The depositional environment of the sands of the cover formation is discussed. This study aims to determine the paleoenvironments of deposition of the sands of the cover formation in the Batéké Plateaus by s...The depositional environment of the sands of the cover formation is discussed. This study aims to determine the paleoenvironments of deposition of the sands of the cover formation in the Batéké Plateaus by studying sedimentary dynamics based on the description of lithological facies in the field and granulometric analyses in the laboratory. In the field, six (6) lithostratigraphic logs were surveyed and 42 sand samples were taken for laboratory analysis. In the laboratory, the samples underwent granulometric, sieving and sedimentometry analyses, after washing with running water using a 63 µm sieve. These analyses made it possible to determine the granulometric classes of the samples. The sieving results allowed to determine the granulometric parameters (mean, standard deviation, mode, median, skewness, flattening or kurtosis) using the method of moments with the software “Gradistat V.8”, granulometric parameters with which the granulometric facies, the mode of transport and the deposition environment were determined using the diagrams. Morphoscopy made it possible to determine the form and aspect of the surface of the quartz grains constituting these sands. Granulometric analyses show that these silty-clay or clayey-silty sands are fine sands and rarely medium sands, moderately to well sorted and rarely well sorted. The dominant granulometric facies is hyperbolic (sigmoid), with parabolic facies being rare. The primary mode of transport of these sands is saltation, which dominates rolling. The dispersion of points in the diagrams shows that these sands originate from two depositional environments: aeolian and fluvial. Morphoscopic analysis reveals the presence of clean rounded matt grains (RM), dirty rounded matt grains (RS), shiny blunt grains (EL) and shiny rounded grains (RL). The rounded matt grains exhibit several impact marks. The presence of dirty rounded grains with a ferruginous cement on their surface indicates that these sands have been reworked. These sands have undergone two types of transport, first by wind (aeolian environment) and then by water (fluvial environment).展开更多
Variation in the location of the South Asian High （SAH） in early boreal summer is strongly influenced by elevated surface heating from the Tibetan Plateau （TP） and the Iranian Plateau （IP）. Based on observationa...Variation in the location of the South Asian High （SAH） in early boreal summer is strongly influenced by elevated surface heating from the Tibetan Plateau （TP） and the Iranian Plateau （IP）. Based on observational and ERA-Interim data, diagnostic analyses reveal that the interannual northwestward-southeastwaxd （NW-SE） shift of the SAH in June is more closely correlated with the synergistic effect of concurrent surface thermal anomalies over the TP and IP than with each single surface thermal anomaly over either plateau from the preceding May. Concurrent surface thermal anomalies over these two plateaus in May are characterized by a negative correlation between sensible heat flux over most parts of the TP （TPSH） and IP （IPSH）. This anomaly pattern can persist till June and influences the NW-SE shift of the SAH in June through the release of latent heat （LH） over northeastern India. When the IPSH is stronger （weaker） and the TPSH is weaker （stronger） than normal in May, an anomalous cyclone （anticyclone） appears over northern India at 850 hPa, which is accompanied by the ascent （descent） of air and anomalous convergence （divergence） of moisture flux in May and June. Therefore, the LH release over northeastern India is strengthened （weakened） and the vertical gradient of apparent heat source is decreased （increased） in the upper troposphere, which is responsible for the northwestward （southeastward） shift of the SAH in June.展开更多
Oceanic plateaus are large igneous provinces in the oceans,created by massive underwater eruptions,but their late-stage volcanism is poorly understood.With the addition of recent high-quality bathymetric data to exist...Oceanic plateaus are large igneous provinces in the oceans,created by massive underwater eruptions,but their late-stage volcanism is poorly understood.With the addition of recent high-quality bathymetric data to existing data,286 secondary cones were discovered over Shatsky Rise oceanic plateau.These cones with steeper flank slopes(mean 6.1°±4.4°)and smaller sizes(102–1923 m in height)are morphologically distinct from the plateau,and they are thought to have formed after the main volcanic episodes.Cone height and characteristic height(420 m)are close to seamounts in the Pacific Ocean,whereas greater than those in the Atlantic Ocean.Mean flatness of Shatsky Rise’s cones(0.25±0.20)are similar to that of seamounts in both Pacific and Atlantic Oceans,but notably density in cone distribution(0.56 km^-3)and their mean slope are significantly lower than those of seamounts in the two oceans.Lower slopes of secondary cones within Shatsky Rise may be explained by higher effusion rates of remaining magma.Although cone formation was expected to have a link to rifting by seafloor spreading,weak relationship between cone orientation and magnetic anomaly pattern implies that the expectation is negative.Moreover,weak correlation between the cone height and depth indicates it is not true that volcanic cones grow taller when they occur closer to the massif summits with thicker oceanic crust,which was suggested as the increase in hydraulic pressure.Cone height and flatness are also not strongly related,implying that remaining magma supply was too limited to foster the cones to critical height.展开更多
Taking Niyang River Basin as an example, applying with the indices of landscape pattern, the indices of ecological risk of ecosystems are calculated in this paper, which takes the value of ecological loss of main ecos...Taking Niyang River Basin as an example, applying with the indices of landscape pattern, the indices of ecological risk of ecosystems are calculated in this paper, which takes the value of ecological loss of main ecosystem as the evaluation standard and takes into account the impacts of probability or the velocity of main hazards and event of the ecosystem. And the grades of ecological risk are assessed. According to the results of assessment, the ecological risk grades of the basin are divided into five classes. From the first grade risk to the fifth grade risk, the values of regional risk indices gradually reduce. The first grade risk areas mainly distribute in Niyang river and its branches downstream and the surrounding areas of main towns. And the basin area of non-valley region and the headstream regions of the branches are the fifth grades risk areas. This evaluation results provide the basis to the regional sustainable development.展开更多
As one of the main non-zonal factors,the mass elevation effect(MEE)has significant impacts on both regional climates and mountain ecological patterns.In recent years,with the development of quantitative techniques and...As one of the main non-zonal factors,the mass elevation effect(MEE)has significant impacts on both regional climates and mountain ecological patterns.In recent years,with the development of quantitative techniques and methods,quantitative studies on the MEE and its implication on mountain altitudinal belts have developed rapidly.However,some issues have not been solved yet,such as high errors in spatial temperature estimations and difficulties in the definition and extraction of intramountain base elevation.Moreover,there is still a lack of comparative studies on the MEE and its influence on treelines and snowlines as most studies were conducted on specific mountains or plateaus.To compare the MEE magnitudes of the Tibetan Plateau(TP)and the Bolivian Plateau(BP),we estimated the correspondent air temperatures and simulated the solar radiations based on MODIS surface temperature,station observation,and treeline data.Then,we analyzed the elevation of the 10℃isotherms on the two plateaus,the temperatures at the same elevation,and the solar radiations.According to the mechanism of the MEE and the relationship of solar radiation and treeline,we constructed treeline models for the two plateaus through a stepwise regression analysis by considering several influencing factors of the MEE(e.g.,air temperature and precipitation)and using solar radiation as its proxy.The results showed that:(1)the MEE magnitude on the TP is equivalent to that on the BP although the former is slightly higher than the latter;(2)the MEE strongly influences the highest treelines in the northern and southern hemispheres,which both occur on the two plateaus.Notably,the treeline distribution models based on solar radiation had higher accuracies than those models with parameters of temperature and precipitation(the adjusted R^(2)values were 0.76 for the TP and 0.936 for the BP),indicating that solar radiation can be used to quantify the MEE and its implications on treelines.Overall,the results of this study can serve as a basis for subsequent analyses on the MEE’s impact factors.展开更多
