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The quest for the parent impact structure for Australasian tektites (AAT) has remained without solution for almost a century. The present paper doubts the plausibility of the recently proposed location of the impact site at the Bolaven volcanic field in Southern Laos by showing problems with most of the presented lines of evidence. The geochemical incompatibility of the AAT composition with a mixture of weathered basalts and Mesozoic sandstones that were proposed as source materials of AAT is demonstrated by a two‐component mixing calculation for major element oxides and the Nd‐Sr isotopic system. Deficiency of the basaltic component as a source of Ni, Co, Cr, and 10Be in AAT and inconsistency with trends observed for O and Pb isotopes are shown. The size of the putative crater, conclusiveness of a gravity anomaly identification, signs of complete crater burial by postimpact lava flows, and identification of proximal ejecta blanket are doubted. Remarks on the shortcomings of the current consensus location of an impact site for AAT in Indochina are presented. [ABSTRACT FROM AUTHOR]

This paper continues the publication of Aspidistra species newly discovered in the flora of Vietnam. It includes an illustrated description of A. pentagona, found in the northern part of the country. Detailed analytical color illustrations, data on morphology and ecology, phenology, tentative relationships, distribution and expected conservation status are provided for the discovered species. [ABSTRACT FROM AUTHOR]

In this paper, the authors quantitatively investigated the joint impact of the Arctic Oscillation (AO) and El Niño‐Southern Oscillation (ENSO) on vegetation net primary productivity (NPP) over Indo‐Myanmar in boreal winter from 1981 to 2018, and found that there is a significant in‐phase variation between them. When the warm ENSO co‐occurs with the positive AO, the NPP in more than 80% of the grids in the study region significantly increases by approximately 24 gC m−2. For the cold ENSO plus the negative AO, the regionally averaged NPP anomalies are approximately −10 gC m−2, and the local minimum is as low as −60 gC m−2. The combination of AO and ENSO can explain approximately 36% of the total variance of NPP in Indo‐Myanmar. The AO/ENSO linkages to the NPP are very likely due to regional precipitation anomalies through atmospheric circulation. In association with the positive (negative) AO, the Rossby wave, propagating eastward along the subtropical jet stream, brings an anomalous cyclone (anticyclone) over Indo‐Myanmar. This enhances (weakens) Indo‐Myanmar Trough, and resulting in more (less) regional precipitation. During the warm (cold) ENSO, through the Gill‐type response, an anomalous high (low)‐pressure appears in the lower and middle troposphere over Philippine‐South China Sea. The Walker circulation is also weaker (stronger) than normal. These are conducive to anomalous southerly (northerly) winds in Indochina. As a result, in the warm ENSO plus positive AO winters, the mean precipitation anomaly in Indo‐Myanmar increased by 27% as averaged for five data sets. In contrast, when the cold ENSO co‐occurs with negative AO, the precipitation is significantly reduced where the largest anomaly exceeds 100 mm in the ERA5. The precipitation changes are consistent with the local NPP anomalies, whereas the temperature does not seem to be a dominant limiting factor. Plain Language Summary: Vegetation is closely dependent on regional climatic conditions such as temperature and precipitation, whereas these meteorological elements are sensitive to large‐scale climate factors. Therefore, it is necessary to explore the vegetation drivers and underlying physical mechanisms. In this research, we focused on investigating the joint impact of the Arctic Oscillation (AO) and El Niño‐Southern Oscillation (ENSO) on vegetation net primary productivity (NPP) over Indo‐Myanmar in boreal winter from 1981 to 2018, the results show that the combination of AO and ENSO can explain approximately 36% of the total variance in regional NPP. The AO/ENSO linkages to the NPP are very likely due to regional precipitation anomalies through atmospheric circulation. In association with the positive (negative) AO, an eastward Rossby wave propagating along the subtropical jet stream brings an anomalous cyclone (anticyclone) over Indo‐Myanmar. During the warm (cold) ENSO, a southerly (northerly) wind anomaly prevails over Indochina via the Gill‐type response and weaker (stronger) Walker circulation than normal. As a result, when the warm (cold) ENSO co‐occurs with the positive (negative) AO winters, Indo‐Myanmar could experience more (less) precipitation than normal, which can lead to more NPP here. Key Points: There is a significant and robust in‐phase variation between the Arctic Oscillation (AO)/El Niño‐Southern Oscillation (ENSO) and net primary productivity (NPP) over Indo‐Myanmar in boreal winterThe combination of AO and ENSO can explain 36% of the total variance in NPPPrecipitation plays a critical bridge in teleconnection between AO/ENSO and local NPP and explains nearly 40% of the total variance in NPP [ABSTRACT FROM AUTHOR]

Vietnam contains complex faults coupled with a diffuse igneous province that has been active since the mid-Miocene. However, existing fault maps demonstrate little consensus over the location of Neogene basalt flows and relative ages of mapped faults, which complicates interpretations of tectonic model for the evolution of Indochina. This paper identifies discrete tectonic blocks within Vietnam and aims to define the Neogene-Recent tectonic setting and kinematics of south-central Vietnam by analyzing the orientation, kinematics, and relative ages of faults across each block. Fault ages and relative timing are estimated using cross-cutting relationships with dated basalt flows and between slickenside sets. Remote sensing results show distinct fault trends within individual blocks that are locally related to the orientations of the basement-involved block-bounding faults. Faults observed in the field indicate an early phase of dip-slip motion and a later phase of strike-slip motion, recording the rotation of blocks within a stress field. Faulting after the change in motion of the Red River Fault Zone at -16 Ma is inferred, as faults cross-cut basalt flows as young as -0.6 Ma. Strike-slip motion on block-bounding faults is consistent with rotation and continuous extrusion of each block within south-central Vietnam. The rotation of the blocks is attributed to the "continuum rubble" behavior of small crustal blocks influenced by upper mantle flow after the collision between India and Eurasia. We infer a robust lithospheric-asthenospheric coupling in the extrusion model, which holds implications for other regions experiencing extrusion even in the absence of a free surface. [ABSTRACT FROM AUTHOR]

This paper examines the changes of El Niño–Southern Oscillation (ENSO) associated winter rainfall relationship in Southeast Asia (SEA) in the historical period (1981–2010) and future period (2071–2100) based on the Coupled Model Intercomparison Project Phase 6 (CMIP6) models simulations. Twenty general circulation models (GCMs) are chosen from the Scenario Model Intercomparison Project (ScenarioMIP) highest emission scenario—Shared Socioeconomic Pathway (SSP) 5‐8.5. This study focuses only on the GCMs that have been able to replicate the consistent associated patterns observed, referred to as "teleconnection‐consistent models" (TCMs). During historical period, ENSO has significant negative association with SEA winter rainfall, particularly over Indochina mainland, Maritime Continent (MC) and northern Borneo. The significant negative‐associated teleconnection affected area has increased under future climate, particularly over southern part of South China Sea (SCS). The weakening of south westerlies at Western North Pacific (WNP) centred near 20°N reduces the moisture transport from Indochina into south of China, increase the negative correlated affected area in the SEA regions above equator. The northeasterlies/easterlies that prevailed from the WNP anticyclone (AC) brings significant moisture flux into southern Borneo, causing increment of significant positive‐associated moisture flux convergence to that region. The weakening of upward motion in TCM results in less warm and moist air rising over SEA MC, reducing the rainfall availability. The 1° eastward expansion of WC downward branch eastern edge leads to suppression of convective activities, increasing the dry affected area. The results suggest that the ENSO has a larger influence on the negative‐associated SEA rainfall and atmospheric circulation in the December–January–February (DJF) late‐21st century when compared to the 1980–2010. [ABSTRACT FROM AUTHOR]

