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Dissolved zinc in the western Bering Sea and near Kamchatka Strait: A coastal source and transport to the subarctic Pacific Mar. Chem. (IF 3.0) Pub Date : 2024-03-12 Kuo Hong Wong, Hajime Obata, Taejin Kim, Hirofumi Tazoe, Asami S. Mashio, Hiroshi Hasegawa, Jun Nishioka
Dissolved zinc (dZn) is an important micronutrient for phytoplankton in the ocean. In high nutrient low chlorophyll (HNLC) regions like the western Bering Sea basin, Zn deficiency might induce shifts in phytoplankton community species. In this study, we presented the first dZn distribution data in the western Bering Sea and near Kamchatka Strait and investigated the biogeochemical cycles of Zn in these
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Low-blank method for the offline batch analysis of the low concentration of dissolved lead in natural waters and its application to natural waters, including the tropical Northwest Pacific Ocean Mar. Chem. (IF 3.0) Pub Date : 2024-03-12 Shuo Jiang, Jing Zhang, Zheng Bo Liu, Han Su
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A half-cell reaction approach for pH calculation using a solid-state chloride ion-selective electrode with a hydrogen ion-selective ion-sensitive field effect transistor Mar. Chem. (IF 3.0) Pub Date : 2024-03-09 S. Fisher Gonski, George W. Luther III, Amanda L. Kelley, Todd R. Martz, Elliott G. Roberts, Xinyu Li, Bo Dong, Jordan A. Watson, Taylor S. Wirth, Najid Hussain, Randy J. Feris Serrano, Edward Hale, Wei-Jun Cai
Here, we explicitly define a half-cell reaction approach for pH calculation using the electrode couple comprised of the solid-state chloride ion-selective electrode (Cl-ISE) as the reference electrode and the hydrogen ion-selective ion-sensitive field effect transistor (ISFET) of the Honeywell Durafet as the hydrogen ion -sensitive measuring or working electrode. This new approach splits and isolates
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Distributions of zirconium, hafnium, and niobium in the Indian Ocean: Influence of lithogenic sources on incompatible elements Mar. Chem. (IF 3.0) Pub Date : 2024-02-23 Ryuta Ueki, Linjie Zheng, Shotaro Takano, Yoshiki Sohrin
Zirconium (Zr), hafnium (Hf), and niobium (Nb) are incompatible elements concentrated on the granitic continent. They are trace elements at the pmol/kg level in seawater and are considered potential tracers for water masses. However, data on the distribution of the three elements in modern oceans are limited, particularly in the Indian Ocean. Here, we report the first basin-scale sectional distributions
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Dynamic distribution and photochemical-microbial coupling degradation of dissolved organic matter in a large river-Influenced Bay Mar. Chem. (IF 3.0) Pub Date : 2024-02-23 Mingzheng Zhang, Xinke Wang, Shengkang Liang, Haoyang Ma, Yanqun Yang, Hongguan Li, Shanshan Li, Xihua Yu
A large river-influenced offshore area is the junction where land and open sea meet, which is important in the biogeochemical processes of dissolved organic matter (DOM). Because hydrodynamic and biogeochemical processes are complex, processes such as the photochemical and microbial degradation of DOM are poorly understood. In this study, to further understand the degradation mechanisms of DOM from
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On-chip label-free sorting and enrichment of microplastic particles by using deterministic lateral displacement Mar. Chem. (IF 3.0) Pub Date : 2024-02-18 Kai Zhao, Jianhong Dong, Dejian Kong, Junzhu Yao, Yiming Yao, Junsheng Wang
A novel deterministic lateral displacement (DLD) method employing a pressure-driven flow for the continuous size-based separation of microplastic particles is presented in this paper. To induce the DLD effect, arrays of triangular posts were designed to enhance the sorting resolution and reduce the particles clogging. For the particles with a diameter larger than the critical diameter () in the DLD
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Detection of impurities in m-cresol purple with Soft Independent Modeling of Class Analogy for the quality control of spectrophotometric pH measurements in seawater Mar. Chem. (IF 3.0) Pub Date : 2024-02-03 Michael B. Fong, Yuichiro Takeshita, Regina A. Easley, Jason F. Waters
Accurate spectrophotometric pH measurements in seawater are critical to documenting long-term changes in ocean acidity and carbon chemistry, and for calibration of autonomous pH sensors. The recent development of purified indicator dyes greatly improved the accuracy of spectrophotometric pH measurements by removing interfering impurities that cause biases in pH that can grow over the seawater pH range