Cryogenic wedges developed due to very cold,rather arid conditions during the maximum of the last cold event when the drying up of the neighboring China Sea resulted in the failure of the East Asian Monsoon.As the cli...Cryogenic wedges developed due to very cold,rather arid conditions during the maximum of the last cold event when the drying up of the neighboring China Sea resulted in the failure of the East Asian Monsoon.As the climate ameliorated and the Monsoon rains reappeared,ice-wedges developed.Further warming permitted thawing of the ice infillings accompanied by replacement of the ice by sediments partly from the host ground as well as from the surface by wind or sheet wash.In cases of extreme surface water flow on slopes after 10 ka B.P.,small baydjarakhs typically c.50 cm high developed,only to have the resulting hollows infilled by sediments carried by wind and/or sheet wash.These shallow structures form a network on top of many of the cryogenic wedges.This complex history makes dating the ages of the wedges difficult using OSL methodology.Unfortunately,past field work ignored the problem of the angle of the cut face to the direction of the wedge infilling when sampling the contents of the narrow wedges,resulting in potential contamination of the samples with the host sediment.Sampling of the larger deposits should be alright,but the likelihood of contamination makes the interpretation of the resulting OSL dates from the narrow wedges questionable.Primary wedges consisting of primary mineral infillings should still have similar OSL dates with depth for a given wedge,but the distinction between ice-wedge infillings and soil wedges is difficult since both can exhibit older dates of the infillings with depth.The available data suggests that ice-wedges were significantly more common than sediment-filled primary wedges.A protocol to avoid having to obtain large numbers of OSL dates by more careful field sampling and the use of grain size determinations is provided in the Appendix.展开更多
In southern Asia,there are three large-scale wave-like mountains ranging from the Tibetan Plateau westward to the Iranian Plateau and the Armenian Plateau.On the southern side between plateaus,there are the Indian Pen...In southern Asia,there are three large-scale wave-like mountains ranging from the Tibetan Plateau westward to the Iranian Plateau and the Armenian Plateau.On the southern side between plateaus,there are the Indian Peninsula and the Arabian Peninsula.What dynamic mechanisms form the directional alignment of the three plateaus with the two peninsulas remains a mystery.In the early stages of the Earth’s geological evolution,the internal structure of the Earth was that the center was a solid core,and the outmost layer was a thin equatorial crust zone separated by two thick pristine continents in polar areas,while the middle part was a deep magma fluid layer.Within the magma fluid layer,thermal and dynamic differences triggered planetary-scale vertical magma cells and led to the core-magma angular momentum exchange.When the core loses angular momentum and the magma layer gains angular momentum,the movement of upper magma fluids to the east and the tropical convergence zone(TCZ)drives the split and drift of two thick pristine continents,eventually forming the current combination of these plateaus and peninsulas and their wave-like arrangement along the east-west direction.Among them,the horizontal orthogonal convergence(collision)of upper magma fluids from the two hemispheres excited the vertical shear stress along the magma TCZ,which is the dynamic mechanism of mountain uplifts on the north side and plate subductions on the south side.To confirm this mechanism,two examples of low-level winds are used to calculate the correspondence between cyclone/anticyclonic systems generated by the orthogonal collision of airflows along the atmospheric TCZ and satellite-observed cloud systems.Such comparison can help us revisit the geological history of continental drift and orogeny.展开更多
This study investigates the relationship between the hotspot-ridge interaction and the formation of oceanic plateaus and seamounts in the Southwest Indian Ocean.We first calculated the relative distance between the So...This study investigates the relationship between the hotspot-ridge interaction and the formation of oceanic plateaus and seamounts in the Southwest Indian Ocean.We first calculated the relative distance between the Southwest Indian Ridge(SWIR)and relevant hotspots on the basis of models of plate reconstruction,and then calculated the corresponding excess magmatic anomalies of the hotspots on the basis of residual bathymetry and Airy isostasy.The results reveal that the activities of the Marion hotspot can be divided into three main phases:interaction with the paleo-Rodrigues triple junction(73.6-68.5 Ma),interaction with the SWIR(68.5-42.7 Ma),and intra-plate volcanism(42.7-0 Ma).These three phases correspond to the formation of the eastern,central,and western parts of the Del Cano Rise,respectively.The magnitude and apparent periodicity of the magmatic volume flux of the Marion hotspot appear to be dominated by the hotspot-ridge distance.The periodicity of the Marion hotspot is about 25 Ma,which is much longer than that of the Hawaii and Iceland hotspots(about 15 Ma).展开更多
The Series Barbini(subfamily Cyprininae sensu lato)is the most species-rich group within the family Cyprinidae,primarily confined to warm regions of southern Eurasia and Africa.The distribution patterns and evolutiona...The Series Barbini(subfamily Cyprininae sensu lato)is the most species-rich group within the family Cyprinidae,primarily confined to warm regions of southern Eurasia and Africa.The distribution patterns and evolutionary history of Chinese cyprinins have been effectively shaped by the Cenozoic uplift of the Qinghai-Tibet Plateau and the evolution of the Asian monsoon.Here,we describe two new fossil fishes from the early and middle Miocene of the Lunpola Basin in central Qinghai-Tibet Plateau,China,preserving the ethmoid and the rear of the occipital regions of the neurocranium,infraorbitals,hyopalatine arch,abdominal vertebrae,and some dorsal-fin pterygiophores and unbranched fin rays.Through detailed morphological comparisons,these fossils show definite affinities to Cyprinidae according to the morphology of the neurocranium,vertebral column,and dorsal fin rays;and one of which is classified into the Series Barbini,while the other can only be assigned to the Cyprinidae family level.These findings reveal that the hinterland of the plateau of the early Neogene should have hosted cyprinin fishes of greater diversity than today.This also indicates a warm-temperate paleoclimate suitable for their survival during that period,consistent with the paleoenvironmental and paleoclimatical conditions reconstructed from the contemporaneous mammalian fossil and palynological evidences.展开更多
Accurate water budget closure is critical for sustainable water resource management facing increased pressures from climate change and human activities.Although error reduction methods for individual water balance com...Accurate water budget closure is critical for sustainable water resource management facing increased pressures from climate change and human activities.Although error reduction methods for individual water balance components have advanced,persistent biases remain due to the independent development of datasets,impacting basin scale water budget balance.In this research,we analyzed the mathematical origin of the bias between water budget components and developed a new basin-scale water balance calibration method that redistributes errors across components while enforcing water balance constraints.Validation confirms systematic improvements,with reduced RMSE(Precipitation:-2.29 mm/month;ET:-1.34 mm/month)and increased R2 against in situ observations.Applied to the Jinghe River Basin(2000−2019),the calibrated data reveal declining precipitation(-1.70 mm/year)and evapotranspiration(-1.84 mm/year)alongside slightly increasing runoff(0.20 mm/year in basin depth),signaling a drying trend.Land cover changes—marked by cropland loss(-3,497 km^(2))and forest(+720 km^(2))and grassland(+2,776 km^(2))expansion—reflect improved water consumption requirements by ecosystem,raising concerns for water retention and ecosystem stability.The method is particularly effective for ungauged basins with sparse ground data and underscores the need for integrated land-water management to enhance long-term resilience.展开更多