Continental‐scale shear zones in Indochina record Cenozoic tectonic processes in SE Asia. Previous extrusion models link these shear zones to northward indentation of the Indian continent and conflict with distributed Oligocene conjugate strike‐slip pairs, formed by E‐W‐directed compression (present coordinates). This paper presents evidence of Oligocene shearing along the Mogok Metamorphic Belt in Myanmar, the western boundary of the Indochina block. The Kyanigan quarry at northern Mogok Metamorphic Belt exposes paragneiss, marble and quartzite schist with E‐W striking, which would be dragged from N‐S striking foliations of the main Mogok Metamorphic Belt by right‐lateral shearing of the brittle Sagaing Fault. After restoration, right‐lateral shearing 'σ' structures, cored with garnet, in paragneiss in the Kyanigan quarry are consistent with 'σ' and 'δ' structures in the Moulmein granitic mylonite to the south. U–Pb ages of metamorphic zircon of a sheared paragneiss and a leucogranite, cross‐cutting shear foliation in the Kyanigan quarry, and a biotite 39Ar‐40Ar age of mylonite at Moulmein constrain dextral shearing to 33–25.4 Ma, coeval with other 31–24.5 Ma shear zones in Indochina. The eleven NW‐striking left‐lateral shear zones and N‐S to NE‐striking right‐lateral shear zones define Oligocene conjugate fault patterns in Indochina. After restoration of ~80–45° clockwise rotation, these Oligocene conjugate shear zones, coupled with the anticlinal configuration of the Xuelongshan and Doi Inthanon‐Doi Suthep domes, reflect approximate N–S‐directed shortening. These structures to the north with coeval Myanmar‐Sumatra magmatic arc to the south demonstrate that they correspond to back‐arc contraction during northward subduction of the Indian Ocean. Oligocene continental‐scale intra‐continental shearing may be triggered by syn‐subduction compression in SE Asia. [ABSTRACT FROM AUTHOR]

Modelling rainfall extremes and dry periods over the Southeast Asia (SEA) region is challenging due to the characteristics of the region, which consists of the Maritime Continent and a mountainous region; it also experiences monsoonal conditions, as it is located between the Asian summer monsoon and the Australian summer monsoon. Representing rainfall extremes is important for flood and drought assessments in the region. This paper evaluates extreme rainfall climatic indices from regional climate models from CORDEX Southeast Asia and compares them with the results of high‐resolution global climate models with a comparable spatial resolution from the HighResMIP experiment. Observations indicate a high intensity of rainfall over areas affected by tropical cyclones and long consecutive dry day periods over some areas in Indochina and the southern end of Indonesia. In the model simulations, we find that both coupled and sea surface temperature‐forced HighResMIP model experiments are more similar to the observations than CORDEX model results. However, the models produce a poorer simulation of precipitation intensity‐related indices due to model biases in the rainfall intensity. This bias is higher in CORDEX than in HighResMIP and is evident in both the low‐ and high‐resolution HighResMIP model versions. The comparable performances of HighResSST (atmosphere‐only runs) and Hist‐1950 (coupled ocean–atmosphere runs) demonstrate the accuracy of the ocean model. Comparable performances were also found for the two different resolutions of HighResMIP, suggesting that there is no improvement in the performance of the high‐resolution HighResMIP model compared to the low‐resolution HighResMIP model. [ABSTRACT FROM AUTHOR]

This paper continues the publication of Aspidistra species newly discovered in the flora of Vietnam. It includes illustrated diagnosis of two species new to science, A. liliiflora and A. sessilistigma found in northern and central parts of the country. Detailed analytical color illustrations, data on morphology, ecology, phenology, tentative relationships and distribution are provided for both discovered species. [ABSTRACT FROM AUTHOR]

This paper continues the publication of Aspidistra species newly discovered and reported in the flora of Vietnam. It includes illustrated diagnosis of one species new for science, A. angustata Aver., K.S. Nguyen & Tillich and notes on two species, A. chunxiuensis C.R. Lin & Yan Liu, and A. guangxiensis S.C. Tang & Yan Liu newly recorded in the country. Color illustrations, new or updated data on morphology, ecology, phenology, tentative relationships, distribution and conservation status are provided for all three taxa. [ABSTRACT FROM AUTHOR]

This paper continues the publication of newly obtained results from a continuing taxonomic investigation of the genus Aspidistra in Laos and Vietnam. It includes illustrated diagnoses of two new species, A. melanaster Aver., K.S. Nguyen & Tillich, A. obliqua K.S. Nguyen & Aver., two new varieties, A. semiaperta Aver. & Tillich var. globulifera Aver., K.S. Nguyen & Tillich, A. lutea Tillich var. luteo‐rubra K.S. Nguyen, Aver. & Tillich, and notes on two species, A. austroyunnanensis G.W. Hu, Lei Cai & Q.F. Wang and A. hekouensis H. Li, C.L. Long & Bogner newly recorded in the flora of Vietnam. Color illustrations, new or updated data on morphology, ecology, phenology, tentative relationships, distribution and conservation status are provided for all the mentioned taxa. [ABSTRACT FROM AUTHOR]

The paper examines how land and forest management policies were elaborated in French Indochina circa 1900–40. It places their development in the context of a scientific and economic discourse about the value of land and forest resources, the most appropriate ways in which they might be exploited and the relationship between colonial science and indigenous knowledge. By focusing on debates and laws relating to the development of small-scale and plantation farming systems (Land Code legislations) and forest management and exploitation (Forest Code legislations) the paper seeks to ground arguments about Western conceptions of the “tropics” within a discussion of national policy development and impacts. Focusing primarily on Cochinchina and Annam (southern and central Vietnam) and drawing on materials from French archives, the paper shows how changes in both attitudes and legislation have had lasting consequences on systems of property rights in forest management and on the place and status of indigenous peoples in Indochina. [ABSTRACT FROM AUTHOR]

Abstract This paper examines the fieldwork undertaken by the distinguished French geographer Pierre Gourou (1900–99) in the Tonkin Delta (Red River Delta) of northern Vietnam in the 1920s and 1930s, and his wider configuration of “the tropical world” as a distinct space of knowledge and radical otherness. Gourou's fieldwork endeavours in French Indochina are interpreted in the light of recent work on “tropicality”: the idea that “the tropics” need to be understood as a western cultural construction and colonising discourse that essentialised the hot, wet regions of the world, and exalted the temperate world over its tropical counterpart. The paper focuses on Gourou's monumental 1936 study Les paysans du delta tonkinois, étude de géographie humaine. It is argued that in this study, and his later comparative work on the tropics, Gourou elaborated a distinct geographical variant of tropicality, but one that, ultimately, reinforced the essentialist logic and momentum of this discourse. Particular attention is paid to the geographical ideas, fieldwork techniques and discursive strategies that Gourou used in his 1936 study, and the French colonial context in which he worked. The article shows how Gourou appealed to western reason and science as tools of study, identified overpopulation as the key problem facing the Tonkin Delta, and suggested that colonial practices of modernisation had a limited place and ineffectual role in the rice plains of the region. [ABSTRACT FROM AUTHOR]

