Article
Geochemistry & Geophysics
Wen-Hsuan Liao, Helene Planquette, Brivaela Moriceau, Christophe Lambert, Floriane Desprez de Gesincourt, Emmanuel Laurenceau-Cornec, Geraldine Sarthou, Thomas Gorgues
Summary: Sediments are usually considered to have limited influence on the dissolved iron (dFe) pool in the ocean, but recent observations and experiments suggest that iron released from suspended sediment particles can fertilize large areas of the ocean. In this study, dissolution experiments were conducted to measure the amount of dFe released from two types of resuspended sediments (silicate and calcite-rich) at different temperatures. The results showed that temperature influenced the dissolution of iron, but not manganese. Scavenging of iron and complexation with ligands were found to be important factors in both the release and fractionation of iron isotopes at the sediment-water boundary.
GEOCHIMICA ET COSMOCHIMICA ACTA
(2023)
Article
Geochemistry & Geophysics
Jacob P. Warner, Kristine L. DeLong, David Chicoine, Kaustubh Thirumalai, C. Fred T. Andrus
Summary: The coastline of Peru lacks long-lived marine organisms useful for paleoclimatic reconstructions, leading to a need for novel archives. Short-lived bivalves such as the surf clam Donax obesulus, commonly found in northern Peru, may serve as a paleoclimate archive despite vulnerabilities to temperature fluctuations. By isolating temperature-dependent variables, a paleotemperature equation for D. obesulus delta O-18 has been developed, showing potential for reconstructing ENSO-related climatic variations in the region and may have broader applications in understanding shell delta O-18 in other locations.
Article
Geochemistry & Geophysics
Huanting Hu, Benjamin H. Passey, Sophie B. Lehmann, Naomi E. Levin, Beverly J. Johnson
Summary: The O-18/O-16 ratios of biominerals are influenced by various factors, including regional climate, local hydrology, and behavioral and physiological factors. The addition of O-17 allows for further resolution of these factors. The study presents a triple oxygen isotope mass balance model and evaluates it against data from modern and fossil animals. The model predicts that animals in arid environments have wider ranges and lower minimum values of body water Delta'O-17, and leaf water consumers are more sensitive to relative humidity variations.
Article
Geochemistry & Geophysics
Danielle P. Santiago Ramos, Sune G. Nielsen, Laurence A. Coogan, Peter P. Scheuermann, William E. Seyfried Jr, John A. Higgins
Summary: High-temperature hydrothermal alteration of oceanic crust is an important source of potassium in the oceans, but its impact on potassium isotopic composition is not well understood. This study analyzes stable potassium isotope measurements in globally distributed high-temperature hydrothermal fluids and finds a strong correlation between potassium isotopes and Mg/K ratios. The variability in potassium isotopic composition can be explained mostly by high-temperature fluid-rock potassium exchange.
GEOCHIMICA ET COSMOCHIMICA ACTA
(2022)
Article
Ecology
Giedre Motuzaite Matuzeviciute, Basira Mir-Makhamad, Robert N. Spengler
Summary: This paper presents a study on the morphology of ancient cereal grains in Central Asia, focusing on data from the Chap site in Kyrgyzstan. It shows an increase in average size of grains over time, suggesting the evolution of larger grains or the introduction of larger variants. The study also discusses the potential influences of external factors on the formation of genetic varieties.
FRONTIERS IN ECOLOGY AND EVOLUTION
(2021)
Article
Geochemistry & Geophysics
Courtney Holden, T. Kurtis Kyser, Fred J. Longstaffe, Yuxiang Wang, John M. Casselman
Summary: The stable isotope compositions of otoliths can provide thermal histories of fish. This study focused on catadromous species, the American eel, and developed an isotopic fractionation equation to determine its thermal history in freshwater. The results showed that otolith growth can be decoupled from body growth, and the equation accurately predicted water temperature for the otoliths. This study has important implications for understanding the thermal history of wild eels.
Article
Engineering, Environmental
Yuanjie LI, Shuai Ren, Shiwei Zhang, Xingchi Jiang, Chin Pan
Summary: Bubble characteristics are crucial for understanding two-phase flow dynamics and simulation. This study compared bubble characteristics in subcooled flow boiling of artificial seawater with that of de-ionized water, finding differences in bubble size distributions and foam flow structure. The results suggest that the bubble characteristics in artificial seawater are different from those in de-ionized water, with the foam flow structure in artificial seawater being comparatively rigid.