Insight into the carbon turnover in soil aggregates and density fractions is essential for reducing the uncertainty in estimating carbon pools on the Tibetan Plateau,and how they vary with land use type is unclear.In ...Insight into the carbon turnover in soil aggregates and density fractions is essential for reducing the uncertainty in estimating carbon pools on the Tibetan Plateau,and how they vary with land use type is unclear.In this study,the effect of land use type on carbon storage and fractionation was quantified based on organic carbon and its ^(13)C abundance at the microscale of soil aggregates and density fractions in Tibetan alpine ecosystems.The sequence of soil aggregate destruction in the land use types of plantation(13.1%)<shrubland(32.7%)<grassland(47.9%)<farmland(61.8%)shows that plantations strengthen the soil structure.Plantation land had a greater contribution of light fraction organic carbon(28.3%)but a lower contribution of mineral-associated organic carbon(40.6%)to the carbon stock compared to farmland(13.5 and 70.3%).Interestingly,plantation land enhanced the aggregational differentiation of organic carbon and ^(13)C in each density fraction,whereas no such phenomenon existed in the soil organic carbon.Carbon isotope analyses revealed that carbon transfer in the plantation land occurred from the light fraction in macroaggregates(–24.9‰)to the mineral-associated fraction in microaggregates(–19.9‰).When compared to the other three land use types,the low transferability of carbon in aggregates and density fractions in plantation land provides a stable carbon pool for the Tibetan Plateau.This study shows that plantations can mitigate global climate change by slowing carbon transfer and increasing carbon storage at the microscale of aggregates and density fractions in alpine regions.展开更多
Glacial lake outburst floods(GLOFs)are increasingly frequent under warming and degradation,exerting profound impacts on regional ecosystems,geomorphology,and human systems.Ice-dammed lakes account for nearly 70% of GL...Glacial lake outburst floods(GLOFs)are increasingly frequent under warming and degradation,exerting profound impacts on regional ecosystems,geomorphology,and human systems.Ice-dammed lakes account for nearly 70% of GLOFs worldwide,yet their dynamics remain poorly understood in remote regions such as the interior Tibetan Plateau.Here,we present the first systematic assessment of the evolution and drainage of ice-dammed lakes across the region using multi-source satellite imagery.Between 1973 and 2024,the number of ice-dammed lakes increased from 256 to 323,while the total area declined from 22.66±0.93 km^(2) to 20.43±1.6 km^(2) due to repeated drainage and diminished reservoir capacity.Newly formed lakes tended to shift toward higher elevations.A total of 775 previously unreported GLOFs were detected based on abrupt lake area loss.Bayesian regression reveals a sharp rise in GLOF frequency,from an average of 11 GLOFs per year during 1990-1994 to 42.6 GLOFs per year during 2020-2024.Meanwhile,GLOF timing has shifted earlier by 9.07±3.71 days,and pre-drainage lake areas declined by 0.02±0.01 km^(2) compared to 1990.These findings highlight the evolving behavior of ice-dammed lakes in response to climate change and glacial recession,with important implications for regional cryospheric research and disaster mitigation.展开更多
The Kumkol Basin,situated in the northern margin of the Qinghai-Xizang Plateau,provides a unique window into understanding the dynamic mechanisms driving the plateau’s northern expansion.However,its formation and tec...The Kumkol Basin,situated in the northern margin of the Qinghai-Xizang Plateau,provides a unique window into understanding the dynamic mechanisms driving the plateau’s northern expansion.However,its formation and tectonic evolution remain poorly understood due to limited geophysical data in this region.In this study,we computed cross-correlations for the TT components of station-pairs with high signal-to-noise ratios to extract Love wave waveforms and further performed Lovewave ambient noise tomography to image the upper crustal shear-wave velocity structure of the Kumkol basin down to 10 km depth.Our seismic velocity model reveals that the Kumkol Basin has a sedimentary thickness exceeding 8 km,with its center located near the Arka Mountain on the southern side.This suggests that the basin was likely formed as a foreland basin in response to the uplift of the Qiman Tagh Mountain to the north.Additionally,integrated with seismic reflection data,our seismic velocity model images a detachment fault at the basin basement depth.We inferred that the Kumkol Anticlinorium at the basin’s center have been produced by multiple thrust faults converging into this detachment fault at 8–10 km depth following the Early to Middle Miocene uplift of the Qiman Tagh Mountain.This structural configuration indicates pulsed basinward deformation since the late Miocene,likely reflecting a tectonic regime shift from extrusion to distributed shortening in the northern Qinghai-Xizang Plateau.Our findings provide a high-resolution velocity model of the Kumkol Basin,offering critical insights into its structural evolution and supporting future resource exploration in this underexplored region.展开更多
The National Geophysical Data Center(NGDC)of the United States has collected aeromagnetic data for input into a series of geomagnetic models to improve model resolution;however,in the Tibetan Plateau region,ground-bas...The National Geophysical Data Center(NGDC)of the United States has collected aeromagnetic data for input into a series of geomagnetic models to improve model resolution;however,in the Tibetan Plateau region,ground-based observations remain insufficient to clearly reflect the characteristics of the region’s lithospheric magnetism.In this study,we evaluate the lithospheric magnetism of the Tibetan Plateau by using a 3D surface spline model based on observations from>200 newly constructed repeat stations(portable stations)to determine the spatial distribution of plateau geomagnetism,as well as its correlation with the tectonic features of the region.We analyze the relationships between M≥5 earthquakes and lithospheric magnetic field variations on the Tibetan Plateau and identify regions susceptible to strong earthquakes.We compare the geomagnetic results with those from an enhanced magnetic model(EMM2015)developed by the NGDC and provide insights into improving lithospheric magnetic field calculations in the Tibetan Plateau region.Further research reveals that these magnetic anomalies exhibit distinct differences from the magnetic-seismic correlation mechanisms observed in other tectonic settings;here,they are governed primarily by the combined effects of compressional magnetism,thermal magnetism,and deep thermal stress.This study provides new evidence of geomagnetic anomalies on the Tibetan Plateau,interprets them physically,and demonstrates their potential for identifying seismic hazard zones on the Plateau.展开更多
While the Ordos Basin is recognized for its substantial hydrocarbon exploration prospects,its rugged loess tableland terrain has rendered seismic exploration exceptionally challenging[1-3].Persistent obstacles such as...While the Ordos Basin is recognized for its substantial hydrocarbon exploration prospects,its rugged loess tableland terrain has rendered seismic exploration exceptionally challenging[1-3].Persistent obstacles such as complex 3D survey planning,low signal-tonoise ratio raw data,inadequate near-surface velocity modeling,and imaging inaccuracy have long hindered the advancement of seismic exploration across this region.Through a problem-solving approach rooted in geological target analysis,this research systematically investigates the behavioral patterns of nodal seismometer-based high-density seismic acquisition in loess plateau.Tailored advancements in waveform enhancement and depth velocity modelling methodologies have been engineered.Field validations confirm that the optimized workflow demonstrates marked improvements in amplitude preservation and imaging resolution,offering novel insights for future reservoir characterization endeavors.展开更多