Following the termination of seafloor spreading in the South China Sea (SCS) basin, abundant intraplate volcanism widely spreads in the Indochina block, SCS basin, and Leiqiong area, forming the Southeastern Asian Basalt Province (SABP). The geodynamic origin of the SABP has long been enigmatic and debated. Here, we present a high‐resolution 3‐D upper mantle S‐wave velocity model in the region by conducting earthquake‐based surface wave tomography with seismic data collected across Southeast Asia. The resultant images depict a plume‐like structure beneath the central area of the SABP, characterized by a continuous, sub‐vertical low‐velocity column in the upper mantle. Our new findings, combined with previous geochemical and geodynamic evidence, suggest that the extensive post‐spreading intraplate volcanism within the SABP is likely induced by this focused mantle upwelling, which could be further traced down to the core‐mantle boundary as inferred by existing global velocity models. Plain Language Summary: The well‐known Southeastern Asian Basalt Province (SABP), which covers an extensive area of the South China Sea (SCS) and surroundings, is characterized by voluminous volcanism after the cessation of seafloor spreading in the SCS basin. However, the geodynamic mechanism responsible for the formation of the SABP remains debated and not well understood. In this study, we build a high‐resolution 3‐D seismic velocity model in the region utilizing multiple sources of seismic data collected throughout Southeast Asia. We find a distinct plume‐shaped low‐velocity anomaly in the upper mantle beneath the central region of the SABP. Combining with previous geochemical and geodynamic research results, we interpret that the abundant intraplate volcanism within the SABP may be contributed by the underlying focused mantle upwelling. This mantle upwelling, as evidenced in previous global seismic velocity models, could be further traced down to the core‐mantle boundary (∼2,900 km below the Earth's surface). Our tomographic images provide valuable insights into the origin and mantle dynamics related to the young intraplate volcanism that occurred in Southeast Asia. Key Points: A high‐resolution 3‐D upper mantle S‐wave velocity model surrounding the South China Sea is constructedA continuous, low‐velocity column is imaged beneath the central region of the Southeastern Asian Basalt ProvinceThe post‐spreading intraplate volcanism within the Southeastern Asian Basalt Province is likely induced by the focused mantle upwelling [ABSTRACT FROM AUTHOR]

Using the private papers of Lord Killearn in conjunction with official government documents from the British national archives and the French colonial archives, this article builds upon previous historical scholarship to highlight the importance of Killearn's South-East Asian diplomacy to the resolution of the international food crisis following the Second World War. As Britain's senior diplomat in South-East Asia Killearn had little choice but to become entangled in various international disputes often centred upon French Indo-China - Killearn's failure to do otherwise would not have preserved adequate international rice supplies. Therefore this article not only demonstrates the magnitude of Killearn's concern for South-East Asian rice production during the immediate post-war food crisis but it also reveals the depth of Killearn's frustration towards the chaotic priorities emanating from French Indo-China, and thus it substantiates a more significant and complex understanding of Killearn's diplomatic mission to South-East Asia than has been formerly stated. [ABSTRACT FROM AUTHOR]

Some scholars have explained colonial policies as the outgrowth of the need to provide profits and prestige for the motherland. Others have linked policymaking to the use of colonial space as experimental laboratories of modernity; while others assert that the overseas was a terrain for finding solutions to some of the political, social and aesthetic problems which were affecting France at the time. In contrast, this paper traces how colonial policies can be explained at the level of individual colonial administrators. It does so not only by reference to the social backgrounds of officials, but also their inner “psychic processes.” This study addresses the colonial tendency to imagine cross-identification between France and the colony. It presents three case studies of colonial officials in Indochina to investigate how administrators' perceptions of France became projected onto the colonies, and how one of them incorporated within himself some of the attributes of the colonized, an example of introjection. It is argued that these processes had an impact on policymaking. My theoretical goal with this piece was to apply a psychoanalytic approach to the study of the empire. [ABSTRACT FROM AUTHOR]

Aim: Understanding the biotic and abiotic mechanisms underlying the generation and maintenance of biogeographic transitions represent long‐standing topics in evolutionary biology. The Isthmus of Kra (IOK) divides Sundaland and Indochina and constitutes a poorly characterized terrestrial biogeographic transition. Here we looked at population genetic structure of three species that are distributed across the IOK to gain insights into the drivers that have shaped this transition and regional diversification patterns. Location: Tropical east Asia: Sundaland and Indochina. Taxa: Callosciurus caniceps, Tamiops mcclellandii, and Dremomys rufigenis‐ornatus species complex (Mammalia: Rodentia: Sciuridae). Methods: We generated complete mitogenomes and sequences of 11 nuclear intron fragments from 61 and 67 museum specimen samples, respectively. We assessed population structure by constructing Maximum Likelihood mitogenome phylogenies (IQTREE2), and nuclear marker haplowebs and conspecificity matrices (HaplowebMaker and CoMa). We estimated divergence dates through Bayesian phylogenetic inference (BEAST2) and put these results in the context of climatic and geological history. Results: High levels of mitochondrial and nuclear divergence were identified across the IOK in all three squirrels. Lineage turnover was consistent with the two major mammal species distribution transitions near the Kangar‐Pattani Line and at the juncture between the Thai‐Malay peninsula and the mainland. Divergence of mitochondrial lineages across Kra was estimated in the late Pliocene/ early Pleistocene for all three taxa. Older Miocene/Pliocene divergences were estimated within Indochina in D. rufigenis‐ornatus and T. mcclellandii, which were paraphyletic. Main Conclusions: Sundaic and Indochinese populations have possibly diverged in allopatric habitat refugia in or around mountains during periods of increased aridity and evergreen forest contraction. Ecological differences and/or topography might have influenced genetic differentiation during periods of rainforest expansion. Alternative hypotheses remain to be tested with more informative nuclear markers and additional geographic sampling. [ABSTRACT FROM AUTHOR]

Numerous insects including pests and beneficial species undertake windborne migrations over hundreds of kilometers. In East Asia, climate-induced changes in large-scale atmospheric circulation systems are affecting wind-fields and precipitation zones and these, in turn, are changing migration patterns. We examined the consequences in a serious rice pest, the brown planthopper (BPH, Nilaparvata lugens) in East China. BPH cannot overwinter in temperate East Asia, and infestations there are initiated by several waves of windborne spring or summer migrants originating from tropical areas in Indochina. The East Asian summer monsoon, characterized by abundant rainfall and southerly winds, is of critical importance for these northward movements. We analyzed a 42-year dataset of meteorological parameters and catches of BPH from a standardized network of 341 light-traps in South and East China. We show that south of the Yangtze River during summer, southwesterly winds have weakened and rainfall increased, while the summer precipitation has decreased further north on the Jianghuai Plain. Together, these changes have resulted in shorter migratory journeys for BPH leaving South China. As a result, pest outbreaks of BPH in the key rice-growing area of the Lower Yangtze River Valley (LYRV) have declined since 2001. We show that these changes to the East Asian summer monsoon weather parameters are driven by shifts in the position and intensity of the Western Pacific subtropical high (WPSH) system that have occurred during the last 20 years. As a result, the relationship between WPSH intensity and BPH immigration that was previously used to predict the size of the immigration to the LYRV has now broken down. Our results demonstrate that migration patterns of a serious rice pest have shifted in response to the climate-induced changes in precipitation and wind pattern, with significant consequences for the population management of migratory pests. [ABSTRACT FROM AUTHOR]

From mid‐May to late June, the eastward propagation of some mid‐tropospheric cyclones (MTCs) originating in the Bay of Bengal (BOB)‐Burma (BUM) region across northern Indochina and southwest China to East Asia are observed. From 1979 to 2016, 137 MTCs were identified for the BOB‐BUM region. Eighty‐eight MTCs were trapped over northern Indochina, but 49 were propagated by the southwesterly flow of the BOB mid‐tropospheric trough to reach East Asia. Thirty‐one moved across Taiwan, but 18 did not. Eventually, all these MTCs moved to Okinawa. The former group of rainstorms produced rainfall ≥100 mm·day−1 over Taiwan, while 44 rainstorms generated rainfall ≥50 mm·day−1 over Okinawa. The 49 eastward propagating through‐Indochina MTCs exhibited the following salient features: (a) initial formation mostly occurred in the mid‐troposphere ahead/within the BOB trough in the morning over the BOB, but in the afternoon‐evening over BUM. (b) The eastward propagating BOB‐BUM MTCs underwent two descending processes: descending one mandatory level 6 hr after formation, and descending again from 700 to 925 hPa over southeastern China to interact with a low‐level cyclonic shear flow. (c) Intensified (weakened) by dipole anomalous circulation cells, the confluent monsoon southwesterly flow west (east) of Taiwan facilitated the merger of the MTC with a local front. (d) Rainfall produced by rainstorms over Taiwan/Okinawa was maintained by the intensified convergence of water vapour flux toward Taiwan/Okinawa. This hydrological process was stronger toward Taiwan than Okinawa and generated more rainfall in the former region. The impact of the BOB‐BUM MTC on East Asian weather is confirmed by this study. [ABSTRACT FROM AUTHOR]

