65页

作者： LI Xiao-Ying JIN Hui-Jun WANG Hong-Wei sergey smarchenko sHAN Wei LUO Dong-Liang HE Rui-Xia Valentin sPEKTOR HUANG Ya-Dong LI Xin-Yu JIA Ning Key Laboratory of sustainable Forest Ecosystem Management(Ministry of Education) College of ForestryNortheast Forestry UniversityHarbin150040China Northeast-China Observatory and Research station of Permafrost Geological Environment(Ministry of Education) School of Civil EngineeringInstitute of Cold Region Science and EngineeringNortheast Forestry UniversityHarbin150040China state Key Laboratory of Frozen soils Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou730000China Permafrost Lab Geophysical InstituteUniversity of Alaska FairbanksFairbanks99775USA Melnikov Permafrost Institute Siberian BranchRussian Academy of SciencesYakutsk677010Russia school of Civil Engineering Harbin Institute of TechnologyHarbin150090China

In boreal and arctic regions,forest fires exert great influences on biogeochemical processes,hydrothermal dynamics of the active layer and near-surface permafrost,and subsequent nutrient *** this article,the studies on impacts of forest fires on the permafrost environment are *** studies indicate that forest fires could result in an irreversible degradation of permafrost,successions of boreal forests,rapid losses of soil carbon stock,and increased hazardous periglacial *** forest fires,soil temperatures rise;active layer thickens;the release of soil carbon and nitrogen enhances,and;vegetation changes from coniferous forests to broad-leaved forests,shrublands or *** may take decades or even centuries for the fire-disturbed ecosystems and permafrost environment to return to pre-fire conditions,if ever *** boreal forest,the thickness of organic layer has a key influence on changes in permafrost and *** addition,climate warming,change of vegetation,shortening of fire return intervals,and extent of fire range and increasing of fire severity may all modify the change trajectory of the fire-impacted permafrost ***,the observations and research on the relationships and interactive mechanisms among the forest fires,vegetation,carbon cycle and permafrost under a changing climate are still inadequate for a systematic impact *** the chronosequence approach of evaluating the temporal changes by measuring changes in the permafrost environment at different stages at various sites(possibly representing varied stages of permafrost degradation and modes),multi-source data assimilation and model predictions and simulations should be integrated with the results from long-and short-term field investigations,geophysical investigations and airborne surveys,laboratory testing and remote *** studies may enable quantitatively assess and predict the feed-back relationship and influence mechanism a

关键词： Forest fires Hydrothermal processes Organic layer thickness Active layer thickness Ecological thresholds Permafrost degradation Boreal and arctic regions

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Reactivation of hepatitis B virus infection – an important aspect of multifaceted problem

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World Journal of Gastroenterology 2024年第26期30卷 3193-3197页

作者： sergey Morozov sergey Batskikh Department of Gastroenterology Hepatology and NutritionFederal Research Center of NutritionBiotechnology and Food SafetyMoscow 115446Russia Department of Hepatology Moscow Clinical Scientific Center N.A.A.S.LoginovMoscow 111123Russia

In this editorial we comment on the article published in the recent issue of the W orld Journal of *** focus specifically on the problem of occult hepatitis B virus(HBV)infection,that is a result of previous hepatitis B(PHB)and a source for reactivation of *** prevalence of PHB is underestimated due to the lack of population testing ***,this condition not only com-plicate anticancer treatment,but may be responsible for the development of other diseases,like cancer or autoimmune *** we unveil possible mecha-nisms responsible for realization of these processes and suggest practical approa-ches for diagnosis and treatment.

关键词： Occult hepatitis B virus infection Hepatitis B virus reactivation Previous hepatitis B Cancer Autoimmune disorders

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structural stability of the Financial Market Model: Continuity of superhedging Price and Model Approximation

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Journal of the Operations Research society of China 2024年第1期12卷 215-241页

作者： sergey N.smirnov Faculty of Computational Mathematics and Cybernetics Lomonosov Moscow State UniversityMoscow119991Russian Federation

The present paper continues the topic of our recent paper in the same journal,aiming to show the role of structural stability in financial *** the context of financial market modeling,structural stability means that a specific“no-arbitrage”property is unaffected by small(with respect to the Pompeiu–Hausdorff metric)perturbations of the model’s *** formulate,based on our economic interpretation,a new requirement concerning“no arbitrage”properties,which we call the“uncertainty principle”.This principle in the case of no-trading constraints is equivalent to structural *** demonstrate that structural stability is essential for a correct model approximation(which is used in our numerical method for superhedging price computation).We also show that structural stability is important for the continuity of superhedging prices and discuss the sufficient conditions for this continuity.

