Water use efficiency(WUE),as a pivotal indicator of the coupling degree within the carbon–water cycle of ecosystems,holds considerable importance in assessment of the carbon–water balance within terrestrial ecosyste...Water use efficiency(WUE),as a pivotal indicator of the coupling degree within the carbon–water cycle of ecosystems,holds considerable importance in assessment of the carbon–water balance within terrestrial ecosystems.However,in the context of global warming,WUE evolution and its primary drivers on the Tibetan Plateau remain unclear.This study employed the ensemble empirical mode decomposition method and the random forest algorithm to decipher the nonlinear trends and drivers of WUE on the Tibetan Plateau in 2001–2020.Results indicated an annual mean WUE of 0.8088 gC/mm·m^(2)across the plateau,with a spatial gradient reflecting decrease from the southeast toward the northwest.Areas manifesting monotonous trends of increase or decrease in WUE accounted for 23.64%and 9.69%of the total,respectively.Remarkably,66.67%of the region exhibited trend reversals,i.e.,39.94%of the area of the Tibetan Plateau showed transition from a trend of increase to a trend of decrease,and 26.73%of the area demonstrated a shift from a trend of decrease to a trend of increase.Environmental factors accounted for 70.79%of the variability in WUE.The leaf area index and temperature served as the major driving forces of WUE variation.展开更多
The Qinghai-Tibet Plateau,with its high altitude and cold climate,is one of the most fragile ecological environments in China and is distinguished by its naturally elevated arsenic(As)levels in the soil,largely due to...The Qinghai-Tibet Plateau,with its high altitude and cold climate,is one of the most fragile ecological environments in China and is distinguished by its naturally elevated arsenic(As)levels in the soil,largely due to its rich mineral and geothermal resources.This review provides a comprehensive analysis of As content,focusing on its distribution,environmental migration,and transformation behavior across the plateau.The review further evaluates the distribution of As in different functional areas,revealing that geothermal fields(107.2 mg/kg),mining areas(53.8 mg/kg),and croplands(39.3 mg/kg)have the highest As concentrations,followed by river and lake sediments and adjacent areas(33.1 mg/kg).These elevated levels are primarily attributed to the presence of As-rich minerals,such as arsenopyrite and pyrite.Additionally,human activities,including mining and geothermal energy production,exacerbate the release of As into the environment.The review also highlights the role of localmicroorganisms,particularly those fromthe phyla Proteobacteria and Actinobacteria,which possess As metabolic genes that facilitate As translocation.Given the unique climatic conditions of the plateau,conventionalmethods for As controlmay not be fully effective.However,the review identifies promising remediation strategies that are environmentally adaptable,such as the use of local microorganisms,specific adsorbents,and integrated technologies,which offer potential solutions for managing and utilizing Ascontaminated soils on the plateau.展开更多
Rationally regulating the porosity of hard carbon(HC),especially the closed pores matching the low potential plateau and the ultra-microporous structure suitable for Na+embedding,has been shown to be the key to improv...Rationally regulating the porosity of hard carbon(HC),especially the closed pores matching the low potential plateau and the ultra-microporous structure suitable for Na+embedding,has been shown to be the key to improving the sodium storage performance and initial coulombic efficiency(ICE).However,the preparation of such HC materials with specific pore structures still faces great challenges.Herein,a simple pre-oxidation strategy is employed to construct abundant closed ultra-microporous structures in soy protein powder-derived HC material,achieving a significant improvement in its ICE and platform capacity.The pre-oxidation process promotes the cross-linking degree of the soy protein,thereby hindering the directional growth of graphite domains during the carbonization process.The optimized HC exhibits ultra-high platform capacity(329 mAh g^(-1))and considerable energy density(148.5 Wh kg^(-1)).Based on the ex-situ Raman and X-ray photoelectron spectroscopy characterization results,the excellent sodium storage capacity of the HC material is attributed to the synergistic effect of adsorption-intercalation/filling.The presented work provides novel insights into the synthesis of other biomass-derived HC materials with abundant closed ultra-micro pores.展开更多
In the context of global warming,it is anticipated that both the intensity and the frequency of future global extreme high precipitation(EHP)and extreme high temperature(EHT)events will increase.To evaluate the future...In the context of global warming,it is anticipated that both the intensity and the frequency of future global extreme high precipitation(EHP)and extreme high temperature(EHT)events will increase.To evaluate the future extreme climate changes in the Asian arid region and Tibetan Plateau,this study applied the NASA Earth Exchange Global Daily Downscaled Projections(NEX-GDDP-CMIP6)to assess the changes in EHP(Rx5d and R95pTOT)and EHT(TX90p and TXx)under different emission scenarios in the 21st century.Findings suggest that both the frequency and the intensity of the extreme indices will increase,exhibiting accelerated growth under higher emission scenarios,particularly under the SSP5-8.5 emission scenario.It is suggested that the growth of EHT and EHP in the early subperiod of the 21st century(2026-2045)will be relatively moderate,with small differences between different emission scenarios.However,by the middle subperiod of the 21st century(2041-2060),the differences between different emission scenarios will become larger than the 2035s and the growth will become more intense.In western central Asia,TX90p,TXx,Rx5d,and R95pTOT increase by 9.7%-14.2%(13.3%-24.7%),1.3℃-1.7℃(1.6℃-2.7℃),6.5%-8.9%(8.2%-8.8%),and 18.1%-27.0%(25.6%-30.0%)by the early(middle)subperiod;in eastern central Asia,TX90p,TXx,Rx5d,and R95pTOT increase 8.1%-12.0%(11.3%-21.1%),1.4℃-1.8℃(1.9℃-2.9℃),7.4%-9.7%(10.4%-13.8%),and 20.2%-29.3%(32.0%-40.8%)by the early(middle)subperiod;and over the Tibetan Plateau,TX90p,TXx,Rx5d,and R95pTOT increase 12.5%-17.4%(17.0%-31.0%),1.2℃-1.5℃(1.6℃-2.5℃),7.2%-10.0%(9.9%-15.0%),and 26.6%-33.1%(36.1%-55.3%)by the early(middle)subperiod.展开更多
On 19 May 2022, an outbreak of 105 red sprites that occurred over South Asia was fortuitously recorded by two amateurs from a site in the southern Tibetan Plateau(TP), marking the highest number captured over a single...On 19 May 2022, an outbreak of 105 red sprites that occurred over South Asia was fortuitously recorded by two amateurs from a site in the southern Tibetan Plateau(TP), marking the highest number captured over a single thunderstorm in South Asia. Nearly half of these events involved dancing sprites, with an additional 16 uncommon secondary jets and at least four extremely rare green emissions called “ghosts” observed following the associated sprites. Due to the absence of the precise timing needed to identify parent lightning, a method based on satellite motion trajectories and star fields is proposed to infer video frame timestamps within an error of less than one second. After verifying 95 sprites from two videos, our method identified the parent lightning for 66 sprites(~70%). The sprite-producing strokes, mainly of positive polarity with peak currents exceeding +50 k A, occurred in the stratiform region of a mesoscale convective complex(MCC)that spanned the Ganges Plain to the southern TP, with a cloud area over 200 000 km2 and a minimum cloud-top black body temperature near 180 K. This observation confirms that thunderstorms in South Asia, akin to mesoscale convective systems(MCSs) in the Great Plains of the United States or coastal thunderstorms in Europe, can produce numerous sprites,including complex species. Our analysis bears important implications for characterizing thunderstorms above the southern TP and examining their physical and chemical effects on the adjacent regions, as well as the nature of the coupling between the troposphere and middle-upper atmosphere in this region.展开更多