The tribe Acanthoplectrini (Myrmeleontidae: Dendroleontinae) includes a group of antlion genera widely distributed across the Australasian and Oriental regions. The intergeneric and interspecific relationships between or within the Australian and Oriental lineages of this tribe as well as their historical biogeography remain largely unexplored. Here, we present a molecular phylogenetic and biogeographic analyses of Acanthoplectrini to infer the diversification history of this tribe, with emphasis on the Oriental lineage. Both the Oriental and Australian lineages are monophyletic and recovered as sister groups. Ancestral area reconstruction suggests that the ancestor of Acanthoplectrini might have been once widely distributed from Indochina to Australia and then split into the Oriental and Australian lineages during the early-Miocene. Our analyses recovered northeastern Indochina and south China as the ancestral range of the Oriental Acanthoplectrini. During the mid-Miocene to the mid-Pliocene, orographic events such as the rising of mountain ranges (including the Himalayas) and the formation of major islands in southeastern Asia triggered several dispersal and vicariance events in the Oriental Acanthoplectrini, driving their speciation. We revise the classification of the Oriental Acanthoplectrini, establishing the new genus Paralayahima gen. n., which is recovered sister to Layahima Navás. Moreover, we describe four new species of Layahima, Layahima aspoeckorum sp. n., Layahima monba sp. n., Layahima lhoba sp. n. and Layahima xinliae sp. n., and we reinstate two previously synonymized species, Layahima melanocoris (Yang) stat. rev. and comb. n. and Layahima nebulosa Navás stat. rev. [ABSTRACT FROM AUTHOR]

The Cenozoic Indian–Eurasian collision and uplift of the Himalayan‐Tibetan Plateau (HTP) are among the most important geological events in the world. They have affected the diversification of regional biota of many taxonomic groups on and around the HTP. However, the exact timing and model of the collision and uplift events and speciation on and around the HTP are still in debate. The Himalayas group of Scytodes spitting spiders (Araneae: Scytodidae) are distributed at high elevations of the HTP and northern Indochina. Here, we reconstruct a dated molecular phylogeny for pan‐Himalayan Scytodes spiders, including the Himalayas group, with full geographical sampling of the species from the HTP and Indochina. We test a hypothesis to explain that the rich montane biodiversity of the region is uplift‐driven diversification—that orogeny drives rapid in situ speciation of the resident Scytodes lineages. Our findings revealed that the separation of the Himalayas clade from the Myanmar clade took place during the middle Oligocene, reflecting the final collision of India with Eurasia. The deep divergences among three clades (the Himalayas, the Myanmar and the Indochina clades) occurred from the middle Eocene to the middle Oligocene, corresponding to two early uplift events of the HTP. The evolutionary split between the Himalayas + Myanmar and Indochina clades were simultaneous with the rapid lateral extrusion of Indochina by the initial Himalayan uplift around the Eocene. This study highlights the importance of the diversification of dispersal‐limited, high‐elevation invertebrates as independent lines of evidence to reflect key tectonic events in the Himalayan‐Indochina region, supporting the stepwise model for the Indian–Eurasian collision and uplift of HTP. [ABSTRACT FROM AUTHOR]

The Australasian Tektite Event, approximately 0.8 Ma, is the youngest record of a large impact event on Earth. Although it is estimated that it occurred somewhere in Indochina based on the distribution of tektites, the crater has never been located. Here, we report the discovery and occurrence of shocked quartz with planar deformation features (PDFs) in the Quaternary depositional sequence at Huai Om in northeastern Thailand. Measurements of the orientation of lamellae using a universal stage microscope as well as observation using scanning electron microscopy and transmission electron microscopy were conducted to confirm the presence of PDFs. Together with the occurrence of in situ layered tektite fragments, we identify the depositional sequence as the ejecta deposit formed by the Australasian Tektite Event. We further describe the detailed lithostratigraphy of the ejecta deposit, which will allow the tracing of its distribution and lateral changes in its thickness, grain size, and grain composition. Further investigation of the lateral distribution of the ejecta deposit would provide information about the location, magnitude, and target rocks of the Australasian Tektite Event. [ABSTRACT FROM AUTHOR]

The Western Indochina Subregion (Myanmar) represents a freshwater biodiversity hotspot of worldwide significance and houses a plethora of endemic freshwater species, among which are amphibians, fish, and various aquatic invertebrates.The freshwater mussel (Bivalvia: Unionidae) fauna of western Indochina is characterized by high taxonomic richness, with almost all species and several genera being endemic to the subregion. Furthermore, there are a number of species endemic to a single basin or even to a single tributary of a larger river system (the so‐called intra‐basin endemic taxa).Here, the discovery of three new, narrowly endemic freshwater mussel species from northern Myanmar is presented: Radiatula kachinensis sp. nov., Trapezidens mogaungensis sp. nov. (upper Ayeyarwady basin), and Lamellidens chindwinensis sp. nov. (upper Chindwin basin). All the new species are upland river specialists, which are under high human pressure as a result of habitat degradation, deforestation, oil palm expansion, river damming, and biological invasions.A nearly complete lack of data on the life cycles and fish hosts should be considered the most striking gap in recent knowledge of tropical Asian freshwater mussels. Here, available data on 27 species belonging to the genera Radiatula, Trapezidens, and Lamellidens are revised. It is shown that certain fish hosts are known for two species only.Further spread of the alien Chinese pond mussels (Sinanodonta woodiana species complex) in Indochina may be considered one of the significant threats to native freshwater mussel populations. Here, it is shown that the temperate invasive lineage of S. woodiana is established in at least three non‐native populations in the Ayeyarwady and Salween basins. Moreover, the first arrival of the tropical invasive lineage of S. woodiana to Myanmar is announced, although it has been predicted previously. This lineage was found at two sites on the Shan Plateau (Ayeyarwady basin) close to the Chinese border. [ABSTRACT FROM AUTHOR]

This paper continues the publication of newly obtained results from a continuing taxonomic investigation of the genus Aspidistra in Laos and Vietnam. It includes diagnoses of two new species, A. medusa Aver., K. S. Nguyen & Tillich and A. triquetra Aver., Son, Tillich & K. S. Nguyen and amended descriptions of A. khangii Aver. et Tillich and A. locii Arnautov & Bogner previously only known from incomplete material. A lectotype of A. locii is proposed. Color illustrations, new or updated data on morphology, ecology, phenology, tentative relationships, distribution and conservation status are provided for all the mentioned taxa. [ABSTRACT FROM AUTHOR]

The Ora batholith in south‐western Cambodia is situated in the western part of Indochina and east of the Inthanon–Bentong–Raub Palaeo‐Tethys suture and thus bears significant constraints for the equivocal crustal generation of the Palaeo‐Tethys orogenic belt in Mainland South‐east Asia. The Ora batholith consists of monzonitic granite (Group 1), alkali‐feldspar granite (Group 2), and biotite granite (Group 3), and they yield similar Early Jurassic ages of 186.0–199.7 Ma. Group 2 are high‐silica (SiO2 > 75 wt%) rocks with lower TiO2, Al2O3, FeOtot, MgO, CaO, P2O5, Eu, Ba, Sr, P, and Ti contents compared to those of the other two groups. Group 2 and 3 are classified as fractionated‐type granitoids, whereas Group 1 is unfractionated granite as the complementary residual of the fractionated rocks. All groups have positive εHf(t) values from +2.29 to +8.83, suggesting they were cogenetic and derived from partial melting of the lower crust with the addition of asthenospheric mantle material. Integrating with other granitoids in this region, we suggest the Ora granitoids belong to I‐type granitoids. Our petrogenetic and zircon U–Pb age data suggest the Ora granitoids were related to the Early Jurassic post‐collisional magmatism that resulted from crustal thickening and mantle lithospheric delamination due to a denser crustal root than the underlying mantle lithosphere after the Palaeo‐Tethys Ocean closure and collision between the Sibumasu and Indochina terranes. Then the following upwelling of the asthenospheric mantle not only heated and caused partial melting of the lower crust and mantle wedge, but also supplied asthenospheric material to generate the high‐εHf(t) magma. [ABSTRACT FROM AUTHOR]

