Article
Environmental Sciences
Petr Vodicka, Kimitaka Kawamura, Jaroslav Schwarz, Vladimir Zdimal
Summary: This study systematically investigated the phase interactions between aerosol and gaseous carbon samples using seasonally resolved stable carbon isotope ratio values. It was found that despite different carbon sources in aerosols, the isotope differences remained similar between seasons.
SCIENCE OF THE TOTAL ENVIRONMENT
(2022)
Article
Environmental Sciences
Lei Ma, Wei Zhang, Xunhua Zheng, Zhisheng Yao, Han Zhang, Rui Wang, Bo Zhu, Kai Wang, Chunyan Liu, Guangmin Cao, Yanfen Wang, Yiping Zhang, Wenjun Zhou, Shijie Han, Junhui Zhang, Yinghong Wang
Summary: The study compared the DN and DN-CO2 methods for measuring N2O fluxes in alpine pastures, revealing that the DN method can lead to positive flux biases in certain situations, while showing no significant differences in others. By correcting the measurements from the DN method, the estimated annual N2O emissions from grasslands in China could be significantly reduced.
ATMOSPHERIC ENVIRONMENT
(2021)
Article
Energy & Fuels
Qiong Wang, Hao Xu, Dazhen Tang, Pengfei Ren
Summary: This study investigates the composition and formation mechanisms of coalbed gas (CBG) in the Miquan and Fukang areas of the southern Junggar Basin. It is found that there are significant differences in the CBG composition between the two areas. The CBG in the Fukang area is mainly methane, while the CBG in the Miquan area has a high CO2 concentration. The production pathways of biogas also differ between the two areas, with the Fukang area mainly using the CO2 reduction pathway and the Miquan area mainly using the acetic acid/methyl fermentation pathway. This study clarifies the fate of CO2 in the Miquan area and highlights the influence of exogenous CO2 on microbial methanogenic pathways.
Article
Biodiversity Conservation
Justin M. Mathias, Tara W. Hudiburg
Summary: The use of stable isotopes to understand plant physiological processes has become common in ecology. However, there is currently no standardized tool to calculate isotope-derived plant physiological indices. In response, we developed isocalcR, an R package that provides functions and reference data to simplify the use of stable isotope data in plant tissues.
GLOBAL CHANGE BIOLOGY
(2022)
Article
Biochemistry & Molecular Biology
Heesoo Jeong, Yan Yu, Henrik J. Johansson, Frank C. Schroeder, Janne Lehtio, Nathaniel M. Vacanti
Summary: Stable-isotope tracing is a method used to measure intracellular metabolic pathway utilization by feeding a cell system a stable-isotope-labeled tracer nutrient. An algorithm and tool, PolyMID-Correct, have been developed to computationally remove the influence of naturally occurring heavy isotopes, making the method more accurate and reliable. This algorithm is applicable to data collected on both low- and high-mass resolution mass spectrometers, and PolyMID-Correct is open source under an MIT license.
Article
Water Resources
Yihan Li, Jianmin Bian, Jialin Li, Yuxi Ma, Jesus Horacio Hernandez Auguiano
Summary: This study reveals the characteristics and process of water-rock interactions of natural mineral water in the Changbai Mountain area, China, using hydrochemical and isotopic data. The results show that rock weathering plays a leading role in the chemical composition of mineral water, which is controlled by the lithology and tectonic environment of the region. Feldspar, pyroxene, and olivine are the main factors influencing the mineral water chemistry. The results also suggest a certain delay in precipitation recharge and its significant impact on surface water resources.
JOURNAL OF HYDROLOGY-REGIONAL STUDIES
(2022)
Article
Environmental Sciences
Lei Wang, Cun-De Xiao, Zhi-Heng Du, Damien T. Maher, Jing-Feng Liu, Zhi-Qiang Wei
Summary: Inland waters serve as significant sources of greenhouse gases to the atmosphere, with high-altitude saline lakes on the Tibetan Plateau showing high CH4 concentrations as sources to the atmosphere but acting as sinks for CO2. Salinity, fDOM, temperature, and dissolved oxygen are key factors influencing CH4 and CO2 diffusive fluxes in these lakes, with a distinctly different isotopic source values of CO2 and CH4 found in Qinghai Lake and Hala Lake.
ADVANCES IN CLIMATE CHANGE RESEARCH
(2022)
Article
Chemistry, Analytical
Ying Zhang, Bei Gao, Luis Valdiviez, Chao Zhu, Tara Gallagher, Katrine Whiteson, Oliver Fiehn
Summary: Stable isotope tracers are commonly used with gas chromatography coupled to mass spectrometry for enzyme activity and metabolic pathway studies. In this research, three commercially available instruments were used to analyze samples from a stable isotope labeling study on Rothia mucilaginosa metabolism. The study found that all three GC-MS instruments can be used for stable isotope tracing studies, with high-resolution GC-QTOF MS offering additional capabilities in identifying the chemical structures of unknown compounds.
