Northeastern Asia Research Articles

Prediction of summer extreme hot days in China using the SINTEX‐F2

AbstractAccurate prediction of extreme weather and climate is crucial for their devastating impacts on our society and environment. Here, predictability of frequency of summer (June–August) extreme hot days (SEHDs) in China has been assessed in the SINTEX‐F2 seasonal forecast system during the period of 1983–2015. The hindcast had 12 ensemble members and was initialized on the first day of March, April and May, respectively. Results show that overall, the SINTEX‐F2 predicts more regions with good prediction skills at shorter lead time due to its better capture of the linear trends. Whereas, in Southwest China and eastern Tibetan Plateau, the prediction skills are consistently increased at shorter lead time even without the impacts of linear trends; the correlation coefficients between the region‐mean anomalies in the observed and predicted SEHD frequencies are 0.74, 0.68 and 0.61 at 1–3 month lead, respectively, and they remain as high as 0.56, 0.49 and 0.40 when the linear trends are removed. This is because the SINTEX‐F2 can reproduce the observed influences of Indian Ocean Basin Mode (IOBM) on the SEHD frequency. The warm IOBM can cause anomalous ascending and strong divergence in the upper troposphere over the tropical Indian Ocean and Indian subcontinent. The strong divergence causes direct convergence and descending over Southwestern China and eastern Tibetan Plateau. It also causes substantial descending over the western North Pacific that can introduce anomalous cyclonic circulation over northeastern Asia via the Pacific‐Japan or East‐Asia pattern. The latter serves as a source of wave energies, excites the Rossby waves meandering westward in the mid‐latitude, and enhances the anticyclonic circulation anomalies over Southwestern China and eastern Tibetan Plateau.

Estimates of temporal-spatial variability of wildfire danger across the Pan-Arctic and extra-tropics

Satellite-based hot-spot analysis for the Pan-Arctic, shows that Asia experiences a greater number of fires compared to North America and Europe. While hot spots are prevalent through the year in Asia, Europe (North America) exhibits marked annual (semi-annual) variability. The Potential Fire Danger index (PFIv2) demonstrates increased fire incidence vulnerability across the Arctic and extra-tropics. Though not significant in northwestern North America and eastern Asia, significant-positive trends across the mid-latitudes of Eurasia and Siberia are clear. PFIv2 accurately matches the regional distribution of observed fires, while the worldwide used Fire Weather Index does not. Fire danger has evolved as distributions of short-interval precipitation events and background vegetation characteristics change. In conjunction with increased population and expanded infrastructure, frequent extreme events may increase pressure for new settlements that lead to greater fire exposure across the Pan-Arctic. Thus, PFIv2 may be useful for decision planners and danger managers to anticipate and minimize the adverse effects of indiscriminate fire use.

The function of root mat fungal communities: Changes in response to pH and phosphorus addition

Societal Impact StatementAcid deposition affects forests in eastern North America, Europe, and eastern Asia, and reduces nutrient availability for forest trees. Reduced nutrient availability can reduce tree growth and forest productivity. Our research suggests that trees may rely on fungi, including mycorrhizal fungi, that colonize root mats near the soil surface for nutrient acquisition in forests subjected to acid‐induced nutrient limitation. These fungi may increase acquisition of nutrients from organic matter. Forest management practices that limit surface soil disturbance and damage to root mats, especially during timber harvesting activities, may be important for conserving forest productivity in regions subjected to acid deposition.Summary Many temperate forest soils are affected by a legacy of acid deposition, which can mobilize soil aluminum and reduce phosphorus (P) availability. These chemical changes are mostly manifest in mineral soil. However, many temperate trees have extensive shallow roots, or root mats, which are found on the surface of mineral soil. These root mats are in contact with the O horizon where substantial organic nutrients exist. But the role of root mats in accessing nutrients in nutrient limited, acidic soil is not well understood. We examined root mat fungal communities and their function using an existing 6‐year ecosystem‐level pH and P manipulation experiment, which artificially increased pH by more than 1.5 units and increased available P threefold. Dominant fungal taxa on roots were identified using Sanger sequencing and broad community changes were assessed using DNA fragment analysis. Nutrient acquisition within root mats was assessed by measuring the extracellular enzyme activity in rhizosphere soil. Fungal community structure changed with soil pH, while P availability altered extracellular enzyme production of phosphomonoesterase, β‐1,4‐glucosidase, and leucine aminopeptidase. Quercus–Fagus root mats contained ectomycorrhizal fungi and Acer roots contained both ectomycorrhizal and arbuscular mycorrhizal fungi. Interestingly, both Acer and Quercus–Fagus root mats contained ericoid mycorrhizal fungi, which were less abundant at higher pH. Our results suggest an important role of root mats in nutrient acquisition from organic sources in temperate forests. These root mats could assist plants in overcoming the legacy of acid deposition in temperate forests.

