Article
Environmental Sciences
Tatiparthi Srinivas, Soniya Sukumaran, K. Ramesh Babu
Summary: Stable isotopic methods are used to study food webs and quantify carbon sources in animal diets. This study focused on four abundant amphipod species in the Vashishti estuary and found that seasonal variations significantly affected isotopic values of organic matter, but not of individual amphipod species. The differences in isotopic values between amphipod species indicated species-specific diets, and the mixing model showed discrepancies in seasonal food preferences. The trophic level values of all amphipod species varied seasonally, with lower values after the monsoon, possibly due to anthropogenic nitrogen input.
ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH
(2022)
Article
Multidisciplinary Sciences
Shay T. Mullineaux, Berit Kostka, Luc Rock, Neil Ogle, Nikki J. Marks, Rory Doherty, Chris Harrod, W. Ian Montgomery, D. Michael Scantlebury
Summary: Isotopic techniques are widely used in geological, environmental, and ecological sciences to study energy and nutrient pathways. Isoscapes interpolate isotopic values and can reveal ecological shifts and distribution thresholds. This study demonstrates the application of soil isoscapes to understand trophic ecology variation in Eurasian badgers at a regional scale, showing the effectiveness of soil isoscapes in reducing biases and elucidating variations in macroscale isotopic studies.
SCIENTIFIC REPORTS
(2022)
Article
Limnology
Christopher B. Wall, Natalie J. Wallsgrove, Ruth D. Gates, Brian N. Popp
Summary: Compound-specific isotope analyses (CSIA) and multivariate isotope fingerprinting were used to track biosynthetic sources and reveal trophic interactions in a marine symbiosis study of reef coral (Montipora capitata) and Symbiodiniaceae algae. Results showed overlap in essential amino acid carbon and nitrogen isotopes between hosts and symbionts, with a high correlation between trophic nitrogen isotopes and plankton end-members indicating trophic connections and dietary sources.
LIMNOLOGY AND OCEANOGRAPHY
(2021)
Article
Marine & Freshwater Biology
Adriana Velasquez-Vacca, Jeffrey A. Seminoff, T. Todd Jones, George H. Balazs, Luis Cardona
Summary: This study analyzed stable isotope ratios in the epidermis and skeletal elements of Hawaiian green turtles to reconstruct their diet histories. The results showed that green turtles along the Kona/Kohala coast had an omnivorous diet, while those from Oahu had an herbivorous diet. The analysis also highlighted the limitations of using bone stable isotope ratios to assess green turtle diet.
Article
Ecology
Xusheng Gong, Zhiyan Xu, Qiutong Peng, Yuqing Tian, Yang Hu, Zhongqiang Li, Tao Hao
Summary: The study found that the δ13C and δ15N values of aquatic macrophytes in the arid zone of northwestern China were relatively enriched compared to terrestrial plants, with submerged plants > floating-leaved plants > emergent plants in terms of average δ13C values. Additionally, δ13C values of foliar were only negatively associated with precipitation, while δ15N values were mainly associated with temperature, precipitation, and potential evapotranspiration, indicating that water-related factors determine the δ13C values of macrophytes in the arid zone, and a combination of water and energy factors affect the δ15N values.
ECOLOGY AND EVOLUTION
(2021)
Article
Environmental Sciences
Andrey N. Reshetnikov, Daniil I. Korobushkin
Summary: Isotopic signatures of carbon and nitrogen are widely used for analyzing food web structures in aquatic ecosystems. The study highlights the importance of considering the effects of different tissues, storage methods, and preservation on isotopic values in animals. Different tissues of tadpoles and postmetamorphic juveniles may vary in isotopic composition.
Article
Multidisciplinary Sciences
Anna E. Poslednik, Thomas G. Evans, James Jackson, Anthony VanDeValk, Thomas Brooking, Lars Rudstam
Summary: Gut content analyses show that round gobies are highly dependent on dreissenid mussels, but stable isotope analysis often suggests a lower contribution of dreissenids. To test this, round gobies were collected from Oneida Lake and raised under different diets. The results indicate that the importance of dreissenid mussels may be underestimated in stable isotope studies.
