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This paper aims to update our understanding of the carbon cycle in the Himalayas, the most intense collisional orogeny globally, by providing new insight into its impact on Cenozoic climate cooling through the use of isotopic variations in both organic and inorganic carbon and an isotopic mass balance model. Our results from 20 selected hot springs show that the relative contributions of dissolved carbon from the mantle, metamorphic decarbonization, aqueous dissolution, and soil organic matter are approximately 2%, 82%, 6%, and 10%, respectively. Approximately 87% ± 5% of CO2 generated in the deep crust precipitates as calcite, while approximately 5.5% ± 1% of this carbon is converted to biomass through microbial chemosynthesis at depths less than 2 km. Our random forests approach yielded a metamorphic carbon flux from the entire Himalayan orogenic belt of approximately 2.7 ∼ 4.5 × 1012 mol/yr. The minor CO2 released into the atmosphere (2.5 ∼ 4.2 × 1011 mol/yr) is comparable to the carbon consumption driven by Himalayan weathering. This paper provides new insights into deep carbon cycling, notably that approximately 93% of deeply sourced carbon is trapped in the shallow crust, rendering orogenic processes carbon neutral and possibly acting as one of the major triggers of long‐term climate cooling in the Cenozoic. Plain Language Summary: Large‐scale deep metamorphic decarbonization and CO2 release into the atmosphere during continental collision orogenesis worldwide have had significant impacts on Cenozoic global climate change. However, the carbon sources and sinks and the mechanisms underlying their impacts on climate change are not fully understood. This paper reports the chemistry of aqueous solutions, carbon isotopic compositions of dissolved inorganic carbon (DIC) and dissolved organic carbon (DOC), and helium and carbon isotopic compositions of free gases from hot springs in southern Tibet. The carbon isotope fractionation model between gas and aqueous solutions revealed that the carbon released from depth underwent six different stages. Based on the random forests machine learning algorithm, we estimated the metamorphic carbon flux across the Himalayan orogenic belt. Furthermore, only a small fraction (7%) of deep carbon is eventually released into the atmosphere, and this volume is the same magnitude as the amount of carbon absorbed by silicate weathering on the Tibetan Plateau. This paper emphasizes that the carbon sequestration process in the upper crust may have resulted in nearly carbon‐neutral geological bodies in the Himalayan orogenic belt, thus playing a critical role in Cenozoic climate cooling. Key Points: Approximately 87% of deeply sourced carbon precipitates as calcite, while approximately 5.5% is sequestered as biomass in the shallow crustThe carbon flux across the Himalayan orogenic belt was estimated by the random forests approachCrustal thickening has attenuated long‐term deep carbon emissions from the Himalayas [ABSTRACT FROM AUTHOR]

The issue of rangeland governance and tenure in pastoral China has sparked significant controversy and discussion. Several models have been suggested, encompassing private, state and common property systems. However, what does the practical implementation of rangeland governance entail? A review of the history of rangeland governance and policy in Amdo, Tibet tells how land governance is constructed by pastoralists adapting existing norms, formulating rules in various contexts, and negotiating with various groups such as the monastery, religious organisations, and governmental authorities. The governance of rangeland in Amdo, Tibet is characterised by constant negotiations and contestations, including resistance from below, and is shaped by various processes in the real‐world context. Through the notion of assemblage, which involves bringing together an array of agents and objectives to intervene in social processes to produce desired outcomes and avert undesired ones, this paper adds to the existing body of research on land governance by examining how institutions are formed in the case of a hydroelectric dam on the land of the pastoralists. Consequently, the question arises: What does this mean for policy and practice for the rangelands of China? If hybrid rangeland governance is to be considered the prevailing practice, then what implications would this have for the framing of policies and their implementation? [ABSTRACT FROM AUTHOR]

