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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.

To investigate the seasonal variation of chemical weathering and its controlling factors in the central Tibetan Plateau (TP), hydrochemistry of stream water in two alpine catchments, the Niyaqu and Qugaqie, was studied at an unprecedented temporal resolution from July 2016 to September 2017. Chemical compositions of river water in the two catchments were dominated by Ca2+ and HCO 3 − . SO 4 2− in the stream water mainly derived from sulfide oxidation but sulfuric acid played a minor role in rock weathering compared with carbonic acid. The contributions of atmospheric input, silicate weathering, carbonate weathering and sulfide oxidation to riverine solutes of the Niyaqu, which overlies tuff, sandstone, shale, and carbonate and is mainly recharged by groundwater, were about 5%, 12%, 65%, and 18%, respectively; these contributions to dissolved loads of the Qugaqie, where lithology consists of granite and sandstone and nearly half the stream water originates from glaciers meltwater, were 10%, 35%, 34% and, 20%, respectively. Contribution of different sources to riverine solutes in the Niyaqu were almost invariant between different seasons, while the percentage of these sources in the stream water of the Qugaqie showed significant seasonal variations, especially for the weathering of silicate and carbonate: average value of the former increased from 29% in the monsoon season to 45% during the nonmonsoon period, on the contrary, average value of the latter decreased from 37% to 29% in the corresponding periods. Carbonate weathering rates (CWR) and silicate weathering rates (SWR) in the study areas exhibited distinct seasonal variability. During the monsoon season, the average CWR and SWR values in the Niyaqu were 34.3 t/km2/y and 6.8 t/km2/y, respectively, and their corresponding values in the Qugaqie were 16.7 t/km2/y and 11.0 t/km2/y, respectively, which means that the average value of CWR in the Niyaqu during the monsoon season is comparable with the CWR (average for one year) in catchments located in the eastern TP, and the SWR in the Qugaqie during the monsoon season is close to the SWR (average for one year) of some basins at the south slope of the Himalaya. Chemical denudation rates decreased sharply during the nonmonsoon period, indicating little chemical exhumation within that time due to cold and arid weather. Runoff was the most important factor that controls chemical weathering in both the Niyaqu and Qugaqie, followed by physical erosion rates, and the influence of temperature seems to be insignificant in the Niyaqu while at the same time crucial in the Qugaqie.

The aquifers on the Tibetan Plateau (TP) constitute as origin for major river systems, which are supplying millions of people all over Asia. Increasing population and tourism activities leading to larger water consumption. Hence, water supply is getting increasingly important. The TP is a sensitive system and is noticeable reacting climate change. Past decades are marked with, increasing trends of precipitation, melting of glaciers and degradation of permafrost and have generally lead to rising water levels in lakes on the TP. To ensure future water supply, aquifer characterisation and future prognosis on groundwater behavior are therefore necessary. However, due to the remote character of the TP, knowledge according to hydrogeological parameter is scarce. The aim of this study is therefore to estimate a range for aquifer parameter based on geophysical methods. The Zhagu basin, situated in the Nam Co Lake basin (second largest lake on the TP), is used as a case study. This project is part of the International Research Training Group “Geoecosystems in transition on the Tibetan Plateau” (TransTiP), funded by the DFG.During several field work campaign in July 2018, May 2019 and September 2019 disturbed sediment samples were taken and were analyzed for grain size distribution. Selected sediment layer in the laboratory were tested. Outcome of this analysis is the porosity for each selected sediment layer. Another measurement during field work has been conducted, namely electrical resistivity tomography measurements (ERT). To get better approximation of porosity and sediment characteristics, Archie’s Law is used as model to estimate those properties and later on to compare it to field and laboratory results. Two approaches are implemented (i) calculates the bulk resistivity based on known porosity from the laboratory and known conductivity of pore water measured during field work (ii) calculates the porosity with known conductivity of pore water and the bulk conductivity. For analysis saturated sediment layers were chosen.The investigation shows that both approaches are largely applicable and leading to almost same results and trends of each sediment layer. The best percentage deviation of the modeled bulk resistivity results to the measurement in the field could be achieved by position D11 which is situated near the Nam Co Lake showing a deviation of around 7%. Inside the catchment the percentage deviation is largely increasing. However, the application of Archie’s Law in combination with field and laboratory measurements allows to construct a porosity ranges for future groundwater flow calibration. In addition, the results emphasising the zonation of the subsurface in (un)saturated zones due to the small amount of resistivity.Sediment profiles, ERT measurements, observations, interpretation and conclusion including the comparison of simulated resistivity and simulated porosity to field resistivity and porosity based on laboratory analysis will be shown and discussed in the contribution.