Article
Biochemical Research Methods
Sabrina Riveron, Vincent Raoult, David J. Slip, Robert G. Harcourt
Summary: This study assessed the effects of lipid extraction on sulfur isotopes in marine ecosystems. The results showed that lipid extraction had minimal effect on shark muscle and pinniped skin, but significantly affected shark liver tissue. This could be due to the selective removal of sulfolipids and glutathione, which are present in higher concentrations in the liver.
RAPID COMMUNICATIONS IN MASS SPECTROMETRY
(2022)
Article
Limnology
Cecilia E. Heuvel, Yingming Zhao, Jan J. H. Ciborowski, Li Wang, Emilee Mancini, Aaron T. Fisk
Summary: The use of baselines in stable isotope studies is essential for interpreting food web structure. This study tested this assumption in Lake Erie by quantifying spatial variation in stable isotopes and density of benthic organisms. The results showed distinct spatial trends in stable isotopes, which were not related to population densities.
LIMNOLOGY AND OCEANOGRAPHY
(2023)
Article
Ecology
Cecilia Elizabeth Heuvel, Yingming Zhao, Aaron Thomas Fisk
Summary: Establishing a baseline for stable isotope studies is crucial for interpreting trophic relationships. Freshwater ecosystems face challenges in quantifying baseline stable isotopes due to difficulties in collecting representative samples. This study assessed temporal and spatial variation in stable isotopes in Lake Erie to understand the mechanism behind baseline stable isotope dynamics. The findings suggest that seasonal changes in system processes and plankton community dynamics influence stable isotopes in Lake Erie.
FRESHWATER BIOLOGY
(2023)
Article
Geochemistry & Geophysics
Peter M. J. Douglas, Emerald Stratigopoulos, Sanga Park, Benjamin Keenan
Summary: This study analyzed the isotopic composition of soil, stream and lake sediments, and aquatic plants and algae in a temperate forest lake catchment in Quebec. The results showed spatial differentiation in the sources of organic matter in sediments, with preferential deposition of terrestrial plant, aquatic plant, phytoplankton, and soil microbial biomass. The isotopic composition of sediments also varied with water depth, with shallow sediments characterized by plant-derived organic matter and deep sediments characterized by phytoplankton-derived organic matter. Downstream sediments had a greater input of aged microbial biomass from soils.
Article
Environmental Sciences
Miriam Gross-Schmoelders, Kristy Klein, Axel Birkholz, Jens Leifeld, Christine Alewell
Summary: Research shows that the hydrological characteristics of peatlands can affect the structure and metabolic processes of microbial communities, consequently influencing the variations in stable isotopes. Specifically, stable isotopes, especially delta N-15 values, can reflect the impact of drainage and rewetting on microbial metabolic processes. Therefore, stable isotope measurements provide valuable information on the success of drainage and restoration efforts in peatlands.
FRONTIERS IN ENVIRONMENTAL SCIENCE
(2021)
Article
Environmental Sciences
Sudhakaran Mani, S. Avudainayagam, K. Boomiraj, N. Sethupathi
Summary: The research found that organic management improved soil organic carbon content, nutrient levels, and enzyme activities, enhancing soil quality by increasing delta N-15 and decreasing delta C-13. Stable delta N-15 and delta C-13 isotopes serve as good indicators for monitoring soil health and carbon-nitrogen biogeochemical cycles in higher altitude agricultural soils.
GEOMICROBIOLOGY JOURNAL
(2021)
Article
Biodiversity Conservation
Keith A. Hobson, Tomohiro Kuwae, Mark C. Drever, Wendy E. Easton, Robert W. Elner
Summary: This study used isotopic mixing models to investigate the importance of biofilm as a nutritional source for migrating shorebirds in the Fraser River estuary. The results show that assimilated nutrients from biofilm contribute significantly to the protein and energy budgets of staging western sandpipers and dunlins. Furthermore, the study highlights the need for further isotopic research to better understand biofilm use by migratory shorebirds and its implications for conservation.
