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| 1 | Tibet,the Himalaya,Asian monsoons and biodiversity-In what ways are they related?显示文摘Prevailing dogma asserts that the uplift of Tibet, the onset of the Asian monsoon system and high biodiversity in southern Asia are linked, and that all occurred after 23 million years ago in the Neogene.Here, spanning the last 60 million years of Earth history, the geological, climatological and palaeontological evidence for this linkage is reviewed. The principal conclusions are that: 1) A proto-Tibetan highland existed well before the Neogene and that an Andean type topography with surface elevations of at least 4.5 km existed at the start of the Eocene, before final closure of the Tethys Ocean that separated India from Eurasia. 2) The Himalaya were formed not at the start of the India-Eurasia collision, but after much of Tibet had achieved its present elevation. The Himalaya built against a pre-existing proto-Tibetan highland and only projected above the average height of the plateau after approximately 15 Ma. 3)Monsoon climates have existed across southern Asia for the whole of the Cenozoic, and probably for a lot longer, but that they were of the kind generated by seasonal migrations of the Inter-tropical Convergence Zone. 4) The projection of the High Himalaya above the Tibetan Plateau at about 15 Ma coincides with the development of the modern South Asia Monsoon. 5) The East Asia monsoon became established in its present form about the same time as a consequence of topographic changes in northern Tibet and elsewhere in Asia, the loss of moisture sources in the Asian interior and the development of a strong winter Siberian high as global temperatures declined. 6) New radiometric dates of palaeontological finds point to southern Asia's high biodiversity originating in the Paleogene, not the Neogene. | Robert A. Spicer | 2017 | Plant Diversity2017，39，5： | 30 |
| 2 | Late Triassic sedimentary records in the northern Tethyan Himalaya:Tectonic link with Greater India显示文摘The Upper Triassic flysch sediments(Nieru Formation and Langjiexue Group)exposed in the Eastern Tethyan Himalayan Sequence are crucial for unraveling the controversial paleogeography and paleotectonics of the Himalayan orogen.This work reports new detrital zircon U-Pb ages and whole-rock geochemical data for clastic rocks from flysch strata in the Shannan area.The mineral modal composition data suggest that these units were mainly sourced from recycled orogen provenances.The chemical compositions of the sandstones in the strata are similar to the chemical composition of upper continental crust.These rocks have relatively low Chemical Index of Alteration values(with an average of 62)and Index of Compositional Variability values(0.69),indicating that they experienced weak weathering and were mainly derived from a mature source.The geochemical compositions of the Upper Triassic strata are similar to those of graywackes from continental island arcs and are indicative of an acidicintermediate igneous source.Furthermore,hornblende and feldspar experienced decomposition in the provenance,and the sediment became enriched in zircon and monazite during sediment transport.The detrital zircons in the strata feature two main age peaks at 225-275 Ma and 500-600 Ma,nearly continuous Paleoproterozoic to Neoproterozoic ages,and a broad inconspicuous cluster in the Tonian-Stenian(800-1200 Ma).The detrital zircons from the Upper Triassic sandstones in the study area lack peaks at 300-325 Ma(characteristic of the Lhasa block)and 1150-1200 Ma(characteristic of the Lhasa and West Australia blocks).Therefore,neither the Lhasa block nor the West Australia blocks likely acted as the main provenance of the Upper Triassic strata.Newly discovered Permian-Triassic basalt and mafic dikes in the Himalayas could have provided the 225-275 Ma detrital zircons.Therefore,Indian and Himalayan units were the main provenances of the flysch strata.The Tethyan Himalaya was part of the northern passive margin and was not an exotic terrane separated from India during the Permian to Early Cretaceous.This evidence suggests that the Neo-Tethyan ocean opened prior to the Late Triassic and that the Upper Triassic deposits were derived from continental crustal fragments adjacent to the northern passive continental margin of Greater India. | Huawen Cao Yong Huang Guangming Li Linkui Zhang Jianyang Wu Lei Dong Zuowen Dai Liu Lu | 2018 | Geoscience Frontiers2018，9，1： | 27 |