CHEMICAL ENGINEERING JOURNAL
(2022)
Article
Ecology
Felix P. Leiva, Jeroen G. J. Boerrigter, Wilco C. E. P. Verberk
Summary: The size of an animal's body is closely related to its key ecological traits, such as fecundity, mortality, and growth. Ectothermic animals mature at smaller body sizes in warmer conditions and low oxygen availability (hypoxia). It is poorly understood whether these responses are due to changes in cell size and cell number, and how these cellular responses help ectotherms cope with heat and hypoxia.
FUNCTIONAL ECOLOGY
(2023)
Article
Geochemistry & Geophysics
Barbara Kleine, Andri Stefansson, Robert A. Zierenberg, Heejin Jeon, Martin J. Whitehouse, Kristjan Jonasson, Gudmundur O. Fridleifsson, Tobias B. Weisenberger
Summary: The study of natural anhydrite and pyrite from Mid-Atlantic ridge near Iceland reveals that key variables controlling anhydrite formation and sulfate recycling in the oceanic crust are influenced by the isotope composition of the source fluid, extent of water-rock interaction, temperature, and redox conditions. Hydrothermal anhydrite and pyrite exhibit specific delta S-34 and delta O-18 values, which indicate the processes of anhydrite formation and sulfur recycling in the oceanic crust.
GEOCHIMICA ET COSMOCHIMICA ACTA
(2022)
Article
Geochemistry & Geophysics
Jochem Baan, Meisha Holloway-Phillips, Daniel B. Nelson, Ansgar Kahmen
Summary: Variation in plant organic compound 82H and 818O values among species is common, but the extent to which this is driven by leaf water or biochemical isotope effects is unclear. Comparing leaf water and organic compound isotope values across 192 species, we found that variation in leaf water values may not strongly drive the variation in organic compound values.
GEOCHIMICA ET COSMOCHIMICA ACTA
(2023)
Article
Engineering, Environmental
Duk-Min Kim, Oh-Hun Kwon, Youn Soo Oh, Jin-Soo Lee
Summary: This study used isotopic signatures of sulfate and water to reveal different sources and processes in the groundwater system near the abandoned Seoseong mine in South Korea. The main issues include arsenic contamination, sulfate sources, seawater intrusion, and fertilizer contamination, which can be addressed through isotope analysis.
ENVIRONMENTAL GEOCHEMISTRY AND HEALTH
(2021)
Article
Forestry
Janez Kermavnar, Tom Levanic, Lado Kutnar
Summary: This study investigated the effects of different cutting intensities and local topographic and soil conditions on the composition of stable carbon and oxygen isotopes in wood of young beech trees. The results showed that the carbon isotope increased with cutting intensity, and the oxygen isotope was influenced by climatic variations and soil depth. These findings have implications for the future climate change impact on beech-dominated forests in the Dinaric Mountains.
FOREST ECOLOGY AND MANAGEMENT
(2023)
Article
Environmental Sciences
Hunter Roose, Gordon Paterson, Michael G. Frisk, Robert M. Cerrato, Paul Nitschke, Jill A. Olin
Summary: Mercury concentrations in Tilefish from the NW Atlantic Ocean were analyzed, with <2% of individuals over 70 cm exceeding USEPA guidelines for human consumption. Different mercury exposure and assimilation kinetics were observed in Tilefish stocks from different regions, indicating broad geographic variability in mercury bioaccumulation.
ENVIRONMENTAL POLLUTION
(2021)
Article
Geosciences, Multidisciplinary
Dongjie Tang, Xuewu Fu, Xiaoying Shi, Limin Zhou, Wang Zheng, Chao Li, Dongtao Xu, Xiqiang Zhou, Baozeng Xie, Xiyan Zhu, Ganqing Jiang
Summary: This study examines an oxygenation event that occurred around 1.57 billion years ago in the Gaoyuzhuang Formation of North China. The data analysis suggests that the event was likely caused by enhanced weathering of intermediate to mafic rocks, leading to increased phosphorus influx to the ocean and a rise in oxygen levels.
GEOPHYSICAL RESEARCH LETTERS
(2022)
Article
Chemistry, Multidisciplinary
Yeseul Kim, TaeKeun Rho, Dong-Jin Kang
Summary: This study investigated the quasi-meridional distribution of oxygen isotopes and salinity in the western Indian Ocean to understand water mass mixing. Results showed distinct mixing lines in different water layers based on the relationship between isotopes and salinity, and estimated the contribution of different water masses using a conservative mixing model. The study identified major water masses and their fractions based on latitude and depth in the study region.