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Trace and rare earth element systematics of cold-seep carbonates from the Krishna-Godavari basin: A comparison between isotopically distinct carbonate deposits Mar. Chem. (IF 3.0) Pub Date : 2024-02-02 Muralidhar Kocherla, Durbar Ray, M. Satyanarayanan, H.M. João, Christo Sojan
Mineralogical and isotopically distinct authigenic carbonates from the zones of methane oxidation and methanogenesis in the cold-seep environment, from the Krishna-Godavari basin are investigated for major, trace, and rare earth element compositions. For this study, the elemental compositions of the C-depleted carbonate phase (δC < −45‰) developed under the influence of anaerobic methane oxidation
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Exploration of the nitrification process in surface sediment of a hypereutrophic intertidal zone via hydroxylamine monitoring Mar. Chem. (IF 3.0) Pub Date : 2024-01-16 Ami Natori, Yuuki Sanada, Shogo Sugahara, Seiichi Nohara, Yasushi Seike, Yukiko Senga
Hydroxylamine is considered an indicator of nitrification, as it is both produced and consumed during the ammonium (NH4+) oxidation process. In this study, to explore the site of active nitrification and elucidate the factors controlling nitrification, hydroxylamine concentrations in the seawater and porewater of the hypereutrophic Yatsu tidal flat, eastern Japan, were measured using the iodine oxidation
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Regeneration of sedimentary phosphorus and iron in a large seasonally hypoxic estuary deciphered by 224Ra/228Th disequilibria Mar. Chem. (IF 3.0) Pub Date : 2024-01-17 Zhongliang Lin, Yilin Cheng, Ergang Lian, Tong Wu, Lin Wei, Xiangming Shi, Xinyu Jiang, Liuting Yuan, Shouye Yang, Pinghe Cai
Using a 224Ra/228Th disequilibrium approach, we demonstrate in this study that benthic fluxes of dissolved inorganic phosphorus (DIP) in the seasonally hypoxic Yangtze River Estuary were largely manipulated by two counteracting processes: the decomposition of sedimentary organic matter and adsorption of DIP onto iron (Fe) oxides. The decomposition rate of sedimentary organic matter rose exponentially
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Biogeochemical evidence of flow re-entrainment on the main fringing reef of La Reunion Island Mar. Chem. (IF 3.0) Pub Date : 2024-01-08 Elsa Lagoutte, Aline Tribollet, Sophie Bureau, Emmanuel Cordier, Perrine Mangion, Anne Chauvin, Pascal Mouquet, Lionel Bigot, Patrick Frouin, Pascale Cuet
Understanding factors influencing seawater chemistry variability in coral reef environments is a major challenge to improve predictions of their evolution in the context of ocean acidification. In this study, autonomous sensors for current speed and direction, photosynthetically active radiation (PAR), temperature, salinity, dissolved oxygen (DO) and pHT were deployed three times between 2021 and 2022
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Nitrogen and carbon cycling and relationships to radium behavior in porewater and surface water: Insight from a dry year sampling in a hypersaline estuary Mar. Chem. (IF 3.0) Pub Date : 2024-01-05 Dorina Murgulet, Cody V. Lopez, Audrey R. Douglas, Mustafa Eissa, Kousik Das
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Recommendations for best practice for iron speciation by competitive ligand exchange adsorptive cathodic stripping voltammetry with salicylaldoxime Mar. Chem. (IF 3.0) Pub Date : 2024-01-03 Léo Mahieu, Dario Omanović, Hannah Whitby, Kristen N. Buck, Salvatore Caprara, Pascal Salaün
The method of competitive ligand exchange followed by adsorptive cathodic stripping voltammetry (CLE-AdCSV) allows for the determination of dissolved iron (DFe) organic speciation parameters, i.e., ligand concentration (LFe) and conditional stability constant (log KFe′Lcond). Investigation of DFe organic speciation by CLE-AdCSV has been conducted in a wide range of marine systems, but aspects of its
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Muddy sediments are an important potential source of silicon in coastal and continental margin zones Mar. Chem. (IF 3.0) Pub Date : 2024-01-03 Dongdong Zhu, Su Mei Liu, Aude Leynaert, Paul Tréguer, Jingling Ren, Jonas Schoelynck, Yuwei Ma, Jill N. Sutton
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Tracing anthropogenic aerosol trace metal sources in the North Atlantic Ocean using Pb, Zn and Ni isotopes Mar. Chem. (IF 3.0) Pub Date : 2023-12-10 Xingchao Zhang, Nolwenn Lemaitre, Jörg Dominik Rickli, Tim Jesper Suhrhoff, Rachel Shelley, Ali Benhra, Saliou Faye, Mohamed Ahmed Jeyid, Derek Vance
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Speciation, distribution and relationship of zinc and cadmium in summer coastal seawater of northern China Mar. Chem. (IF 3.0) Pub Date : 2023-12-15 Yan Liang, Dawei Pan, Hong Wei, Haitao Han, Ying Li, Tianzhuo Liu
