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[Objective] The water chemical characteristics and irrigation suitability evaluation of surface water body in areas around Yuelu Mountain in Xiangjiang River basin were analyzed in order to provide theoretical support for ecological environment protection and scientific decision-making of integrated water resources management in this area. [Methods] The study was conducted in the area around Yuelu Mountain. Water samples of precipitation, mountainous creek water, and Xiangjiang River water were collected from December 2020 to November 2021. The water chemical characteristics and factors influencing each water body were analyzed by using Piper diagram, Gibbs diagram, end-member diagram, etc. [Results] The main anions and cations of precipitation were Ca2+, K+, SO2-4, and NO-3, with no obvious water chemical type. The main anions and cations of mountainous creek water were Ca2+ and NO-3, and the water chemical types were Cl-Ca·Mg and Cl-Ca. The main anions and cations of Xiangjiang River water were Ca2+ and HCO-3, and the water chemical type was HCO3-Ca. Mountainous creek water was primarily influenced by atmospheric precipitation and carbonate rock weathering, whereas Xiangjiang River water was more influenced by carbonate rock weathering. [Conclusion] Na+%, SAR, and RSC indexes, and the USSL diagram and Wilcox diagram results were good. The mountainous creek water and Xiangjiang River water in the areas around Yuelu Mountain are suitable for irrigation and are not prone to salt or alkali damage.

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The Tian Shan mountain range, known as the water towers of Central Asia, plays a key role in local water supply, yet large uncertainties remain about the amount of water that is stored in its glaciers. In this study, we assess the impact of the boundary conditions on ice thickness estimates using two inversion models: a mass conservation (MC) model and a basal shear stress (BS) model. We compare the widely used Randolph Glacier Inventory version 6 with the updated Glacier Area Mapping for Discharge from the Asian Mountains glacier inventory, as well as two digital elevation models (SRTM DEM and Copernicus DEM). The results show that the ice volume (in ~2000 CE) in the Tian Shan range is 661.0 ± 163.5 km3 for the MC model and 552.8 ± 85.3 km3 for the BS model. There are strong regional differences due to inventory, especially for glaciers in China (17–25%). However, the effect of different DEM sources on ice volume estimation is limited. By the end of the 21st century, the projected mass loss differences between inventories are higher than between adjacent emission scenarios, illustrating the vital importance of high-quality inventories. These differences should be carefully considered during water resource planning. [ABSTRACT FROM AUTHOR]

Pressure on river water resources may increase continuously under global climate change and the increasing intensity of human activity, and the identification of river water sources is needed to maintain water resource sustainability. In this study, river water sources were studied using hydrochemical tracers (i.e. the major ions) and end‐member mixing analysis (EMMA) during two hydrological years, in the subtropical monsoon basin of the Xiangjiang River in the south‐central China. Various water types including precipitation, river water, and mountain creek water, were collected in the basin at a high frequency. The results of EMMA showed that the average contributions from the direct input of precipitation, near‐surface runoff (represented by mountain creek water), and groundwater (represented by river water sampled during the base flow period) were 28 ± 24%, 49 ± 24% and 23 ± 16%, respectively. The contributions from these water sources to the river water varied greatly within the year, which may indicate a shift in the major flow pathways from direct precipitation input and near‐surface flow pathways in the spring rainy months (e.g. from March to May), to a deeper flow pathway in the dry or rainless months (e.g. January, February, July and December). The shift of the major flow pathways may be due to the factors such as the seasonality of precipitation, evapotranspiration and soil wetness conditions. Groundwater and near‐subsurface runoff dominated the river water and the direct input of precipitation was negligible during the dry or rainless months, and consequently, the river water chemistry was less diluted and more influenced by water‐soil/rock interactions and anthropogenic pollution during these months. The creek water contribution to the river water was relatively high in summer, especially in June and July 2021, which may indicate the substantial inter‐seasonal carryover of precipitation that contributed to the river water. With the projected increased frequency of extreme weather events such as seasonal drought, streamflow in the subtropical monsoon regions may experience greater recharge by deeper flow pathways, with the enhanced role of base flow in regulating streamflow, and there may be an increased risk to the water resource security under the condition of the decreased river dilution capacity and increased anthropogenic pollution. [ABSTRACT FROM AUTHOR]