Petrogenesis of the Cenozoic volcanic rocks in Baekdu volcano in northeastern Asia and the expected depth of the magma chamber based on geochemistry, mineral chemistry, and Sr-Nd-Pb isotope chemistry

Baekdu volcano is a Cenozoic composite volcano in northeastern Asia that consists of a basaltic plateau, a basaltic shield, and a trachytic to comenditic stratovolcano. In this study, the petrogenesis and tectonic setting of Baekdu volcano are studied based on the whole-rock geochemistry and Sr-Nd-Pb isotope compositions of the Baekdu volcanic rocks. The K–Ar age and mineral chemistry are also investigated to estimate the evolution of the magma chamber depth beneath Baekdu volcano. The Toudao and Baishan basalts formed ca. 2.5 Ma and 1.1 Ma and erupted from magma chambers located at depths of 11.5 ± 2.2 km and 24.9 ± 3.8 km, respectively. The Xiaobaishan and Middle trachytes and the comendites formed during the Pleistocene from magma chambers located at depths of 2.9 ± 0.2 km, 5.4 ± 0.45 km, and 4.4 ± 0.3 km, respectively. These data suggest that the trachytes and comendites erupted from magma chambers located at depths of approximately 3–5 km. The Baishan basalts have geochemical characteristics comparable with those of ocean island basalt (OIB), whereas the Toudao basalts show enriched mid-ocean ridge basalt (E-MORB) or OIB characteristics. The trends of several components, such as the CaO/Al2O3 ratio and the TiO2 and Sc concentrations, are different between older basalts (>2 Ma, including the Toudao basalts) and younger basalts (<1.5 Ma, including the Baishan basalts), indicating that the magma-forming process changed ca. 2–1.5 Ma. The enrichment in Th/Yb ratios in the Toudao basalts indicates that they experienced crustal contamination. Trachytes and comendites are considered to be products of the fractional crystallization of the Baishan basalt based on the similar geochemical trends of the two rocks. Crustal assimilation (up to 20%) also occurred with fractional crystallization (more than 70%) during the formation of peralkaline silicic volcanic rocks. All volcanic rocks in Baekdu volcano have Sr-Nd-Pb isotope compositions comparable with the enriched mantle (EM1)-like signature. This EM1-like signature may have originated from the contamination of asthenospheric mantle with Paleoproterozoic lithosphere that sank into the asthenospheric mantle due to delamination caused by regional extensional events in northeastern Asia between the Cretaceous and the Cenozoic. The characteristics of trace element compositions indicate a within-plate tectonic setting for Baekdu volcano. These data imply that Baekdu volcano origin may have been related to a plume of EM1-type upper mantle under the North China Craton.

Undaria pinnatifida exudates trigger shifts in seawater chemistry and microbial communities from Atlantic Patagonian coasts

The invasive kelp Undaria pinnatifida has spread from northeastern Asia to temperate coastal environments worldwide, with profound effects on colonized ecosystems. In this work, we analyzed the effect of exudates from U. pinnatifida on the chemical and microbial properties of seawater from a semi-enclosed gulf from Atlantic Patagonia. Exudates of U. pinnatifida, consisting mainly of carbohydrates, were released at a rate of 1.6 ± 0.8 mg C g−1 algae day−1, affecting the quality and optical properties of seawater in experimental incubations. Parallel factor analysis based on excitation-emission matrices collected from exudates revealed the presence of two humic-like and one non-humic fluorescent components. Exudate release stimulated microbial growth and polysaccharide degrading activity in seawater. After a 7-day incubation of fresh seawater with the exudates, changes in microbial community structure were analyzed by large-scale 16S rRNA gene amplicon sequencing. Copiotrophic and fermentative genera such as Spirochaeta (Spirochaetes) and Propionigenium (Fusobacteria) increased in the incubations with algal exudates. Genomic potential prediction revealed that the selected bacterial community could have higher ribosome content—an indicator of the potential for reaching higher metabolic rates—and genes for the degradation of complex organic compounds such as polysaccharides and other carbohydrates present in the exudates. Nutrient addition triggered the emergence of other microbial populations with different ecophysiological niches: unclassified Flavobacteriales, unclassified bacteria related to the recently described Phylum Kiritimatiellaeota, as well as potential pathogens such as Vibrio (Gammaproteobacteria) and Arcobacter (Epsilonproteobacteria), suggesting potential synergistic effects between invasive macroalgae and human activities.