| 3 | Potentially dangerous glacial lakes across the Tibetan Plateau revealed using a large-scale automated assessment approach显示文摘Glacial lake outburst floods(GLOFs) are a major concern in the Himalaya and on the Tibetan Plateau(TP),where several disasters occurring over the past century have caused significant loss of life and damage to infrastructure. This study responds directly to the needs of local authorities to provide guidance on the most dangerous glacial lakes across TP where local monitoring and other risk reduction strategies can subsequently be targeted. Specifically, the study aims to establish a first comprehensive prioritisation ranking of lake danger for TP, considering both the likelihood and possible magnitude of any outburst event(hazard), and the exposure of downstream communities. A composite inventory of 1,291 glacial lakes(>0.1 km^2) was derived from recent remote sensing studies, and a fully automated and object assessment scheme was implemented using customised GIS tools. Based on four core determinates of GLOF hazard(lake size, watershed area, topographic potential for ice/rock avalanching, and dam steepness), the scheme accurately distinguishes the high to very high hazard level of 19 out of 20 lakes that have previously generated GLOFs. Notably, 16% of all glacial lakes threaten human settlements, with a hotspot of GLOF danger identified in the central Himalayan counties of Jilong, Nyalam, and Dingri, where the potential trans-boundary threat to communities located downstream in Nepal is also recognised. The results provide an important and object scientific basis for decision-making, and the methodological approach is ideally suited for replication across other mountainous regions where such first-order studies are lacking. | Simon Keith Allen Guoqing Zhang Weicai Wang TANDong Yao Tobias Bolch | 2019 | Science Bulletin2019，64，7： | 20 |
| 4 | Nd isotopic compositions of the Tethyan Himalayan Sequence in southeastern Tibet显示文摘The Himalayan orogen consists of three major lithologic units that are separated by two major north-dipping faults: the Lesser Himalayan Sequence (LHS) below the Main Central Thrust (MCT), the Greater Himalayan Crystalline Complex (GHC) above the MCT, and the Tethyan Himalayan Sequence (THS) juxtaposed by the South Tibet Detachment fault (STD) over the GHC. Due to widespread meta-morphism and intense deformation, differentiating the above three lithologic units is often difficult. This problem has been overcome by the use of Sm-Nd isotopic analysis. The previous studies suggested that the LHS can be clearly distinguished from the GHC and THS by their Nd isotope compositions. However, the lack of detailed and systematic Sm-Nd isotopic studies of the THS across the Himalaya in general has made differentiation of this unit from the nearby GHC impossible, as the two appear to share overlapping Nd compositions and model ages. To address this problem, we systematically sam-pled and analyzed Nd isotopes of the THS in southeastern Tibet directly north of Bhutan. Our study identifies two distinctive fields in a εNd -TDM plot. The first is defined by the εNd(210 Ma) values of -3.45 to -7.34 and TDM values of 1.15 to 1.29 Ga from a Late Triassic turbidite sequence, which are broadly similar to those obtained from the Lhasa block. The second field is derived from the Early Cretaceous meta-sedimentary rocks with εNd(130 Ma) values from -15.24 to -16.61 and TDM values from 1.63 to 2.00 Ga; these values are similar to those obtained from the Greater Himalayan Crystalline Complex in Bhutan directly south of our sampling traverse, which has εNd(130 Ma) values of -10.89 to -16.32 and Nd model ages (TDM) of 1.73 to 2.20 Ga. From the above observations, we suggest that the Late Triassic strata of the southeast Tibetan THS were derived from the Lhasa block in the north, while the Early Cretaceous strata of the THS were derived from a source similar to the High Himalayan Crystalline Complex or Indian craton in the south. Our interpretation is consistent with the existing palaeocurrent data and provenance analysis of the Late Triassic strata in southeastern Tibet, which indicate the sediments derived from a northern source. Thus, we suggest that the Lhasa terrane and the Indian craton were close to one another in the Late Triassic and were separated by a rift valley across which a large submarine fan was transported southward and deposited on the future northern margin of the Indian continent. | DAI JinGen YIN An LIU WenCan WANG ChengShan | 2008 | Science China Earth Sciences2008，51，9： | 19 |