The melting behavior of glaciers on and around the Tibetan Plateau is strongly influenced by their albedo. In this paper, we report continuous observations made on the Qiangtang (QT) No. 1 Glacier, located in the central Tibetan Plateau, during its 2013–2015 melting seasons. Surface snow on the QT No. 1 Glacier mainly had a dust content less than 600 ppm and a black carbon (BC) content less than 10 ppb. A strong negative correlation was observed between albedo and dust content up to a threshold concentration of 1000 ppm, although albedo remained constant when dust concentrations increased above this value. The radii of snow particles showed a log-normal distribution that had a mean value of ~500 μm, but maximum and minimum values of 2539 μm and 40 μm, respectively. Snow density showed a normal distribution with a total range of 193–555 kg/m3, although most snow had a density of 400 kg/m3. Snow, ice, and aerosol radiative (SNICAR) simulations showed that dust and BC in the surface snow of the QT No. 1 Glacier reduced the snow and ice albedo by 5.9% and 0.06%, respectively, during the ablation season in 2015; however, the simulated particle impact was greater than the albedo reduction measured from field data. We interpret that dust has played a significantly more important role in melting of the QT No. 1 Glacier than BC over the study period, which is mainly due to the scarcity of human activities in the region and the low concentration of BC being produced. [ABSTRACT FROM AUTHOR]

To deeply understand the dynamics of gas–water displacement in fractured porous media, especially under extreme high-pressure conditions, is essential to prevent water invasion in natural gas reservoirs. To this end, we presented an experimental study on the interfacial dynamics of gas–water displacement in a microfluidic device with fractured porous media, in which the displacement pressure could reach as high as 25 MPa. We found that, under the condition of quasi-static imbibition (i.e., at quite low differential pressure), water preferentially invaded the matrix instead of the fracture. In contrast, invasive water tended to permeate the fracture under high differential pressure; as a consequence, a conical front edge was formed at the gas–water displacing interface. More importantly, the interfacial front in different fractures contacted at the cross junctions and led to the formation of trapped gas in the matrix, due to the velocity of gas–water interface in the fracture being higher than that in the matrix. Besides, with increase in differential pressure and fracture number, the difference in the interfacial velocity between fractures and the matrix increased and hence the gas in the matrix was more easily trapped. Finally, we established a theoretical model to predict the interfacial velocity of gas–water displacement in fractured porous media under high pressure, which was able to well reproduce experimental data. [ABSTRACT FROM AUTHOR]

Y chromosomal short tandem repeats (Y‐STRs) have been applied overwhelmingly in forensic areas for solving paternity identification and sexual assault cases. Yet the widely used Y‐STR kits contain mostly single‐copy markers, which may restrict the discrimination power. Here, a novel Y‐STR multiplex was developed and validated in order to complement the currently available Y‐STR kits, especially on differentiating male relatives. The assay includes twelve multicopy Y‐STR loci (DYF371, DYF383S1, DYS385, DYF387S1, DYS389I/II, DYF399S1, DYF404S1, DYF409S1, DYF411S1, DYS464, DYS526, DYS527; four of them are rapidly mutating ones), 1 single‐copy Y‐STR (DYS391), and Amelogenin, and was optimized to amplify at annealing temperature of 59°C and 28 cycles. Validation studies show that full profiles are obtained with 0.125 ng of male DNA. The system is capable of overcoming high concentrations of inhibitors such as hematin, EDTA, and humic acid. Besides, the results demonstrate good sizing precision and the ability to detect male‐specific profiles in male/female DNA mixtures at a ratio of 1:800. Excellent species specificity was also observed in microorganisms and non‐primates, while detectable peaks were found in some primates. Based on published genetic data, gene diversity values were above 0.7 for most of the loci in our multiplex, inferring a high capacity in discriminating unrelated and related male individuals. The kit is of great potential for forensic application. [ABSTRACT FROM AUTHOR]