Considering that zinc (Zn) is essential for marine phytoplankton growth and cadmium (Cd) can replace Zn as a cofactor of mutual conversion and regulate the effect of carbonic anhydrase, we here presented the concentration, chemical speciation and relationship of Zn and Cd collected from three consecutive voyages (2019–2021) in summer coastal seawater of northern China. Dissolved Zn and Cd concentrations
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Carbon and silica fluxes during a declining North Atlantic spring bloom as part of the EXPORTS program Mar. Chem. (IF 3.0) Pub Date : 2023-12-12 Samantha J. Clevenger, Claudia R. Benitez-Nelson, Montserrat Roca-Martí, Wokil Bam, Margaret Estapa, Jennifer A. Kenyon, Steven Pike, Laure Resplandy, Abigale Wyatt, Ken O. Buesseler
The goal of NASA's EXport Processes in the Ocean from RemoTe Sensing (EXPORTS) project is to develop a predictive understanding of the fate of global ocean primary productivity and export of carbon from the surface to the deep ocean. Thorium-234 (234Th, t1/2 = 24.1 d) was used to measure sinking particle export from an anticyclonic eddy during the EXPORTS North Atlantic cruise (May 2021) at the Porcupine
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Contrasting rare earth element concentrations and mixing behaviors in the St. Lawrence Estuary and Saguenay Fjord Mar. Chem. (IF 3.0) Pub Date : 2023-11-25 Zoya Qudsi, Alfonso O. Mucci, Huy Dang, Yves Gélinas, Gwénaëlle Chaillou
Rare earth elements (REEs) including Yttrium (Y) are commonly used as tracers of estuarine and oceanic mixing. The lanthanide series and yttrium are usually referred to as REYs. The geochemical behavior of REYs in estuarine environments is generally described as being non-conservative, with large-scale removal by particle scavenging. During mixing, partitioning of these elements occurs according to
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Production and preservation of organic carbon in sub-seafloor tephra layers Mar. Chem. (IF 3.0) Pub Date : 2023-11-23 Jack Longman, Hayley R. Manners, Thomas M. Gernon, James McManus, Martin R. Palmer, Steven J. Rowland, Paul A. Sutton
The deposition of volcanic ash into the ocean initiates a range of chemical and biological reactions. During diagenesis, these reactions may enhance the preservation of organic carbon (OC) in marine sediments, which ultimately promotes CO2 sequestration from the ocean-atmosphere system. However, this interpretation is reliant on a small number of studies that make a link between tephra and OC burial
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Contrasting optical properties of dissolved organic matter between oceanic regions near the Getz and Dotson ice shelves in the Amundsen Sea, West Antarctica Mar. Chem. (IF 3.0) Pub Date : 2023-11-23 Juyoung Son, Jinyoung Jung, Youngju Lee, Tae-Wan Kim, Jisoo Park, Mi Hae Jeon, Mi Ok Park
The Amundsen Sea, located in West Antarctica, is experiencing rapid melting due to the intrusion of Circumpolar Deep Water, which is causing ice sheet thinning and basal melting. The resulting changes can affect the biogeochemical cycle of dissolved organic matter (DOM) by supplying iron from sea ice and/or glacier, thereby influencing primary production and ocean circulation. Therefore, it is crucial
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Dynamics of nitrous oxide and methane in the southeastern Arabian Sea Mar. Chem. (IF 3.0) Pub Date : 2023-11-18 K.S. Arya, T.R. Gireeshkumar, E.R. Vignesh, K.R. Muraleedharan, K.U. Abdul Jaleel, M.A. Abdul Razaque, C.M. Furtado, V. Sudheesh, T.M. Balakrishnan Nair, K.S. Krishnamohan
This study examined the factors controlling the intra- and inter-seasonal variations of dissolved methane (CH4) and nitrous oxide (N2O) in the southeastern Arabian Sea (SEAS). Time-series measurements of CH4, N2O and allied biogeochemical parameters were carried out during the monthly campaigns in the coastal waters and a seasonal campaign in the shelf waters of the SEAS. The southwest monsoon period
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Autonomous high-frequency time-series observations of total alkalinity in dynamic estuarine waters Mar. Chem. (IF 3.0) Pub Date : 2023-11-07 Li Qiu, Mario Esposito, María Martínez-Cabanas, Eric P. Achterberg, Quanlong Li
Total alkalinity (TA) is a variable that reflects the acid buffering capacity of seawater, and is key to studies of the global carbon cycle. Daily and seasonal TA variations are poorly constrained due to limitations in observational techniques, and this hampers our understanding of the carbonate system. High quality and high temporal resolution TA observations are required to constrain the controlling