| 5 | Cenozoic topography,monsoons and biodiversity conservation within the Tibetan Region:An evolving story显示文摘The biodiversity of the Himalaya,Hengduan Mountains and Tibet,here collectively termed the Tibetan Region,is exceptional in a global context.To contextualize and understand the origins of this biotic richness,and its conservation value,we examine recent fossil finds and review progress in understanding the orogeny of the Tibetan Region.We examine the deep-time origins of monsoons affecting Asia,climate variation over different timescales,and the establishment of environmental niche heterogeneity linked to topographic development.The origins of the modern biodiversity were established in the Eocene,concurrent with the formation of pronounced topographic relief across the Tibetan Region.High(>4 km)mountains to the north and south of what is now the Tibetan Plateau bounded a Paleogene central lowland(<2.5 km)hosting moist subtropical vegetation influenced by an intensifying monsoon.In mid Miocene times,before the Himalaya reached their current elevation,sediment infilling and compressional tectonics raised the floor of the central valley to above 3000 m,but central Tibet was still moist enough,and low enough,to host a warm temperate angiosperm-dominated woodland.After 15 Ma,global cooling,the further rise of central Tibet,and the rain shadow cast by the growing Himalaya,progressively led to more open,herb-rich vegetation as the modern high plateau formed with its cool,dry climate.In the moist monsoonal Hengduan Mountains,high and spatially extensive since the Eocene but subsequently deeply dissected by river incision,Neogene cooling depressed the tree line,compressed altitudinal zonation,and created strong environmental heterogeneity.This served as a cradle for the then newly-evolving alpine biota and favoured diversity within more thermophilic vegetation at lower elevations.This diversity has survived through a combination of minimal Quaternary glaciation,and complex relief-related environmental niche heterogeneity.The great antiquity and diversity of the Tibetan Region biota argues for its conservation,and the importance of that biota is demonstrated through our insights into its long temporal gestation provided by fossil archives and information written in surviving genomes.These data sources are worthy of conservation in their own right,but for the living biotic inventory we need to ask what it is we want to conserve.Is it 1)individual taxa for their intrinsic properties,2)their services in functioning ecosystems,or 3)their capacity to generate future new biodiversity?If 2 or 3 are our goal then landscape conservation at scale is required,and not just seed banks or botanical/zoological gardens. | Robert A.Spicer Alexander Farnsworth Tao Su | 2020 | Plant Diversity2020，42，4： | 14 |
| 6 | Metallogenesis within continental collision zones: Comparisons of modern collisional orogens显示文摘Modern collisional orogens represent the natural laboratory for the study of metallogeny in continental collision zones. The Pyrenees, Alps, Zagros and Himalaya are all associated with Neo-Tethyan subduction and represent the youngest collisional orogens on Earth. Here, we compare these four orogens in terms of their composition, architecture, tectonic evolution,and metallogenic systems. The four orogens can be divided into simple and composite types. Simple orogens are represented by the Pyrenees and the Alps, and are characterized by narrow linear shapes in plain view and symmetric structures in cross-section,are free of arc magmatism, and are associated with the Mississippi Valley Valley-type Pb-Zn and orogenic gold deposits. The mineral deposits that form in these simple collisional orogens are generally related to processes that occur in the middle and upper crust. In contrast, composite orogens, as exemplified by the Zagros-Iranian and Himalayan-Tibetan Plateaus, are associated with broad orogenic plateaus in plain view and asymmetrical structures in cross-section, record extensive arc magmatism in continental margins, and are associated with a variety of deposit types including carbonatite-related rare earth element(REE),porphyry Cu-Mo, orogenic Au, Mississippi Valley type Pb-Zn, and detachment-fault-related polymetallic deposits. Although the subduction of Neo-Tethys oceanic crust occurred before the creation of simple collisional orogens in the Pyrenees and the Alps,these areas do not show the record of continental arc magmatism. In contrast, the composite collisional orogens are associated with the development of huge continental margin arcs prior to continental subduction, and the subduction was followed by reactivation of the subduction-modified arc lithospheric material, generating the ore-forming systems in these regions. | Hongrui ZHANG Zengqian HOU | 2018 | Science China Earth Sciences2018，61，12： | 10 |