The Qinghai-Xizang Plateau of China faces challenges like thaw slumping,threatening slope stability and infrastructure.Understanding the mechanical properties of the roots of the dominant herbaceous plant species in t...The Qinghai-Xizang Plateau of China faces challenges like thaw slumping,threatening slope stability and infrastructure.Understanding the mechanical properties of the roots of the dominant herbaceous plant species in the alpine meadow layer of the permafrost regions on the Qinghai-Xizang Plateau is essential for evaluating their role in enhancing soil shear strength and mitigating slope deformation in these fragile environments.In this study,the roots of four dominant herbaceous plant species—Kobresia pygmaea,Kobresia humilis,Carex moorcroftii,and Leontopodium pusillum—that are widely distributed in the permafrost regions of the Qinghai-Xizang Plateau were explored to determine their mechanical properties and effects in enhancing soil shear strength.Through indoor single root tensile and root group tensile tests,we determined the root diameter,tensile force,tensile strength,tensile ratio,and strength frequency distributions.We also evaluated their contributions to inhibiting slope deformation and failure during the formation and development of thermal thaw slumps in the alpine meadow.The results showed that the distribution of the root diameter of the dominant plant species is mostly normal,while the tensile strength tends to be logarithmically normally distributed.The relationship between the root diameter and root tensile strength conforms to a power function.The theoretical tensile strength of the root group was calculated using the Wu-Waldron Model(WWM)and the Fiber Bundle Model(FBM)under the assumption that the cumulative single tensile strength of the root bundle is identical to the tensile strength of the root group in the WWM.The FBM considers three fracture modes:FBM-D(the tensile force on each single root is proportional to its diameter relative to the total sum of all the root diameters),FBM-S(the cross-sectional stress in the root bundle is uniform),and FBM-N(each tensile strength test of individual roots experiences an equal load).It was found that the model-calculated tensile strength of the root group was 162.60%higher than the test value.The model-derived tensile force of the root group from the FBM-D,FBM-S,and FBM-N was 73.10%,28.91%,and 13.47%higher than the test values,respectively.The additional cohesion of the soil provided by the roots was calculated to be 25.90-45.06 kPa using the modified WWM,67.05-38.15 kPa using the FBM-S,and 57.24-32.74 kPa using the FBM-N.These results not only provide a theoretical basis for further quantitative evaluation of the mechanical effects of the root systems of herbaceous plant species in reinforcing the surface soil but also have practical significance for the effective prevention and control of thermal thaw slumping disasters in the permafrost regions containing native alpine meadows on the Qinghai-Xizang Plateau using flexible plant protection measures.展开更多
Walking into the Institute of Plateau Biology(IPB in short)in Lhasa,Xizang,vice director Yang Le exchanged pleasantries with the guard in fluent Tibetan.Originally from Hunan Province,he has worked and lived here in X...Walking into the Institute of Plateau Biology(IPB in short)in Lhasa,Xizang,vice director Yang Le exchanged pleasantries with the guard in fluent Tibetan.Originally from Hunan Province,he has worked and lived here in Xizang for over 20 years."Now I see Xizang as my home,"he said with a smile.展开更多
Understanding how species diverge and adapt is fundamental to unraveling biodiversity.While environmental impacts on species evolution are well-documented,the roles of intrinsic life-history traits remain underexplore...Understanding how species diverge and adapt is fundamental to unraveling biodiversity.While environmental impacts on species evolution are well-documented,the roles of intrinsic life-history traits remain underexplored.The Qinghai-Xizang Plateau,with its harsh conditions and unique biodiversity,offers a natural laboratory for such investigations.Here,we examine two sympatric small mammals—the solitary,low-dispersal plateau zokor(Eospalax baileyi)and the social,high-dispersal plateau pika(Ochotona curzoniae)—to elucidate how life-history traits shape population structures and adaptive strategies.Through whole-genome sequencing and cardiac-blood phenotype analyses,we reveal striking differences in their evolutionary trajectories.Despite enduring similar environmental pressures,plateau zokor populations exhibit pronounced genetic subdivisions,high inbreeding,and distinct local adaptations.In contrast,plateau pika populations display genetic panmixia,widespread diversity,and adaptive uniformity.Demographic inference highlights that plateau zokors experienced severe population bottlenecks and restricted gene flow during glacial periods,underscoring the impact of dispersal capacity on evolutionary outcomes.Our findings demonstrate that intrinsic biological traits,particularly dispersal ability,fundamentally influence genetic architecture,population connectivity,and local adaptation.This study not only provides empirical evidence of how life-history traits shape evolutionary dynamics but also offers a framework for integrating intrinsic and extrinsic factors in understanding biodiversity formation.展开更多
Black tents,also known as black yak-wool tents due to their construction from yak wool,serve as the traditional accommodation for ethnic Tibetan nomads.From ancient times till now,these tents have long captured the no...Black tents,also known as black yak-wool tents due to their construction from yak wool,serve as the traditional accommodation for ethnic Tibetan nomads.From ancient times till now,these tents have long captured the nomadic life of herdsmen living on the Qinghai-Xizang Plateau.展开更多
The Tibetan Plateau(TP),known as the“Third Pole of Earth”,and its ecosystem is quite sensitive to climate change(Yao et al.,2012;Qiu,2008).In recent decades,the main TP has experienced warming and humidification(alt...The Tibetan Plateau(TP),known as the“Third Pole of Earth”,and its ecosystem is quite sensitive to climate change(Yao et al.,2012;Qiu,2008).In recent decades,the main TP has experienced warming and humidification(although there has been a drying trend in the southern region),and researchers anticipate that this change will continue in the future(Jiang et al.,2023;Sun et al.,2020;Chen et al.,2015).展开更多
At first glance,Lhapa Tsering appears modestly dressed,A:almost unassumingyet an artistic air surrounds him.A man of few words,his eyes light up with unmistakable passion the moment painting enters the conversation.Hi...At first glance,Lhapa Tsering appears modestly dressed,A:almost unassumingyet an artistic air surrounds him.A man of few words,his eyes light up with unmistakable passion the moment painting enters the conversation.His fingers lightly graze the paintbrush.展开更多
