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Fagopyrum dibotrys, belonging to the family Polygonaceae and genus Fagopyrum, is used in traditional Chinese medicine and is rich in beneficial components, such as flavonoids. As its abundant medicinal value has become increasingly recognized, its excessive development poses a considerable challenge to wild germplasm resources, necessitating artificial cultivation and domestication. Considering these factors, a high-quality genome of F. dibotrys was assembled and the evolutionary relationships within Caryophyllales were compared, based on which 58 individual samples of F. dibotrys were re-sequenced. We found that the samples could be categorized into three purebred populations and regions distributed at distinct elevations. Our varieties were cultivated from the parental populations of the subpopulation in central Yunnan. F. dibotrys is speculated to have originated in the high-altitude Tibetan Plateau region, and that its combination with flavonoids can protect plants against ultraviolet radiation; this infers a subpopulation with a high accumulation of flavonoids. This study assembled a high-quality genome and provided a theoretical foundation for the future introduction, domestication, and development of cultivated varieties of F. dibotrys. [ABSTRACT FROM AUTHOR]

Modern pollen datasets are essential for pollen-based quantitative paleoclimate (e.g. precipitation) reconstructions, which can aid to better understand recent climate change and its underlying forcing mechanisms. A modern pollen dataset based on surface sediments from 90 lakes in the shrub, meadow, steppe and desert regions of the central and western Tibetan Plateau (TP) was established to fill geographical gaps left by previous datasets. Ordination analyses of pollen data and climatic parameters revealed that annual precipitation is the dominant factor for modern pollen distribution on the central and western TP. A regional transfer function for annual precipitation was developed with the weighted averaging partial least squares (WAPLS), which suggests a good inference power of the modern pollen dataset for annual precipitation. A case study in which the transfer function was effectively applied to a fossil pollen record from Lake Tangra Yumco on the central TP for paleoprecipitation reconstruction demonstrated the significance of the modern pollen dataset in less data region for paleoclimate change studies. Data from this study are openly available via the Zenodo portal (Ma et al., 2023; https://doi.org/10.5281/zenodo.8008474). [ABSTRACT FROM AUTHOR]

Both South Asia and East Asia are the most polluted regions of the world. Unlike East Asia, the aerosol optical depth (AOD) over South Asia keeps increasing for all recent years, which calls for more attention. This study investigates the impacts of anthropogenic emissions over South Asia on the downstream regional climate during spring with the Community Earth System Model 2 (CESM2). The model results suggest that South Asian pollutants have significant impacts on East Asian spring climate, and the impacts could be even larger than locally emitted aerosols. Two possible dynamical pathways (i.e., the northern and the southern pathways) bridging South Asian aerosol forcing and East Asian climate are proposed, and both ways are associated with the black carbon (BC)-induced climate feedbacks surrounding the Tibetan Plateau (TP). The northern pathway is mainly due to the TP warming induced by the BC snow darkening effect (SDE), which significantly reduces the surface air temperature (SAT) over northern East Asia. BC-induced TP warming increases the meridional thermal gradient and accelerates the midlatitude jet stream, which favors the cold-air advection over northern East Asia. The southern pathway is associated with the BC "elevated heat pump" hypothesis, which mainly affects the precipitation in southern East Asia. BC from South Asia accumulates near the south slope of TP, inducing an abnormal ascending motion near the Bay of Bengal. A compensating anomalous sinking motion is then forced in South China, which suppresses the precipitation there. A primary observational analysis is also performed to verify both dynamical pathways. [ABSTRACT FROM AUTHOR]

Endophytes in the seeds of plants have shown plant growth promoting (PGP) properties. Highland barley is an economically important crop and a major part of the local diet in the Tibetan Plateau, China, with potential health benefits. We applied culture-dependent and culture-independent methods to study endophytic bacteria in the seeds of eight Highland barley varieties. Based on the seed properties, the variety Ali was clearly separated from the other varieties except the variety CM. Most of the 86 isolates were assigned into genus Bacillus. Approximately half of the isolates showed PGP properties in vitro. Compared to the not-inoculated plants, inoculation with the isolate Bacillus tequilensis LZ-9 resulted in greater length and number of roots, and in bigger aboveground and root weights. Based on the 16S rRNA gene sequencing, the seed microbiome was majorly affiliated with the phylum Proteobacteria and the family Enterobacteriaceae. Overall, the bacterial community compositions in the different varieties were different from each other, yet the between variety differences in community composition seemed relatively small. The differences in community compositions were associated with differences in the total and reducing sugar contents and viscosity of the seeds, thus possibly connected to differences in the osmotic pressure tolerance of the endophytes. The results suggested that the seed endophytes are likely to promote the growth of Highland barley since germination. [ABSTRACT FROM AUTHOR]