| 7 | Why ‘the uplift of the Tibetan Plateau’ is a myth显示文摘The often-used phrase‘the uplift of the Tibetan Plateau’implies a flat-surfaced Tibet rose as a coherent entity,and that uplift was driven entirely by the collision and northward movement of India.Here,we argue that these are misconceptions derived in large part from simplistic geodynamic and climate modeling,as well as proxy misinterpretation.The growth of Tibet was a complex process involving mostly Mesozoic collisions of several Gondwanan terranes with Asia,thickening the crust and generating complex relief before the arrival of India.In this review,Earth system modeling,paleoaltimetry proxies and fossil finds contribute to a new synthetic view of the topographic evolution of Tibet.A notable feature overlooked in previous models of plateau formation was the persistence through much of the Cenozoic of a wide east–west orientated deep central valley,and the formation of a plateau occurred only in the late Neogene through compression and internal sedimentation. | Robert A.Spicer Tao Su Paul J.Valdes Alexander Farnsworth Fei-Xiang Wu Gongle Shi Teresa E.V.Spicer Zhekun Zhou | 2021 | National Science Review2021，8，1： | 9 |
| 8 | Geochronological and geochemical constraints on the Cuonadong leucogranite, eastern Himalaya显示文摘First comprehensive investigations of the Cuonadong leucogranite exposed in North Himalayan gneiss dome of southern Tibet are presented in this study.The SIMS U–Pb ages of oscillatory zircon rims scatter in a wide range from 34.1 to 16.0 Ma, and the Cuonadong leucogranite probably emplaced at 16.0 Ma. High-precision ^(40)Ar/^(39)Ar dating on a muscovite sample yields an essentially flat age spectrum with consistent plateau and isochron ages, indicating that the Cuonadong leucogranite cooled below 450 °C at 14 Ma. Based on the youngest zircon U–Pb age and muscovite^(40)Ar/^(39)Ar age, the Cuonadong leucogranite experienced rapid cooling with a rate of 119 °C/Myr from 16 to 14 Ma. The geochronological data of this undeformed leucogranite also suggest that the ductile extension of the South Tibetan Detachment System in the eastern Himalaya ceased by ca. 14 Ma. Furthermore,the initial Sr–Nd isotopic compositions and Nd model ages demonstrate that the leucogranite was derived from metapelitic source within the Greater Himalayan Crystalline Complex. The distinct Ba depletion with high Rb/Sr ratios and negative Eu anomalies make it clear that the leucogranite melts were generated by breakdown of muscovite under fluid-absent conditions. | Jiajia Xie Huaning Qiu Xiujuan Bai Wanfeng Zhang Qiang Wang Xiaoping Xia | 2018 | Acta Geochimica2018，37，3： | 7 |
| 9 | Variation in Polyphenolics and Antioxidant Activity of Traditional Apple Cultivars from West Himalaya,Uttarakhand显示文摘Apple(Malus × domestica) is largely known for polyphenolic and antioxidant properties; however, systematic investigation in the apple growing in the Indian Himalayan region is not carried out. The present study therefore, attempts to quantify polyphenolics and antioxidant activities in three traditional apple cultivars namely 'Benoni', 'Fanny' and 'Rymer' growing at different locations of Uttarakhand(west Himalaya), India.Results revealed that phenolic(0.94–7.00 mg GAE·g^(-1)FW), flavonoid(1.02–9.86 mg QE·g^(-1)FW), flavonol(0.77–6.92 mg CE·g^(-1) FW), tannin(15.49–37.99 mg TAE·g^(-1) FW) and antioxidant activity(ABTS, 3.10–67.36; DPPH, 4.99–14.06; FRAP, 4.70–39.21 mmol AAE·kg^(-1)FW) varied significantly among the cultivars and maximum content was recorded in Rymer fruits of Mukhwa location. Altitude showed significant(P < 0.05) positive relationship with total phenolic(r = 0.895), flavonoid(r = 0.843), flavonol(r = 0.812), ABTS(r = 0.856) and FRAP activity(r = 0.830). Based on the results, it is concluded that among three cultivars, Rymer is one of the most promising sources of polyphenolic content and antioxidant activity and therefore, recommended for mass plantation at suitable locations in Uttarakhand for harnessing maximum potential. | BAHUKHANDI Amit DHYANI Praveen BHATT Indra D. RAWAL Ranbeer S. | 2018 | Horticultural Plant Journal2018，4，4： | 7 |