The Qinghai-Tibet Plateau possesses the thickest continental crust on Earth,yet the timing of its formation remains debated.In this study,we conducted zircon U-Pb isotopic dating,geochemical and Sr-Nd-Pb-Hf isotopic a...The Qinghai-Tibet Plateau possesses the thickest continental crust on Earth,yet the timing of its formation remains debated.In this study,we conducted zircon U-Pb isotopic dating,geochemical and Sr-Nd-Pb-Hf isotopic analyses on the Xuexiumaer biotite quartz monzonite porphyry(BQMP)sampled from the Lake Dajia area in southern Gangdese.This study aims to estimate the paleo-crustal thickness beneath this region during the early India-Asia collision stage using whole-rock Sr/Y and(La/Yb)N ratios as proxies.Results reveal that the Xuexiumaer BQMP was formed at~51 Ma in a collisional tectonic setting following Neo-Tethyan slab breakoff,and is an I-type granitoid derived primarily from partial melting of juvenile mafic lower crust with subordinate ancient crustal input.The estimated paleo-crustal thickness in the Lake Dajia area at~51 Ma is less than 40 km.This indicates that although the Qinghai-Tibet Plateau had already undergone significant crustal thickening and attained an exceptionally thick crust(>50 km)prior to the India-Asia collision as demonstrated by previous studies,some regions still maintained a crust only slightly thicker than the average continental crust(~35 km)at the initial collision stage.This limited crustal thickening likely resulted from underplating of subduction-related mafic magma at the mantle-crust boundary.展开更多
The Surface Water and Ocean Topography(SWOT)mission represents a collaborative effort between physical oceanography and hydrology fields,aimed at exchanging detailed topography information characterized by its high pr...The Surface Water and Ocean Topography(SWOT)mission represents a collaborative effort between physical oceanography and hydrology fields,aimed at exchanging detailed topography information characterized by its high precision in vertical measurements and extensive spatial detail.This data is generated by a scientific payload,with the Ka-band radar Interferometer(KaRin)serving as its primary tool.However,its smaller incidence angle increases layover regions,introducing noise during observations.Focused on four rugged high-altitude Xizang Plateau regions,this study evaluates the simulation of areas that are not affected by the Synthetic Aperture Radar(SAR)side-looking mode,using simulated SWOT orbit parameters and Digital Elevation Model(DEM)data derived from Shuttle Radar Topography Mission(SRTM).The results show that the imaging mode of KaRIn induces layover in terrain with significant variations,challenging precise topography retrieval.Utilizing the left and right swaths of swOT could enhance the observations along the east and west axis,suggesting multiple observations are necessary for the accuracy of surface terrain.The detection results of the lake mask show that KaRIn is adept at monitoring lakes,though their boundaries could be affected by adjacent riverbanks and nearby mountainous landscapes.The importance of mitigating layover impact cannot be overstated for heightened precision and expanded applications,thereby raising the significance of sWOT in environmental and scientific studies.展开更多
A subducted continental slab is sometimes torn during collision,yet the exact impact of slab-tearing on the overlying lithosphere remains unclear.Here,we image the structure and architecture of the Asian lithosphere a...A subducted continental slab is sometimes torn during collision,yet the exact impact of slab-tearing on the overlying lithosphere remains unclear.Here,we image the structure and architecture of the Asian lithosphere above the Indian slab in the eastern Tibetan Plateau using multiscale seismic tomography models and zircon Hf isotopic mapping,respectively.Our mantle V_(p)model shows that a large low-velocity anomaly extends laterally beneath the thinned Asian lithosphere above the tear zone roughly along the 26°N.The V_(s)images,magmatic records and Hf isotopic mapping indicate that this low-velocity anomaly recorded an asthenosphere flow eastward along the tear zone,which thermally eroded and refertilized the overlying Asian lithosphere,leading to the lithospheric melting,thinning and root delaminating.The vertical tear also generated a tectonic weak zone with associated Cenozoic potassic and carbonatitic magma suites.We argue that such a hot lithosphere discontinuity provided a reasonable mechanism for the abrupt change of crust thickness and the transformation of crust-mantle deformation from coupling to decoupling across the tear zone.展开更多
This paper focuses on the Qinghai-Xizang Plateau.It systematically reviews its seismic activity characteristics and extensive environmental effects under extreme climatic conditions in dry and cold seasons.Firstly,thr...This paper focuses on the Qinghai-Xizang Plateau.It systematically reviews its seismic activity characteristics and extensive environmental effects under extreme climatic conditions in dry and cold seasons.Firstly,through detailed data analysis and literature review,it is revealed how the seasonal significant rainfall and temperature changes in the plateau establish potential links with key parameters such as the frequency and intensity of seismic activity.This process deeply analyzes how natural conditions such as extreme rainfall and temperature changes directly or indirectly affect the mechanism of earthquake preparation and triggering,which may promote or inhibit the occurrence of seismic activity.The close relationship between cold and dry seasons and seismic activity is emphasized,and the unique influence of these special climatic conditions on seismic activity patterns is discussed.In addition,the regional distribution characteristics of seismic activity in the plateau area are also analyzed,including key data such as annual occurrence number and magnitude distribution,which provides strong data support for formulating regional earthquake disaster response strategies.In addition,the characteristics of various secondary disasters that may be caused by earthquakes,such as landslides,debris flows,barrier lakes,etc.,are analyzed,which deepens the understanding of the complexity of the earthquake disaster chain.The aim is to provide a scientific basis for future earthquake disaster prevention and control work and to promote the improvement of earthquake science research and disaster management levels in the Qingzang Plateau and even the world.展开更多