This study examines a 1.32 m thick sediment sequence from the Cunge sag pond in the Litang Basin,eastern Tibetan Plateau,to assess the seismicity of the Litang fault during the Holocene.High-resolution geochemical,gra...This study examines a 1.32 m thick sediment sequence from the Cunge sag pond in the Litang Basin,eastern Tibetan Plateau,to assess the seismicity of the Litang fault during the Holocene.High-resolution geochemical,grain size,magnetic susceptibility,and total organic carbon indicators are employed to obtain a continuous record of changes in elemental,physical,and biological properties within the profile to identify seismic events.The seismic event layer generally comprises two sedimentary rhythms:a lower coarse sand layer and an upper fine silt-clay layer.These layers represent rapid deposition associated with fault activity(Earthquake A)and slower deposition during calm periods or earthquake recurrence intervals(Seismic interval A).Through six^(14)C dating,five seismic events have been identified in the Cunge sag pond section:E1(before 3955 a B.P.),E2(3713-3703 a B.P.),E3(3492-3392 a B.P.),E4(2031-1894 a B.P.),and E5(1384-1321 a B.P.).E1-E4 had shown a good consistency with the paleo-earthquake recorded by the trench,and whereas E5 is a newly identified seismic event,further improving the continuous earthquake sequence of the Litang fault.Based on existing trench data and the seismic event record from the Cunge sag pond,a total of 11 paleo-earthquakes are identified along the Litang fault since the Holocene.The paleo-earthquake activity of the Litang fault exhibits a clustered pattern,with recurrence intervals of both long periods(1000 a)and short periods(500 a).Since 5000 a,the interval between strong earthquake recurrences gradually decreases,indicating an increasing risk of strong earthquakes along the Litang fault.This study presents a continuous record of paleo-earthquakes along the Litang fault,eastern Tibetan Plateau,and can enhance the understanding of regional seismic activity.展开更多
Located on the Qinghai-Xizang Plateau,the Xizang Autonomous Region boasts exceptional solar energy resources.Today,sunlight is being converted into electricity by a 100 megawatt(MW)photovoltaic power station in Chabal...Located on the Qinghai-Xizang Plateau,the Xizang Autonomous Region boasts exceptional solar energy resources.Today,sunlight is being converted into electricity by a 100 megawatt(MW)photovoltaic power station in Chabala Township,Quxu County,Lhasa.Built by Huadian(Quxu)New Energy Co.,Ltd,the project is at an average altitude of 4,000 meters above sea level.It has become a powerful driver of green development in the region,ushering in a new chapter of harmonious coexistence between humanity and nature.展开更多
Global climate change is a pressing environmental challenge.Climate-induced migration highlights the severe impact of unsuitable climatic conditions.However,current research methods are limited in their ability to ass...Global climate change is a pressing environmental challenge.Climate-induced migration highlights the severe impact of unsuitable climatic conditions.However,current research methods are limited in their ability to assess climate suitability for residents in high-altitude areas.In this study,we assess climate suitability across the Qinghai-Xizang Plateau from 1979 to 2018 and project future changes using four different Shared Socioeconomic Pathway(SSP)climate scenarios by constructing the Climate Suitability Index(CSI).The findings reveal a notable increase in CSI from 0.32 to 0.36 from 1979 to 2018.The primary factors contributing to the increased climate suitability are increasing annual mean precipitation(61.42%)and decreasing solar radiation(17.22%)from 1979 to 2018.Furthermore,the study forecasts a continued enhancement of climate suitability across all SSP scenarios,with SSP585 demonstrating the greatest improvement,followed by SSP370,SSP245,and SSP126.Although low oxygen levels at high altitudes remain a challenge,the overall improvement in climate suitability offers hope for people living at high altitudes to cope with climate change.展开更多
Prolonged droughts have emerged as a major impediment to the revitalization of pastoral regions worldwide because they significantly augment their susceptibility to the deleterious effects of global climate change,ove...Prolonged droughts have emerged as a major impediment to the revitalization of pastoral regions worldwide because they significantly augment their susceptibility to the deleterious effects of global climate change,overgrazing,and land degradation.This study,conducted in 106 pastoral villages across 33 pastoral banners of Inner Mongolia Autonomous Region of China between August 2021 and October 2022,used a community resilience evaluation indicator system to assess drought resistance.By calculating a community resilience index,the research explored influencing factors and proposed countermeasures,aiming to enhance resilience to prolonged drought.The results revealed three key findings.1)Pastoral areas exhibited a limited degree of community resilience to drought disasters(overall score=0.28),with resilience levels forming a pyramid-shaped hierarchy.2)Dimensional analysis showed that resilience scores decreased sequentially across five domains:social(0.53)>cultural(0.44)>environmental(0.38)>economic(0.32)>management(0.27).These results highlight the crucial role of economic and management resilience in enhancing community resilience,particularly when accompanied by pre-and post-disaster government support and social security,both of which must be improved.3)Key factors influencing community resilience included geographical location,traffic accessibility,and frequency and severity of droughts.From a drought resilience perspective,targeted strategies and recommendations are proposed to provide novel and practical approaches for achieving sustainable development in pastoral areas and rural regions as a whole.展开更多
Ecosystems along the eastern margin of the Qinghai-Tibet Plateau(EQTP)are highly fragile and extremely sensitive to climate change and human disturbances.To quantitatively assess climate-induced ecosystem responses,th...Ecosystems along the eastern margin of the Qinghai-Tibet Plateau(EQTP)are highly fragile and extremely sensitive to climate change and human disturbances.To quantitatively assess climate-induced ecosystem responses,this study proposes a Climate-Induced Productivity Index(CIPI)based on the Super Slack-Based Measure(Super-SBM)model using remote sensing data from 2001 to 2020.The results reveal persistently low CIPI values(0.47-0.53)across major ecosystem types,indicating widespread vulnerability to climatic variability.Among these ecosystems,forests exhibit the highest CIPI(0.55),followed by shrublands(0.54),croplands(0.53),grasslands(0.51),and barelands(0.43).The Theil index analysis further demonstrates significant intra-group disparities,suggesting that extreme climatic events amplify CIPI heterogeneity.Moreover,the dominant environmental drivers differ among ecosystem types:the Palmer Drought Severity Index(PDSI)primarily constrains grassland productivity,solar radiation(SRAD)strongly influences shrub and cropland systems,whereas subsurface factors exert greater control in forested regions.This study provides a quantitative framework for evaluating climate-ecosystem interactions and offers a scientific basis for long-term ecological monitoring and security planning across the EQTP.展开更多
文摘The depositional environment of the sands of the cover formation is discussed. This study aims to determine the paleoenvironments of deposition of the sands of the cover formation in the Batéké Plateaus by studying sedimentary dynamics based on the description of lithological facies in the field and granulometric analyses in the laboratory. In the field, six (6) lithostratigraphic logs were surveyed and 42 sand samples were taken for laboratory analysis. In the laboratory, the samples underwent granulometric, sieving and sedimentometry analyses, after washing with running water using a 63 µm sieve. These analyses made it possible to determine the granulometric classes of the samples. The sieving results allowed to determine the granulometric parameters (mean, standard deviation, mode, median, skewness, flattening or kurtosis) using the method of moments with the software “Gradistat V.8”, granulometric parameters with which the granulometric facies, the mode of transport and the deposition environment were determined using the diagrams. Morphoscopy made it possible to determine the form and aspect of the surface of the quartz grains constituting these sands. Granulometric analyses show that these silty-clay or clayey-silty sands are fine sands and rarely medium sands, moderately to well sorted and rarely well sorted. The dominant granulometric facies is hyperbolic (sigmoid), with parabolic facies being rare. The primary mode of transport of these sands is saltation, which dominates rolling. The dispersion of points in the diagrams shows that these sands originate from two depositional environments: aeolian and fluvial. Morphoscopic analysis reveals the presence of clean rounded matt grains (RM), dirty rounded matt grains (RS), shiny blunt grains (EL) and shiny rounded grains (RL). The rounded matt grains exhibit several impact marks. The presence of dirty rounded grains with a ferruginous cement on their surface indicates that these sands have been reworked. These sands have undergone two types of transport, first by wind (aeolian environment) and then by water (fluvial environment).