| 10 | Landslide susceptibility assessment of the region affected by the 25 April 2015 Gorkha earthquake of Nepal显示文摘Nepal was hit by a 7.8 magnitude earthquake on 25^(th) April,2015.The main shock and many large aftershocks generated a large number of coseismic landslips in central Nepal.We have developed a landslide susceptibility map of the affected region based on the coseismic landslides collected from remotely sensed data and fieldwork,using bivariate statistical model with different landslide causative factors.From the investigation,it is observed that most of the coseismic landslides are independent of previous landslides.Out of 3,716 mapped landslides,we used 80% of them to develop a susceptibility map and the remaining 20% were taken for validating the model.A total of 11 different landslide-influencing parameters were considered.These include slope gradient,slope aspect,plan curvature,elevation,relative relief,Peak Ground Acceleration(PGA),distance from epicenters of the mainshock and major aftershocks,lithology,distance of the landslide from the fault,fold,and drainage line.The success rate of 87.66% and the prediction rate of86.87% indicate that the model is in good agreement between the developed susceptibility map and theexisting landslides data.PGA,lithology,slope angle and elevation have played a major role in triggering the coseismic mass movements.This susceptibility map can be used for relocating the people in the affected regions as well as for future land development. | Amar Deep Regmi Megh Raj Dhital ZHANG Jian-qiang SU Li-jun CHEN Xiao-qing | 2016 | Journal of Mountain Science2016，13，11： | 7 |
| 11 | Paleoproterozoic granitic gneisses of the Dinggye and LhagoiKangri areas from the higher and northern Himalaya,Tibet:Geochronology and implications显示文摘Granitic gneisses have been widely found in crystalline rocks in the Dinggye area of the Higher Himalaya (HHM) and the LhagoiKangri area of the North Himalaya (NHM), Tibet. In the HHM, the gneisses intruded in the granulite-amphibolite facies metamorphosed sedimentary rocks, known as Nyalam group. In the NHM, the gneisses intruded in the amphibolite facies metamorphosed ones, known as LhagoiKangri group. These granitic gneisses are peraluminous monzonitic granites in terms of their mineral assemblage, and are considered as being derived from metamorphosed sedimentary rocks by anatexis based on the transitional relationship of the gneisses with their migmatitized wall rocks. Zircons are similar in crystal shape and interior structure from both gneisses. Most of them are euhedral or subhedral elongated prism-shaped transparent crystals, with fine oscillatory zoning, showing the magmatic genesis. Some of them are short prism-shaped and with relict core inherited from magma source and oscillatory zoning mantle crystallized from magma. SHRIMP U-Pb dating of zicons shows that both the granitic gneisses in the HHM and NHM are Paleoproterozoic (1811.6±2.9 Ma and 1811.7±7.2 Ma, respectively). These ages are similar to those (1815 to 2120 Ma) from granitic gneiss which is widely distributed in the Lesser Himalaya (LHM). The ages of inherited zircons (>2493.9±7.0 Ma, 2095.8± 8.8 Ma, 1874±29 Ma) exhibit the possible presence of several thermal events in Paleoproterozoic. All of the ages suggest the same India basement beneath the different units in Himalaya area, and do not support the idea that the HHM and NHM are accretionary terranes in Pan-Africa orogenic event. The fact that the basement in HHM is as old as or even younger than LHM is inconsistent with the presently prevalent orogenic models such as either extrusion of low-viscosity mid-crust or orogenic channel. | LIAO QunAn LI DeWei LU Lian YUAN YieMing CHU LingLin | 2008 | Science China Earth Sciences2008，51，2： | 5 |
| 12 | Plant endemism in the Nepal Himalayas and phytogeographical implications显示文摘Nepal is located in the central part of the greater Himalayan range with a unique series of mountain chains formed by recent mountain building geological events. As one of the youngest mountains in the world it contributes to diversity of plants and also provided barriers to and corridors through which plants migrated during the ice ages. The higher altitudinal variation with the high mountains, deep river valleys and lowland plains combine with the effects of the summer monsoon and dry winter result with an extraordinary diversity of ecosystems including flora and fauna in a relatively small land area. The existing checklists for Nepal record some 6000 species of flowering plants and about 530 ferns. However, the botanical experts estimate that numbers may go up to 7000 when the poorly known remote regions are fully explored. The information on plant endemism in Nepal Himalaya is not adequately known as Nepal is still struggling to complete long awaited Flora of Nepal project. Endemic species