Given the exponential increase in the number of refugees and displaced people worldwide, it has become critical to examine the experiences of refugees; particularly their identity, since it is an important marker of their adjustment to the new context. Besides other factors impacting their identity and adjustment, the role of the leader is important as it can impact the construction of refugee identities. This paper explores the construction and negotiation of Tibetan refugee identities through the identity entrepreneurship of the Dalai Lama, the spiritual and erstwhile political leader of the Tibetans. It is postulated that leaders are entrepreneurs of identity who shape identity construction and negotiation. With an emphasis on the social, political, and historical context, three kinds of sources are analysed using a discourse‐historical approach to understand how leaders function as entrepreneurs of identity across the various contexts and negotiate identity construction across the shifting contexts. First, 12 speeches by the Dalai Lama on 10 critical events in Tibetan history since 1959; second, six speeches by the Dalai Lama for Tibetan Uprising Day (1961–2009); and third, two international interviews (CNN, 2009; BBC, 2012). The analysis demonstrates that the identity entrepreneurship of the Dalai Lama has strong elements of protection towards the ingroup, that is, the Tibetan refugees, through the crafting of a collective sense of identity for Tibetans. The study sheds new light on the nature of refugee leadership, acknowledging the impact of the shifting nature of identity, from a native citizen to refugee; and the leader's identity entrepreneurship in these evolving and often malleable contexts. [ABSTRACT FROM AUTHOR]

Glacial debris flows occurring on the Tibetan Plateau consistently result in significant property damage and loss of human life. A comprehensive field investigation was conducted in Tianmo valley along the Sichuan‐Tibet Highway to reveal the dynamics of a debris flow that occurred on 11 July 2018. Furthermore, a depth‐averaged multiphase debris flow model was proposed and employed to reconstruct the characteristics of the debris flow. The model derivation, implementation, evaluation, and application were presented to demonstrate its performance. The Voellmy model was chosen because it adequately accounts for both basal frictional effects and the entrainment phenomenon. The entrainment processes, the ice melting, and the lubrication effect, were also taken into consideration. Based on the numerical results combined with field investigation data, the kinetic characteristics of the glacial debris flow were analyzed. The Tianmo valley has a small area, but the volume and erosion rate of debris flows were much larger than that of two‐phase debris flows in the same location due to ice melting. The simulation results demonstrated that the glacial debris reached a peak velocity of 20 m/s. Additionally, the volume of the debris flow increased by 50% due to the erosion over a short runout distance of approximately 4,000 m. This increase was a result of the high velocity and abundant entrainment sources on the slope. This study aims to improve understanding of the high velocity and destructive potential of debris flows in the Tianmo valley. Plain Language Summary: Debris flows frequently affect people or infrastructure due to their large volumes and high velocities. A detailed field investigation was taken in Tianmo valley, Tibet Plateau, China in this paper to reveal the dynamics of debris flow hazard chains. In addition, an optimized numerical model was proposed and used to analyze the kinetic characteristics of a glacial debris flow that occurred on 11 July 2018. The basal friction, debris erosion, and ice melting were taken into account in the numerical simulation. Based on the numerical results combined with field investigation data, the kinetic characteristics of the glacial debris flow were obtained. Simulated results indicated that the movement process of a glacial debris flow moved approximately 4,000 m, reaching a maximum velocity of 20 m/s and 50% more materials through erosion along its path. It is expected that this study can help to better understand the significant destructive force in the Tianmo valley and establish evacuation and rescue plans for communities in Tibet Plateau. Key Points: The kinetic characteristics of a glacial debris flow in Tibet were investigatedAn optimized depth‐averaged multiphase debris flow model was derived, implemented, and evaluatedThe Tianmo debris flow exhibited high velocity, large volume, and high erosion rates due to ice melting and sufficient entrainment sources [ABSTRACT FROM AUTHOR]