Various velocity models have been built for Southeast Qinghai-Xizang Plateau with the purpose of revealing the internal dynamics and estimating local seismic hazards.In this study,we use a 3-D full-waveform modeling p...Various velocity models have been built for Southeast Qinghai-Xizang Plateau with the purpose of revealing the internal dynamics and estimating local seismic hazards.In this study,we use a 3-D full-waveform modeling package to systematically validate three published continental-scale velocity models,that is,Shen2016,FWEA18,and USTClitho1.0,leveraging the ample datasets in Southeast Qinghai-Xizang Plateau region.Travel time residuals and waveform similarities are measured between observed empirical Green’s functions and synthetic waveforms.The results show that the Shen2016 model,derived from traditional surface wave tomography,performs best in fitting Rayleigh waves in the Southeast Qinghai-Xizang Plateau,followed by FWEA18,built from full-waveform inversion of long-period body and surface waves.The USTClitho1.0 model,although inverted from body wave datasets,is comparable with FWEA18 in fitting Rayleigh waves.The results also show that all the models are faster than the ground-truth model and show relatively large travel-time residuals and poor waveform similarities at shorter period bands,possibly caused by small-scale structural heterogeneities in the shallower crust.We further invert the time residuals for spatial velocity residuals and reveal that all three models underestimate the amplitudes of high-and low-velocity anomalies.The underestimated amplitude is up to 4%,which is non-negligible considering that the overall amplitude of anomalies is only 5%−10%in the crust.These results suggest that datasets and the inversion method are both essential to building accurate models and further refinements of these models are necessary.展开更多
The position of the South Asian High(SAH)over the Tibetan Plateau(TP)exhibits significant interannual variability.In this study,the criteria for defining the establishment and withdrawal of the SAH,as well as their ac...The position of the South Asian High(SAH)over the Tibetan Plateau(TP)exhibits significant interannual variability.In this study,the criteria for defining the establishment and withdrawal of the SAH,as well as their activities over the TP,are re-evaluated.The SAH is classified as“established over the TP”when the 1660 dagpm geopotential height contour covers 25%or more of the TP,and“withdrawn from the TP”when this contour covers less than 25%.Statistical analysis shows that,on average,the SAH establishes over the TP by the 4th pentad of May(28th pentad)and withdraws from the TP around the 2nd pentad of October(56th pentad).Over the past 50 years(1974–2023),the SAH has tended to establish over the TP earlier and withdraw later,resulting in a longer duration of control over the TP,with the rate of increase accelerating since 2017.The SAH exhibits a long-term linear trend of an eastward shift during both its establishment and withdrawal phases.The anomalous activity of the SAH over the TP is influenced by atmospheric heat sources.When there is anomalous warming(cooling)of atmospheric heating over the Bay of Bengal and the Indochina Peninsula,the SAH tends to establish and withdraw earlier and further westward(later and further eastward),with the westerly trough located over East Asia(the western part of the TP).展开更多
Understanding the local ecological security status and its underlying drivers can be used as an effective reference for balancing ecosystem development with societal needs. This study assesses the ecological security ...Understanding the local ecological security status and its underlying drivers can be used as an effective reference for balancing ecosystem development with societal needs. This study assesses the ecological security of the Loess Plateau(LP) by integrating ecosystem health and ecosystem services, explores the varying impacts of ecosystem structure, quality, and services on ecological security index(ESI), and identifies the key driving factors of ESI using the Geodetector model. The results show that:(1) the average ESI indicates a relatively safe ecological status in LP with a significant increase in ESI observed in 50.21% of the region, largely due to the ecological restoration programs.(2) Natural factors predominantly influence ESI, although human factors play a significant role in the earthy-rocky mountain region and plateau wind-sand region.(3) The interactions between driving factors have a much greater impact on ESI than any single factor, with the interactions between precipitation and human factors being the most influential combination. This study provides a novel perspective on assessing ecological security in LP. We recommend that future ecological restoration efforts should consider the varying roles of ecosystem structure, quality, and services in ESI while tailoring strategies to the primary driving factors based on local conditions.展开更多
Tibetan Plateau,as one of the most carbon intensive regions in China,is crucial in the carbon cycle,and accurately estimating its vegetation carbon density(C_(VEG))is essential for assessing regional and national carb...Tibetan Plateau,as one of the most carbon intensive regions in China,is crucial in the carbon cycle,and accurately estimating its vegetation carbon density(C_(VEG))is essential for assessing regional and national carbon balance.However,the spatial distribution of regional C_(VEG)is not available remains highly uncertain due to lack of systematic research,especially for different organs.Here,we investigated the spatial distribution patterns and driving factors of C_(VEG)among different plant organs(leaf,branch,trunk and root)by systematically field grid-sampling 2040 field-plots of plant communities over the Tibetan Plateau from 2019 to 2020.The results showed that the carbon content of plant organs ranged from 255.53 to 515.58 g kg^(-1),with the highest in branches and the lowest in roots.Among the different plant functional groups,the highest C_(VEG)was found in evergreen coniferous forests,and the lowest in desert grasslands,with an average C_(VEG)of 1603.98 g m^(-2).C_(VEG)increased spatially from northwest to southeast over the Tibetan Plateau,with MAP being the dominant factor.Furthermore,the total vegetation carbon stock on the Tibetan Plateau was estimated to be 1965.62 Tg for all vegetation types.Based on the comprehensive field survey dataset,the Random Forest model effectively predicted and mapped the spatial distribution of C_(VEG)(including aboveground,belowground,and the total biomass carbon density)over the Tibetan Plateau with notable accuracy(validation R2 values were 71%,56%,and 64%for C_(AGB),C_(BGB),and C_(VEG),respectively)at a spatial resolution of 1 km×1 km.Our findings can help improve the accuracy of regional carbon stock estimations and provide parameters for carbon cycle model optimization and remote sensing calibration in the future.展开更多
基金National Nonprofit Institute Research Grant of CAF,No.CAFYBB2018ZA004,No.CAFYBB2023ZA009Fengyun Application Pioneering Project,No.FY-APP-ZX-2023.02。
文摘Water use efficiency(WUE),as a pivotal indicator of the coupling degree within the carbon–water cycle of ecosystems,holds considerable importance in assessment of the carbon–water balance within terrestrial ecosystems.However,in the context of global warming,WUE evolution and its primary drivers on the Tibetan Plateau remain unclear.This study employed the ensemble empirical mode decomposition method and the random forest algorithm to decipher the nonlinear trends and drivers of WUE on the Tibetan Plateau in 2001–2020.Results indicated an annual mean WUE of 0.8088 gC/mm·m^(2)across the plateau,with a spatial gradient reflecting decrease from the southeast toward the northwest.Areas manifesting monotonous trends of increase or decrease in WUE accounted for 23.64%and 9.69%of the total,respectively.Remarkably,66.67%of the region exhibited trend reversals,i.e.,39.94%of the area of the Tibetan Plateau showed transition from a trend of increase to a trend of decrease,and 26.73%of the area demonstrated a shift from a trend of decrease to a trend of increase.Environmental factors accounted for 70.79%of the variability in WUE.The leaf area index and temperature served as the major driving forces of WUE variation.