Indochina is one of the key areas affecting the East Asian summer monsoon and its thermal condition can modulate the prevailing wind and water vapour transport, especially in the early stages of establishment of the summer monsoon. Previous studies emphasized the climatic effect of the seasonal‐averaged soil moisture (SM), but the subseasonal effects of land surface processes over Indochina are not clear yet. This study investigated the subseasonal effect of SM in Indochina on precipitation in southern China (SC) during May and June together with its relevant mechanism based on both statistical analysis and numerical experiments. Results show that increased SM in Indochina in May is closely associated with increased local (Indochina) precipitation and suppressed non‐local (SC) precipitation in June. The positive SM anomaly over Indochina can persist from May to June, cooling the atmosphere and increasing the specific humidity in the lower troposphere. Meanwhile, the potentially unstable lower troposphere and the ascending motion over Indochina result in strengthened upward moisture advection and condensational heating, which are conducive to forming an abnormal cyclonic circulation and increased precipitation over Indochina. To the northeast, an easterly wind anomaly appears in SC, leading to weakened moisture transport and decreased precipitation. When the SM decreases over Indochina, the opposite results are obtained. Moreover, through increasing and decreasing SM in Indochina in May, numerical experiments showed similar results to those of reanalysis data and further indicated that the moist and thermal processes of the SM anomaly over Indochina play distinct roles in affecting the atmosphere and regional precipitation. The moisture process mainly influences local precipitation, whereas the thermal process can change the precipitation non‐locally. This study highlights the significant local and non‐local impacts of SM in Indochina and could contribute to understanding the physical mechanisms of SM effects. [ABSTRACT FROM AUTHOR]

Objective: This study examines the impact of perceptions of young Indian adults about Chinese products in Indian markets upon their purchase behavior, especially after the border conflict in Doklam. Methodology: We have analyzed data collected from a randomly selected sample of 339 educated urban individuals (18–40 years). Binary logistic regression was conducted to estimate the likelihood of buying Chinese products given their level of acceptance among those respondents who are aware of the Indo‐China conflict. Findings: Young Indians mainly focus on quality and price while purchasing a product, and not the country‐of‐origin (COO). Those who took the social media messages to ban Chinese products seriously, concerned about the dominance of Chinese products in the Indian market, and check if the COO is China demonstrate significantly aversive purchase intention towards Chinese products. On the contrary, the odds of purchase decision making getting influenced by Indo‐China conflict is significantly lower for them who have some preference for Chinese products over its Indian substitutes. Conclusions: Feeling of animosity does not result in considerable hostility against the willingness to buy Chinese products, when price, quality, brand awareness, and non‐availability of appropriate Indian substitutes matter more. However, if the sense of animosity is utilized well, Indian manufacturers, especially the MSME sectors, can gain entrepreneurial opportunities and mileage. [ABSTRACT FROM AUTHOR]

We re‐evaluate 357 Jurassic‐Holocene paleomagnetic datasets from Tibet‐Indochina and compare them with present‐day Global Position System velocity field. SE Tibet NW of the East Himalaya Syntaxis (EHS) underwent 20°–30° counterclockwise rotations around 50 Ma, and mostly clockwise rotations after 40 Ma. NE of the EHS, post‐50 Ma clockwise rotation occurred, whereas highly scattered clockwise rotations took place on northern Indochina at 25–15 Ma, after a remagnetization episode. We suggest that the indentation of Greater India NE corner at ∼50 Ma resulted in a wide orogenic reentrant characterized by opposite rotations at orocline limbs. Rotations East of EHS after 40 Ma were likely due to local strike‐slip fault activity. After 30 Ma, the ongoing India collision fragmented Indochina into km‐scale blocks that experienced independent rotations. The present‐day clockwise rotation pattern around the EHS started at 15–10 Ma along with eastward Tibet crustal spreading, and has not produced yet a detectable paleomagnetic rotation. Plain Language Summary: The geodynamic evolution of the Tibetan Plateau and India‐Eurasia collision zone is a matter of vivid debate since the 1970s. In order to assess the deformation of Tibet and north Indochina during the last 50 Ma, we compared 357 paleomagnetic data sets with the present‐day GPS velocity field. Paleomagnetic data suggest that the NE corner of the India plate collided with southern Eurasia at ∼50 Ma, inducing the formation of a continental reentrant with opposite paleomagnetic rotations on curved orogen limbs. Conversely, the post‐30 Ma scattered paleomagnetic rotation pattern of SE Tibet and N Indochina documents a highly fragmented upper crust since middle Cenozoic times. Finally, the Global Position System velocity field shows that at present SE Tibet is characterized by an E‐SE‐ward crust flow and a wide‐scale geodetic clockwise rotation around East Himalayan Syntaxis at a 1–2°/Ma rate. Geologic data indicate that the present‐day kinematics started around 15–10 Ma, and has not yet produced significant paleomagnetic rotations. Key Points: The reliability of 357 Jurassic‐Holocene paleomagnetic datasets from Tibet‐Indochina is addressedThe Cenozoic paleomagnetic rotation pattern is compared with the geodetic rotation rate from Global Position System velocity fieldCollision with NE corner of Greater India at 50 Ma yielded a wide orogenic reentrant and counterclockwise rotations in SE Tibet [ABSTRACT FROM AUTHOR]

The performance of 28 CMIP6 models in simulating the Southeast Asian (SEA) climate is investigated. An evaluation methodology is developed to evaluate spatiotemporal patterns of precipitation, near‐surface temperature, and 850‐hPa wind. Mean annual cycles of temperature and rainfall are assessed separately over Indochina, the Maritime Continent, and the Philippines; and the summer and winter seasons are selected for studying spatial patterns. Within these distinctions, statistics comparing the models to reference data are calculated. The patterns' shape and phase are notably studied, and wind direction differences are assessed specifically over the most major wind flows. We present a scoring procedure allowing us to give each model a unique score reporting on the diverse evaluation aspects, hence establishing a ranking. The process rests on a scoring function growing exponentially with the performance: it favours the models combining good performances according to the largest number of criteria. The assessment highlights EC‐Earth3 and EC‐Earth3‐Veg, which conduct excellent simulations of the regional patterns of rainfall and wind. Their temperature outputs are also reliable, but CNRM‐CM6 ranks first for this variable, while finishing third globally. Local differences are discussed: we emphasize, among other things, the diverse impact of topography on temperature and rainfall, or the frequent deviation of winter winds circulating from the South China Sea to the Java Sea. In addition, a similarity study reveals major difficulties for simulating near‐equatorial annual cycles of temperature and precipitation whereas the summer monsoon spatial rainfall patterns bring out the largest discrepancies. In any event, the top models pointed out by our ranking constitute a high‐performance subset that further climate modelling experiments in SEA can rely on. [ABSTRACT FROM AUTHOR]