Saline lakes contributions to the carbon cycle is crucial to the Qinghai‐Tibetan Plateau (QTP) carbon budget. Here, based on the 8‐year direct measurement of CO2 flux over the Qinghai Lake (QHL) and 83 collected CO2 flux data estimated by pCO2 sampling from 45 lakes over the QTP, we identified the interannual variations of CO2 flux and its response to the extreme climate events. Results showed: (a) the QHL CO2 absorption weakened in the spring, autumn and winter and turn to CO2 emissions in the summer during 2013–2020; (b) with higher Ts and less precipitation, coupling of positive Pacific Decadal Oscillation (PDO) and El Niño enhanced the summer CO2 emissions; and (c) the PDO and ENSO had obvious superposition effect on the decrease of CO2 absorption in autumn. Our results show the potential mechanism of lake CO2 flux responses to extreme climate and further defines the significance of the QTP carbon budget and cycling. Plain Language Summary: The CO2 flux at the water‐air interface is especially important since it directly affects the accurate evaluation of the global carbon budget. However, lacking of long‐term continuous observation data left an undeniable gap on the interannual variations of CO2 flux and its respond to extreme climate events (the El Niño‐Southern Oscillation and Pacific Decadal Oscillation: ENSO and PDO) in saline lakes, although they are globally significant. Here, based on the 8‐year direct measurement of CO2 flux by eddy covariance system over the QHL and 83 collected CO2 flux data estimated by pCO2 sampling from 45 lakes over the QTP. This study found a weakening of CO2 absorption in the spring, autumn and winter, and an enhancing of CO2 emissions in the summer in QHL during 2013–2020, and first reported a notable transformation of carbon sink to source of saline lakes for responding to the extreme climate events. Moreover, the enhancing of CO2 emissions may be stronger in saline lakes than that in fresh lakes over QTP. The results firstly show the potential mechanism of lake CO2 flux responses to extreme climate and further defines the significance of the QTP carbon budget and cycling. Key Points: The QHL CO2 absorption weakened in spring, autumn and winter, and even turn to CO2 emissions in summer during 2013–2020In‐phase PDO and El Niño events enhanced the summer CO2 emissions in saline lake over QTPRising in Ts and decreasing in precipitation dominated the CO2 variations [ABSTRACT FROM AUTHOR]

The kinematics and deformation pattern along the Altyn Tagh fault (ATF), one of the largest strike‐slip faults on Earth is of great significance for understanding the growth of the Tibetan Plateau. However, the initial rupture along the ATF remains debated given the limited constraints on the depositional age of associated Cenozoic syntectonic strata. Here we investigated the syntectonic Cenozoic strata in the Xorkol Basin, associated with the strike‐slip faulting along the ATF. New uranium‐lead analyses of the carbonate deposits in the Paleogene strata yield dates of 58.9 ± 1.29 Ma, representing the initial rupture of the ATF. This first documented radioisotopic age coincides with the ca. 60 Ma onset timing of India‐Asia collision, highlighting its far‐field effect at the northern edge of the Tibetan Plateau. We infer that the deformation of the entire Tibetan Plateau started synchronously with the India‐Asia collision. Plain Language Summary: Carbonate U‐Pb dating techniques applied to rocks associated with the Altyn Tagh fault, a major fault in North Tibet, reveal that the fault started slipping about 58.9 million years ago, coinciding with the time when India collided with Asia. This finding provides new constraints on when and where this fault formed and suggests that the northern Tibetan Plateau started deformation earlier than previously thought. This result emphasizes that the entire Tibetan Plateau deformed simultaneously in the early Cenozoic. Key Points: Calcite U‐Pb dating yields ca. 59 Ma age for carbonate strata in the East Xorkol BasinXorkol Basin was a pull‐apart basin during the Paleocene due to the left‐lateral strike‐slip faulting along the Altyn Tagh faultWidespread Paleocene‐Eocene tectonism in Northern Tibet highlights the far‐field effect of the India‐Asia collision [ABSTRACT FROM AUTHOR]

A new species of Papaveraceae, Corydalis sunhangii, in the section Trachycarpae, is described and illustrated from Nyingchi City, Xizang, China. The new species has some resemblance to Corydalis kingdonis, but differs by radical leaves prominent, usually several, blade tripinnate (vs. insignificant, few, blade bi‐ to triternate); cauline leaf usually one, much smaller than radical leaves, usually situated in lower half of stem (vs. usually two, larger than radical leaves, concentrated in upper third of stem); racemes densely 13–35‐flowered (vs. rather lax, 4–11‐flowered); claw of lower petal shallowly saccate (vs. very prominently and deeply saccate); capsule oblong, with raised lines of dense papillae (vs. broadly obovoid, smooth). Phylogenetic analysis, based on 68 protein‐coding plastid genes of 49 samples, shows that C. sunhangii is not closely related to any hitherto described species, which is consistent with our morphological analysis. [ABSTRACT FROM AUTHOR]