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 6.98ng·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 0.115ng·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.

Very little data is available on chemical weathering and its controlling factors in small catchments of the central Tibetan Plateau (TP) despite being the main part of the plateau. Hydrochemistry of river water in 24 small catchments in the Nam Co basin draining different strata and recharge forms was investigated monthly during the 2018 monsoon season. The results show that carbonate dissolution is the most important geochemical process controlling the evolution of hydrochemistry of most river water in the Nam Co basin (the average contribution to riverine solutes reaches 46%) even though its contribution shows significant spatial distribution: low values occur in some granite regions (e.g. 27% in H10) but is high in catchments where carbonate rocks are prevalent (e.g. 68% in H23). The contribution of silicate weathering is low, with an average of 11% in catchments located on the east and south banks draining sandstone/mudstone, while this value increases to 32% in catchments on the south bank which pass through granite, and on the west bank. The contribution of sulfide oxidation in most rivers on the south bank is unexpectedly high (40%) but is much lower in other rivers (13%). This spatial difference is attributed to the influence of topography, particularly slope. The carbonate weathering rate (CWR) in small catchments of the Nam Co basin shows spatial heterogeneity and is significantly and positively correlated with the lithologic coefficient which proposed to indicate the degree of rock weatherability and negatively correlated with mean slope and mean altitude. The spatial distribution of the silicate weathering rate (SWR) is not as significant as the CWR and is mainly governed by runoff depth. Chemical weathering rates in the glacierised catchments are 1.3 times higher than those in the non-glacierised regions which share similar lithology. Thus, glaciation enhances chemical weathering in the study area. The area-weighted average value of CWR and SWR in the study area is 23.2 t/km2/y and 5.2 t/km2/y, respectively. Chemical weathering rates in the Nam Co basin, central TP are relatively low when compared with those in catchments located on the edge of the TP, indicating the carbon sequestration effect caused by this supergene geological process in this area may be insignificant.

The uplift of the Tibetan Plateau (TP) not only may enhance physical denudation and chemical weathering but also makes this area contain the largest glacier storage outside the polar regions. There is an argument on whether glaciation favours chemical weathering and carbon sequestration. To explore chemical weathering processes and intensities in the cold glacial region of the central TP, hydrochemistry of the river water in two catchments, i.e. the Qugaqiong and Qugaqie, was monitored from April to September 2018 with high-frequency sampling. These two catchments share similar geographical features except there are some cold glaciers in the upper reaches of the Qugaqie. The results of chemical composition show that the river water of the Qugaqie has a lower proportion of Ca2+ and HCO3− but higher SO42− and K++Na+ compared with the Qugaqiong. The seasonal variation of ionic concentration in the Qugaqie is significant but minor in the Qugaqiong. Those differences highlight the glacial impact in the Qugaqie compared with the non-glacierized Qugaqiong. Solutes in the glacial runoff of the Qugaqie mainly derive from sulfide oxidation. Its contribution to cations in the runoff of the Zhadang glacier and the Hanging glacier reaches 39% and 36%. The second most important contribution is carbonate dissolution (32% for both glacial runoffs). Silicate weathering provides fewer solutes and its contribution is only 20% and 11% in the two glacial runoffs, respectively. River water of the Qugaqiong shares similar hydrochemical characteristics with the non-glacial tributaries draining granodiorite/biotite adamellite in the Qugaqie. The contribution of sulfide oxidation to solutes in those rivers decreases to 10% while carbonate dissolution increases to 50%. Glacial comminution exposed trace sulfide minerals, thus made sulfide oxidation became pretty active due to this reaction is much faster than other mineral dissolution. The carbonate weathering rate (CWR) and silicate weathering rate (SWR) in the Qugaqie catchment are 9.7 t/km2/y and 6.7 t/km2/y. In comparison, values in the Qugaqiong catchment are 6.9 t/km2/y and 3.8 t/km2/y, respectively, which means CWR and SWR is 1.4 and 1.8 times higher in the Qugaqie catchment, respectively. Higher runoff and physical erosion rates are considered as the main reasons for higher chemical denudation rates in the Qugaqie catchment. The drainage system of the glaciers is dominated by the distributed pattern, which caused longer residences time of water, thus further promoted chemical weathering in the glacierized region. Our observation supports the idea that glaciation in the glacierized catchment of the central TP enhances chemical weathering, especially for SWR. Chemical denudation rates in the Qugaqie catchment remain at a moderate level compared with other glacierized catchments in the world and lithology and runoff are important factors to cause this spatial heterogeneity.

