Marine Chemistry最新文献_第3页

Relationships between chemical composition of Arctic FeMn formations and their sorption properties for 137Cs and 90Sr radionuclides 北极地区FeMn地层化学组成与其对137Cs和90Sr放射性核素吸附特性的关系

IF 2.5 3区地球科学 Q2 CHEMISTRY, MULTIDISCIPLINARY

Marine Chemistry

Pub Date : 2025-11-17 DOI: 10.1016/j.marchem.2025.104582

Svetlana Bratskaya , Andrey Egorin , Denis Balatskiy , Marina Palamarchuk , Natalia Polyakova , Alexander Ulyantsev

Shallow-water FeMn formations in Arctic are usually not considered as a valuable mineral resource due to sub-economic contents of rare earth and critical metals. However, fast growth rate and unique chemical composition make them interesting candidates for application in environment protection and remediation. Here we have investigated the potential of the Chaun Bay (East Siberian Sea) FeMn formations for application as selective sorbents for ¹³⁷Cs and ⁹⁰Sr. FeMn formations collected at three stations located inside and nearby submarine groundwater discharge demonstrated highly variable chemical compositions with Fe/Mn ratios (0.058–0.71) and element contents up to 26.65 % (Fe), 17.79 % (Mn), 4.40 % (P), 6.34 % (Al), 15.52 % (Si). Sr contents varied from 880 to 2560 ppm. Akaganeite (β-FeOOH) was identified as the main Fe phase in crusts, while nodules were composed by lepidocrocite (γ-FeOOH) and/or feroxyhite (δ-FeOOH). Sorption properties of FeMn formations toward ¹³⁷Cs and ⁹⁰Sr were investigated from low salinity solutions and seawater. The sorption capacity and distribution coefficients (K_d) for ¹³⁷Cs correlated with aluminosilicates contents, while all phases (Fe and Mn oxyhydroxides, phosphates, and silicates) contributed to the ⁹⁰Sr uptake. FeMn formations with high P and Mn contents demonstrated an ultimately high selectivity toward ⁹⁰Sr in seawater with K_d up to 517 mL/g for Mn-rich sample that is comparable or better than the selectivity of the most known synthetic sorbents. The results obtained not only confirm the possibility of FeMn nodules application for radioactive waste treatment but open up prospects for the nature-inspired design of the composite sorption materials.

由于稀土和关键金属的亚经济含量，北极浅水FeMn地层通常不被认为是有价值的矿产资源。然而，其快速的生长速度和独特的化学成分使其在环境保护和修复方面具有重要的应用前景。在这里，我们研究了Chaun湾（东西伯利亚海）FeMn地层作为137Cs和90Sr选择性吸附剂的潜力。在海底地下水排放内部和附近的三个站点收集的FeMn地层显示出高度变化的化学成分，Fe/Mn比（0.058-0.71），元素含量高达26.65% (Fe), 17.79% (Mn), 4.40% (P), 6.34% (Al), 15.52% （Si）。锶含量从880到2560 ppm不等。赤线石（β-FeOOH）是地壳中主要的铁相，而结核则由绢云母（γ-FeOOH）和（或）铁氧化石（δ-FeOOH）组成。研究了低盐度溶液和海水中FeMn对137Cs和90Sr的吸附性能。137Cs的吸附量和分配系数（Kd）与铝硅酸盐含量相关，而所有相（Fe和Mn氧氢氧化物、磷酸盐和硅酸盐）都对90Sr的吸收有贡献。具有高P和Mn含量的FeMn地层对富Mn样品在Kd高达517 mL/g的海水中对90Sr具有较高的选择性，与大多数已知的合成吸附剂的选择性相当或更好。研究结果不仅证实了FeMn结核应用于放射性废物处理的可能性，而且为复合吸附材料的自然设计开辟了前景。

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引用次数: 0

The impacts of chemical composition on bacterial processing of dissolved organic matter in the deep Arctic Ocean 北冰洋深处化学成分对细菌处理溶解有机物的影响