The structural connectivity and kinematic relationship between the Altyn Tagh sinistral strike‐slip fault (ATF) and Qilian Shan fold‐and‐thrust belt along the north Tibetan margin east of 96°E is an important question for tectonicists interested in the evolving active deformation field of Central Asia and associated earthquake hazards of China's Hexi Corridor region. New results from a detailed 130‐km‐long N‐S magnetotelluric (MT) survey from the Qilian Shan to Beishan elucidates the locations and down‐dip orientations of major faults. Importantly, the results indicate that the Heishan‐Jinta'Nanshan fault system roots steeply into the lower crust, is unconnected to the Qilian Shan thrust wedge, and has reactivated the margin of the North China Craton and an older, regional ductile shear belt. The structurally linked ATF‐Heishan‐Jinta'Nanshan system defines a fundamental kinematic boundary in central Asia between the NE directed Qilian Shan thrust belt to the south and the eastwardly extruding Beishan‐Alxa Block to the north. Plain Language Summary: In this study, we present results of a comprehensive electrical resistivity survey conducted in the western Hexi Corridor region of China. The survey reveals significant sub‐surface faults and crustal boundaries, providing insights into the crustal structure between northernmost Tibet (Qilian Shan) and the Beishan. We document how the strike‐slip crustal boundary known as the Altyn Tagh Fault (ATF)‐Heishan‐Jinta'Nanshan system is steep and spatially unconnected to the Qilian Shan east of 98°E. It separates crustal blocks with contrasting motion histories; the southern block experiences compressional deformation, whereas the northern block accommodates extensional and transtensional deformation. Furthermore, the northeast trending ATF bends and converges into the more east‐west‐oriented Heishan‐Jinta'Nanshan system. We propose that this is a result of the Heishan‐Jinta'Nanshan system reactivating an older ductile shear belt and a mechanically weak boundary along the northwestern margin of the Precambrian North China Craton. Our study confirms the significance of inherited crustal structures in localizing continental interior reactivation and associated earthquake hazards. Key Points: A new detailed 3D resistivity model from Northern Tibet to the Southern Beishan clarifies the crustal structure in the NW Hexi CorridorThe Heishan fault system penetrates steeply to the lower crust and is unconnected to the Qilian Shan thrust wedgeCrustal thickening and mountain uplift in Qilian Shan is kinematically separated from eastward Beishan‐Alxa Block extrusion further north [ABSTRACT FROM AUTHOR]

Understanding lithospheric rheology is crucial in investigating tectonic evolution of intra‐continental tectonic boundary. Here, we use geodetic observations to infer lithospheric rheology across the northeastern Tibet based on a 2D viscoelastic model. Our findings reveal a lower‐crust viscosity of <1022 Pa·s underneath its margins, lower than those estimated underneath its vicinities. By comparing deformation patterns and lithospheric rheology here with those observed in the eastern Tibet, we propose that lateral variations in lower‐crust viscosity control deformation patterns and topographic gradients along the Tibet margins. The presence of low viscosity lower‐crust can lead to the development of contrasting topographic gradients and shape the plateau's geomorphology and deformation characteristics during outward growth of the Tibet. We here emphasize the subtle variations in the lower‐crust rheology between deforming blocks and the corresponding mountain ranges, which play an important role in orogeny along the intracontinental convergence boundary. Plain Language Summary: The Tibetan Plateau undergoes remarkable outward growth driven by the ongoing convergence between the Indian and Eurasian plates. Significant questions remain as to the mechanisms responsible for generating distinct topography and deformation patterns along the Tibet margins, particularly when it encounters surrounding rigid continental blocks. The presence of these blocks poses a unique challenge in understanding processes that shape the plateau's geomorphology and deformation characteristics. Here we use geodetic observations to infer the lithospheric rheology across the northeastern Tibet based on a 2D viscoelastic model. We show that the lower‐crust viscosity underneath the margin of northeastern Tibet is notably lower compared to those of underneath its surrounding areas. By comparing these findings with the distinct topography, deformation patterns, and lithospheric rheology observed across the eastern margin of Tibet, we propose that lateral variations in lower‐crust viscosity between active tectonic blocks control the formation of mountain range‐fronts. The weak lower‐crust underneath the mountain ranges exerts a significant influence on uplift dynamics, determining the location of the maximum surface uplift and topographic gradient. Key Points: We infer lithospheric rheology across the northeastern Tibet using geodetic observations based on a 2D viscoelastic modelThe interpretation of surface deformation patterns requires a low viscosity wedge underneath the margin of northeastern TibetThe maximum surface uplift is predicted where the lower‐crust viscosity is the lowest along the intra‐continental convergence boundary [ABSTRACT FROM AUTHOR]