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Comparing the isotopic and molecular composition of dissolved organic carbon between the oligotrophic South China Sea and the adjacent North Pacific Ocean: Signals of biodegradation, conservative mixing, and terrestrial input Mar. Chem. (IF 3.0) Pub Date : 2023-11-04 Peng Jiang, Hongmei Chen, Zhanfei Liu, Xiaolin Li
The cycling of oceanic dissolved organic carbon (DOC) is a crucial component of the global carbon cycle, yet the identification of sources and the mechanisms of its molecular transformation remain poorly understood. This study compared the isotopic and molecular composition of DOC between the oligotrophic South China Sea (SCS) and the adjacent North Pacific Ocean (NPO), and traced both its allochthonous
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Variability in zinc:phosphorous and zinc:silicon ratios and zinc isotope fractionation in Southern Ocean diatoms: Observations from laboratory and field experiments Mar. Chem. (IF 3.0) Pub Date : 2023-10-31 Robin Grun, Moneesha Samanta, Michael J. Ellwood
We studied the impact of iron limitation on zinc uptake and the zinc isotope (δZn) composition for Southern Ocean phytoplankton. We undertook laboratory culture and field incubation experiments, and linked these to depth profiles of dissolved (dZn) and particulate (pZn) zinc collected from three sites in the Southern Ocean. For the laboratory experiments, diatom growth rates, cellular zinc accumulation
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Dynamics of chromophoric dissolved organic matter in a highly productive Amundsen Sea polynya Mar. Chem. (IF 3.0) Pub Date : 2023-10-30 Ji Hu, Siyou Xue, Jun Zhao, Zhengbing Han, Dong Li, Haifeng Zhang, Peisong Yu, Minhui Zheng, Jianming Pan, Yongge Sun
Dissolved organic carbon (DOC) is the largest organic carbon pool in the ocean, and is the most active component in respect to the ocean carbon cycling. However, its study in Antarctica has been limited due to challenges associated with sample collection. In this study, we conduct an investigation on the chromophoric dissolved organic matter (CDOM) in a highly productive Amundsen Sea Polynya (ASP)
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Comparison of methods to determine extraction efficiencies of Ra isotopes and 227Ac from large volume seawater samples Mar. Chem. (IF 3.0) Pub Date : 2023-10-19 Morgane Léon, Pieter van Beek, Virginie Sanial, Marc Souhaut, Paul Henderson, Matthew A. Charette
Radium isotopes, other than 226Ra, and 227Ac are typically present at low activities in the open ocean. The analysis of these isotopes thus requires the collection of large volumes of seawater and high sensitivity, low background instruments. To obtain the required large volumes (hundreds to thousands of liters), these radionuclides are typically preconcentrated on cartridge-style filters impregnated
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Lithium isotope systematics and water/rock interactions in a shallow-water hydrothermal system at Milos Island, Greece Mar. Chem. (IF 3.0) Pub Date : 2023-10-11 U-Tat Lou, Shein-Fu Wu, Chen-Feng You, Chuan-Hsiung Chung, Eugenia Valsami-Jones, Emmanuel Baltatzis
The active venting fluids of Milos Island, located within the southern Aegean Sea, belong to a shallow-water hydrothermal system (< 200 m depth) that shows chemical compositions and evolution processes comparable to those of mid-ocean ridges (MOR). In this study, we analyze Li and δLi in 69 vent water samples, grouped into two types based on their salt content. The low-Cl end-member (EM) Cave fluids
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Macronutrient biogeochemistry in Antarctic land-fast sea ice: Insights from a circumpolar data compilation Mar. Chem. (IF 3.0) Pub Date : 2023-10-07 Sian F. Henley, Stefano Cozzi, François Fripiat, Delphine Lannuzel, Daiki Nomura, David N. Thomas, Klaus M. Meiners, Martin Vancoppenolle, Kevin Arrigo, Jacqueline Stefels, Maria van Leeuwe, Sebastien Moreau, Elizabeth M. Jones, Agneta Fransson, Melissa Chierici, Bruno Delille
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Thermochemical decomposition reveals distinct variability of sedimentary organic carbon reactivity along the Yangtze River estuary-shelf continuum Mar. Chem. (IF 3.0) Pub Date : 2023-10-06 Wanhua Huang, Huiyuan Yang, Songfan He, Bin Zhao, Xingqian Cui
Continental shelves host 90% of annual organic carbon (OC) deposition in the global ocean and are regarded as “hot spots” of carbon burial and decomposition. Numerous studies have thus investigated OC sources, recent accumulation, long term preservation and key processes involved. Nonetheless, OC reactivity or lability, as a key property governing the fate of OC in the long term, received less attention