CONSERVATION PHYSIOLOGY
(2022)
Article
Astronomy & Astrophysics
Kaitlyn. A. A. McCain, Nozomi Matsuda, Ming-Chang Liu, Kevin. D. D. McKeegan, Akira Yamaguchi, Makoto Kimura, Naotaka Tomioka, Motoo Ito, Naoya Imae, Masayuki Uesugi, Naoki Shirai, Takuji Ohigashi, Richard. C. C. Greenwood, Kentaro Uesugi, Aiko Nakato, Kasumi Yogata, Hayato Yuzawa, Yu Kodama, Kaori Hirahara, Ikuya Sakurai, Ikuo Okada, Yuzuru Karouji, Satoru Nakazawa, Tatsuaki Okada, Takanao Saiki, Satoshi Tanaka, Fuyuto Terui, Makoto Yoshikawa, Akiko Miyazaki, Masahiro Nishimura, Toru Yada, Masanao Abe, Tomohiro Usui, Sei-ichiro Watanabe, Yuichi Tsuda
Summary: Samples from asteroid Ryugu returned by the Hayabusa2 mission provide evidence for aqueous fluid alteration related to CI chondrites. Investigations of the isotopic compositions of carbonate and magnetite in two Ryugu particles reveal that the fluid was initially between 0 and 20 degrees C and evolved towards lighter carbon and oxygen isotopic compositions as alteration proceeded. The ages of carbonate indicate that this fluid-rock interaction occurred within the first 1.8 million years of Solar System history, suggesting early accretion in a planetesimal less than 20 km in diameter or within a disrupted and reassembled larger body.
Article
Geography, Physical
Biljana Narancic, Emilie Saulnier-Talbot, Hanno Meyer, Reinhard Pienitz
Summary: Sedimentary diatoms have been utilized for quantitatively reconstructing climate variables, while the diatom oxygen isotopes can reflect past climatic and hydrological conditions. This study revealed a cooling trend in Nettilling Lake during the Late-Holocene, with diatom-inferred temperature and diatom-isotope values showing both increasing and decreasing trends that are linked to climatic conditions and meltwater inflows. The combination of proxies can help disentangle temperature and hydrological effects for paleoclimatic reconstructions and provide insights into postglacial environmental changes in northern lakes.
JOURNAL OF QUATERNARY SCIENCE
(2022)
Article
Limnology
Kathleen R. Stoof-Leichsenring, Sichao Huang, Sisi Liu, Weihan Jia, Kai Li, Xingqi Liu, Luidmila A. Pestryakova, Ulrike Herzschuh
Summary: Arctic and alpine aquatic ecosystems are undergoing rapid changes due to global warming, posing a threat to water resources. Macrophytes, playing a crucial role in freshwater ecology, have been poorly studied in terms of long-term diversity and environmental changes, mainly due to the limited presence of macrofossils in sediments. In this study, metabarcoding using the trnL P6 loop marker was employed to analyze macrophyte diversity in surface-sediment samples from arctic Siberian and alpine Chinese lakes. The results showed that macrophyte richness and composition are primarily influenced by temperature and conductivity. Furthermore, the study revealed minor compositional turnover in Siberian cores during the Late Pleistocene/Holocene, whereas a significant shift from emergent to submerged taxa was observed in the Tibetan alpine core.
LIMNOLOGY AND OCEANOGRAPHY
(2022)
Article
Geography, Physical
Stefan Lauterbach, Michael Strasser, Kerstin Kowarik, Hans Reschreiter, Gerhard W. Mandl, Christoph Spotl, Birgit Plessen, Achim Brauer
Summary: The underground salt mining complex of Hallstatt in Austria is renowned for its cultural importance and archaeological artifacts. However, the impact of natural hazards on the prehistoric mining community is still poorly understood. By investigating sediment cores from nearby Lake Hallstatt, researchers identified three large-scale mass movement events that occurred in the mid-19th and late 9th century CE, as well as the mid-4th century BCE, shedding light on the occurrence of such events in the vicinity of the salt mines throughout history.