ANALYTICAL CHEMISTRY
(2021)
Article
Environmental Sciences
Bonan Li, Stephen P. Good, Richard P. Fiorella, Catherine E. Finkenbiner, Gabriel J. Bowen, David C. Noone, Christopher J. Still, William R. L. Anderegg
Summary: Stable isotope ratios of H, O, and C are informative of environmental exchanges, especially δ13C for latent heat flux under arid and low annual precipitation conditions. These stable isotope datasets collected by NEON contribute valuable information about bulk environmental fluxes useful for interpreting biogeochemical and ecohydrological processes.
ENVIRONMENTAL RESEARCH LETTERS
(2023)
Article
Plant Sciences
Yongsheng Wu, Zilong Liao, Xiangqian Yu, Yin Qiang, Wang Hui, Gao Li
Summary: This study used a hydrogen stable isotope technique to investigate the water use characteristics of four xerophytic shrubs. The results showed that under light rainfall, C. korshinskii and S. psammophila primarily used the 80-140 cm layer of soil water and groundwater, while A. ordosica and S. vulgaris increased their utilization of soil water. Under heavy rainfall, C. korshinskii and S. psammophila still used the deeper layers, while A. ordosica and S. vulgaris expanded their water utilization depth. Therefore, the combination of certain shrubs can help avoid competition in artificial sand-fixing vegetation systems.
FRONTIERS IN PLANT SCIENCE
(2023)
Article
Environmental Sciences
Chengcheng Xia, Yujie Liu, Yuchuan Meng, Guodong Liu, Xiaohua Huang, Yu Chen, Ke Chen
Summary: This study investigates the spatio-temporal evolution of water isotopes in the Qingbaijiang urban catchment in southwest China, based on 30 sampling campaigns on precipitation, river water, and groundwater. It quantitatively evaluates the seasonal groundwater-surface water interaction using isotope-aid hydrograph separation and estimates the young water fraction in river water at different locations. The study reveals the enrichment of stable isotopes in river water and groundwater from upstream to downstream, reflecting the change in dominant water source and the impact of evaporation.
Article
Geosciences, Multidisciplinary
Rosemary W. H. Carroll, Jeffrey Deems, Matthias Sprenger, Reed Maxwell, Wendy Brown, Alexander Newman, Curtis Beutler, Kenneth H. Williams
Summary: A hydrologic and snowpack stable water isotope model is used to assess the controls on isotopic inputs in a mountainous basin. The study finds that the most depleted isotopic conditions occur in the upper subalpine where snow accumulation is high and rainfall is low. The isotopic inputs in meltwater are determined by the amount, phase, and isotopic mass of precipitation during the ablation period. Evaporative loss from the snowpack has the greatest effect on d-excess in snowmelt above treeline and in regions with low vegetation shading.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Multidisciplinary Sciences
Yaguang Li, Xianhua Bai, Dachao Yuan, Chenyang Yu, Xingyuan San, Yunna Guo, Liqiang Zhang, Jinhua Ye
Summary: Cu-based high-entropy two-dimensional oxide is synthesized using a PVP templated method and shows enhanced sintering resistance and CO2 hydrogenation activity. It achieves a record photochemical energy conversion efficiency in photothermal CO2 hydrogenation under ambient sunlight irradiation.
NATURE COMMUNICATIONS
(2023)
Article
Geography, Physical
Tianjie Jin, Laiming Zhang, Katharine W. Huntington, Yixiong Wen, Andrew J. Schauer, Xue Gu, Chengshan Wang
Summary: The modern elevation of China varies from the Tibetan plateau in the west to sea level in the east, with several topographic steps. This study investigates the paleoenvironmental and paleoelevation changes in North China during the late Mesozoic using delta O-18, delta C-13, and clumped isotope values of paleosol carbonates. The results suggest that the Ordos Basin in western North China maintained a high paleoelevation during the Middle Jurassic-late Early Cretaceous, while the Hefei Basin in eastern North China experienced a significant elevation reduction by the Early Cretaceous. These findings indicate a topographic change that may have influenced paleoclimate patterns and caused a transition from dry to humid climate in eastern North China.