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Sources and behaviors of particulate organic carbon, iron, and manganese in the bottom nepheloid layer of the southwestern East Sea (Japan Sea) Mar. Chem. (IF 3.0) Pub Date : 2023-10-02 Junhyeong Seo, Guebuem Kim, Hojong Seo, Taehee Na, Suyun Noh, Jeomshik Hwang
The sources and behaviors of particulate organic carbon (POC) and particulate iron and manganese (pFe and pMn, respectively) in the bottom nepheloid layer (or benthic nepheloid layer, BNL) of the southwestern East Sea, also known as the Japan Sea, along a transect from the shelf to the central Ulleung Basin were investigated. The fluxes of POC, pFe, and pMn from the BNL to the seafloor on the shelf
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Particulate organic carbon export fluxes estimates by 234Th[sbnd]238U disequilibrium in the oxygen minimum zone off the Peruvian coast Mar. Chem. (IF 3.0) Pub Date : 2023-09-30 Wokil Bam, Beat Gasser, Kanchan Maiti, Isabelle Levy, Juan Carlos Miquel, Roberta L. Hansman, Jan Scholten, Ruifang C. Xie, Stefan Sommer, Rainer Kiko, Peter W. Swarzenski
The Peruvian upwelling zone is one of the most productive marine ecosystems in the world with a spectacular, pronounced oxygen minimum zone (OMZ). Globally OMZs are increasing in size and intensity with far-reaching consequences for the marine biological carbon pump and carbon export; thus, these zones need to be carefully monitored to be able to understand future climate change impacts. The current
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Spatial and temporal variation of dissolved iodine in the eastern Arabian Sea Mar. Chem. (IF 3.0) Pub Date : 2023-09-29 Adnan Shaikh, Siby Kurian, Damodar M. Shenoy, Anil K. Pratihary, Albertina B. Dais, Richita Naik, Sidhesh G. Borker
Here we report the seasonal and spatial variation of iodide (I) and total dissolved iodine (TI) along a transect covering the oxygen minimum zone (OMZ) in the Arabian Sea (AS). This data is generated after a gap of more than two decades since the US-Joint Global Ocean Flux Study (JGOFS) reported observations of iodine speciation in the region. Also, this is the first study to report on iodine speciation
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New insights on black carbon in pelagic Atlantic sediments Mar. Chem. (IF 3.0) Pub Date : 2023-09-12 Kari St.Laurent, Mark Cantwell, Rainer Lohmann
Black carbon (BC) is ubiquitous in pelagic sediments and presumed to have an older radiocarbon age due to long ocean residence times and pre-aging in terrestrial soils. Here, we analyzed sediments from five regions in the subtropical Atlantic Ocean to quantify the black carbon fraction of the total organic carbon pool. Black carbon, derived from the chemothermal oxidation method, comprised between
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Ocean acidification reduces iodide production by the marine diatom Chaetoceros sp. (CCMP 1690) Mar. Chem. (IF 3.0) Pub Date : 2023-09-09 Ergün Bey, Claire Hughes, Karen Hogg, Rosie Chance, Katherina Petrou
Phytoplankton in marine surface waters play a key role in the global iodine cycle. The biologically-mediated iodide production under future scenarios is limited. Here we compare growth, iodate to iodide conversion rate and membrane permeability in the diatom sp. (CCMP 1690) grown under seawater carbonate chemistry conditions projected for 2100 (1000 ppm) and pre-industrial (280 ppm) conditions. We
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Anthropogenic carbon estimation in the surface ocean from atmospheric CO2 fugacity at the BATS (Bermuda Atlantic Time-series Study) station Mar. Chem. (IF 3.0) Pub Date : 2023-08-28 Ben Hadid Nadia, Touratier Franck, Guglielmi Véronique, Mouakher Amira, Goyet Catherine
In surface seawater, it is usually very difficult to quantify anthropogenic carbon concentrations. Many processes (such as air-sea exchanges of gases and heat, biological activity, and mixing of water masses), are at play and often on different timescales. Thus, various hypotheses are used to estimate the anthropogenic concentrations in surface waters. Here, using the relatively long (1980s to present)
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Regulated vs. unregulated rivers: Impacts on CDOM dynamics in the eastern James Bay Mar. Chem. (IF 3.0) Pub Date : 2023-08-22 Amélie Évrard, Caroline Fink-Mercier, Virginie Galindo, Urs Neumeier, Michel Gosselin, Huixiang Xie
The eastern James Bay (EJB) coast harbors numerous rivers, but there is a dearth of knowledge concerning dissolved organic matter (DOM) in the downstream coastal water. Here we report a four-year (2018–2021) and multi-seasons field study on the mixing behavior and characteristics of the chromophoric DOM (CDOM) in the nearshore EJB. Freshwater discharged from the extensively regulated La Grande River