基金supported by the Central Public-interest Scientific Institution Basal Research Fund(No.Y2024QC29)the Central Public-interest Scientific Institution Basal Research Fund(Nos.2024-jbkyywf-lwj and 2024-jbkyywf-zyj).
文摘The Qinghai-Tibet Plateau,with its high altitude and cold climate,is one of the most fragile ecological environments in China and is distinguished by its naturally elevated arsenic(As)levels in the soil,largely due to its rich mineral and geothermal resources.This review provides a comprehensive analysis of As content,focusing on its distribution,environmental migration,and transformation behavior across the plateau.The review further evaluates the distribution of As in different functional areas,revealing that geothermal fields(107.2 mg/kg),mining areas(53.8 mg/kg),and croplands(39.3 mg/kg)have the highest As concentrations,followed by river and lake sediments and adjacent areas(33.1 mg/kg).These elevated levels are primarily attributed to the presence of As-rich minerals,such as arsenopyrite and pyrite.Additionally,human activities,including mining and geothermal energy production,exacerbate the release of As into the environment.The review also highlights the role of localmicroorganisms,particularly those fromthe phyla Proteobacteria and Actinobacteria,which possess As metabolic genes that facilitate As translocation.Given the unique climatic conditions of the plateau,conventionalmethods for As controlmay not be fully effective.However,the review identifies promising remediation strategies that are environmentally adaptable,such as the use of local microorganisms,specific adsorbents,and integrated technologies,which offer potential solutions for managing and utilizing Ascontaminated soils on the plateau.
基金supported by the National Natural Science Foundation of China(42167068,22269020)the Gansu Province Higher Education Industry Support Plan Project(2023CYZC-68)the Central Guidance for Local Science and Technology Development Funds Project(YDZX20216200001007)。
文摘Rationally regulating the porosity of hard carbon(HC),especially the closed pores matching the low potential plateau and the ultra-microporous structure suitable for Na+embedding,has been shown to be the key to improving the sodium storage performance and initial coulombic efficiency(ICE).However,the preparation of such HC materials with specific pore structures still faces great challenges.Herein,a simple pre-oxidation strategy is employed to construct abundant closed ultra-microporous structures in soy protein powder-derived HC material,achieving a significant improvement in its ICE and platform capacity.The pre-oxidation process promotes the cross-linking degree of the soy protein,thereby hindering the directional growth of graphite domains during the carbonization process.The optimized HC exhibits ultra-high platform capacity(329 mAh g^(-1))and considerable energy density(148.5 Wh kg^(-1)).Based on the ex-situ Raman and X-ray photoelectron spectroscopy characterization results,the excellent sodium storage capacity of the HC material is attributed to the synergistic effect of adsorption-intercalation/filling.The presented work provides novel insights into the synthesis of other biomass-derived HC materials with abundant closed ultra-micro pores.
基金supported by the Second Tibetan Plateau Scientific Expedition and Research Program[grant number 2019QZKK0101]。
文摘In the context of global warming,it is anticipated that both the intensity and the frequency of future global extreme high precipitation(EHP)and extreme high temperature(EHT)events will increase.To evaluate the future extreme climate changes in the Asian arid region and Tibetan Plateau,this study applied the NASA Earth Exchange Global Daily Downscaled Projections(NEX-GDDP-CMIP6)to assess the changes in EHP(Rx5d and R95pTOT)and EHT(TX90p and TXx)under different emission scenarios in the 21st century.Findings suggest that both the frequency and the intensity of the extreme indices will increase,exhibiting accelerated growth under higher emission scenarios,particularly under the SSP5-8.5 emission scenario.It is suggested that the growth of EHT and EHP in the early subperiod of the 21st century(2026-2045)will be relatively moderate,with small differences between different emission scenarios.However,by the middle subperiod of the 21st century(2041-2060),the differences between different emission scenarios will become larger than the 2035s and the growth will become more intense.In western central Asia,TX90p,TXx,Rx5d,and R95pTOT increase by 9.7%-14.2%(13.3%-24.7%),1.3℃-1.7℃(1.6℃-2.7℃),6.5%-8.9%(8.2%-8.8%),and 18.1%-27.0%(25.6%-30.0%)by the early(middle)subperiod;in eastern central Asia,TX90p,TXx,Rx5d,and R95pTOT increase 8.1%-12.0%(11.3%-21.1%),1.4℃-1.8℃(1.9℃-2.9℃),7.4%-9.7%(10.4%-13.8%),and 20.2%-29.3%(32.0%-40.8%)by the early(middle)subperiod;and over the Tibetan Plateau,TX90p,TXx,Rx5d,and R95pTOT increase 12.5%-17.4%(17.0%-31.0%),1.2℃-1.5℃(1.6℃-2.5℃),7.2%-10.0%(9.9%-15.0%),and 26.6%-33.1%(36.1%-55.3%)by the early(middle)subperiod.