The Gejiu alkaline complex (GAC) within the western part of the Youjiang Basin provides a window to investigate the evolution in the junction of Cathaysia, Yangtze and Indochina blocks. Here, we investigate the GAC in terms of their petrology, zircon U–Pb geochronology, whole‐rock geochemistry, and Sr–Nd isotopic data to gain insights into the origin and evolution of the alkaline magma. The GAC is lithologically composed of alkali syenites and feldspathoid syenites, in which some were altered into sericite syenites. Zircon U–Pb dating of the alkali syenites yielded an age of 85.03 ± 0.47 Ma, which is slightly older than the feldspathoid syenites. The alkali syenites and feldspathoid syenites are silica‐saturated and silica‐undersaturated, respectively, and are characterized by high alkalinity with K2O + Na2O of 11.55–17.08 wt% and Al2O3 of 18.57–22.49 wt%, low MgO of 0.11–1.39 wt%, weakly negative Eu anomalies, enrichments of LILEs such as Th and U, HFSEs like Zr and Hf but depletion of Ba, Sr, Nb, Ta, P, Ti, strongly fractionated LREEs to HREEs. Their uniform Sr–Nd isotope composition with initial 87Sr/86Sr = 0.708802–0.710571 and εNd(t) = −7.1 to −6.6 indicates that they were products of a homologous magma. They crystallized at c. 810–956°C and have a relatively high magmatic oxygen fugacity. Our geochemical and isotopic data proved that the GAC magma was derived from the low‐degree partial melting (<10%) of a phlogopite‐bearing‐enriched mantle that was metasomatized by subducting sediments and originated possibly from the spinel and garnet transition zone at a depth of 60–80 km and a pressure of about 1.8–2.4 Gpa. The primary magma experienced protracted two‐stage crystal fractionation of clinopyroxene+amphibole and biotite+K‐feldspar, forming alkali syenites and feldspathoid syenites. Crustal contamination plays a negligible role in their formation. Considering previous tectonic studies, it was therefore proposed that the GAC formed in an extensional tectonic setting related to the Neo‐Tethyan tectonic regions during the Late Cretaceous. [ABSTRACT FROM AUTHOR]

Future changes in the frequency and destructiveness of landfalling tropical cyclones (TCs) over East Asia were investigated by analyzing the simulations of two high‐resolution (20–25‐km) atmospheric general circulation models forced by sea surface temperature (SST) in the present period (1979–2003) and under future warming conditions (2075–2099) of the RCP8.5 scenario. The present‐day simulations capture well the genesis count, tracks, and intensity associated with TCs striking the coastal areas of Taiwan‐East China (TWCN), the South China Sea‐Indochina (SCS) and the vicinity of Japan (JP). The frequency of landfalling TCs over TWCN, SCS, and JP is projected to nearly half by the end of the 21st century. However, these landfalling TCs induce enhanced destructive threats of stronger winds and heavier precipitation under the future warmer climate. Through attribution analysis we found the reduced frequency of landfalling TCs to be mainly caused by a decline in TC genesis count (rather than TC track changes), while the increased intensity of landfalling TCs is linked with changes in the TC intensification rate (as opposed to duration changes). Diagnoses of the genesis potential index and eddy energetics further suggest that the mid‐tropospheric drying and weakened synoptic‐scale eddy activity resulting from anticyclonic and downward circulations over the main TC genesis region create an unfavorable environment for TC genesis. In contrast, warmer SST, reduced vertical wind shear and enhanced efficiency of eddy kinetic energy generations appear over the regions before TC landfall, resulting in a more rapid intensification of TCs that later approach the coastal areas. Key Points: The frequency of landfalling tropical cyclones (TCs) over East Asia is projected to nearly half by the end of 21st centuryThe destructiveness of landfalling TCs show a tendency to strengthen in the future, with stronger winds and heavier precipitationThe reduced frequency is attributed to less TC genesis, while the enhanced intensity is attributed to a higher intensification rate [ABSTRACT FROM AUTHOR]

Located at the end of the northern Manila Trench, the Hengchun Peninsula is the latest exposed part of Taiwan Island, and preserves a complete sequence of accretionary deep‐sea turbidite sandstones. Combined with extensive field observations, a 'source‐to‐sink' approach was employed to systematically analyze the formation and evolutionary process of the accretionary prism turbidites on the Hengchun Peninsula. Lying at the base of the Hengchun turbidites are abundant mafic normal oceanic crust gravels with a certain degree of roundness. The gravels with U‐Pb ages ranging from 25.4 to 23.6 Ma are underlain by hundreds‐of‐meters thickness of younger deep‐sea sandstone turbidites with interbedded gravels. This indicates that large amounts of terrigenous materials from both the 'Kontum‐Ying‐Qiong' River of Indochina and the Pearl River of South China were transported into the deep‐water areas of the northern South China Sea during the late Miocene and further eastward in the form of turbidity currents. The turbidity flow drastically eroded and snatched mafic materials from the normal South China Sea oceanic crust along the way, and subsequently unloaded large bodies of basic gravel‐bearing sandstones to form turbidites near the northern Manila Trench. With the Philippine Sea Plate drifting clockwise to the northwest, these turbidite successions eventually migrated and, since the Middle Pleistocene, were exposed as an accretionary prism on the Hengchun Peninsula. [ABSTRACT FROM AUTHOR]

The offset of geological bodies provides robust evidence of displacement along a fault or ductile shear zone. The amount of displacement along the Xuelongshan–Diancangshan–Ailaoshan structural system, southeastern Tibetan Plateau, is uncertain because of the lack of offset geological markers. This NNW–SSE‐trending system is developed in three isolated metamorphic complexes and interjacent nonmetamorphosed rocks. They are expected to record similar post‐Eocene strain, although their structural patterns should be distinct. Geological mapping in the area between the Xuelongshan and Diancangshan metamorphic complexes has revealed a small Eocene basin, the Madeng Basin, located to the west of the structural system. The sedimentary and volcanic successions of the Madeng Basin are comparable to those of the Jianchuan Basin, which is located to the east of the structural system. Zircon U–Pb geochronological and bulk geochemical data demonstrate that the volcanic rocks of both basins formed during 37–34 Ma and share the same geochemical features. These data suggest that the Madeng and Jianchuan basins previously constituted a single basin, with the distribution of high‐K volcanic rocks in the basins defining an ENE–WSW‐trending volcanic belt that shows a limited dextral offset of ≤20 km across the Xuelongshan–Diancangshan–Ailaoshan structural system. Therefore, the northern segment of the structural system records no evidence of large‐scale lateral movement/displacement. The results suggest that the Indochina block, which is bounded by the Xuelongshan–Diancangshan–Ailaoshan structural system to the east and the Sagaing Fault to the west, has not extruded southward as a whole but rather has been deformed by pervasive crustal shortening. [ABSTRACT FROM AUTHOR]

Results from the multiple‐realization, single‐model ensemble called "d4PDF" were used to generate hydroclimate indices for present and future climates over the Indochina region. The model performed reasonably well in capturing the reference precipitation characteristics of the present climate (1951–2010), in particular the seasonal pattern (e.g., JJA and SON) and intensity‐based indices such as SDII, R95p, Rx1D, and Rx3D. Under the +4 K future simulation conditions for 2051–2110, comprising six prescribed sea‐surface temperature scenarios, substantial and statistically significant increases in precipitation frequency (R10 and R20) and intensity (SDII, Rx1D, and Rx3D) were projected over the Indochinese Peninsula with a high degree of consistency. However, there were greater uncertainties in the changes significance of mean precipitation either during early dry‐season (DJF) or late monsoon (SON) indices demonstrated by results of the parametric U test in some river catchments, such as the Chao Phraya, Red River, central Mekong, lower Irrawaddy, and Salween Basins, where the projection consistencies in a positive change direction were less than 50%. Comparison of basin‐wide empirical probability distributions of precipitation indices pointed to a robust increase in the frequency of the occurrence of heavy precipitation in intensity indices (e.g., Rx1D, Rx3D, and SDII). The relationship between d4PDF precipitation and total runoff generation outputs from the land surface component was investigated. The results show a high degree of temporal correspondence across the region under the present climate in several seasonal and intensity indices, except during the dry period (DJF and MAM). Finally, we found that εP(P, R) of the annual and seasonal climatological indices of the future climate were always positive and larger than unity, with a median εP(P, R) of 1.28–2.04. The results strongly reaffirm the role of rainfall as the main driver of runoff changes due to its faster response relative to change in precipitation at the Indochina Region. [ABSTRACT FROM AUTHOR]