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Method development and quantification of all B vitamins and selected biosynthetic precursors in winter and spring samples from the North Sea and de novo synthesized by Vibrio campbellii Mar. Chem. (IF 3.0) Pub Date : 2023-08-22 Stefan Bruns, Gerrit Wienhausen, Barbara Scholz-Böttcher, Simone Heyen, Heinz Wilkes
The simultaneous analysis of B vitamins and biosynthetic precursors in seawater is of great interest as it gives a better insight into the fluctuations of their availability for marine organisms and thus allows us to better understand the nature of interactions between prototrophic and auxotrophic organisms. The analysis of these micronutrients is challenging, as they are usually present in the marine
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Distributions of humic substances in an estuarine region (Otsuchi Bay, Japan) determined using electrochemical and optical methods Mar. Chem. (IF 3.0) Pub Date : 2023-08-09 Ying Ping Lee, Kuo Hong Wong, Hajime Obata, Keisuke Nishitani, Hiroshi Ogawa, Hideki Fukuda, Chia-Jung Lu
Humic substances are major components of the dissolved organic carbon pool in aquatic environments that can bind to trace metals like copper and iron as organic ligands. The unique chromophoric and fluorescence properties of humic substances enabled measurements using conventional optical methods but recently a new electrochemical method using cathodic stripping voltammetry has emerged. In this study
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Links between regional and depth patterns of microbial communities and enzyme activities in the western North Atlantic Ocean Mar. Chem. (IF 3.0) Pub Date : 2023-08-03 C. Chad Lloyd, Sarah Brown, John Paul Balmonte, Adrienne Hoarfrost, Sherif Ghobrial, Carol Arnosti
Heterotrophic bacteria process much of the organic matter produced by phytoplankton in the ocean. A large proportion of this organic matter is in the form of polysaccharides, structurally complex, high molecular weight sugars. To consume this complex organic matter, microbes must initially produce enzymes of the correct structural specificity to transform it to smaller pieces that can be brought into
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Contributions of the Yangtze River and Yellow River to terrestrial organic carbon deposition in the Yangtze River Estuary during the last 700 years Mar. Chem. (IF 3.0) Pub Date : 2023-07-31 Yi Yang, Chao Gao, Kweku Afrifa Yamoah, Xiaoxia Lü, Xiaoyan Ruan, Huan Yang, Shucheng Xie
Terrestrial organic carbon (OC) could be transported to marginal oceans by large rivers and deposited under different hydrological conditions. A mixture of the fresh & lithospheric OC, superimposed by the OC from different rivers, makes it challenging to distinguish sources and contributions of terrestrial OC. Here, we employed multiple geochemical proxies, including the hydrogen isotopic composition
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Linkages between fluorescent dissolved organic matter and lignin phenols in the Canada Basin, Arctic Ocean Mar. Chem. (IF 3.0) Pub Date : 2023-07-24 Nicolas Sylvestre, Céline Guéguen
Lignin is one of the more refractory components of dissolved organic matter (DOM) and its concentration and composition are used to trace terrigenous DOM in the ocean. In this study, lignin oxidation products (LOP), and chromophoric and fluorescent DOM were measured in Polar Mixed Layer (PML), Atlantic water (AW), and Canada Basin Deep Water (CBDW) layers in the Canada Basin to elucidate the composition
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An empirical projection of ocean acidification in southwestern Japan over the 21st century Mar. Chem. (IF 3.0) Pub Date : 2023-07-24 Naohiro Kosugi, Hisashi Ono, Katsuya Toyama, Hiroyuki Tsujino, Masao Ishii
Most of Japan's coral reefs are distributed in the Ryukyu Islands, in the southwestern part of Japan. Since they support biodiversity in the tropical and subtropical seas and are vulnerable to ocean acidification as well as ocean heat waves and pollution, projecting acidification over multidecadal or longer periods of time is a great interest. Currently, the majority of long-term acidification projections
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Behaviour of barium in the tropical estuaries: Implications to its marine budgets and paleo-oceanographic applications Mar. Chem. (IF 3.0) Pub Date : 2023-07-16
Marine Barium (Ba) is extensively used as a tracer for biogeochemical processes and paleo-oceanographic proxy for past river discharge, salinity, and long-term hydrological changes. However, poor constrain on the riverine Ba flux to oceans due to its modification in the estuary hinder such applications. The prerequisite for an accurate Ba flux estimate is to have a detailed understanding of Ba behaviour