Climate factors play critical roles in controlling chemical weathering, while chemically weathered surface material can regulate climate change. To estimate global chemical weathering fluxes and CO2 balance, it is important to identify the characteristics and driving factors of chemical weathering and CO2 consumption on the Tibetan Plateau, especially in glaciated catchments. The analysis of the hydro‐geochemical data indicated that silicate weathering in this area was inhibited by low temperatures, while carbonate weathering was promoted by the abundant clastic rocks with fresh surfaces produced by glacial action. Carbonate weathering dominated the riverine solute generation (with a contribution of 58%, 51%, and 43% at the QiangYong Glacier (QYG), the WengGuo Hydrological Station (WGHS), and the lake estuary (LE), respectively). The oxidation of pyrite contributed to 35%, 42%, and 30% of the riverine solutes, while silicate weathering contributed to 5%, 6%, and 26% of the riverine solutes at the QYG, WGHS, and LE, respectively. The alluvial deposit of easily weathering fine silicate minerals, the higher air temperature, plant density, and soil thickness at the downstream LE in comparison to upstream and midstream may lead to longer contact time between pore water and mineral materials, thus enhancing the silicate weathering. Because of the involvement of sulfuric acid produced by the oxidation of pyrite, carbonate weathering in the upstream and midstream did not consume atmospheric CO2, resulting in the high rate of carbonate weathering (73.9 and 75.6 t km−2 yr−1, respectively, in maximum) and potential net release of CO2 (with an upper constraint of 35.6 and 35.2 t km−2 yr−1, respectively) at the QYG and WGHS. The above results indicate the potential of the glaciated area of the Tibetan Plateau with pyrite deposits being a substantial natural carbon source, which deserves further investigation. [ABSTRACT FROM AUTHOR]

In this study, 31 samples were selected from two ice cores collected from Aru and Guriya glaciers in the TP, and four water-soluble metal ions, K+, Na+, Ca2+ and Mg2+, were analyzed and compared with these three instruments to seek for the best analysis scheme. The results show that IC and ICP-MS can both meet the requirements except ICP-OES, especially in K+ analysis. The results were highly consistent, with the correlation coefficients (R²) all above 0.97 and there is no evidence that the measured values from ICP-MS are higher than that from IC. Therefore, in addition to IC, ICP-MS is also an effective method to determine water-soluble metal ions in snow and ice samples from the TP. Meanwhile, the analysis speed of ICP-MS is much faster than IC, and micro and trace elements can also be determined at the same time, which means ICP-MS is very suitable for the rapid analysis of large quantities of ice core samples. [ABSTRACT FROM AUTHOR]

The Tibetan Plateau (TP) has encountered rapid warming, with more than 50% of lakes expanding and 80% of glaciers retreating. Melting glaciers are known as a secondary source of pollutants, but the dynamics and release features of water‐soluble emerging chemicals have not been studied in the TP. Glacial ice and snow, meltwater runoff, rain, and lake water were collected in Nam Co basin, in the central TP. The total concentrations of perfluoroalkyl acids (PFAAs) were 1,413 pg/L for glacial ice, followed by 1,277 pg/L for meltwater runoff, 980 pg/L for lake water, and 616 pg/L for rain. Perfluorobutanoic acid is dominant in runoff and glacial ice, while lake water contained high proportions of perfluorobutane sulfonate and perfluorooctane sulfonate. During the melting season, meltwater runoff generally had greater PFAAs concentrations, and the PFAAs release fluxes were strongly related to the glacial melt intensity. Due to the direct input of PFAAs by melted glaciers, south shore of Lake Nam Co contained higher PFAAs concentrations. The estimated input fluxes of PFAAs to the lake by rain and glacial and nonglacial runoff were 1,425, 1,342, and 2,192 mg/day, respectively. Taken together, these evidences suggest that melting glaciers are sources of PFAAs, while the lake is the receptor. Given the continuity of glacial melt and high concentrations of water‐soluble emerging pollutants in glacier, the melting process will increase the risks of emerging pollutants to freshwater sources and should be of great concern. Key Points: The PFASs released by glaciers have become a secondary source of PFASs in Lake Nam Co in the central Tibetan PlateauPFAA transport dynamics in glacial runoff is related to the chain length of PFAAs and the melting process of ice and snowPrecipitation and glacial and nonglacial runoffs contribute 27.1%, 28.7%, and 44.2% of the total annual PFAAs input in Lake Nam Co, respectively [ABSTRACT FROM AUTHOR]