GLOBAL AND PLANETARY CHANGE
(2023)
Article
Environmental Sciences
Yang Tang, Ruiyin Han
Summary: Surface water samples from Maolan National Natural Reserved Park were analyzed for major ions and carbon, sulfur isotopes from September 2013 to June 2014. The results suggest that bicarbonate and sulfate are the main anions in the watershed, indicating an influence of rock weathering on water chemistry. Additionally, human activities have led to higher sulfate content in some sample sites.
Article
Plant Sciences
Arthur Gessler, Lukas Bachli, Elham Rouholahnejad Freund, Kerstin Treydte, Marcus Schaub, Matthias Haeni, Markus Weiler, Stefan Seeger, John Marshall, Christian Hug, Roman Zweifel, Frank Hagedorn, Andreas Rigling, Matthias Saurer, Katrin Meusburger
Summary: The study found that European beech mainly takes up water from the topsoil during the early stages of a drought, reduces water uptake as the drought progresses, and cannot compensate for the reduced topsoil water availability by additional uptake from deeper soil layers. After rewetting following a drought, beech can restore water uptake from the topsoil to pre-drought levels.
Article
Ecology
Sabrina Santos Pires, Barbara Herbstritt, Christine Stumpp, Markus Weiler, Michael Paul Stockinger
Summary: Water is essential for plant development, and understanding the plant-water relationship is crucial for ensuring food security and conserving ecosystems. Stable isotopes of water are widely used to study ecohydrological processes, such as root water uptake. However, obtaining water samples from plants for stable isotope analysis is laborious and challenging. In this study, the water-vapour equilibrium method was tested to determine stable water isotopes in different plant organs. The study found that cutting samples and equilibrating for 24 hours produced the most reliable isotope ratios. The results were consistent with current understanding of water isotopes in plants, demonstrating the feasibility of the chosen sample preparation method.
Article
Computer Science, Interdisciplinary Applications
Giuseppe Brunetti, Christine Stumpp, Jiri Simunek
Summary: This paper proposes a hybrid strategy, G-CLPSO, which combines global search properties with exploitation capability for solving optimization problems in hydrological modeling. The results from benchmark tests and synthetic modeling scenarios demonstrate that G-CLPSO outperforms other methods in terms of accuracy and convergence.
ENVIRONMENTAL MODELLING & SOFTWARE
(2022)
Article
Engineering, Civil
Devakunjari Vadibeler, Michael P. Stockinger, Leonard I. Wassenaar, Christine Stumpp
Summary: The experiments showed that the equilibration time for isotopic analysis of water in different textured soils and porewater saturation levels varies, with different optimal times for different soil types and saturation levels. The presence of organic carbon in soil also impacts the equilibration time needed for isotopic equilibrium to be reached, requiring longer times for soils with higher organic carbon content.
JOURNAL OF HYDROLOGY
(2022)
Article
Water Resources
Amelie Herzog, Kerstin Stahl, Veit Blauhut, Markus Weiler
Summary: The limited number of gauging stations hampers the understanding of the interaction between streamflow, groundwater, and water usage during drought. Non-commercial measurement devices can help overcome this lack of monitoring, but they need thorough testing. The Dreisam River in Germany provided a useful case study area for water quality and quantity monitoring.
HYDROLOGICAL PROCESSES
(2022)
Article
Agronomy
Gunther C. Liebhard, Andreas Klik, Christine Stumpp, Angela G. Morales Santos, Josef Eitzinger, Reinhard Nolz
Summary: This study investigated the weekly evaporation and transpiration rates in a soybean field under varying soil water conditions. The results showed that vertical soil water distribution and meteorological conditions influenced the transpiration/evaporation rates. During dry periods, evaporation was almost zero, while a wet surface layer increased evaporation.
INTERNATIONAL AGROPHYSICS
(2022)
Article
Chemistry, Inorganic & Nuclear
Paul Koeniger, Christine Stumpp, Axel Schmidt
Summary: River monitoring for tritium in Germany began in the early 1970s and now includes 50 stations and stable isotopes. The stable isotope time series show contributions of snow and ice melt in the Rhine and Danube rivers during summer months. Close to the northern coasts, stable isotope patterns reflect the influence of seawater and tides. Surprisingly, there were no extreme changes in stable isotope patterns during the dry season of 2018/2019, but rather an indication of enhanced groundwater contribution. Continual long-term data across different river basins of varying sizes and altitudes highlight the importance of a co-organized national network.
ISOTOPES IN ENVIRONMENTAL AND HEALTH STUDIES
(2022)
Article
Chemistry, Inorganic & Nuclear
Ioannis Matiatos, Luis Araguas-Araguas, Leonard Wassenaar, Lucilena Rebelo Monteiro, Astrid Harjung, Cedric Douence, Martin Kralik
Summary: Nitrate stable isotopes were measured to understand nitrate contamination and microbial cycling processes. In the Fischa-Dagnitz spring and river system in Austria, nitrate concentrations showed minor annual variance, while nitrate isotopes exhibited surprising variability. The isotopic composition helped differentiate between denitrified groundwater inputs and biochemical cycling processes, despite the stable nitrate concentration.