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Mixing behavior of dissolved organic matter at the Yukon and Kolyma land ocean interface Mar. Chem. (IF 3.0) Pub Date : 2023-07-20 Anne M. Kellerman, Peter J. Hernes, Amy M. McKenna, J. Blake Clark, Augusta Edmund, Brice Grunert, Paul J. Mann, Antonio Mannino, Michael Novak, Aron Stubbins, Maria Tzortziou, Nikita Zimov, Robert G.M. Spencer
Unprecedented rates of climate change in the Arctic are causing altered land to ocean transport of dissolved organic matter (DOM) and subsequent processing in the Arctic Ocean. Low salinity waters have been suggested as hotspots for DOM dynamics. Although a wide range of biogeochemical processes have been observed in temperate and tropical estuaries, very little is known about DOM behavior at the Arctic
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Spatial and seasonal distribution of particulate phosphorous and nitrogen in the Persian Gulf: Nitrogen enrichment ties to diazotroph bloom in stratified warm waters Mar. Chem. (IF 3.0) Pub Date : 2023-07-16
Understanding the particulate organic and inorganic forms of nutrients and their elemental stoichiometry in suspended particulate matter of marginal seas has important implications in several areas. Here, we present the findings from two consecutive research expeditions conducted in September 2021 and January 2022 aboard the Persian Gulf Explorer research vessel, focused on the particulate P and N
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Strong particle dynamics counteract the nutrient-pumping effect leading to weak carbon flux in a cyclonic eddy Mar. Chem. (IF 3.0) Pub Date : 2023-07-16 Xiao-Yuan Zhu, Zixiang Yang, Yuyuan Xie, Kuanbo Zhou, Wei-Lei Wang
Sinking particles play a crucial role in transferring carbon from the atmosphere to the deep ocean. However, due to intensive particle transformations such as aggregation, disaggregation, and remineralization, only a small portion of the organic carbon produced in the euphotic zone ends up being sequestered in the deep ocean or sediment. Mesoscale eddies can significantly impact the surface ocean nutrient
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Abundance of colloidal organic phosphorus in the Taiwan Strait Mar. Chem. (IF 3.0) Pub Date : 2023-07-07 Liangshi Lin, Guoxiang Chen, Xiuwu Sun, Hua Cheng, Bangqin Huang, Pinghe Cai, Min Chen, Yuanbiao Zhang, Yihua Cai
The Taiwan Strait is a coastal sea with dynamic hydrologic condition and dissolved organic matter (DOM) cycling. To better understand its phosphorus (P) transformation, phosphate and bulk dissolved organic phosphorus (DOP) concentrations were determined in the surface water of the Taiwan Strait during 2010 and 2011 summers. The bulk DOP was further fractionated into the low molecular weight (LMW) DOP
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Trace metal dissolution kinetics of East Asian size-fractionated aerosols in seawater: The effect of a model siderophore Mar. Chem. (IF 3.0) Pub Date : 2023-07-07 Hsin-Yen Wu, Chih-Chiang Hsieh, Tung-Yuan Ho
Aerosol soluble metals are considered bioavailable to marine phytoplankton and may influence phytoplankton growth, their community structure, and material cycling in the ocean. The dissolution is controlled by the physical and chemical properties of aerosols and various atmospheric, physical, and biogeochemical processes before and after depositing in the surface water. Among these complicated processes
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Organic alkalinity dynamics in Irish coastal waters: Case study Rogerstown Estuary Mar. Chem. (IF 3.0) Pub Date : 2023-06-25 Daniel E. Kerr, Anthony Grey, Brian P. Kelleher
Total alkalinity (TA) is a popularly measured carbonate system parameter and is widely used in calculations of key carbonate system descriptors such as the calcium carbonate saturation state, an important indicator of ocean acidification. Organic alkalinity (OrgAlk) is recognised as a contributor to TA in coastal waters, with this having implications on the use of TA to calculate key carbonate chemistry
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Applicability of meteoric 10Be in dating marine sediment cores Mar. Chem. (IF 3.0) Pub Date : 2023-06-28 Partha Sarathi Jena, Ravi Bhushan, Shivam Ajay, Ankur J. Dabhi, Mahesh Gaddam, A.K. Sudheer
Quaternary paleoclimatic and paleomagnetic reconstructions using marine sediment cores require appropriate dating techniques in order to build the chronology. Due to the widespread use of the radiocarbon dating method, the majority of studies focusing on paleo reconstructions are restricted to the last 50 ka. There are very few methods those can be used to obtain chronology beyond the radiocarbon dating
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Origin of dissolved organic sulfur in marine waters and the impact of abiotic sulfurization on its composition and fate Mar. Chem. (IF 3.0) Pub Date : 2023-06-26 Hamida Ibrahim, Luc Tremblay