Paleomagnetic studies on the syncollisional magmatic eruptions provide a direct way to understand when and where the Paleo‐Tethys closed. We report a well‐dated paleomagnetic pole from the southern Lancangjiang volcanic belt in western Yunnan of China. Stable Characteristic Remanent Magnetizations (ChRMs) were isolated from 21 sites at high temperatures following step‐wise thermal demagnetization. The data pass fold, reversal, and conglomerate tests and are interpreted to be primary thermal remanent magnetizations. The new paleomagnetic pole (46.1°N/176.2°E, K=44.9, A95=4.8°, N=21) yields a paleolatitude of 26.0 ± 4.8°N at the reference site (23.0°N/100.4°E) in the southern Lancangjiang area. This direct paleo‐latitudinal constraint on the Paleo‐Tethys suture zone in western Yunnan indicates that the north branch of the Paleo‐Tethys Ocean closed no later than the Carnian Age of Late Triassic, and confirms a geographic linkage between the North Qiangtang and Indochina Blocks at least during the Early Permian to Late Triassic. Plain Language Summary: The Asian continent is formed by the amalgamation of continental blocks such as the Tarim, North China, South China, Indochina, and Qiangtang. However, questions remained to answer: When did the ocean between them close? How did they drift from the south hemisphere to the north? In this study, we present a paleomagnetic constraint on the Paleo‐Tethys suture zone to quantify when and where the Paleo‐Tethys Ocean closed. The Paleo‐Tethys Ocean closed no later than the early Late Triassic at ~26°N. The Indochina and North Qiangtang drifted together from the south hemisphere to the north during the Permian‐Triassic. Key Points: The southern Lancangjiang volcanic belt formed at a paleolatitude of ~26ºN during the Carnian Stage of the Late TriassicThe north branch of the Paleo‐Tethys closed no later than the Carnian Stage of the Late TriassicA Permo‐Triassic geographic linkage between Indochina and N‐Qiangtang is confirmed [ABSTRACT FROM AUTHOR]

Aim: Current species distributions are shaped by present and past biotic and abiotic factors. Here, we assessed whether abiotic factors (habitat availability) in combination with past connectivity and a biotic factor (body mass) can explain the unique distribution pattern of Southeast Asian mammals, which are separated by the enigmatic biogeographic transition zone, the Isthmus of Kra (IoK), for which no strong geophysical barrier exists. Location: Southeast Asia. Taxon: Mammals. Methods: We projected habitat suitability for 125 mammal species using climate data for the present period and for two historic periods: mid‐Holocene (6 ka) and last glacial maximum (LGM 21 ka). Next, we employed a phylogenetic linear model to assess how present species distributions were affected by the suitability of areas in these different periods, habitat connectivity during LGM and species body mass. Results: Our results show that cooler climate during LGM provided suitable habitat south of IoK for species presently distributed north of IoK (in mainland Indochina). However, the potentially suitable habitat for these Indochinese species did not stretch very far southwards onto the exposed Sunda Shelf. Instead, we found that the emerged landmasses connecting Borneo and Sumatra provided suitable habitat for forest dependent Sundaic species. We show that for species whose current distribution ranges are mainly located in Indochina, the area of the distribution range that is located south of IoK is explained by the suitability of habitat in the past and present in combination with the species body mass. Main conclusions: We demonstrate that a strong geophysical barrier may not be necessary for maintaining a biogeographic transition zone for mammals, but that instead a combination of abiotic and biotic factors may suffice. [ABSTRACT FROM AUTHOR]

Abstract: We propose a framework that enables the evaluation of a large number of climate models by numerous performance metrics, which can be customized toward a specific impact assessment perspective under climate change (e.g., agriculture, flood control, or else). The customization is performed by weighting the performance metrics. Three criteria are applied to combine a set of diagnostics for creating a single performance index, namely, summation of rank (SR), Euclidean distance of the cluster analysis (CA), and that of Empirical Orthogonal Function analysis (EOF). These indices are then used to objectively select optimal ensemble subsets by applying a culling method. The model evaluation and multimodel ensemble selection in the Indochina Region as a study area are performed on precipitation for two cases: a nonweighted case applying equal weights for all 36 metrics, and a weighted case focusing on the evaluation for agricultural drought monitoring, as an example, with and without model independence and skill weights. We demonstrate that the optimal ensemble subsets of this framework improve significantly the distribution of monthly precipitation data compared to those of the best single model or the full model ensemble during the historical period. The optimal ensemble subsets of CA and EOF criteria are improved more than those of the SR criterion. The performance of the optimal ensemble subsets is also confirmed in the future projection for the RCP8.5 scenario by implementing model‐as‐truth experiments. A simple and user‐friendly decision graph of all model members for the ensemble selection is developed, and its usefulness is demonstrated. [ABSTRACT FROM AUTHOR]

Indochina is a biodiversity hot spot and harbors a high number of endemic species, most of which are poorly studied. This study explores the genetic structure and reproductive system of the threatened endemic timber species Dalbergia cochinchinensis and Dalbergia oliveri using microsatellite data from populations across Indochina and relates it to landscape characteristics and life-history traits. We found that the major water bodies in the region, Mekong and Tonle Sap, represented barriers to gene flow and that higher levels of genetic diversity were found in populations in the center of the distribution area, particularly in Cambodia. We suggest that this pattern is ancient, reflecting the demographic history of the species and possible location of refugia during earlier time periods with limited forest cover, which was supported by signs of old genetic bottlenecks. The D. oliveri populations had generally high levels of genetic diversity (mean He = 0.73), but also strong genetic differentiation among populations (global GST = 0.13), while D. cochinchinensis had a moderate level of genetic diversity (mean He = 0.55), and an even stronger level of differentiation (global GST = 0.25). These differences in genetic structure can be accounted for by a higher level of gene flow in D. oliveri due to a higher dispersal capacity, but also by the broader distribution area for D. oliveri, and the pioneer characteristics of D. cochinchinensis. This study represents the first detailed analysis of landscape genetics for tree species in Indochina, and the found patterns might be common for other species with similar ecology. [ABSTRACT FROM AUTHOR]

The Song Ma region, which is located in the northwestern Vietnam represents the zone of amalgamation between Indochina and South China blocks. Numerous scattered ultramafic rocks occur in this region in association with Early to Middle Palaeozoic greenschists and paragneisses, and all these rocks were subjected to hydrous metamorphism and deformation. Here, we present new field data, mineral chemistry and geochemistry from a suite of hydrated peridotites within the Song Ma region and discuss the tectonic significances of the region. We also combine the available data within the Song Ma region and Indochina-South China blocks to discuss the tectonic evolution of the subduction zone. Based on the results, we suggest that the peridotites from the Song Ma are mantle residues that suffered a high degree of partial melting in a forearc tectonic setting. The present data together with the available data within the Song Ma region and the Indochina and South China blocks clearly represent a southward directed Middle Palaeozoic subduction system. The Middle Palaeozoic subduction and accretion events mark the evolutionary history along an active convergent margin between the Indochina and South China blocks, possibly related to the amalgamation of the Pangaea supercontinent. Copyright © 2015 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