关键词： Uncertainty structural stability No arbitrage Continuity of superhedging price Compact-valued multifunction Financial market model approximation Trading constraints

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spin-controlled generation of a complete polarization set with randomly-interleaved plasmonic metasurfaces

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Opto-Electronic Advances 2024年第8期7卷 16-24页

作者： sören im sande Yadong Deng sergey I.Bozhevolnyi Fei Ding Centre for Nano Optics University of Southern DenmarkOdense 5230Denmark

Optical metasurfaces,comprising subwavelength quasi-planar nanostructures,constitute a universal platform for manipulating the amplitude,phase,and polarization of light,thus paving a way for the next generation of highly integrated multifunctional optical *** this work,we introduce a reflective metasurface for the generation of a complete(angularly resolved)polarization set by randomly interleaving anisotropic plasmonic meta-atoms acting as nanoscale wave *** the proof-of-concept demonstration,we achieve multidirectional beam-steering into different polarization channels forming a complete set of polarization states,which can also be dynamically altered by switching the spin of incident *** developed design concept represents a significant advancement in achieving flat polarization optics with advanced functionalities.

关键词： plasmonic metasurface randomly interleaved multidirectional beam-steering spin-controlled all-polarization generation

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selection of shaped charges parameters for producing aluminum particles with velocities in the range of 2.5-16 km/s

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Defence Technology（防务技术） 2024年第8期38卷 126-135页

作者： Vladimir I.Kolpakov sergey V.Fedorov Ekaterina P.Vinogradova Irina A.Bolotina Bauman Moscow state Technical University Moscow 105005Russia

Testing rocket and space technology objects in ground conditions for resistance to the impact of meteoroids and fragments of space debris can be carried out using shaped charges. To substantiate the design parameters of shaped charges that ensure the formation of aluminum particles in a wide velocity range(from 2.5 to 16 km/s), numerical modeling of the formation process was carried out within the framework of a two-dimensional axisymmetric problem of continuum mechanics using three different computing codes to increase the reliability of the results. The calculations consider shaped charges with a diameter of 20-100 mm with aluminum liners of various shapes. It is shown that the formation of particles with velocities close to the lower limit of the considered range is ensured by gently sloping segmental liners of degressive thickness. To form higher-velocity particles with velocities over 5 km/s, it is proposed to use combined liners, the jet-forming part of which has the shape of a hemisphere of constant thickness or the shape of a semi-ellipsoid or semi-superellipsoid of rotation of degressive thickness.

关键词： space debris Meteoric impact Explosion shaped charge High-velocity aluminum element segmental liner Combined liner Numerical simulation

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Early selective enteral feeding in treatment of acute pancreatitis: A case report

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World Journal of Clinical Cases 2024年第3期12卷 637-642页

作者： Aleksei A Kashintsev sergey V Anisimov Anastasya Nadeeva Vitali Proutski sergey V Anisimov Anastasya NadeevaVitali ProutskiPANDICA LTDLondon WC1N 3ESUnited Kingdom

BACKGROUND Early initiation of enteral feeding is recognized to play a crucial role in improving the outcomes of treatment of acute ***,the method of adminis-tration of enteral nutrition remains *** present the experience of treating a patient with moderate-severe acute pancreatitis,at high risk of progressing to a severe or fatal condition,using a novel method of selective feeding with duodenal *** sUMMARY A 27-year-old female patient presented to the emergency unit of the hospital with a typical manifestation of acute *** a conventional treatment,the patient’s condition deteriorated by day 2 of *** an endoscopic approach,a novel catheter PandiCathffwas placed to the duodenum of the patient,isolating its segment between the duodenal bulb and the ligament of *** the isolated area created,a negative pressure was applied,followed by introduction of early selective enteral *** patient’s condition subsequently improved in a rapid manner,and no complications often associated with moderate-to-severe acute pancreatitis *** Within 48 h of starting treatment with the novel method,it can prevent the development of multiple organ failure and,when combined with minimally invasive drainage methods,help prevent infection.

关键词： Acute pancreatitis Enteral feeding Infectious complications systemic inflammatory response syndrome MODs

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