JOURNAL OF QUATERNARY SCIENCE
(2023)
Article
Geology
Georg Schwamborn, Lutz Schirrmeister, Ali Mohammadi, Hanno Meyer, Andrei Kartoziia, Flavio Maggioni, Jens Strauss
Summary: This study investigates the sediment core from the Lena River delta to reconstruct the river history and understand the changes in landscape and carbon sequestration. The analysis includes grain-size measurement, mineral analysis, permafrost formation reconstruction, and assessment of organic carbon. The results show a transition from high energy to low energy regime after the Last Glacial Maximum, and the river re-routing and refreeze of the underlying river talik in the early Holocene. This may be caused by internal dynamics or tectonic movement in the Lena River lowland.
Article
Geography, Physical
Wanyi Zhang, Steffen Mischke, Dominic Hosner, Chengjun Zhang, Birgit Plessen, Huwei Li, Xiaojing Zhang
Summary: The late glacial and Holocene sediment record from Lake Heihai in the Kunlun-Pass region reveals cold and dry conditions between approximately 12.9 and 12.3 cal ka BP, followed by higher temperatures. Warmer and wetter conditions with increased lake levels and decreased lake-water salinity occurred from approximately 10.8 to 7.0 cal ka BP, attributed to the strengthening of the summer monsoon. From approximately 7.0 to 1.2 cal ka BP, a decline in lake level and an increase in lake-water salinity suggested cold and dry conditions, with glacier advances in the catchment.
QUATERNARY INTERNATIONAL
(2023)
Article
Environmental Sciences
Izabella Baisheva, Luidmila Pestryakova, Sardana Levina, Ramesh Glueckler, Boris K. Biskaborn, Stuart A. Vyse, Birgit Heim, Ulrike Herzschuh, Kathleen R. Stoof-Leichsenring
Summary: The livelihoods of local communities in Central Yakutia, Siberia, depend on the alaas landscapes and lakes. The development and dynamics of these lakes are closely linked to climate change, permafrost thawing, catchment conditions, and land use. By analyzing sedimentary ancient DNA and biogeochemistry from Lake Satagay, researchers reconstructed the lake's development over the past 10,800 years. The findings suggest that the lake formation occurred earlier than previously believed, and changes in diatom and macrophyte communities were driven by climate-driven shifts in water level and mineral and organic input. The study also highlights the potential impact of future warming and anthropogenic land use on the desiccation of the lake. Rating: 9/10
JOURNAL OF PALEOLIMNOLOGY
(2023)
Article
Multidisciplinary Sciences
Heike. H. H. Zimmermann, Kathleen. R. R. Stoof-Leichsenring, Viktor Dinkel, Lars Harms, Luise Schulte, Marc-Thorsten Huett, Dirk Nuernberg, Ralf Tiedemann, Ulrike Herzschuh
Summary: The disappearance of sea ice has caused significant changes in polar marine ecosystems over the past 20,000 years, as revealed by ancient DNA analysis of marine sediments off Kamchatka. The shift from a late-glacial ecosystem adapted to sea ice to an ice-free Holocene ecosystem is characterized by changes in dominant organisms. This study highlights the importance of ancient DNA in studying long-term ecosystem responses to climate change for improved risk assessment in ocean and cryosphere.
NATURE COMMUNICATIONS
(2023)
Article
Geosciences, Multidisciplinary
Alexandra M. Zuhr, Sonja Wahl, Hans Christian Steen-Larsen, Maria Horhold, Hanno Meyer, Thomas Laepple
Summary: Stable water isotopic composition in firn and ice cores can provide valuable information on past climatic conditions, but the interpretation of isotopic variability requires a characterization of how the isotopic profile in the snow develops.