Article
Biochemical Research Methods
Andrew C. Smith, Steve Welsh, Helen Atkinson, David Harris, Melanie J. Leng
Summary: This paper presents a new automated gas chromatography, pyrolysis/combustion, isotope ratio mass spectrometry (IRMS) system for dual isotope ratio analysis of methane (carbon and hydrogen) at ambient atmospheric concentrations. The system offers high precision, stable operation, and rapid sample processing, providing convenience for methane analysis in environmental studies.
RAPID COMMUNICATIONS IN MASS SPECTROMETRY
(2021)
Article
Multidisciplinary Sciences
Thomas W. Wong Hearing, Alexandre Pohl, Mark Williams, Yannick Donnadieu, Thomas H. P. Harvey, Christopher R. Scotese, Pierre Sepulchre, Alain Franc, Thijs R. A. Vandenbroucke
Summary: Contrasting hypotheses regarding Cambrian continental configuration and climate were tested, with results indicating that the Antarctocentric paleogeographic paradigm can reconcile geological data and simulated Cambrian climate. Analysis suggests a greenhouse climate during the Cambrian animal radiation period.
NATURE COMMUNICATIONS
(2021)
Article
Oceanography
Dharma Reyes-Macaya, Babette Hoogakker, Gema Martinez-Mendez, Pedro J. Llanillo, Patricia Grasse, Mahyar Mohtadi, Alan Mix, Melanie J. Leng, Ulrich Struck, Daniel C. McCorkle, Macarena Troncoso, Eugenia M. Gayo, Carina B. Lange, Laura Farias, Wilson Carhuapoma, Michelle Graco, Marcela Cornejo-D'Ottone, Ricardo De Pol Holz, Camila Fernandez, Diego Narvaez, Cristian A. Vargas, Francisco Garcia-Araya, Dierk Hebbeln
Summary: In this study, stable isotopes and other measurements were used to characterize the water masses in the Southeast Pacific. The results showed that stable isotopes of oxygen and deuterium can differentiate between different water masses, while dissolved inorganic carbon can provide further differentiation. The study also highlighted differences between the coastal and oceanic sections in terms of water mass characteristics.
JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS
(2022)
Article
Geosciences, Multidisciplinary
Sonja Felder, Takuya Sagawa, Mervyn Greaves, Melanie J. Leng, Ken Ikehara, Katsunori Kimoto, Siro Hasegawa, Thomas Wagner, Andrew C. G. Henderson
Summary: This study highlights the importance of understanding the palaeoceanography of the Japan Sea (JS) in analyzing the mid-Pleistocene transition (MPT). Through the analysis of sediments from IODP Site U1427, the study reveals that the δO-18 values in the JS vary during different stages of the MPT, indicating changes in the connection between the JS and adjacent ocean.
PALEOCEANOGRAPHY AND PALEOCLIMATOLOGY
(2022)
Article
Geosciences, Multidisciplinary
Savannah Worne, George E. A. Swann, Sev Kender, Jack H. Lacey, Melanie J. Leng
Summary: This study investigates the role of nutrient cycling on the subarctic Pacific biological pump during the Mid-Pleistocene Transition (MPT). The results show that during and after the 900 kyr event, the high productivity green belt zone in the Bering Sea upwelling region was characterized by low silicic acid utilization but high supply, coincident with the dominance of diatom resting spores. It is suggested that suppressed nutrient upwelling and enhanced opal remineralization caused an increase in silicic acid supply, but the net efficiency of the Bering Sea biological pump was sustained by preferential preservation of diatom resting spores and increased iron supply from expanded sea ice.
PALEOCEANOGRAPHY AND PALEOCLIMATOLOGY
(2022)
Article
Anatomy & Morphology
Peter B. Batson, Yuta Tamberg, Paul D. Taylor
Summary: This study used micro-computed tomography and scanning electron microscopy to investigate the zooidal budding in Horneridae from the initial bud. The results revealed two distinct budding modes, frontal autozooids budding from a multizooidal lamina and lateral autozooids budding from discrete abfrontal budding loci by exomural budding. These two budding modes integrate during primary branch morphogenesis, forming bilaminate branches. The findings provide insights for the taxonomy and phylogeny of Cancellata.
JOURNAL OF MORPHOLOGY
(2022)
Article
Zoology
Andrei Grischenko, Dennis P. Gordon, Paul D. Taylor, Piotr Kuklinski, Nina Denisenko, Mary E. Spencer-Jones, Andrew N. Ostrovsky
Summary: This study describes twenty-four recent species of the boreal-Arctic and Pacific cheilostome bryozoan genus Rhamphostomella. The taxonomic revision, morphology, ecology, zoogeography, and identification keys of these species are discussed. The diversity of Rhamphostomella peaks in the northwestern Pacific.