Paleoaltingia gen. nov., a new genus of Altingiaceae from the Late Cretaceous of New Jersey

Altingiaceae is a small family with a bimodal Northern Hemisphere distribution in eastern North America and eastern Asia, and a rich Cenozoic fossil record. The charcoalified fossil infructescence Paleoaltingia gen. nov. from Turonian (Late Cretaceous) deposits of New Jersey, provides new evidence of early Altingiaceae reproductive structures and has biogeographical implications in understanding modern distribution. Fossils were prepared using standard methods for obtaining and processing mesofossils. The fossils were examined with light microscopy, and scanning electron microscopy for observing structural and anatomical details. Phylogenetic analyses were performed using a combined matrix of molecular and morphological data. Based on morphological features of the fossil and the phylogenetic analyses, the new genus, Paleoaltingia, with two species (Paleoaltingia ovum-dinosauri and P. polyodonta) is erected. The phylogenetic position of Paleoaltingia confirms affinities with living Altingiaceae. The combination of characters-simple capitate infructescence, syncarpous bicarpellate, and bilocular ovary, unique sterile phyllome structures-indicates that the fossil taxa have close affinities to modern Altingiaceae. The unique characters of the phyllomes provide new information on the floral diversity of Altingiaceae. The emergence of Paleoaltingia in Late Cretaceous sediments of Northeastern North America represents the earliest fossil record of Altingiaceae and provides new insights into its biogeography.

In Situ Measurement of Sound Attenuation by Fish Schools (Japanese Horse Mackerel, Trachurus japonicus) at Mid-Frequency Bands

Acoustic waves are attenuated by fish schools as they propagate through the ocean. The attenuation by fish schools is not currently considered in fishery acoustics and sonar applications, especially at mid-frequency bands. In this study, fish school attenuation experiments were conducted with a number of individual fish in situ in a net cage at mid-frequency bands (3–7 kHz). The target fish species was the Japanese horse mackerel (Trachurus japonicus), which typically forms fish schools in the coastal ocean of northeastern Asia. The attenuated acoustic waves were measured for the cases of non-net, only net (0), 100, 200, 300, 400, and 500 individual horse mackerels in the net cage. Results showed that the acoustic signal attenuation increased with the number of horse mackerels. The mean and maximum attenuation coefficients were approximately 6.0–15.4 dB/m and 6.5–21.8 dB/m for all frequencies, respectively. The measured attenuation coefficients were compared with the ones from previous studies to propose new regression models with normalized extinction cross-sections of weight and length of fish. This study confirmed that the fish school attenuation could not be ignored and compensated at mid-frequencies in the ocean. These results would be useful for fishery acoustics, especially in the development of scientific echo-sounder, and naval applications of sonar operations and analysis.

Multiple genetic marker analysis challenges the introduction history of Ulva australis (Ulvales, Chlorophyta) on French coasts

ABSTRACT The green seaweeds Ulva australis and U. pertusa were described from southern Australia and Japan, respectively. They are conspecific and U. australis, the currently accepted taxon, is native to temperate marine waters in north-eastern Asia, and known to be introduced overseas into Australasia, the Americas and Europe. Although the genetics of U. australis have been investigated elsewhere, along French coasts the origins and history of the introduction of this species need to be clarified. We used mitochondrial, plastid and nuclear markers to differentiate introduced populations of U. australis along the French Atlantic coasts. The plastid tufA gene used as a barcoding marker revealed a well-defined species with a higher haplotype diversity in native vs. introduced areas. The ITS2 region (nuclear) and rbcL (plastid) were used to compare French specimens with the lectotype of U. australis. Putative geographic origins of the genetically determined U. australis were examined using genetic markers with better resolution, the plastid atpI-H combined with the mitochondrial trnA-N. Origin(s) and introduction history of French specimens were inferred from the comparison between their haplotypes and those previously described in native and non-native temperate areas worldwide. Our results indicate that the presence of U. australis along the French Atlantic and Mediterranean coasts is the result of multiple introductions and independent pathways, and suggest that historical oyster transfers from Japan and British Columbia can only partially explain the observed patterns in genetic markers. Alternative hypotheses for the timing and pathways of introductions are proposed in the light of the historic background of maritime transport networks and trade between north-eastern Asia and Europe.