基金supported by the National Natural Science Foundation of China (Grant Nos.91437219,41275075 and 41175005)the National Basic Research Program of China (Grant No.2013CB430203)
文摘Variation in the location of the South Asian High （SAH） in early boreal summer is strongly influenced by elevated surface heating from the Tibetan Plateau （TP） and the Iranian Plateau （IP）. Based on observational and ERA-Interim data, diagnostic analyses reveal that the interannual northwestward-southeastwaxd （NW-SE） shift of the SAH in June is more closely correlated with the synergistic effect of concurrent surface thermal anomalies over the TP and IP than with each single surface thermal anomaly over either plateau from the preceding May. Concurrent surface thermal anomalies over these two plateaus in May are characterized by a negative correlation between sensible heat flux over most parts of the TP （TPSH） and IP （IPSH）. This anomaly pattern can persist till June and influences the NW-SE shift of the SAH in June through the release of latent heat （LH） over northeastern India. When the IPSH is stronger （weaker） and the TPSH is weaker （stronger） than normal in May, an anomalous cyclone （anticyclone） appears over northern India at 850 hPa, which is accompanied by the ascent （descent） of air and anomalous convergence （divergence） of moisture flux in May and June. Therefore, the LH release over northeastern India is strengthened （weakened） and the vertical gradient of apparent heat source is decreased （increased） in the upper troposphere, which is responsible for the northwestward （southeastward） shift of the SAH in June.
基金supported by the National Key R&D Program of China (No. 2018YFC0309800)the National Natural Science Foundation of China (Nos. 91628301, U1606401, 41606069, 41776058)+2 种基金the Natural Science Foundation of Guangdong Province in China (No. 2017A030313243)the Chinese Academy of Sciences (Nos. Y4SL021001, QYZDY-SSWDQC005)the China Association of Marine Affairs (No. CAMAZD201714)
文摘Oceanic plateaus are large igneous provinces in the oceans,created by massive underwater eruptions,but their late-stage volcanism is poorly understood.With the addition of recent high-quality bathymetric data to existing data,286 secondary cones were discovered over Shatsky Rise oceanic plateau.These cones with steeper flank slopes(mean 6.1°±4.4°)and smaller sizes(102–1923 m in height)are morphologically distinct from the plateau,and they are thought to have formed after the main volcanic episodes.Cone height and characteristic height(420 m)are close to seamounts in the Pacific Ocean,whereas greater than those in the Atlantic Ocean.Mean flatness of Shatsky Rise’s cones(0.25±0.20)are similar to that of seamounts in both Pacific and Atlantic Oceans,but notably density in cone distribution(0.56 km^-3)and their mean slope are significantly lower than those of seamounts in the two oceans.Lower slopes of secondary cones within Shatsky Rise may be explained by higher effusion rates of remaining magma.Although cone formation was expected to have a link to rifting by seafloor spreading,weak relationship between cone orientation and magnetic anomaly pattern implies that the expectation is negative.Moreover,weak correlation between the cone height and depth indicates it is not true that volcanic cones grow taller when they occur closer to the massif summits with thicker oceanic crust,which was suggested as the increase in hydraulic pressure.Cone height and flatness are also not strongly related,implying that remaining magma supply was too limited to foster the cones to critical height.
文摘Taking Niyang River Basin as an example, applying with the indices of landscape pattern, the indices of ecological risk of ecosystems are calculated in this paper, which takes the value of ecological loss of main ecosystem as the evaluation standard and takes into account the impacts of probability or the velocity of main hazards and event of the ecosystem. And the grades of ecological risk are assessed. According to the results of assessment, the ecological risk grades of the basin are divided into five classes. From the first grade risk to the fifth grade risk, the values of regional risk indices gradually reduce. The first grade risk areas mainly distribute in Niyang river and its branches downstream and the surrounding areas of main towns. And the basin area of non-valley region and the headstream regions of the branches are the fifth grades risk areas. This evaluation results provide the basis to the regional sustainable development.
基金supported by the National Natural Science Foundation of China(Grant Nos.41871350,41571099)the Scientific and Technological Basic Resources Survey Project(Grant No.2017FY100900)。
文摘As one of the main non-zonal factors,the mass elevation effect(MEE)has significant impacts on both regional climates and mountain ecological patterns.In recent years,with the development of quantitative techniques and methods,quantitative studies on the MEE and its implication on mountain altitudinal belts have developed rapidly.However,some issues have not been solved yet,such as high errors in spatial temperature estimations and difficulties in the definition and extraction of intramountain base elevation.Moreover,there is still a lack of comparative studies on the MEE and its influence on treelines and snowlines as most studies were conducted on specific mountains or plateaus.To compare the MEE magnitudes of the Tibetan Plateau(TP)and the Bolivian Plateau(BP),we estimated the correspondent air temperatures and simulated the solar radiations based on MODIS surface temperature,station observation,and treeline data.Then,we analyzed the elevation of the 10℃isotherms on the two plateaus,the temperatures at the same elevation,and the solar radiations.According to the mechanism of the MEE and the relationship of solar radiation and treeline,we constructed treeline models for the two plateaus through a stepwise regression analysis by considering several influencing factors of the MEE(e.g.,air temperature and precipitation)and using solar radiation as its proxy.The results showed that:(1)the MEE magnitude on the TP is equivalent to that on the BP although the former is slightly higher than the latter;(2)the MEE strongly influences the highest treelines in the northern and southern hemispheres,which both occur on the two plateaus.Notably,the treeline distribution models based on solar radiation had higher accuracies than those models with parameters of temperature and precipitation(the adjusted R^(2)values were 0.76 for the TP and 0.936 for the BP),indicating that solar radiation can be used to quantify the MEE and its implications on treelines.Overall,the results of this study can serve as a basis for subsequent analyses on the MEE’s impact factors.