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Benthic fluxes and mineralization processes at the scale of a coastal lagoon: Permeable versus fine-grained sediment contribution Mar. Chem. (IF 3.0) Pub Date : 2023-06-26 Céline Charbonnier, Pierre Anschutz, Joseph Tamborski, Pieter van Beek
Benthic fluxes of biogenic compounds play a major role in the biogeochemistry of shallow aquatic environments. Quantifying these fluxes at the scale of a lagoon is a challenge, especially when sediments are heterogeneous and fluxes at the sediment-water interface combine diffusive and advective transport processes. Diagenetic processes and associated benthic fluxes were quantified across different
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The roles of carbonate, borate, and bicarbonate ions in affecting zooplankton hatching success under ocean acidification Mar. Chem. (IF 3.0) Pub Date : 2023-06-21 John P. Christensen
Two ocean acidification studies about egg hatching success (HS) in geographically important marine copepods, Calanus finmarchicus and C. helgolandicus, were reanalyzed with improved statistical procedures. The new results at low and moderate levels of seawater acidification showed no HS inhibition at normal habitat temperatures but statistically significant inhibition at warmer and colder temperatures
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The solubility and deposition flux of East Asian aerosol metals in the East China Sea: The effects of aeolian transport processes Mar. Chem. (IF 3.0) Pub Date : 2023-06-16 Chih-Chiang Hsieh, Chen-Feng You, Tung-Yuan Ho
Aerosol dissolvable metals are considered to be readily bioaccessible so that their input would influence the growth and composition of marine phytoplankton and affect elemental cycling globally. However, it is highly challenging to measure or estimate reliable deposition fluxes of aerosol dissolvable metals in the ocean partially due to the impacts of complicated processes involved in pre- and post-deposition
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Seasonal dynamics of sinking organic matter in the Pacific Arctic Ocean revealed by nitrogen isotope ratios of amino acids Mar. Chem. (IF 3.0) Pub Date : 2023-06-12 Hyuntae Choi, Eun Jin Yang, Sung-Ho Kang, Dongseon Kim, Kyung-Hoon Shin
The Pacific Arctic Ocean has experienced a rapidly changing climate, sea-ice retreat, and enhanced primary production over the past few decades. The export production generated by photoautotrophs and heterotrophs has been characterized in the Arctic Ocean, but their seasonal variations in relative proportion are largely unknown due to the limited access in the ice-covered season. We measured the concentration
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Volcanogenic fluxes of iron from the seafloor in the Amundsen Sea, West Antarctica Mar. Chem. (IF 3.0) Pub Date : 2023-06-10 Lisa C. Herbert, Allison P. Lepp, Santiago Munevar Garcia, Arianne Browning, Lauren E. Miller, Julia Wellner, Silke Severmann, Claus-Dieter Hillenbrand, Joanne S. Johnson, Robert M. Sherrell
The Amundsen Sea in the Pacific sector of West Antarctica receives meltwater from the fastest retreating Antarctic glaciers, and its coastal polynyas host the highest primary productivity per unit area observed on the Antarctic continental shelf. Polynya productivity provides the base for a robust, diverse ecosystem and is controlled primarily by light and the availability of the micronutrient iron
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Seawater alkalinity enhancement with magnesium hydroxide and its implication for carbon dioxide removal Mar. Chem. (IF 3.0) Pub Date : 2023-06-07 Bo Yang, Jessica Leonard, Chris Langdon
For the first time we used lab and wind-wave tank experiments to prove the concept of using Mg(OH)2 for the ocean alkalinity enhancement and carbon dioxide removal approach (OAE-CDR). Experiment results showed up to 370 μmol kg−1 seawater total alkalinity (TA) increase without precipitation, stable enhanced TA, and OAE-CDR efficiency (ΔDIC/ΔTA) consistent with theoretical calculation. Based on the
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Spatial and temporal occurrence of preformed nitrate anomalies in the subtropical North Pacific and North Atlantic oceans Mar. Chem. (IF 3.0) Pub Date : 2023-05-25 Adam J. Smyth, Robert T. Letscher
Preformed nitrate (PreNO3) was formulated to act as a conservative tracer of ocean circulation after accounting for the stoichiometry of marine biochemical reactions involving oxygen and nitrate. However, PreNO3 anomalies (e.g. negative values) have been identified within the shallow subsurface of the subtropical ocean which still have yet to be fully explained. The mechanisms proposed to drive the