The Tibetan Plateau (TP) is a focus of chemical weathering research worldwide. However, scant studies on the northern flank of the Himalayas and the vast inland region of the TP hinders understanding of the role the TP has played in the global carbon cycle. The upstream and midstream of the Yarlung Tsangpo (UMRYT) is the longest river in Tibet with the highest elevation in the world. Two sampling campaigns were conducted in December 2012 and August 2013 to estimate the intensity of chemical weathering, CO2 consumption rates, and their controlling factors in the UMRYT basin. Results show that the total dissolved cations and anions have a broad range of changes with an average of 199 mg/L (46–637 mg/L) in December and 196 mg/L (43–523 mg/L) in August. This parameter displays small seasonal variations for most sampling sites; these are just slightly diluted in August even though runoff is 6–12 times higher than that in December. The evidence from TZ+⁎/HCO3−⁎ (⁎indicates after deduction from atmospheric inputs) demonstrates the proportion of rock weathering caused by H2SO4 is surprisingly high in the sub-basins to the extent that it is generally above 50% in both seasons. Dogxung Tsangpo, Nianchu River, and the small tributaries at the southern bank are severely affected by rock weathering involving sulfuric acid (above 90%). The chemical budget shows that the average proportion of TZ+ in river water derives from atmospheric inputs, weathering of silicate, carbonate, and evaporite are 9%, 19%, 50%, and 22%, respectively. The contribution of carbonate dissolution to TZ+ is 8–16% higher during the monsoon season. In contrast, the proportions of silicate weathering and evaporite dissolution are 4–16% and 1–8% larger in the non-monsoon period, respectively. Chemical weathering intensity shows significant spatial differences. Carbonate weathering rates (CWR) and silicate weathering rates (SWR) in the main tributaries vary from 12.6 ± 4.8 to 20.0 ± 5.8 t/km2/y and from 2.9 to 5.6 t/km2/y, respectively. Lithology exerts a profound influence on the spatial heterogeneity of CWR in basins of the main tributaries of the UMRYT, while the spatial distribution of SWR is mainly governed by runoff. The CWR and SWR in the whole basin are 13.2 ± 4.0 t/km2/y and 3.9 t/km2/y, respectively, indicating the chemical weathering intensity and its CO2 sequestration are much lower than most large rivers draining the Tibetan Plateau and other orogenic belts around the world.

A novel algorithm for fast resolution of multicomponent overlapping nuclear magnetic resonance (NMR) spectrum using the wavelet compression and the immune algorithm (IA) is proposed. Taking advantage of the linear property of the wavelet transform (WT), the overlapping NMR spectrum (antigen) can be compressed by WT before it is input into the immune network, the antibodies are also compressed to the same scheme. After extraction of the compressed information of each component, the resolved NMR spectra can be restored by the WT reconstruction. It was proven that the result is almost the same with the result from an IA, but the calculation speed is much faster.

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.

This study is aimed at detecting diatom in lung, liver and kidney tissues using PCR - DHPLC technology after different periods of enzyme digestion to assess the effect of enzyme digestion on the detection of diatom species. Twenty Randomly selected experimental rabbits were drowned at the same place. Their liver, kidney, and lung tissues were removed for sampling. After the extraction of DNA from the samples, amplification was conducted with specific primers of the SSU gene of diatom. Then, an analysis was performed with agarose gel electrophoresis and DHPLC. Within 2 h-8 h, the amount of the diatom species found in the lung gradually increased over time and was statistically significant. After 8 h, with enzyme digestion, the amount of the diatom species found in lung showed no significant increase (). However, as for the liver and kidney, within 2h-6h, the amount of the diatom species gradually increased over time and was statistically significant. After 6h, the fig. did not present significant growth (). The amount of the diatom species found in the organs after different periods of digestion time had significant differences, which provides a reference for the detection of diatoms and also, has a good application prospect in the forensic identification of drowning.

Energy spectra of 500 keV–1MeV He+ ion penetrating 50 μ m – 100 μ m thick seed coat of maize, fruit peel of grape and of tomato, are measured. The results indicate that these thick biological targets, as seen by the penetrating ions, are inhomogeneous, and there are open paths, along which the incident ions can penetrate the targets easily. While most of the incident ions are stopped in the targets, some of the penetrating ions only lose a small fraction of their initial incident energy. The penetration energy spectra show a pure electronic stopping feature. Transmission electron microscope (TEM) micrographs taken from these samples with thickness of 30 μ m indicate that 150 keV electron beam from the TEM can penetrate the thick samples to give very good images with clear contrast. The electronic structures of β−1,4 glucosan molecular chains, which is deemed as the most important constituent of the cell walls of seed coats and peels of fruits, are calculated to show the possible open-path directions which exist in biological samples.