文摘Cryogenic wedges developed due to very cold,rather arid conditions during the maximum of the last cold event when the drying up of the neighboring China Sea resulted in the failure of the East Asian Monsoon.As the climate ameliorated and the Monsoon rains reappeared,ice-wedges developed.Further warming permitted thawing of the ice infillings accompanied by replacement of the ice by sediments partly from the host ground as well as from the surface by wind or sheet wash.In cases of extreme surface water flow on slopes after 10 ka B.P.,small baydjarakhs typically c.50 cm high developed,only to have the resulting hollows infilled by sediments carried by wind and/or sheet wash.These shallow structures form a network on top of many of the cryogenic wedges.This complex history makes dating the ages of the wedges difficult using OSL methodology.Unfortunately,past field work ignored the problem of the angle of the cut face to the direction of the wedge infilling when sampling the contents of the narrow wedges,resulting in potential contamination of the samples with the host sediment.Sampling of the larger deposits should be alright,but the likelihood of contamination makes the interpretation of the resulting OSL dates from the narrow wedges questionable.Primary wedges consisting of primary mineral infillings should still have similar OSL dates with depth for a given wedge,but the distinction between ice-wedge infillings and soil wedges is difficult since both can exhibit older dates of the infillings with depth.The available data suggests that ice-wedges were significantly more common than sediment-filled primary wedges.A protocol to avoid having to obtain large numbers of OSL dates by more careful field sampling and the use of grain size determinations is provided in the Appendix.
文摘In southern Asia,there are three large-scale wave-like mountains ranging from the Tibetan Plateau westward to the Iranian Plateau and the Armenian Plateau.On the southern side between plateaus,there are the Indian Peninsula and the Arabian Peninsula.What dynamic mechanisms form the directional alignment of the three plateaus with the two peninsulas remains a mystery.In the early stages of the Earth’s geological evolution,the internal structure of the Earth was that the center was a solid core,and the outmost layer was a thin equatorial crust zone separated by two thick pristine continents in polar areas,while the middle part was a deep magma fluid layer.Within the magma fluid layer,thermal and dynamic differences triggered planetary-scale vertical magma cells and led to the core-magma angular momentum exchange.When the core loses angular momentum and the magma layer gains angular momentum,the movement of upper magma fluids to the east and the tropical convergence zone(TCZ)drives the split and drift of two thick pristine continents,eventually forming the current combination of these plateaus and peninsulas and their wave-like arrangement along the east-west direction.Among them,the horizontal orthogonal convergence(collision)of upper magma fluids from the two hemispheres excited the vertical shear stress along the magma TCZ,which is the dynamic mechanism of mountain uplifts on the north side and plate subductions on the south side.To confirm this mechanism,two examples of low-level winds are used to calculate the correspondence between cyclone/anticyclonic systems generated by the orthogonal collision of airflows along the atmospheric TCZ and satellite-observed cloud systems.Such comparison can help us revisit the geological history of continental drift and orogeny.
基金supported by SOA Funds for Young Scientists(Grant Nos.1084-10)Special Funding for the Basic Scientific Research(Grant Nos.JG0706and JG0716)
文摘This study investigates the relationship between the hotspot-ridge interaction and the formation of oceanic plateaus and seamounts in the Southwest Indian Ocean.We first calculated the relative distance between the Southwest Indian Ridge(SWIR)and relevant hotspots on the basis of models of plate reconstruction,and then calculated the corresponding excess magmatic anomalies of the hotspots on the basis of residual bathymetry and Airy isostasy.The results reveal that the activities of the Marion hotspot can be divided into three main phases:interaction with the paleo-Rodrigues triple junction(73.6-68.5 Ma),interaction with the SWIR(68.5-42.7 Ma),and intra-plate volcanism(42.7-0 Ma).These three phases correspond to the formation of the eastern,central,and western parts of the Del Cano Rise,respectively.The magnitude and apparent periodicity of the magmatic volume flux of the Marion hotspot appear to be dominated by the hotspot-ridge distance.The periodicity of the Marion hotspot is about 25 Ma,which is much longer than that of the Hawaii and Iceland hotspots(about 15 Ma).
基金supported by the National Natural Science Foundation of China(No.42272013)the National Key Research and Development Project of China(2024YFF0807603,2023YFF0804501)+1 种基金the National Natural Science Foundation of China(Nos.42302017,41872006)the NSFC BSCTPES project(No.41988101).
文摘The Series Barbini(subfamily Cyprininae sensu lato)is the most species-rich group within the family Cyprinidae,primarily confined to warm regions of southern Eurasia and Africa.The distribution patterns and evolutionary history of Chinese cyprinins have been effectively shaped by the Cenozoic uplift of the Qinghai-Tibet Plateau and the evolution of the Asian monsoon.Here,we describe two new fossil fishes from the early and middle Miocene of the Lunpola Basin in central Qinghai-Tibet Plateau,China,preserving the ethmoid and the rear of the occipital regions of the neurocranium,infraorbitals,hyopalatine arch,abdominal vertebrae,and some dorsal-fin pterygiophores and unbranched fin rays.Through detailed morphological comparisons,these fossils show definite affinities to Cyprinidae according to the morphology of the neurocranium,vertebral column,and dorsal fin rays;and one of which is classified into the Series Barbini,while the other can only be assigned to the Cyprinidae family level.These findings reveal that the hinterland of the plateau of the early Neogene should have hosted cyprinin fishes of greater diversity than today.This also indicates a warm-temperate paleoclimate suitable for their survival during that period,consistent with the paleoenvironmental and paleoclimatical conditions reconstructed from the contemporaneous mammalian fossil and palynological evidences.
基金supported by the National Key Research and Development Program of China(Grants No.2024YFF0810500 and 2022YFD1900802)the National Natural Scientific Foundations of China(Grants No.41991232,42301016 and 42571034)the Hainan Provincial Natural Science Foundation of China(Grant No.424QN354).