JOURNAL OF GEOPHYSICAL RESEARCH-EARTH SURFACE
(2023)
Article
Environmental Sciences
Stefan Kruse, Iuliia Shevtsova, Birgit Heim, Luidmila A. Pestryakova, Evgeniy S. Zakharov, Ulrike Herzschuh
Summary: The subarctic forest tundra transition zone is vulnerable to climate change, and forest changes could result in biodiversity loss. The impact of complex landscapes with barriers and channels for seed dispersal is understudied. This study uses a vegetation model to investigate potential tree above-ground biomass change in mountainous central Chukotka (Siberia). The results suggest densification of existing tree stands and a lagged forest expansion, but in scenarios with cooling after 2300 CE, forests gradually retreat to their pre-twenty-first-century position, leaving an imprint of forests in former tundra areas with potential negative impact on tundra biodiversity.
ARCTIC ANTARCTIC AND ALPINE RESEARCH
(2023)
Article
Ecology
Raphael Hebert, Laura Schild, Thomas Laepple, Ulrike Herzschuh
Summary: This study investigates the variability of vegetation composition and its patterns in the Holocene using a global fossil pollen dataset. The findings reveal increasing fluctuations in vegetation composition from centennial to millennial timescales and identify differences in variability between different biome classes. The results have important implications for understanding and assessing the impacts of future climate change on vegetation.
ECOLOGY AND EVOLUTION
(2023)
Article
Meteorology & Atmospheric Sciences
Shuting Zhai, William Swanson, Joseph R. Mcconnell, Nathan Chellman, Thomas Opel, Michael Sigl, Hanno Meyer, Xuan Wang, Lyatt Jaegle, Jochen Stutz, Jack E. Dibb, Koji Fujita, Becky Alexander
Summary: Snowpack emissions are an important source of gas-phase reactive bromine in the Arctic, and quantifying bromine emissions from snowpack is essential for the interpretation of ice-core bromine. Model simulations suggest that recycling of reactive bromine on the snow skin layer leads to a 9-17% loss of deposited bromine across all ice-core locations. The high-latitude coastal Akademii Nauk (AN) ice core from the Russian Arctic is most likely to preserve an atmospheric signal compared to Greenland ice cores.
JOURNAL OF GEOPHYSICAL RESEARCH-ATMOSPHERES
(2023)
Article
Environmental Sciences
Jens Fohlmeister, Marc Luetscher, Christoph Spoetl, Andrea Schroeder-Ritzrau, Birgit Schroeder, Norbert Frank, Rene Eichstaedter, Martin Truessel, Vanessa Skiba, Niklas Boers
Summary: This study examines speleothem records from caves in the European Alps and finds that solar insolation, as well as sea level change, played a significant role in modulating stadial-interstadial variability during the penultimate glacial period.
COMMUNICATIONS EARTH & ENVIRONMENT
(2023)
Article
Geosciences, Multidisciplinary
Hima. J. J. Hassenruck-Gudipati, Christoff Andermann, Sylvia Dee, Camilla. F. F. Brunello, Krishna Pyari Baidya, Dirk Sachse, Hanno Meyer, Niels Hovius
Summary: The Himalayan mountain range produces large rainfall gradients and the Indian Summer Monsoon contributes to most of the precipitation in the central Himalayas. However, the partitioning of moisture into different storage systems and their contribution to river discharge remains unclear. In this study, field data and stable isotope composition of river and rain water were used to understand hydrological variability. The study found that pre-ISM rainfall is distinct from monsoon rain and groundwater. The research highlights the importance of pre-ISM precipitation and groundwater as sources of river discharge in the central Himalayas.
Article
Geosciences, Multidisciplinary
Markus Czymzik, Rik Tjallingii, Birgit Plessen, Peter Feldens, Martin Theuerkauf, Matthias Moros, Markus J. Schwab, Carla K. M. Nantke, Silvia Pinkerneil, Achim Brauer, Helge W. Arz
Summary: Knowledge about Holocene environmental variability in the circum-Baltic region is crucial for understanding its responses to climate change. By analyzing sediments from Lake Kalksjon in Sweden, we found that the lake's productivity was higher during periods of warmer winters and a positive North Atlantic Oscillation (NAO) polarity. The NAO polarity may serve as a qualitative record of the lake's productivity over the past 9600 years.
CLIMATE OF THE PAST
(2023)