are confined to specific areas and are the first to be affected by land use and other global changes. We sought to explore the spatial distribution of endemic plant species in Nepal in relation to the consequences associated with climatic and geologic changes over time in the region with the help of published literature. It was found that the endemism showed marked spatial variation between open moist habitat and dry inner valleys, the former with higher endemism. The updated records showed 312 flowering plant species to be endemic to Nepal with higher endemism around the elevation of 3800e4200 m at sea level. The recent human population explosion, intensified deforestation, habitat fragmentation and modern day environmental changes are posing greater threats to endemic plant in Nepal. The conservation status and threats to these peculiar species are unknown. Nevertheless, environmental degradation and high poverty rates create a potent mix of threats to biodiversity in this landscape. | Achyut Tiwari Yadav Uprety Santosh Kumar Rana | 2019 | Plant Diversity2019，41，3： | 5 |
| 13 | 特提斯喜马拉雅多重基性岩浆事件:追溯新特提斯洋的生存时限(英文)显示文摘Processes accompanied the breakup of continents spreading of ocean floor and continent-ocean transition could trigger large scale melting of the mantle beneath the continent as well as the ocean,and produce mafic magmas with distinct | ZENG Ling-sen1),GAO Li-e1),HE Ke-jun2),TANG Suo-han1),GUO Chun-li2) 1).State Key Laboratory of Continental Tectonics and Dynamics,Institute of Geology,Chinese Academy of Geological Sciences,Beijing 100037,China | 2012 | 地球学报2012，33，S1： | 4 |
| 14 | Decreasing nutrient concentrations in soils and trees with increasing elevation across a treelineecotone in Rolwaling Himal, Nepal显示文摘At a global scale, tree growth in alpine treeline ecotones is limited by low temperatures. At a local scale, however, tree growth at its upper limit depends on multiple interactions of influencing factors and mechanisms. The aim of our research was to understand local scale effects of soil properties and nutrient cycling on tree growth limitation, and their interactions with other abiotic and biotic factors in a near-natural Himalayan treeline ecotone. Soil samples of different soil horizons, litter, decomposition layers, and foliage samples of standing biomass were collected in four altitudinal zones along three slopes, and were analysed for exchangeable cations and nutrient concentrations, respectively. Additionally, soil and air temperature, soil moisture, precipitation, and tree physiognomy patterns were evaluated. Both soil nutrients and foliar macronutrient concentrations of nitrogen(N), magnesium(Mg), potassium(K), and foliar phosphorus(P) decrease significantly with elevation. Foliar manganese(Mn) concentrations, bycontrast, are extraordinarily high at high elevation sites. Potential constraining factors on tree growth were identified using multivariate statistical approaches. We propose that tree growth, treeline position and vegetation composition are affected by nutrient limitation, which in turn, is governed by low soil temperatures and influenced by soil moisture conditions. | Simon DROLLINGER Michael MULLER Timo KOBL Niels SCHWAB Jurgen BOHNER Udo SCHICKHOFF Thomas SCHOLTEN | 2017 | Journal of Mountain Science2017，14，5： | 4 |
| 15 | 岩浆热液在喜马拉雅淡色花岗岩形成中的钡同位素证据显示文摘喜马拉雅淡色花岗岩是造山带晚期岩浆作用的特殊产物,是多种稀有金属元素的寄主岩石.目前对淡色花岗岩的认识有待深入,还不清楚岩浆流体对稀有元素富集的影响.本文测量了来自喜马拉雅造山带康巴穹窿的淡色花岗岩的钡同位素组成.淡色花岗岩的δ138/134Ba范围为-1.32‰~+0.12‰,远低于S型花岗岩和沉积物的δ138/134Ba值.它们的δ138/134Ba值及其和Nb/Ta的关系表明了岩浆演化过程中岩浆流体的参与.实验研究表明,岩浆流体的低δ138/134Ba很可能来自较大的深部岩浆储库出溶.这种流体不仅改变了淡色花岗岩的Ba同位素组成,而且还输送了大量有利于形成稀有金属矿床的流体活动元素.因此, Ba同位素数据为淡色花岗岩形成和演化以及稀有金属矿化过程提供了新的见解. | 黄方 白瑞霞 邓庚辛 刘小驰 李献华 | 2021 | Science Bulletin2021，66，22： | 4 |
| 16 | Cesium-rubidium mineralization in Himalayan leucogranites显示文摘This paper presents a study of a newly discovered pollucite-lepidolite-albite granite(PLAG)in the Himalayan leucogranite belt,which marks the first occurrence of pollucite,a major cesium silicate mineral,in the Himalayan orogenic belt(China).The rock appears at the northern part of the Gyirong pluton,coexisting with the tourmaline-bearing two-mica granite(TMG).Primary rare-metal minerals include lepidolite(Li),spodumene(Li),pollucite(Cs),cassiterite(Sn),and microlite(Ta).Micas,mainly lithian muscovite to lepidolite,contain 4.07 wt.%Li_2O and 0.76 wt.%Rb_2O on average.The average Li_2O content of the spodumene is 7.95 wt.%.Pollucite not only has an average Cs_2O content of 34 wt.%,but also has an elevated Rb_2O content of about 0.16 wt.