文摘Accurate water budget closure is critical for sustainable water resource management facing increased pressures from climate change and human activities.Although error reduction methods for individual water balance components have advanced,persistent biases remain due to the independent development of datasets,impacting basin scale water budget balance.In this research,we analyzed the mathematical origin of the bias between water budget components and developed a new basin-scale water balance calibration method that redistributes errors across components while enforcing water balance constraints.Validation confirms systematic improvements,with reduced RMSE(Precipitation:-2.29 mm/month;ET:-1.34 mm/month)and increased R2 against in situ observations.Applied to the Jinghe River Basin(2000−2019),the calibrated data reveal declining precipitation(-1.70 mm/year)and evapotranspiration(-1.84 mm/year)alongside slightly increasing runoff(0.20 mm/year in basin depth),signaling a drying trend.Land cover changes—marked by cropland loss(-3,497 km^(2))and forest(+720 km^(2))and grassland(+2,776 km^(2))expansion—reflect improved water consumption requirements by ecosystem,raising concerns for water retention and ecosystem stability.The method is particularly effective for ungauged basins with sparse ground data and underscores the need for integrated land-water management to enhance long-term resilience.
基金financially supported by the National Natural Science Foundation of China (42477044,32171648 and U23A2017)the Hubei Provincial Science and Technology Program,China (2025AFD451 and 2022CFB030)。
文摘Insight into the carbon turnover in soil aggregates and density fractions is essential for reducing the uncertainty in estimating carbon pools on the Tibetan Plateau,and how they vary with land use type is unclear.In this study,the effect of land use type on carbon storage and fractionation was quantified based on organic carbon and its ^(13)C abundance at the microscale of soil aggregates and density fractions in Tibetan alpine ecosystems.The sequence of soil aggregate destruction in the land use types of plantation(13.1%)<shrubland(32.7%)<grassland(47.9%)<farmland(61.8%)shows that plantations strengthen the soil structure.Plantation land had a greater contribution of light fraction organic carbon(28.3%)but a lower contribution of mineral-associated organic carbon(40.6%)to the carbon stock compared to farmland(13.5 and 70.3%).Interestingly,plantation land enhanced the aggregational differentiation of organic carbon and ^(13)C in each density fraction,whereas no such phenomenon existed in the soil organic carbon.Carbon isotope analyses revealed that carbon transfer in the plantation land occurred from the light fraction in macroaggregates(–24.9‰)to the mineral-associated fraction in microaggregates(–19.9‰).When compared to the other three land use types,the low transferability of carbon in aggregates and density fractions in plantation land provides a stable carbon pool for the Tibetan Plateau.This study shows that plantations can mitigate global climate change by slowing carbon transfer and increasing carbon storage at the microscale of aggregates and density fractions in alpine regions.
基金supported by the National Natural Science Foundation of China(Grant Nos.424B2002,U23A2011)National Key R&D Program of China(Grant No.2024YFF0808603)Second Tibetan Plateau Scientific Expedition and Research(STEP)Program(Grant Nos.2024QZKK0500,2024QZKK0400).
文摘Glacial lake outburst floods(GLOFs)are increasingly frequent under warming and degradation,exerting profound impacts on regional ecosystems,geomorphology,and human systems.Ice-dammed lakes account for nearly 70% of GLOFs worldwide,yet their dynamics remain poorly understood in remote regions such as the interior Tibetan Plateau.Here,we present the first systematic assessment of the evolution and drainage of ice-dammed lakes across the region using multi-source satellite imagery.Between 1973 and 2024,the number of ice-dammed lakes increased from 256 to 323,while the total area declined from 22.66±0.93 km^(2) to 20.43±1.6 km^(2) due to repeated drainage and diminished reservoir capacity.Newly formed lakes tended to shift toward higher elevations.A total of 775 previously unreported GLOFs were detected based on abrupt lake area loss.Bayesian regression reveals a sharp rise in GLOF frequency,from an average of 11 GLOFs per year during 1990-1994 to 42.6 GLOFs per year during 2020-2024.Meanwhile,GLOF timing has shifted earlier by 9.07±3.71 days,and pre-drainage lake areas declined by 0.02±0.01 km^(2) compared to 1990.These findings highlight the evolving behavior of ice-dammed lakes in response to climate change and glacial recession,with important implications for regional cryospheric research and disaster mitigation.
基金funded by the National Natural Science Foundation of China(No.42274066),the Second Qinghai-Xizang Plateau Scientific Expedition and Research Program(STEP)(No.2019Q ZKK0701).
文摘The Kumkol Basin,situated in the northern margin of the Qinghai-Xizang Plateau,provides a unique window into understanding the dynamic mechanisms driving the plateau’s northern expansion.However,its formation and tectonic evolution remain poorly understood due to limited geophysical data in this region.In this study,we computed cross-correlations for the TT components of station-pairs with high signal-to-noise ratios to extract Love wave waveforms and further performed Lovewave ambient noise tomography to image the upper crustal shear-wave velocity structure of the Kumkol basin down to 10 km depth.Our seismic velocity model reveals that the Kumkol Basin has a sedimentary thickness exceeding 8 km,with its center located near the Arka Mountain on the southern side.This suggests that the basin was likely formed as a foreland basin in response to the uplift of the Qiman Tagh Mountain to the north.Additionally,integrated with seismic reflection data,our seismic velocity model images a detachment fault at the basin basement depth.We inferred that the Kumkol Anticlinorium at the basin’s center have been produced by multiple thrust faults converging into this detachment fault at 8–10 km depth following the Early to Middle Miocene uplift of the Qiman Tagh Mountain.This structural configuration indicates pulsed basinward deformation since the late Miocene,likely reflecting a tectonic regime shift from extrusion to distributed shortening in the northern Qinghai-Xizang Plateau.Our findings provide a high-resolution velocity model of the Kumkol Basin,offering critical insights into its structural evolution and supporting future resource exploration in this underexplored region.
基金supported by the CAS Pioneer Hundred Talents Program and Second Tibetan Plateau Scientific Expedition Research Program(2019QZKK0708)as well as the Basic Research Program of Qinghai Province:Lithospheric Geomagnetic Field of the Qinghai-Tibet Plateau and the Relationship with Strong Earthquakes(2021-ZJ-969Q).
文摘The National Geophysical Data Center(NGDC)of the United States has collected aeromagnetic data for input into a series of geomagnetic models to improve model resolution;however,in the Tibetan Plateau region,ground-based observations remain insufficient to clearly reflect the characteristics of the region’s lithospheric magnetism.In this study,we evaluate the lithospheric magnetism of the Tibetan Plateau by using a 3D surface spline model based on observations from>200 newly constructed repeat stations(portable stations)to determine the spatial distribution of plateau geomagnetism,as well as its correlation with the tectonic features of the region.We analyze the relationships between M≥5 earthquakes and lithospheric magnetic field variations on the Tibetan Plateau and identify regions susceptible to strong earthquakes.We compare the geomagnetic results with those from an enhanced magnetic model(EMM2015)developed by the NGDC and provide insights into improving lithospheric magnetic field calculations in the Tibetan Plateau region.Further research reveals that these magnetic anomalies exhibit distinct differences from the magnetic-seismic correlation mechanisms observed in other tectonic settings;here,they are governed primarily by the combined effects of compressional magnetism,thermal magnetism,and deep thermal stress.This study provides new evidence of geomagnetic anomalies on the Tibetan Plateau,interprets them physically,and demonstrates their potential for identifying seismic hazard zones on the Plateau.