基金supported by the National Natural Science Foundation of China (Grant No.42394122)CAS Project of Stable Support for Youth Team in Basic Research Field (YSRR-018)+1 种基金the National Key R&D Program of China (2023YFC3007703)the Chinese Meridian Project, and the International Partnership Program of Chinese Academy of Sciences (183311KYSB20200003)。
文摘On 19 May 2022, an outbreak of 105 red sprites that occurred over South Asia was fortuitously recorded by two amateurs from a site in the southern Tibetan Plateau(TP), marking the highest number captured over a single thunderstorm in South Asia. Nearly half of these events involved dancing sprites, with an additional 16 uncommon secondary jets and at least four extremely rare green emissions called “ghosts” observed following the associated sprites. Due to the absence of the precise timing needed to identify parent lightning, a method based on satellite motion trajectories and star fields is proposed to infer video frame timestamps within an error of less than one second. After verifying 95 sprites from two videos, our method identified the parent lightning for 66 sprites(~70%). The sprite-producing strokes, mainly of positive polarity with peak currents exceeding +50 k A, occurred in the stratiform region of a mesoscale convective complex(MCC)that spanned the Ganges Plain to the southern TP, with a cloud area over 200 000 km2 and a minimum cloud-top black body temperature near 180 K. This observation confirms that thunderstorms in South Asia, akin to mesoscale convective systems(MCSs) in the Great Plains of the United States or coastal thunderstorms in Europe, can produce numerous sprites,including complex species. Our analysis bears important implications for characterizing thunderstorms above the southern TP and examining their physical and chemical effects on the adjacent regions, as well as the nature of the coupling between the troposphere and middle-upper atmosphere in this region.
基金supported by the Qinghai Science and Technology Department Project(2025-QY-225)the National Natural Science Foundation of China(42267024)the Second Comprehensive Scientific Investigation and Research Project of the Qinghai-Xizang Plateau(2019QZKK0905).
文摘The Qinghai-Xizang Plateau of China faces challenges like thaw slumping,threatening slope stability and infrastructure.Understanding the mechanical properties of the roots of the dominant herbaceous plant species in the alpine meadow layer of the permafrost regions on the Qinghai-Xizang Plateau is essential for evaluating their role in enhancing soil shear strength and mitigating slope deformation in these fragile environments.In this study,the roots of four dominant herbaceous plant species—Kobresia pygmaea,Kobresia humilis,Carex moorcroftii,and Leontopodium pusillum—that are widely distributed in the permafrost regions of the Qinghai-Xizang Plateau were explored to determine their mechanical properties and effects in enhancing soil shear strength.Through indoor single root tensile and root group tensile tests,we determined the root diameter,tensile force,tensile strength,tensile ratio,and strength frequency distributions.We also evaluated their contributions to inhibiting slope deformation and failure during the formation and development of thermal thaw slumps in the alpine meadow.The results showed that the distribution of the root diameter of the dominant plant species is mostly normal,while the tensile strength tends to be logarithmically normally distributed.The relationship between the root diameter and root tensile strength conforms to a power function.The theoretical tensile strength of the root group was calculated using the Wu-Waldron Model(WWM)and the Fiber Bundle Model(FBM)under the assumption that the cumulative single tensile strength of the root bundle is identical to the tensile strength of the root group in the WWM.The FBM considers three fracture modes:FBM-D(the tensile force on each single root is proportional to its diameter relative to the total sum of all the root diameters),FBM-S(the cross-sectional stress in the root bundle is uniform),and FBM-N(each tensile strength test of individual roots experiences an equal load).It was found that the model-calculated tensile strength of the root group was 162.60%higher than the test value.The model-derived tensile force of the root group from the FBM-D,FBM-S,and FBM-N was 73.10%,28.91%,and 13.47%higher than the test values,respectively.The additional cohesion of the soil provided by the roots was calculated to be 25.90-45.06 kPa using the modified WWM,67.05-38.15 kPa using the FBM-S,and 57.24-32.74 kPa using the FBM-N.These results not only provide a theoretical basis for further quantitative evaluation of the mechanical effects of the root systems of herbaceous plant species in reinforcing the surface soil but also have practical significance for the effective prevention and control of thermal thaw slumping disasters in the permafrost regions containing native alpine meadows on the Qinghai-Xizang Plateau using flexible plant protection measures.
文摘Walking into the Institute of Plateau Biology(IPB in short)in Lhasa,Xizang,vice director Yang Le exchanged pleasantries with the guard in fluent Tibetan.Originally from Hunan Province,he has worked and lived here in Xizang for over 20 years."Now I see Xizang as my home,"he said with a smile.
基金supported by the Second Tibetan Plateau Scientific Expedition and Research(STEP)Program(2019QZKK05010900 and 2019QZKK05010405)the National Natural Science Foundation of China(32100339 and 32200350)+3 种基金Yunnan Revitalization Talent Support Program Top team(202405AS350022)supported by the Youth Innovation Promotion Association,Chinese Academy of Sciencessupported by Yunnan Fundamental Research Projects(202201AU070208)supported by Yunnan Revitalization Talent Support Program Yunling Scholar Project(XML)。
文摘Understanding how species diverge and adapt is fundamental to unraveling biodiversity.While environmental impacts on species evolution are well-documented,the roles of intrinsic life-history traits remain underexplored.The Qinghai-Xizang Plateau,with its harsh conditions and unique biodiversity,offers a natural laboratory for such investigations.Here,we examine two sympatric small mammals—the solitary,low-dispersal plateau zokor(Eospalax baileyi)and the social,high-dispersal plateau pika(Ochotona curzoniae)—to elucidate how life-history traits shape population structures and adaptive strategies.Through whole-genome sequencing and cardiac-blood phenotype analyses,we reveal striking differences in their evolutionary trajectories.Despite enduring similar environmental pressures,plateau zokor populations exhibit pronounced genetic subdivisions,high inbreeding,and distinct local adaptations.In contrast,plateau pika populations display genetic panmixia,widespread diversity,and adaptive uniformity.Demographic inference highlights that plateau zokors experienced severe population bottlenecks and restricted gene flow during glacial periods,underscoring the impact of dispersal capacity on evolutionary outcomes.Our findings demonstrate that intrinsic biological traits,particularly dispersal ability,fundamentally influence genetic architecture,population connectivity,and local adaptation.This study not only provides empirical evidence of how life-history traits shape evolutionary dynamics but also offers a framework for integrating intrinsic and extrinsic factors in understanding biodiversity formation.