%.Notably,this granite attains industrial grades for rare metals,specifically with Li_2O,Rb_2O,and Cs_2O contents of 0.49–1.19 wt.%,0.12–0.24 wt.%,and 0.69–2.33 wt.%,respectively.Dating results of magmatic accessory cassiterite and monazite indicated that the PLAG was formed at 19–18 Ma,slightly later than the TMG(22–20 Ma)of the Gyirong pluton.Thus,these two types of granites may form within the same magmatic system considering their pulsating intrusive contact,formation ages,and whole-rock and mineral chemical compositions.Furthermore,the abundant presence of pollucite suggests that the PLAG experienced high degrees of magmatic fractionation.In comparison to the Pusila spodumene pegmatite in the Himalaya and the Yashan topaz-lepidolite granite in Jiangxi,South China,the Gyirong PLAG exhibits different whole-rock and mineral compositions,resulting from differences in source materials and fractionation processes.Notably,the difference in fluorine(F)content may determine the degree of rare-metal element enrichment.The discovery of Gyirong PLAG highlights multiple stages and types of rare-metal mineralization in the Himalayan leucogranite belt,which is controlled by the South Tibetan Detachment System.The Cs-bearing geyserite deposit exposed along the Yarlung-Zangbo River,together with Himalayan leucogranites,constitutes two systems of rare-metal elements migration and enrichment.These two systems reflect the interaction among Earth systems across time and space,emphasizing how the Himalayan orogeny controls mineralization.As a result,the Himalayan leucogranite belt has considerable prospecting potential for cesium and rubidium resources and may be a crucial area for future exploration and resource utilization. | Fangyang HU Xiaochi LIU Shaoxiong HE Jiamin WANG Fuyuan WU | 2023 | Science China Earth Sciences2023，66，12： | 3 |
| 17 | Implications of tree species–environment relationships for the responsiveness of Himalayan krummholz treelines to climate change显示文摘Climate warming is expected to advance treelines to higher elevations. However, empirical studies in diverse mountain ranges give evidence of both advancing alpine treelines as well as rather insignificant responses. In this context, we aim at investigating the sensitivity and responsiveness of the near-natural treeline ecotone in Rolwaling Himal, Nepal, to climate warming. We analysed population densities of tree species along the treeline ecotone from closed forest stands via the krummholz belt to alpine dwarf shrub heaths(3700-4200 m) at 50 plots in 2013 and 2014. We quantified species-environment relationships, i.e. the change ofenvironmental conditions(e.g., nutrient and thermal deficits, plant interactions) across the ecotone by means of redundancy analyses, variation partitioning and distance-based Moran's eigenvector maps. In particular, we focus on explaining the high competitiveness of Rhododendron campanulatum forming a dense krummholz belt and on the implications for the responsiveness of Himalayan krummholz treelines to climate change. Results indicate that treeline trees in the ecotone show species-specific responses to the influence of environmental parameters, and that juvenile and adult tree responses are modulated by environmental constraints in differing intensity. Moreover, the species-environment relationships suggest that the investigated krummholz belt will largely prevent theupward migration of other tree species and thus constrain the future response of Himalayan krummholz treelines to climate warming. | Niels SCHWAB Udo SCHICKHOFF Birgit BURZLE Michael MULLER Jurgen BOHNER Ram Prasad CHAUDHARY Thomas SCHOLTEN Jens OLDELAND | 2017 | Journal of Mountain Science2017，14，3： | 3 |
| 18 | Petrogenesis and Tectonic Implications of the Paiku Leucogranites,Northern Himalaya显示文摘The Himalayan leucogranites provide insights into the partial melting behavior of relatively deeper crustal rocks and tectono-magmatic history of the Himalayan Orogen. The Paiku leucogranites of northern Himalaya can be subdivided into two-mica leucogranite(TML), garnet-bearing leucogranite(GL), cordierite-bearing leucogranite(CL), and tourmaline-bearing leucogranite(TL). All of them are high-K, peraluminous, calc-alkalic to alkali-calcic rocks. They are enriched in light rare earth elements(LREE) and large ion lithophile elements(LILE), and show pronounced negative anomalies of Sr, Ba, K and Ti, but positive anomalies of Nb and Rb. LA-ICP-MS U-Pb zircon dating of one TML, one GL, and two CL samples yielded variable 206Pb/238U ages ranging from 23.6 to 16.1 Ma, indicating the Paiku leucogranites underwent a low degree of partial melting process. Combining with previous studies, we suggest the Paiku leucogranites were derived from partial melting of metasedimentary rocks of the Higher Himalayan Sequence(HHS). The GL and TL mainly resulted from the muscovite-dehydration melting, whereas the TML and CL were mainly derived from the biotite-dehydration melting. Finally, it is concluded that the Paiku leucogranites were probably formed during the subduction of the Indian crust. | Zhengbin Gou Xin Dong Baodi Wang | 2019 | Journal of Earth Science2019，30，3： | 3 |