The first finding of low-temperature eclogites from the Indochina region is reported. The eclogites occur along the Song Ma Suture zone in northern Vietnam, which is widely regarded as the boundary between the South China and Indochina cratons. The major lithology of the area is pelitic schist that contains garnet and phengite with or without biotite, chloritoid, staurolite and kyanite, and which encloses blocks and lenses of eclogite and amphibolite. The eclogites commonly consist of garnet, omphacite, phengite, rutile, quartz and/or epidote with secondary barroisite. Omphacite is commonly surrounded by a symplectite of Na-poor omphacite and Na-rich plagioclase. In highly retrograded domains, diopside + tremolite + plagioclase symplectites replace the primary phases. Estimated peak-pressure metamorphic conditions based on isochemical phase diagrams for the eclogites are 2.1–2.2 GPa and 600–620 °C, even though thermobarometric results yield higher pressure and temperature conditions (2.6–2.8 GPa and 620–680 °C). The eclogites underwent a clockwise P–T trajectory with a post-peak-pressure increase of temperature to a maximum of >750 °C at 1.7 GPa and a subsequent cooling during decompression to 650 °C and 1.3 GPa, which was followed by additional cooling before close-to-isothermal decompression to ∼530 °C at 0.5 GPa. The surrounding pelitic schist (garnet–chloritoid–phengite) records similar metamorphic conditions (580–600 °C at 1.9–2.3 GPa) and a monazite chemical age of 243 ± 4 Ma. A few monazite inclusions within garnet and the cores of some zoned monazite in garnet–phengite schist record an older thermal event (424 ± 15 Ma). The present results indicate that the Indochina craton was deeply (>70 km) subducted beneath the South China craton in the Triassic. The Silurian cores of monazite grains may relate to an older non-collisional event in the Indochina craton. [ABSTRACT FROM AUTHOR]

Aim Our understanding of the geographic patterns of gene flow between populations of birds in the Indo-Malayan faunal region is surprisingly poor compared with that in other parts of the world. A thorough knowledge of general patterns of phylogeographic structure is, however, of utmost importance for conservation purposes. Species with poor dispersal capabilities could serve as indicators of endemism and genetic isolation in the Indochinese subregion. From their morphology (tiny size, short tail, short and rounded wings), piculets of the genus Sasia are inferred to have poor dispersal capabilities, and thus form a suitable focal species. This study analysed the pattern of genetic variation within the White-browed Piculet ( Sasia ochracea). Location Southeast Asia, north of the Isthmus of Kra. Methods We sampled 43 individuals throughout the breeding range of S. ochracea. DNA was extracted both from fresh tissues ( n = 15) and from toe pads from ancient museum skins ( n = 28). We amplified a 801-bp fragment of the mitochondrial ND2 gene to reconstruct the phylogeographic history of the White-browed Piculet. The sequence data were analysed using Bayesian inference, statistical parsimony, and population genetics methods (analysis of molecular variance, mismatch distributions). We estimated the amount of ongoing gene flow between populations using the coalescent-based method implemented in Mdiv. Results The analysis of molecular variance indicated that the current taxonomy does not adequately reflect the amount of genetic variation within S. ochracea, as the great majority of genetic variation was nested within the nominal subspecies, which is distributed from Nepal to southern Vietnam. Bayesian inference analyses and haplotype networks suggested the occurrence of five main lineages that are strongly correlated with geography. Our coalescent-based analyses indicated a very limited amount of ongoing gene flow between these five lineages. Our dating analyses suggested that the genetic structuring probably occurred during the last 400,000 years. Main conclusions Our analyses revealed that S. ochracea is composed of at least five lineages: south Vietnam (South Annam and ‘Cochinchina’), India and Nepal, Myanmar and India, the remainder of Indochina, and probably southern Myanmar (Tenasserim). We strongly recommend that studies aiming to understand the phylogeographic structure within Indo-Malayan species sample these areas. [ABSTRACT FROM AUTHOR]

ABSTRACT 1. The lack of a globally accepted list of English-language names for mammal species leads to various problems stemming from the reduced ability to communicate unambiguously. This impacts directly on their conservation. We use the larger mammals of Indochina to exemplify the use of an explicit set of principles designed to provide each species with a unique and non-misleading (or at least minimally so) English name. 2. For most species, a suitable name is already in use, sometimes generally so. For species for which multiple names are in use, standardization would consist of adopting the most suitable name. Only for a very few species are all extant names so unsuitable that a neologism should be coined. One species, Panthera pardus , presents potentially insoluble problems. 3. Name standardization among the world's birds has generated some controversy, but this has not led to abandonment of the process. Much can be learned by those developing a similar process for mammals, through studying the bird-naming process. Progress can be advanced by detractors indicating whether they oppose standardization per se , the principles used or the names resulting from application of the principles. Also, proponents of standardization should always emphasize that the purpose of the process is to produce a list available for those who want to use it, not to produce a binding selection that must be used in all circumstances. [ABSTRACT FROM AUTHOR]

Presents the schedule of religious events organized by the catholic organizations in association with the World Council of Churches (WCC) as of January 1, 1980. Plans of the WCC Executive Committee for the eighties; Development of religious liberty; Assistance to refugees from Indochina; Objectives of the Zimbabwe constitutional conference; Consultation on racism by the WCC; Schedules of the next WCC meetings.

The article seeks to present some works by British and French writers from the 1960s which make a significant contribution to the knowledge and understanding of the events which have occurred in Indochina since the end of the Second World War. It discusses literature about the first Indochina War between the French and the Viet Minh, and the second Indochina War in Vietnam. A comparison of the work of French military theorist Gabriel Bonnet about the nature of the revolutionary war waged in Vietnam and a similar work by British theorist Robert Thompson is included.

The article discusses the measures to reduce the number of undocumented migrants in Hong Kong, China. It mentions that Hong Kong government, with the help of several governments and non-governmental organizations, has exercised efforts to fights against illegal migration. It states that illegal migrants in Hong Kong were classified into three categories such as illegal migrants from Mainland China, refugees from Indochina, and illegal migrants from other regions of the world. It says that 200,000 people were added to the population of Hong Kong in 1962, which was allegedly due to legal and illegal migration from Mainland.

Sensitivity of afternoon precipitation to before‐noon evaporative fraction (EF) in eastern Asia is investigated by applying two physically based, objective metrics (i.e., triggering feedback strength [TFS] and amplification feedback strength [AFS]) with the ERA‐Interim datasets. Over the northern Indian Peninsula, the Mongolian Plateau and Myanmar, increased before‐noon EF will trigger afternoon precipitation most likely. On the contrary, over south China and Indo‐China peninsula, decreased EF may enhance the occurrence probability of afternoon rainfall. Based on the normalized values of two metrics, the triggering effect of EF is much larger than its amplification effect on afternoon precipitation, and the amplification effect is very small. (a) TFS (units of probability of afternoon rain) and (b) AFS (units of millimeters of afternoon rain) in summer. Shading indicates that the mean of the 50 samples is significantly different from zero based on the two‐sided t test at the 95% significance level. [ABSTRACT FROM AUTHOR]

The collision between India and Eurasia in the mid‐Palaeogene facilitated terrestrial floristic exchange. However, due to the complexity of this geological event and scarcity of fossil record, the plant migration patterns between the two plates are still highly debated. In this study, we focus on the Oligocene floristic exchange between India and Pan‐Indochina mainly based on a carpological study of Annonaceae, an emblematic family unique in its pantropical distribution and frugivore‐based dispersal strategy. A new seed species, Anonaspermum orientalis sp. nov., is described from the upper Oligocene Yongning Formation of Guangxi, southern China. The species represents the earliest known occurrence of this family in Pan‐Indochina. The specimens are characterized by ovate–elliptic seed shape, thicker seed testa, two‐lobed organization, lamelliform rumination and an obvious cone‐like plug. The palaeobiogeographical reconstruction of Annonaceae indicates that the most parsimonious dispersal scenario for the annonaceous taxon from the late Oligocene of China is the Out‐of‐India route, in parallel with other plant genera inferred to have migrated between India and Pan‐Indochina during that period. [ABSTRACT FROM AUTHOR]