The tectonic evolution of the Gogunsan Islands in the southwestern margin of the Gyeonggi Massif and its implication for the Neoproterozoic tectonic evolution relating to the Rodinia in the Northeast Asia

The Neoproterozoic rocks recognized in several locations on the Korean Peninsula provide important insight into the geological correlation between the Korean Peninsula and China and for understanding the tectonic processes occurring in northeastern Asia. The Gogunsan Islands, located on the southwestern margin of the Gyeonggi Massif of the Korean Peninsula, consist of Neoproterozoic igneous and sedimentary rocks. The sedimentary rocks in the Gogunsan Islands are divided into the Maldo and Bangchukdo Formations. The Maldo Formation was deposited sometime between 950 and 894 Ma and intruded by or tectonically contacted Neoproterozoic igneous rocks 930–894 Ma in an arc tectonic setting. The εHf(t) values of metabasites (3.63 to −5.09) and metagranitoids (3.29 to −5.76) indicate that the metabasites were formed from 1.67–1.32 Ga depleted mantle and the metagranitoids were formed by the reworking of ancient crust, which formed from 2.14–1.57 Ga depleted mantle. The metabasites in the Maldo Formation underwent intermediate-P/T amphibolite-facies metamorphism (4.35 ± 1.15 kbar and 465 ± 15 °C) with strong deformation before the deposition of the Bangchukdo Formation, indicating a collision event. The Bangchukdo Formation was deposited after 792–763 Ma in the rifting tectonic setting. The data in this and previous studies suggest that the Neoproterozoic igneous rocks in the Gogunsan Islands can be correlated to arc-related Neoproterozoic rocks formed during the Jiangnan orogeny on the southern margin of the Yangtze Block in the South China Craton. Along the Jiangnan orogenic belt, the arc stage was followed by the collision between the Yangtze and Cathaysia Blocks. The collision may have started in the Korean Peninsula and propagated westwards into South China.

Climate response to introduction of the ESA CCI land cover data to the NCAR CESM

The European Space Agency Climate Change Initiative Land Cover data (ESA CCI-LC, from 1992 to 2015) is introduced to the National Center for Atmospheric Research Community Earth System Model version 1.2.1 (NCAR CESM1.2.1). In comparison with the original land surface data in the Community Land Model version 4 (ORG), the new data features notable land use and land cover change (LULCC) with increased forests over northeastern Asia and Alaska by decreasing shrublands and grasslands. Overestimated bare land cover over the Tibetan Plateau (TP) and the Rocky Mountains in the ORG are corrected with the replacements by grasslands and shrublands respectively in the new data. The model simulation results show that with the introduction of the ESA CCI-LC, the simulated surface albedo, surface net radiation flux, sensible and latent heat fluxes are relatively improved over the regions where significant LULCC exists, such as northeastern Asia, Alaska, the TP, and Australia. Surface air temperature, precipitation, and atmospheric circulation are improved in boreal winter but degraded in summer. The winter warming over northeastern Asia results from increased longwave downwelling flux and adiabatic heating while the notable winter cooling over Alaska is attributed to strong cold advection followed by reduced longwave downwelling flux. LULCC alters precipitation by influencing water vapor content. In winter, LULCC affects atmospheric circulation via modulating baroclinicity while in summer, it influences land-sea thermal contrast, thus affecting the intensity of East Asian summer monsoon. LULCC also alters the simulated dust burden.