| 19 | Evolutionary origin of species diversity on the Qinghai-Tibet Plateau显示文摘The Qinghai-Tibet Plateau(QTP)sensu lato(sl)houses an exceptional species diversity in Asia.Todevelop a comprehensive understanding of species diversity in this fascinating region,we reviewed recentprogress from biogeographic,paleogeographic,paleontological and genomic research of both plants and animalsin the QTPsl.Numerous studies have been conducted to examine whether the QTPsluplift triggered theproduction of rich species diversity there,whether a Quaternary“unified ice sheet”eliminated plants and animalson the central plateau and how high-altitude species developed the extreme environment adaptations.Majordisputes arose about thefirst issue,mainly from different understanding of the QTP circumscriptions and relateduplift,inaccurate dating of molecular phylogenetic trees,and non-causal correlations between uplift and speciesdiversification.The QTPsluplift is spatially and temporally heterogeneous,and abundant fossils reported recentlysimilarly support such an asynchronous upheaval model across the entire region.Available phylogeographicstudies of alpine plants and animals suggested their glacial refugia in the central QTPsl,rejecting a unified icesheet during the Last Glacial Maximum.Genomic evidence from a limited number of alpine species has identifiednumerous candidate genes for high-altitude adaptation.In the future,more studies should be focused onspeciation and adaptation mechanisms of the alpine species in the QTPslbased on the cutting-edge methods. | Kang-Shan Mao Yi Wang Jian-Quan Liu | 2021 | Journal of Systematics and Evolution2021，59，6： | 3 |
| 20 | Recent treeline dynamics are similar between dry and mesic areas of Nepal, central Himalaya显示文摘Aims We investigated the treeline dynamics of two environmentally con-trasting areas in the Nepalese Himalaya to address the following questions:(i)Does the timing of establishment of the current tree-line differ between the two study areas,and can area-specific tree-line developments be identified?(ii)Do recruitment patterns and height growth indicate recent climate-driven treeline advance,fol-lowing the general prediction for the central Himalayan region,in the two study areas?Methods a dry-climate treeline dominated by Pinus wallichiana and a mesic-climate treeline with Abies spectabilis were selected for study.In each area,we sampled the size and age structure of the study spe-cies along three elevational transects(20-m wide)from the forest line to the tree species line crossing the treeline.We also sampled treeline trees from within and outside transects to reconstruct past treeline establishment dynamics.Important Findings Despite differences in moisture regimes,tree species and recent climate trends,our two study areas showed very similar treeline dynamics over the past six decades.In both areas,the recruitment of treeline trees indicates stationary treelines over the past six decades with the current treelines being dominated by trees that were established around 1990.the mesic area has experienced an overall climatic warming trend,and the stationary Abies treeline is hypothesized to be regulated by non-climatic factors,notably grazing.the dry area has not experienced warming but increased climatic variability and some very cool summers in the recent dec-ades may explain the stationary to weakly receding Pinus treeline,which appears more climatically controlled with decreased recruit-ment over the past decades and decreased growth towards higher elevations.In both areas,there is a potential for treeline advance,depending on future land use and climate change.our results highlight the importance of conducting treeline ecotone analyses for several sites or areas,and considering both climatic and non-climatic drivers of the treeline dynamics within each of these areas,for understanding regional treeline dynamics. | Krishna B.Shrestha Annika Hofgaard Vigdis Vandvik | 2015 | Journal of Plant Ecology2015，8，4： | 3 |
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