文摘Black tents,also known as black yak-wool tents due to their construction from yak wool,serve as the traditional accommodation for ethnic Tibetan nomads.From ancient times till now,these tents have long captured the nomadic life of herdsmen living on the Qinghai-Xizang Plateau.
基金supported by the Basic Science Center for Tibetan Plateau Earth System(No.41988101)the Science and Technology Plan Project of the Xizang Autonomous Region(No.XZ202201ZD0005G01)。
文摘The Tibetan Plateau(TP),known as the“Third Pole of Earth”,and its ecosystem is quite sensitive to climate change(Yao et al.,2012;Qiu,2008).In recent decades,the main TP has experienced warming and humidification(although there has been a drying trend in the southern region),and researchers anticipate that this change will continue in the future(Jiang et al.,2023;Sun et al.,2020;Chen et al.,2015).
文摘At first glance,Lhapa Tsering appears modestly dressed,A:almost unassumingyet an artistic air surrounds him.A man of few words,his eyes light up with unmistakable passion the moment painting enters the conversation.His fingers lightly graze the paintbrush.
基金financially supported by the National Natural Science Foundation of China(Grant Nos.92155305 and 42103066)the National Key Research and Development Plan(Grant No.2023YFC2908400 and 2024YFC2910102)the Fundamental Research Funds for the Central Universities(Grant No.FRF-TP-24-046A).
文摘The Qinghai-Tibet Plateau possesses the thickest continental crust on Earth,yet the timing of its formation remains debated.In this study,we conducted zircon U-Pb isotopic dating,geochemical and Sr-Nd-Pb-Hf isotopic analyses on the Xuexiumaer biotite quartz monzonite porphyry(BQMP)sampled from the Lake Dajia area in southern Gangdese.This study aims to estimate the paleo-crustal thickness beneath this region during the early India-Asia collision stage using whole-rock Sr/Y and(La/Yb)N ratios as proxies.Results reveal that the Xuexiumaer BQMP was formed at~51 Ma in a collisional tectonic setting following Neo-Tethyan slab breakoff,and is an I-type granitoid derived primarily from partial melting of juvenile mafic lower crust with subordinate ancient crustal input.The estimated paleo-crustal thickness in the Lake Dajia area at~51 Ma is less than 40 km.This indicates that although the Qinghai-Tibet Plateau had already undergone significant crustal thickening and attained an exceptionally thick crust(>50 km)prior to the India-Asia collision as demonstrated by previous studies,some regions still maintained a crust only slightly thicker than the average continental crust(~35 km)at the initial collision stage.This limited crustal thickening likely resulted from underplating of subduction-related mafic magma at the mantle-crust boundary.
基金supported by the National Natural Science Foundation of China(grant nos.42274028 and 41704023).
文摘The Surface Water and Ocean Topography(SWOT)mission represents a collaborative effort between physical oceanography and hydrology fields,aimed at exchanging detailed topography information characterized by its high precision in vertical measurements and extensive spatial detail.This data is generated by a scientific payload,with the Ka-band radar Interferometer(KaRin)serving as its primary tool.However,its smaller incidence angle increases layover regions,introducing noise during observations.Focused on four rugged high-altitude Xizang Plateau regions,this study evaluates the simulation of areas that are not affected by the Synthetic Aperture Radar(SAR)side-looking mode,using simulated SWOT orbit parameters and Digital Elevation Model(DEM)data derived from Shuttle Radar Topography Mission(SRTM).The results show that the imaging mode of KaRIn induces layover in terrain with significant variations,challenging precise topography retrieval.Utilizing the left and right swaths of swOT could enhance the observations along the east and west axis,suggesting multiple observations are necessary for the accuracy of surface terrain.The detection results of the lake mask show that KaRIn is adept at monitoring lakes,though their boundaries could be affected by adjacent riverbanks and nearby mountainous landscapes.The importance of mitigating layover impact cannot be overstated for heightened precision and expanded applications,thereby raising the significance of sWOT in environmental and scientific studies.
基金supported by the National Natural Science Foundation of China(92462304)National Key Technologies R&D Program(2022YFF0800903)。
文摘A subducted continental slab is sometimes torn during collision,yet the exact impact of slab-tearing on the overlying lithosphere remains unclear.Here,we image the structure and architecture of the Asian lithosphere above the Indian slab in the eastern Tibetan Plateau using multiscale seismic tomography models and zircon Hf isotopic mapping,respectively.Our mantle V_(p)model shows that a large low-velocity anomaly extends laterally beneath the thinned Asian lithosphere above the tear zone roughly along the 26°N.The V_(s)images,magmatic records and Hf isotopic mapping indicate that this low-velocity anomaly recorded an asthenosphere flow eastward along the tear zone,which thermally eroded and refertilized the overlying Asian lithosphere,leading to the lithospheric melting,thinning and root delaminating.The vertical tear also generated a tectonic weak zone with associated Cenozoic potassic and carbonatitic magma suites.We argue that such a hot lithosphere discontinuity provided a reasonable mechanism for the abrupt change of crust thickness and the transformation of crust-mantle deformation from coupling to decoupling across the tear zone.
基金supported by the National Natural Science Foundation of China (42461020)Gansu Province joint research fund project (24JRRA857,24JRRA847,24JRRA799).
文摘This paper focuses on the Qinghai-Xizang Plateau.It systematically reviews its seismic activity characteristics and extensive environmental effects under extreme climatic conditions in dry and cold seasons.Firstly,through detailed data analysis and literature review,it is revealed how the seasonal significant rainfall and temperature changes in the plateau establish potential links with key parameters such as the frequency and intensity of seismic activity.This process deeply analyzes how natural conditions such as extreme rainfall and temperature changes directly or indirectly affect the mechanism of earthquake preparation and triggering,which may promote or inhibit the occurrence of seismic activity.The close relationship between cold and dry seasons and seismic activity is emphasized,and the unique influence of these special climatic conditions on seismic activity patterns is discussed.In addition,the regional distribution characteristics of seismic activity in the plateau area are also analyzed,including key data such as annual occurrence number and magnitude distribution,which provides strong data support for formulating regional earthquake disaster response strategies.In addition,the characteristics of various secondary disasters that may be caused by earthquakes,such as landslides,debris flows,barrier lakes,etc.,are analyzed,which deepens the understanding of the complexity of the earthquake disaster chain.The aim is to provide a scientific basis for future earthquake disaster prevention and control work and to promote the improvement of earthquake science research and disaster management levels in the Qingzang Plateau and even the world.