Using Genomics to Link Populations of an Invasive Species to Its Potential Sources

The introduction and subsequent range expansion of the Northern snakehead (Channa argus: Channidae, Anabantiformes) is one of a growing number of problematic biological invasions in the United States. This harmful aquatic invasive species is a predatory freshwater fish native to northeastern Asia that, following deliberate introduction, has established itself in multiple water basins in the eastern United States, as well as expanding its range into the Midwest. Previous work assessed the population structure and estimated the long-term effective population sizes of the populations present in the United States, but the source of the initial introduction(s) to the U.S. remains unidentified. Building on earlier work, we used whole genome scans (2b-RAD genomic sequencing) to analyze single nucleotide polymorphisms (SNPs) from C. argus to screen the genomes of these invasive fish from United States waters and from three sites in their native range in China. We recovered 2,822 SNP loci from genomic DNA extracted from 164 fish sampled from the eastern United States and Arkansas (Mississippi River basin), plus 30 fish sampled from three regions of the Yangtze River basin in China (n = 10 individuals per basin). Our results provide evidence supporting the Yangtze River basin in China, specifically the Bohu and/or Liangzi lakes, is a likely source of the C. argus introductions in multiple regions of the U.S., including the Lower Hudson River basin, Upper Hudson River basin and Philadelphia (Lower Delaware River basin). This information, in conjunction with additional sampling from the native range, will help to determine the source(s) of introduction for the other U.S. populations. Additionally, this work will provide valuable information for management to help prevent and manage future introductions into United States waterways, as well as aid in the development of more targeted strategies to regulate established populations and inhibit further spread.

Практика межкультурного диалога в деятельности Приморской сцены Мариинского театра

The article examines activity of Mariinsky Theatre Primorsky Stage in the context of intercultural dialogue in the Asian-Pacific region. The researcher’s attention is focused on the following issues: the theatre repertoire policy, the role of festival movement in developing creative cooperation between Russia and countries of North-eastern Asia. Scientific originality of the study lies in the fact that for the first time in domestic musicology, the author analyses essential characteristics of intercultural activity of the youngest theatre in the country. The following conclusions are justified: Vladivostok theatre cross-cultural strategy makes it possible to consider this scenic concert venue the epicentre of cultural life of the Russian Far East.

Contribution of precipitation events with different consecutive days to rainfall change over Asia during ENSO years

The present study investigates the contributions of four types of precipitation events with different consecutive days (1–3-day, 4–7-day, 8–14-day, and over-14 day) of precipitation to April–October rainfall anomalies over Asia and roles of the three factors (intensity, number, duration) in area-mean rainfall anomalies of four types of precipitation events in El Nino and La Nina years. It is found that precipitation tends to be below normal in the entire tropical and extratropical regions except for northeastern Asia and east and west Indochina Peninsula during El Nino years. During La Nina years, precipitation tends to increase in eastern China, India, the south hills of the Himalayas, west Indochina Peninsula-southwest China, and the Maritime Continent, but decreases in northeast China, east Kazakhstan, Afghanistan, and east Indochina Peninsula. The precipitation change at the low latitudinal regions has a larger contribution from the over-14-day events. The number of events is a main factor in changes of precipitation of primary events during El Nino years. The precipitation changes in El Nino and La Nina years are consistent with changes in the activity of cyclonic wind anomalies corresponding to the precipitation events. The intraseasonal wind anomalies leading to the precipitation events in China are preceded by northwestward move of cyclonic systems from the tropical western North Pacific that promotes the start of precipitation in the concerned regions. The present study points to the impacts of intraseasonal wind systems with various lifespans on precipitation changes over Asia in El Nino and La Nina years.

A Review of Recently Discovered Remains of the Pleistocene Branchiopods (Anostraca, Notostraca) from NE Siberia and Arctic Canada

In this study, we examine, identify, and discuss fossil remains of large branchiopod crustaceans collected from six sites across the Beringian region (north-eastern Asia and north-western North America). Eggs and mandibles from Anostraca and Notostraca, as well as a notostracan telson fragment and a possible notostracan second maxilla, were collected from both paleosediment samples and also from large mammal hair. The remains of large branchiopods and other species that are limited to seasonally astatic aquatic habitats (temporary wetlands) could be useful indicator organisms of paleoecological conditions. Different recent large branchiopod species have very different ecological preferences, with each species limited to specific geochemical component tolerance ranges regarding various salinity, cation, and gypsum concentrations. Our purpose is to bring the potential usefulness of these common fossil organisms to the attention of paleoecologists.