Following the introduction of models based on the immune system, new algorithms suitable for processing analytical signals are described. By imitating the defense mechanism of the immune system, the algorithms iteratively eliminate antigens (multi-component analytical signals) with antibodies (standard signals of assumed components) until the remaining antigens (residual signal) approach a minimum and do not change. By using these algorithms, information can be obtained for each component to provide a quantitative result. Applications of these algorithms to the resolution of chromatograms, photoacoustic spectra, nuclear magnetic resonance (NMR) signals and two-dimensional chromatograms are summarized. [Copyright &y& Elsevier]

Groundwater is the most unexplored element of the hydrologic cycle on the Tibetan Plateau (TP) due to harsh climate conditions. This study aims at delineating and characterizing the unexplored Zhanongtang–Ganmanong aquifer, situated in the Zhagu subcatchment of the Nam Co catchment, south-central TP. Multiple hydrogeophysical and lithological in situ field and laboratory methods are applied: depth-to-water-table measurements, grain size analysis, hydraulic empirical and field methods to estimate hydraulic conductivity (K), and analysis of electrical resistivity tomography profiles. Integration of these methods revealed the existence of a Quaternary hydrostratigraphic unit that was found to be unconsolidated, laterally heterogeneous and homogeneous over depth. The results revealed consistent K ranges of three K zones, which is in accordance with local lithology. The K ranges are applicable to other locations within the Nam Co catchment with similar lithology as in the study area without further field experiments. Permafrost was found to be absent in the study area ranging from 4730 m a.s.l. to 5200 m a.s.l. altitude. These results provide insight into the hydrogeological conditions of the TP and are useful for conceptual and numerical groundwater flow modeling to predict future changes of water fluxes and water budgets caused by climatic change, especially in remote areas. [ABSTRACT FROM AUTHOR]

Glacierized mountain environments can preserve and release mercury (Hg) and play an important role in regional Hg biogeochemical cycling. However, the behavior of Hg in glacierized mountain environments and its environmental risks remain poorly constrained. In this research, glacier meltwater, runoff and wetland water were sampled in Zhadang-Qugaqie basin (ZQB), a typical glacierized mountain environment in the inland Tibetan Plateau, to investigate Hg distribution and its relevance to environmental risks. The total mercury (THg) concentrations ranged from 0.82 to 6.98 ng·L −1 , and non-parametric pairwise multiple comparisons of the THg concentrations among the three different water samples showed that the THg concentrations were comparable. The total methylmercury (TMeHg) concentrations ranged from 0.041 to 0.115 ng·L −1 , and non-parametric pairwise multiple comparisons of the TMeHg concentrations showed a significant difference. Both the THg and MeHg concentrations of water samples from the ZQB were comparable to those of other remote areas, indicating that Hg concentrations in the ZQB watershed are equivalent to the global background level. Particulate Hg was the predominant form of Hg in all runoff samples, and was significantly correlated with the total suspended particle (TSP) and not correlated with the dissolved organic carbon (DOC) concentration. The distribution of mercury in the wetland water differed from that of the other water samples. THg exhibited a significant correlation with DOC as well as TMeHg, whereas neither THg nor TMeHg was associated with TSP. Based on the above findings and the results from previous work, we propose a conceptual model illustrating the four Hg distribution zones in glacierized environments. We highlight that wetlands may enhance the potential hazards of Hg released from melting glaciers, making them a vital zone for investigating the environmental effects of Hg in glacierized environments and beyond. [ABSTRACT FROM AUTHOR]