基金supported by the Special Fund of the Institute of Geophysics,China Earthquake Administration(Nos.DQJB23R28 and DQJB22K40)the National Natural Science Foundation of China(Nos.42304078,U1839210 and 42104043).
文摘Various velocity models have been built for Southeast Qinghai-Xizang Plateau with the purpose of revealing the internal dynamics and estimating local seismic hazards.In this study,we use a 3-D full-waveform modeling package to systematically validate three published continental-scale velocity models,that is,Shen2016,FWEA18,and USTClitho1.0,leveraging the ample datasets in Southeast Qinghai-Xizang Plateau region.Travel time residuals and waveform similarities are measured between observed empirical Green’s functions and synthetic waveforms.The results show that the Shen2016 model,derived from traditional surface wave tomography,performs best in fitting Rayleigh waves in the Southeast Qinghai-Xizang Plateau,followed by FWEA18,built from full-waveform inversion of long-period body and surface waves.The USTClitho1.0 model,although inverted from body wave datasets,is comparable with FWEA18 in fitting Rayleigh waves.The results also show that all the models are faster than the ground-truth model and show relatively large travel-time residuals and poor waveform similarities at shorter period bands,possibly caused by small-scale structural heterogeneities in the shallower crust.We further invert the time residuals for spatial velocity residuals and reveal that all three models underestimate the amplitudes of high-and low-velocity anomalies.The underestimated amplitude is up to 4%,which is non-negligible considering that the overall amplitude of anomalies is only 5%−10%in the crust.These results suggest that datasets and the inversion method are both essential to building accurate models and further refinements of these models are necessary.
基金supported by the National Natural Science Foundation of China(Grant Nos.41930972 and 42475015)the Financial Meteorology Scientific and Technological Innovation Group of the China Meteorological Administration(Grant No.CMA2024ZD03).
文摘The position of the South Asian High(SAH)over the Tibetan Plateau(TP)exhibits significant interannual variability.In this study,the criteria for defining the establishment and withdrawal of the SAH,as well as their activities over the TP,are re-evaluated.The SAH is classified as“established over the TP”when the 1660 dagpm geopotential height contour covers 25%or more of the TP,and“withdrawn from the TP”when this contour covers less than 25%.Statistical analysis shows that,on average,the SAH establishes over the TP by the 4th pentad of May(28th pentad)and withdraws from the TP around the 2nd pentad of October(56th pentad).Over the past 50 years(1974–2023),the SAH has tended to establish over the TP earlier and withdraw later,resulting in a longer duration of control over the TP,with the rate of increase accelerating since 2017.The SAH exhibits a long-term linear trend of an eastward shift during both its establishment and withdrawal phases.The anomalous activity of the SAH over the TP is influenced by atmospheric heat sources.When there is anomalous warming(cooling)of atmospheric heating over the Bay of Bengal and the Indochina Peninsula,the SAH tends to establish and withdraw earlier and further westward(later and further eastward),with the westerly trough located over East Asia(the western part of the TP).
基金National Natural Science Foundation of China,No.42371103Natural Science Basic Research Plan in Shaanxi Province of China,No.2023-JC-YB-229。
文摘Understanding the local ecological security status and its underlying drivers can be used as an effective reference for balancing ecosystem development with societal needs. This study assesses the ecological security of the Loess Plateau(LP) by integrating ecosystem health and ecosystem services, explores the varying impacts of ecosystem structure, quality, and services on ecological security index(ESI), and identifies the key driving factors of ESI using the Geodetector model. The results show that:(1) the average ESI indicates a relatively safe ecological status in LP with a significant increase in ESI observed in 50.21% of the region, largely due to the ecological restoration programs.(2) Natural factors predominantly influence ESI, although human factors play a significant role in the earthy-rocky mountain region and plateau wind-sand region.(3) The interactions between driving factors have a much greater impact on ESI than any single factor, with the interactions between precipitation and human factors being the most influential combination. This study provides a novel perspective on assessing ecological security in LP. We recommend that future ecological restoration efforts should consider the varying roles of ecosystem structure, quality, and services in ESI while tailoring strategies to the primary driving factors based on local conditions.
基金supported by CAS Project for Young Scientists in Basic Research(YSBR-037)the National Natural Science Foundation of China(42141004,32430067)by the Second Tibetan Plateau Scientific Expedition and Research Program(STEP,2019QZKK060602).
文摘Tibetan Plateau,as one of the most carbon intensive regions in China,is crucial in the carbon cycle,and accurately estimating its vegetation carbon density(C_(VEG))is essential for assessing regional and national carbon balance.However,the spatial distribution of regional C_(VEG)is not available remains highly uncertain due to lack of systematic research,especially for different organs.Here,we investigated the spatial distribution patterns and driving factors of C_(VEG)among different plant organs(leaf,branch,trunk and root)by systematically field grid-sampling 2040 field-plots of plant communities over the Tibetan Plateau from 2019 to 2020.The results showed that the carbon content of plant organs ranged from 255.53 to 515.58 g kg^(-1),with the highest in branches and the lowest in roots.Among the different plant functional groups,the highest C_(VEG)was found in evergreen coniferous forests,and the lowest in desert grasslands,with an average C_(VEG)of 1603.98 g m^(-2).C_(VEG)increased spatially from northwest to southeast over the Tibetan Plateau,with MAP being the dominant factor.Furthermore,the total vegetation carbon stock on the Tibetan Plateau was estimated to be 1965.62 Tg for all vegetation types.Based on the comprehensive field survey dataset,the Random Forest model effectively predicted and mapped the spatial distribution of C_(VEG)(including aboveground,belowground,and the total biomass carbon density)over the Tibetan Plateau with notable accuracy(validation R2 values were 71%,56%,and 64%for C_(AGB),C_(BGB),and C_(VEG),respectively)at a spatial resolution of 1 km×1 km.Our findings can help improve the accuracy of regional carbon stock estimations and provide parameters for carbon cycle model optimization and remote sensing calibration in the future.