Decoding the dramatic hundred-year water level variations of a typical great lake in semi-arid region of northeastern Asia

Lakes in arid and semi-arid regions are experiencing dramatic variations in water level and volume, which has caused severe ecological and social problems. Long-term study of the lake dynamics in arid/semi-arid regions could provide particular insights into the mechanisms driving lake variations, while hydro-meteorological data were usually limited in these regions, especially before the instrumental period. In the present study, we focused on a typical great lake – Hulun Lake in semi-arid region in northern China, simulated the hydrological processes from 1904 to 2016 using SWAT model, CRUNCEP7 reanalysis data, and sparse records of lake level during 1900s–1950s, and investigated the mechanisms driving the dramatic variations of the lake at the hundred-year time scale. Results illustrated that the simplified Penman equation by Valiantzas (2006) could reproduce the evaporation dynamics of Hulun Lake, with monthly R2 being 0.93–0.95. The long-term simulation since 1904 reproduced runoff dynamics, which were consistent with the dramatic variations of lake level over hundred years. The largest water level increase (~5.0 m in 1950s) and decrease (~4.5 m in 2000s) during 1904–2016 were jointly affected by river runoff, lake evaporation, and precipitation into the lake. Both the positive/negative phase and the multi-decadal trend of PDO clearly influenced the hydrological cycle of Hunlun Lake, especially for the period of 1904–1950 with low lake levels. Overall, the present study provided a methodology for investigating the hundred-year hydrological processes for lakes in semi-arid regions in northeastern Asia.

A new species of Leptoplectus Casey from Ryukyu Islands, Japan, with comments on morphology of integumental structures in Euplectitae (Coleoptera, Staphylinidae, Pselaphinae).

Leptoplectus kijimunaa Jałoszyński Nomura, sp. n. is described, based on a series of specimens collected on Okinawa Island, Japan. Morphological structures of the new species are illustrated in detail and compared to known characters of all remaining 14 congeners. As the diagnosis of Leptoplectus remains unclear, character variability within known species is discussed. It is concluded that within Palaearctic region, the bilobed labrum is a reliable character to distinguish this genus from other Euplectini. The placement of Labroplectus Kurbatov, treated as incertae sedis within the tribe Trichonychini in the latest edition of the Catalogue of Palaearctic Coleoptera, is verified and it is concluded that it should be maintained in Euplectini. An identification key to genera of northeastern Asian Euplectini is given. We also comment on outdated and inaccurate morphological nomenclature still broadly used in descriptions of new Pselaphinae taxa.

Further studies on harvestman genus Homolophus (Opiliones: Phalangiidae), with descriptions of two new species.

A key to the members of the subfamily Opilioninae is presented, including the genus Homolophus. That same genus is briefly reviewed, diagnosed, and redescribed based upon a study of approximately half of the described species. Many older museum specimens from the Zoological Institute (Saint-Petersburg, Russia) were identified and all species present were redescribed. A list of the 29 currently accepted species (all from Northeastern and Central Asia) is presented along with a list of another four species that their validity and proper inclusion in the genus are questioned (still need to be investigated extensively). Descriptions and redescriptions with many illustrations are presented for two new species and 15 previously described species of Homolophus: H. albofasciatus (Kulczyński, 1901); H. almasyi (Roewer, 1911); H. andreevae Staręga Snegovaya, 2008; H. arcticus Banks, 1893; H. asiaticus (Gricenko, 1979a); H. betpakdalensis (Gricenko, 1976); H. charitonovi (Gricenko, 1972); H. chemerisi Staręga Snegovaya, 2008; H. chevrizovi Staręga Snegovaya, 2008; H. gobiensis Tsurusaki, Tchemeris Logunov, 2000; H. kozlovi sp. nov.; H. martensi (Staręga, 1986); H. milkoi sp. nov.; H. nordenskioeldi (L. Koch, 1879a); H. pallens (Kulczyński, 1901); H. silhavyi Staręga Snegovaya, 2008; H. tibetanus (Roewer, 1911); H. vladimirae (Šilhavý, 1967). New country distributional records are detailed for nine species, not including those for the two new species. Three new combinations with Homolophus (H. almasyi, H. asiaticus, H. charitonovi) are recognized for Opilio almasyi Roewer, 1911, Opilio asiaticus Gricenko, 1979a, and Globipes charitonovi Gricenko, 1972.