ISOTOPES IN ENVIRONMENTAL AND HEALTH STUDIES
(2023)
Article
Multidisciplinary Sciences
Leonard I. Wassenaar, Leonardo Sisti, Matthias Pilecky, Martin Kainz
Summary: Non-exchangeable hydrogen-isotope (62Hn) measurements are important in forensics for sample authenticity, traceability, and provenance determination. However, the measurements are often complicated due to uncontrolled exchangeable hydrogen and moisture contamination, leading to incomparability among laboratories. A revised technical solution (UniPrep2) is introduced to control hydrogen-isotope exchange and enable robust online sample drying and vapor equilibration. This solution empowers isotope analysts to conduct reproducible controlled vapor equilibrations and vacuum-oven evacuation with helium drying, providing accurate and precise 62Hn values for various organic sample types.
Article
Environmental Sciences
Marit van Tiel, Markus Weiler, Daphne Freudiger, Greta Moretti, Irene Kohn, Kai Gerlinger, Kerstin Stahl
Summary: Droughts can cause extreme low flow in rivers, impacting negatively on their ecosystems. Melting snow and ice in mountain water towers can help alleviate the hydrological consequences of drought, but global warming threatens this cryosphere. A study on the European river Rhine basin shows that low flow situations worsen in future conditions due to increased meteorological drought and glacier ice melt contributions. These findings are important for adaptation planning and are relevant for other river basins.
Article
Biochemical Research Methods
Leonard I. Wassenaar, Cedric Douence, Jodie Miller
Summary: This study evaluated the accuracy and precision of stable-isotope analyses of nitrate conducted by international laboratories. The majority of laboratories were able to accurately determine delta N-15 and delta O-18 results, but had difficulties in determining delta O-17.
RAPID COMMUNICATIONS IN MASS SPECTROMETRY
(2023)
Article
Soil Science
Gernot Bodner, Anna Zeiser, Katharina Keiblinger, Christoph Rosinger, Samuel Konrad Winkler, Christine Stumpp, Thomas Weninger
Summary: This study evaluates the restoration of soil pore characteristics in the transition towards soil-health oriented farming systems and identifies the factors shaping different pore domains. The results suggest that soil-health oriented pioneer farmers can effectively manage functionally relevant pore domains for climate change resilience by promoting biological agents of structure formation.
SOIL & TILLAGE RESEARCH
(2023)
Article
Environmental Sciences
Joschka Geissler, Lars Rathmann, Markus Weiler
Summary: Snow variability in forested environments is challenging to model due to its interactions with the environment. To better understand and validate snow models, reliable observation data at similar scales is required. This study presents a new extensive dataset of daily snow variability in a sub-alpine forest, Switzerland, obtained through a dense sensor network, high-resolution LiDAR data, and manual measurements. Machine learning algorithms are used to identify four spatial clusters with similar snow depth dynamics. By combining these clusters with observed snow depth time series, daily high-resolution maps of snow depth and snow water equivalent (SWE) are derived. These products are the first to provide continuous spatio-temporal snow depth and SWE based on field data.
WATER RESOURCES RESEARCH
(2023)
Article
Chemistry, Inorganic & Nuclear
David X. Soto, Luis J. Araguas-Araguas, Liang-Feng Han, Leonard I. Wassenaar
Summary: This study evaluated the impact of storage protocols on carbon isotopes in groundwater and found that using plastic sampling bottles for storage led to contamination and underestimated age estimations. In contrast, using glass bottles for storage can avoid contamination and maintain higher analytical precision.
ISOTOPES IN ENVIRONMENTAL AND HEALTH STUDIES
(2023)
Article
Water Resources
Ingo Haag, Julia Krumm, Dirk Aigner, Andreas Steinbrich, Markus Weiler
Summary: The distributed water balance model LARSIM has been improved by introducing an infiltration module to simulate infiltration excess, Horton Overland Flow (HOF), and pluvial floods due to intense rainfall. The introduced module has shown promising results in simulating intense rain events in different catchments, laying a foundation for future real-time forecasting of pluvial floods. However, uncertainties in radar-based rainfall estimation can cause disparities in discharge estimation, highlighting the need for further improvements in LARSIM and precipitation forecasting with weather radar.
HYDROLOGIE UND WASSERBEWIRTSCHAFTUNG
(2022)