The shallow seismic velocity structure of the Kunlun fault zone (KLFZ) was jointly deduced from seismic refraction profiling and the records of trapped waves that were excited by five explosions. The data were collected after the 2001 Kunlun Ms8.1 earthquake in the northern Tibetan Plateau. Seismic phases for the in-line record sections (26 records up to a distance of 15 km) along the fault zone were analysed, and 1-D P- and S-wave velocity models of shallow crust within the fault zone were determined by using the seismic refraction method. Sixteen seismic stations were deployed along the off-line profile perpendicular to the fault zone. Fault-zone trapped waves appear clearly on the record sections, which were simulated with a 3-D finite difference algorithm. Quantitative analysis of the correlation coefficients of the synthetic and observed trapped waveforms indicates that the Kunlun fault-zone width is 300 m, and S-wave quality factor Q within the fault zone is 15. Significantly, S-wave velocities within the fault zone are reduced by 30–45 per cent from surrounding rocks to a depth of at least 1–2 km, while P-wave velocities are reduced by 7–20 per cent. A fault-zone with such P- and S-low velocities is an indication of high fluid pressure because Vs is affected more than Vp. The low-velocity and low- Q zone in the KLFZ model is the effect of multiple ruptures along the fault trace of the 2001 Ms8.1 Kunlun earthquake. [ABSTRACT FROM AUTHOR]

The n-alkanes are extracted from NMLC-1 core that was drilled in the Nam Co, central Tibet. They are measured by using Gas Chromatography and Mass Spectrometry (GC/MS) for componential and quantitative analyses. According to the constructed depth-age model, the component and concentration of n-alkanes, together with total organic carbon (TOC), total nitrogen (TN) and carbonate are used to elucidate palaeoenvironmental changes of Nam Co during the past 8.4 ka. The results indicate that Holocene environment performs three stages in the lake area. In the stage of 8.4-6.7 kaB.P., it was warmer while precipitation slightly increased. This stage was ended by an obvious cold/dry event. During 6.7- 5.8 kaB.P., temperature increased rapidly and reached its maximum values at about 6.0 kaB.P. The environments were warm/wet optimum for the blooming of terrestrial plants and submerged aquatic plants. After that, temperature decreased continuously and showed the lowest values at about 3.0 kaB.P. From 2.9 kaB.P. to the present, temperature rose again but alternated with cold and warm. The lake area tended to be dry after 1.4 kaB.P. During 600-400 aB.R, the environmental feature was the reflection of "Little Ice Age". [ABSTRACT FROM AUTHOR]

The recent dramatic increase in seismic anisotropy and surface global positioning system (GPS) data for central Asia permits a comprehensive examination of the mantle's role in mountain building. A joint analysis of 178 shear-wave-splitting and 2000 GPS observations using a new technique reveals that the crust and lithospheric mantle deform coherently, arguing for crust-mantle mechanical coupling during deformation. The observed spatial variations in anisotropy reflect the large-scale pattern of lithospheric deformation, as well as a change in deformational style from simple shear on the Tibetan Plateau transitioning to pure shear in surrounding regions. [ABSTRACT FROM AUTHOR]

Presents a study which monitored the uplift of the Tibetan Plateau using the FG5 absolute gravimeter. Observational accuracy of absolute gravimeter FG5; Results of absolute gravimetry at Lhasa station in China and analysis of its errors; Gravity decrease and uplift at Lhasa.

In the southern Tibetan Plateau, leucogranites are dominantly distributed in the Himalayan orogenic belt with minor occurrences in the southern Lhasa subterrane. In this paper, we report the first Miocene Anglonggangri leucogranites in the northern Lhasa subterrane. This finding provides important constraints on both leucogranite petrogenesis and the tectono-magmatic evolution of the Lhasa terrane. The Anglonggangri leucogranites include biotite-muscovite granite and slightly younger garnet-muscovite granite and pegmatite. Zircon U-Pb and muscovite 40Ar-39Ar dating of these leucogranites yields Miocene ages of 11.1-10.2 Ma. The biotite-muscovite and garnet-muscovite granites are characterized by high SiO2 (72.3-74.4 wt.%) and Al2O3 contents (14.4-15.4 wt.%) and are peraluminous. The biotite-muscovite granite displays geochemical signatures with high Sr/Y (29.2-81.0) and (La/Yb)N (37.5-98.9) ratios, low Y (4.30-7.22 ppm) and Yb contents (0.26-0.47 ppm), low to moderate initial (87Sr/86Sr)i ratios (0.7085-0.7192), and moderate εNd(t) values (-10.17 to -6.94). Furthermore, they also exhibit radiogenic Pb isotope and variable zircon εHf(t) values (-9.6 to +4.4) with Proterozoic Nd (1.1-1.4 Ga) and Hf model ages (0.8-1.7 Ga). By comparison, the garnet-muscovite granite has lower CaO, MgO, TiO2, and total FeO contents and is enriched in Rb (380-466 ppm) and depleted in Sr (24.1-38.5 ppm) and Ba (30.7-58.6 ppm) and further characterized by a significant rare earth element (REE) tetrad effect and non-charge and radius-controlled (CHARAC) trace element behaviors. The garnet-muscovite granite shows a negative Eu anomaly and positive correlations among Sr and Eu, Sr and Ba, and Th and light rare earth elements (LREEs). Pegmatite comprising Nb-Ta oxides and cassiterite occurs in the garnet-muscovite granite. Geochronological and geochemical characteristics of the Anglonggangri leucogranites indicate that the magma of the biotite-muscovite granite was derived from partial melting of amphibolite lower crust contaminated with Proterozoic-Archean upper crustal materials. The garnet-muscovite granite was generated through melt extraction from the biotite-muscovite granite crystal mush. These results confirm that partial melting of the amphibolite lower crust not only occurred in the southern and central Lhasa subterranes but also in the northern Lhasa subterrane. [ABSTRACT FROM AUTHOR]