文摘While the Ordos Basin is recognized for its substantial hydrocarbon exploration prospects,its rugged loess tableland terrain has rendered seismic exploration exceptionally challenging[1-3].Persistent obstacles such as complex 3D survey planning,low signal-tonoise ratio raw data,inadequate near-surface velocity modeling,and imaging inaccuracy have long hindered the advancement of seismic exploration across this region.Through a problem-solving approach rooted in geological target analysis,this research systematically investigates the behavioral patterns of nodal seismometer-based high-density seismic acquisition in loess plateau.Tailored advancements in waveform enhancement and depth velocity modelling methodologies have been engineered.Field validations confirm that the optimized workflow demonstrates marked improvements in amplitude preservation and imaging resolution,offering novel insights for future reservoir characterization endeavors.
基金supported by the National Natural Science Foundation of China(42202131 and 42177184).
文摘This study examines a 1.32 m thick sediment sequence from the Cunge sag pond in the Litang Basin,eastern Tibetan Plateau,to assess the seismicity of the Litang fault during the Holocene.High-resolution geochemical,grain size,magnetic susceptibility,and total organic carbon indicators are employed to obtain a continuous record of changes in elemental,physical,and biological properties within the profile to identify seismic events.The seismic event layer generally comprises two sedimentary rhythms:a lower coarse sand layer and an upper fine silt-clay layer.These layers represent rapid deposition associated with fault activity(Earthquake A)and slower deposition during calm periods or earthquake recurrence intervals(Seismic interval A).Through six^(14)C dating,five seismic events have been identified in the Cunge sag pond section:E1(before 3955 a B.P.),E2(3713-3703 a B.P.),E3(3492-3392 a B.P.),E4(2031-1894 a B.P.),and E5(1384-1321 a B.P.).E1-E4 had shown a good consistency with the paleo-earthquake recorded by the trench,and whereas E5 is a newly identified seismic event,further improving the continuous earthquake sequence of the Litang fault.Based on existing trench data and the seismic event record from the Cunge sag pond,a total of 11 paleo-earthquakes are identified along the Litang fault since the Holocene.The paleo-earthquake activity of the Litang fault exhibits a clustered pattern,with recurrence intervals of both long periods(1000 a)and short periods(500 a).Since 5000 a,the interval between strong earthquake recurrences gradually decreases,indicating an increasing risk of strong earthquakes along the Litang fault.This study presents a continuous record of paleo-earthquakes along the Litang fault,eastern Tibetan Plateau,and can enhance the understanding of regional seismic activity.
文摘Located on the Qinghai-Xizang Plateau,the Xizang Autonomous Region boasts exceptional solar energy resources.Today,sunlight is being converted into electricity by a 100 megawatt(MW)photovoltaic power station in Chabala Township,Quxu County,Lhasa.Built by Huadian(Quxu)New Energy Co.,Ltd,the project is at an average altitude of 4,000 meters above sea level.It has become a powerful driver of green development in the region,ushering in a new chapter of harmonious coexistence between humanity and nature.
基金funded by the Second Tibetan Plateau Scientific Expedition and Research(STEP)program(Grant No.2019QZKK0608).
文摘Global climate change is a pressing environmental challenge.Climate-induced migration highlights the severe impact of unsuitable climatic conditions.However,current research methods are limited in their ability to assess climate suitability for residents in high-altitude areas.In this study,we assess climate suitability across the Qinghai-Xizang Plateau from 1979 to 2018 and project future changes using four different Shared Socioeconomic Pathway(SSP)climate scenarios by constructing the Climate Suitability Index(CSI).The findings reveal a notable increase in CSI from 0.32 to 0.36 from 1979 to 2018.The primary factors contributing to the increased climate suitability are increasing annual mean precipitation(61.42%)and decreasing solar radiation(17.22%)from 1979 to 2018.Furthermore,the study forecasts a continued enhancement of climate suitability across all SSP scenarios,with SSP585 demonstrating the greatest improvement,followed by SSP370,SSP245,and SSP126.Although low oxygen levels at high altitudes remain a challenge,the overall improvement in climate suitability offers hope for people living at high altitudes to cope with climate change.
基金Under the auspices of the National Key Research and Development Program of China Science and Technology Cooperation Project of the Chinese and Russian Governments(No.2023YFE0111300)National Social Science Fund of China(No.23BGL204)Natural Science Foundation of Inner Mongolia(No.2022MS04001)。
文摘Prolonged droughts have emerged as a major impediment to the revitalization of pastoral regions worldwide because they significantly augment their susceptibility to the deleterious effects of global climate change,overgrazing,and land degradation.This study,conducted in 106 pastoral villages across 33 pastoral banners of Inner Mongolia Autonomous Region of China between August 2021 and October 2022,used a community resilience evaluation indicator system to assess drought resistance.By calculating a community resilience index,the research explored influencing factors and proposed countermeasures,aiming to enhance resilience to prolonged drought.The results revealed three key findings.1)Pastoral areas exhibited a limited degree of community resilience to drought disasters(overall score=0.28),with resilience levels forming a pyramid-shaped hierarchy.2)Dimensional analysis showed that resilience scores decreased sequentially across five domains:social(0.53)>cultural(0.44)>environmental(0.38)>economic(0.32)>management(0.27).These results highlight the crucial role of economic and management resilience in enhancing community resilience,particularly when accompanied by pre-and post-disaster government support and social security,both of which must be improved.3)Key factors influencing community resilience included geographical location,traffic accessibility,and frequency and severity of droughts.From a drought resilience perspective,targeted strategies and recommendations are proposed to provide novel and practical approaches for achieving sustainable development in pastoral areas and rural regions as a whole.
基金National Key R&D Program of China,No.2022YFF1302401National Natural Science Foundation of China,No.42271007。
文摘Ecosystems along the eastern margin of the Qinghai-Tibet Plateau(EQTP)are highly fragile and extremely sensitive to climate change and human disturbances.To quantitatively assess climate-induced ecosystem responses,this study proposes a Climate-Induced Productivity Index(CIPI)based on the Super Slack-Based Measure(Super-SBM)model using remote sensing data from 2001 to 2020.The results reveal persistently low CIPI values(0.47-0.53)across major ecosystem types,indicating widespread vulnerability to climatic variability.Among these ecosystems,forests exhibit the highest CIPI(0.55),followed by shrublands(0.54),croplands(0.53),grasslands(0.51),and barelands(0.43).The Theil index analysis further demonstrates significant intra-group disparities,suggesting that extreme climatic events amplify CIPI heterogeneity.Moreover,the dominant environmental drivers differ among ecosystem types:the Palmer Drought Severity Index(PDSI)primarily constrains grassland productivity,solar radiation(SRAD)strongly influences shrub and cropland systems,whereas subsurface factors exert greater control in forested regions.This study provides a quantitative framework for evaluating climate-ecosystem interactions and offers a scientific basis for long-term ecological monitoring and security planning across the EQTP.