Prehistoric Mongolian Archaeology in the Early 21st Century: Developments in the Steppe and Beyond

There has been a great increase in archaeological research in Mongolia since 2000. Increasingly precise chronologies, regional studies, and the growth of development-driven archaeology are transforming our knowledge of this key region of northeastern Asia. This review summarizes recent work and provides a narrative of the prehistoric and medieval cultural sequences as presently understood. I focus on long-standing key topics: early human habitation, the adoption of food-producing economies, Bronze Age social transformations, and the emergence of central places and large polities. I argue that, on the one hand, Mongolia has unique data and new examples to offer the archaeological community and, on the other, that the prehistory of Mongolia and the steppe are not so different from the rest of the world in its history of research and key questions. This review provides general overviews covering the Upper Paleolithic, Epipaleolithic or Neolithic, and Bronze Age to the Xiongnu period; specific data related to each period provide jumping-off points for comparative analysis and further examination.

Molecular phylogeny and ancestral biogeographic reconstruction of Platanthera subgenus Limnorchis (Orchidaceae) using target capture methods

Platanthera is one of the largest genera of temperate orchids in the Holarctic and exemplifies a lineage that has adaptively radiated into diverse habitats within North America, Asia, Europe, North Africa, Borneo, and Sarawak. Major centers of diversity in this genus are North America and eastern Asia. Despite its diversity, a thorough phylogenetic hypothesis for the genus is lacking because no studies have yet sampled taxa exhaustively or developed a robust molecular toolkit. While there is strong evidence that suggests monophyly of subgenus Limnorchis, most taxa in this group have not been included in a phylogenetic analysis. In this study, we developed a new toolkit for Platanthera consisting of genomic information from 617 low-copy nuclear loci. Using a targeted enrichment approach, we collected high-throughput sequence data in 23 accessions of nine of the 12 diploid species of subgenus Limnorchis and outgroup species across Platanthera. A maximum likelihood analysis resolved a strongly supported monophyletic clade for subgenus Limnorchis. Ancestral biogeographic reconstruction indicated that subgenus Limnorchis originated in western North America ca. 3–4.5 Mya from an ancestor that was widespread in western North America and eastern Asia and subsequently diversified in western North America, followed by dispersal of some species to eastern North America. Our results indicate complex biogeographic connections between Asia and North America, and therefore it suggests that Platanthera is a suitable system to test biogeographic hypotheses over time and space in the Holarctic. Our results are also expected to facilitate further study of diversification and biogeographic spread across Platanthera and lay the groundwork for understanding independent origins, biogeography, and morphological diversification of polyploid species within subgenus Limnorchis.

Mapping rice area and yield in northeastern asia by incorporating a crop model with dense vegetation index profiles from a geostationary satellite

ABSTRACT Acquiring accurate and timely information on the spatial distribution of paddy rice fields and the corresponding yield is an important first step in meeting the regional and global food security needs. In this study, using dense vegetation index profiles and meteorological parameters from the Communication, Ocean, and Meteorological Satellite (COMS) geostationary satellite, we estimated paddy areas and applied a novel approach based on a remote sensing-integrated crop model (RSCM) to simulate spatiotemporal variations in rice yield in Northeastern Asia. Estimated seasonal vegetation profiles of plant canopy from the Geostationary Ocean Color Imager (GOCI) were constructed to classify paddy fields as well as their productivity based on a bidirectional reflectance distribution function model (BRDF) and adjusted normalized difference vegetation indices (VIs). In the case of classification, the overall accuracy for detected paddy fields was 78.8% and the spatial distribution of the paddy area was well represented for each selected county based on synthetic applications of dense-time GOCI vegetation index and MODIS water index. For most of the Northeast Asian administrative districts investigated between 2011 and 2017, simulated rice mean yields for each study site agreed with the measured rice yields, with a root-mean-square error of 0.674 t ha−1, a coefficient of determination of 0.823, a Nash-Sutcliffe efficiency of 0.524, and without significant differences (p-value = 0.235) according to a sample t-test (α = 0.05) for the entire study period. A well-calibrated RSCM, driven by GOCI images, can facilitate the development of novel approaches for the monitoring and management of crop productivity over classified paddy areas, thereby enhancing agricultural decision support systems.