Article
Multidisciplinary Sciences
Sara B. Pruss, Lexie Leeser, Emily F. Smith, Andrey Yu Zhuravlev, Paul D. Taylor
Summary: A study reports a possible earliest occurrence of palaeostomate bryozoan fossils, providing further evidence for the early Cambrian roots of Bryozoa. These fossils show similarities to known bryozoans and exhibit characteristics of early bryozoans.
Article
Paleontology
Mali H. Ramsfjell, Paul D. Taylor, Emanuela Di Martino
Summary: This study describes three new species of the cheilostome bryozoan genus Microporella from the early Miocene in New Zealand, as well as the ovicells of another fossil species. These findings contribute to the understanding of the classification and evolution of Microporella.
Article
Environmental Sciences
Jessica C. A. Baker, Bruno B. L. Cintra, Manuel Gloor, Arnoud Boom, David Neill, Santiago Clerici, Melanie J. Leng, Gerhard Helle, Roel J. W. Brienen
Summary: Changes in the Amazon hydrological cycle have significant implications for the world's largest tropical forest and its biodiversity. However, the lack of long-term climate data in the region hinders our understanding of recent changes in Amazon hydrology. In this study, researchers analyze tree-ring oxygen isotope chronologies to shed light on hydrological changes in the Amazon over the past two centuries. The results reveal a strong correlation between tree-ring oxygen isotope records and interannual variation in Amazon River discharge and upwind precipitation. The findings suggest that rising sea surface temperatures in the North Atlantic may be the main driver behind the long-term increase in tree-ring oxygen isotope values, while recent decades have seen a reversal of this trend due to the strengthening of the Amazon hydrological cycle.
JOURNAL OF GEOPHYSICAL RESEARCH-BIOGEOSCIENCES
(2022)
Article
Environmental Sciences
J. E. Hatton, H. C. Ng, L. Meire, E. M. S. Woodward, M. J. Leng, C. D. Coath, A. Stuart-Lee, T. Wang, A. L. Annett, K. R. Hendry
Summary: Glaciers and ice sheets are rapidly warming due to climate change, and research suggests that glacial meltwaters provide important nutrients to downstream ecosystems. However, the fate of these nutrients in fjord environments is still uncertain. A study in southwest Greenland used concentration data and isotopic compositions to investigate silicon cycling in two contrasting fjords. The results suggest that glacially derived amorphous silica may play a role in modifying coastal waters within fjords.
JOURNAL OF GEOPHYSICAL RESEARCH-BIOGEOSCIENCES
(2023)
Editorial Material
Biology
Mark Williams
PHYSICS OF LIFE REVIEWS
(2023)
Article
Paleontology
Mark Williams, Reinhold Leinfelder, Anthony D. Barnosky, Martin J. Head, Francine M. G. McCarthy, Alejandro Cearreta, Stephen Himson, Rachael Holmes, Colin N. Waters, Jan Zalasiewicz, Simon Turner, Mary McGann, Elizabeth A. Hadly, M. Allison Stegner, Paul Michael Pilkington, Jerome Kaiser, Juan Carlos Berrio, Ian P. Wilkinson, Jens Zinke, Kristine L. Delong
Summary: This article examines three distinctive biostratigraphic signatures of humans associated with hunting and gathering, landscape domestication, and globalization. These signatures have significant fossil records that can be correlated inter-regionally, helping to describe the pattern of human expansion and resource appropriation. The study also shows that species translocations in the late stages of globalization can be used to build a palaeontological correlation network with decadal or sub-decadal precision, which reflects accelerating species extinction and a state shift in the biosphere in the twentieth century.
Article
Geosciences, Multidisciplinary
Andrew L. A. Johnson, Annemarie M. Valentine, Bernd R. Schoene, Melanie J. Leng, Stijn Goolaerts
Summary: Oxygen isotope sclerochronology is a useful method for reconstructing seasonal seafloor temperature range. By analyzing δO-1(8) data from bivalves in the southern North Sea basin, it was found that the current range is slightly smaller compared to the late Pliocene. Surface temperature was higher than seafloor temperature during summer, resulting in a greater seasonal range.
CLIMATE OF THE PAST
(2022)
Article
Biology
Anna McGairy, Toshifumi Komatsu, Mark Williams, Thomas H. P. Harvey, C. Giles Miller, Phong Duc Nguyen, Julien Legrand, Toshihiro Yamada, David J. Siveter, Harrison Bush, Christopher P. Stocker
Summary: Ostracod crustaceans began occupying marginal marine and estuarine environments early on, acting as a significant component in the transition from marine to non-marine environments.