IF 2.5 3区地球科学 Q2 CHEMISTRY, MULTIDISCIPLINARY

Marine Chemistry

Pub Date : 2025-11-14 DOI: 10.1016/j.marchem.2025.104579

N. Sylvestre, C. Guéguen

The cycling of dissolved organic matter (DOM) in the ocean plays a central role in carbon dynamics, influencing the ocean's ability to sequester carbon and regulate climate. However, the microbial processes that govern the transformation and persistence of DOM across different water masses remain poorly understood. In this study, we explore how a single bacterial community processes DOM from four distinct water masses (i.e, Pacific winter water, Atlantic halocline, Atlantic water - Barents Sea Strait branch, and deep temperature minimum) in the Canada Basin of the Arctic Ocean, using a combination of optical and molecular techniques to reveal the microbial mechanisms behind DOM reactivity and persistence. Although all water masses contained the same fluorescent components, each underwent unique processing by the microbial community after 20 days of laboratory-controlled incubation. This suggests that the composition of specific fluorescent components likely varies between different water layers, with an increase in these features by the end of the incubation. The number of common molecular features measured with a trapped ion mobility spectrometer coupled with a time-of-flight mass spectrometer (TIMS-TOF) and an electrospray ionization source (positive ionization mode) was higher in contiguous water masses, likely due to water mass mixing resulting in the formation of the Atlantic halocline. Spearman's rank correlations between fluorescence characteristics and TIMS-TOF features established connections between fluorescent characteristics and molecular formulas. Twenty-two distinct molecular features were related to the four humic-like. None of them were associated with tyrosine-like, revealing the distinct molecular-optical linkages between humic- and protein-like DOM. Overall, our findings indicate that the DOM reactivity depends on its optical and molecular composition. The mechanistic understanding of the factors that control the persistence of DOM in the ocean is essential for predicting the ocean's role in the global carbon cycle.

海洋中溶解有机物（DOM）的循环在碳动态中起着核心作用，影响海洋固碳和调节气候的能力。然而，控制DOM在不同水体中的转化和持久性的微生物过程仍然知之甚少。在这项研究中，我们探索了来自北冰洋加拿大盆地四种不同水体（即太平洋冬季水、大西洋盐跃层、大西洋水-巴伦支海海峡分支和深层最低温度）的单一细菌群落如何处理DOM，利用光学和分子技术相结合的方法揭示了DOM反应性和持久性背后的微生物机制。虽然所有的水团都含有相同的荧光成分，但经过20天的实验室控制孵育后，每个水团都经历了微生物群落的独特处理。这表明，特定荧光成分的组成可能在不同水层之间有所不同，在孵育结束时这些特征有所增加。用捕获离子迁移率谱仪、飞行时间质谱仪（TIMS-TOF）和电喷雾电离源（正电离模式）测量的共同分子特征的数量在连续的水团中更高，可能是由于水团混合导致了大西洋盐斜的形成。荧光特性与TIMS-TOF特性之间的Spearman秩相关建立了荧光特性与分子式之间的联系。22个不同的分子特征与4个腐殖质样有关。它们都没有与酪氨酸样相关，这揭示了腐殖质和蛋白质样DOM之间独特的分子光学联系。总的来说，我们的发现表明DOM的反应性取决于它的光学和分子组成。对控制DOM在海洋中持续存在的因素的机制理解对于预测海洋在全球碳循环中的作用至关重要。

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引用次数: 0

Advancing the characterization of organic Cu(II)-binding ligands in Arctic Ocean waters: Integration of IMAC, SPE, HRMS, and fluorescence techniques 推进北冰洋水体中有机Cu（II）结合配体的表征：IMAC、SPE、HRMS和荧光技术的整合

IF 2.5 3区地球科学 Q2 CHEMISTRY, MULTIDISCIPLINARY

Marine Chemistry

Pub Date : 2025-11-10 DOI: 10.1016/j.marchem.2025.104578

Louis Criqui, Céline Guéguen

The availability and toxicity of dissolved copper (Cu) in the ocean are largely determined by its complexation with organic ligands, but the structure and origin of these ligands are still largely unknown. In this work, standard and marine Cu(II) complexing ligands were isolated using immobilized metal affinity chromatography (IMAC) and solid phase extraction (SPE), and characterized using high-resolution mass spectrometry (HRMS) and excitation-emission matrix (EEM) fluorescence to obtain information on the size distribution, molecular composition, and fluorescing properties of organic Cu(II)-binding molecules in the Arctic Ocean. We first investigated the retention performance of model ligands and found that N-containing ligands were preferentially isolated on the IMAC-SPE column. Application to Arctic Ocean dissolved organic matter (DOM) showed that the organic ligands accounted for up to 3 % of the DOM, consistent with previous studies. Robust correlations of HMRS peak intensities with EEM signals were used to expand chemical characterization of 511 molecular formulas in the IMAC-SPE and SPE extracts. The pairing based on the molecular classification associated with fluorescence signatures showed that 52 % Spearman correlations were linked to humic-like components. The necessity of multiple molecular annotation methods, like HRMS/fluorescence correlation or van Krevelen class attribution, was demonstrated to yield a better molecular identification. The combination of IMAC, SPE, HRMS, and EEM appears to be a promising approach for the characterization of organic Cu(II)-binding ligands in waters.

海洋中溶解铜（Cu）的可用性和毒性在很大程度上取决于其与有机配体的络合作用，但这些配体的结构和来源在很大程度上仍然未知。本研究采用固定化金属亲和色谱（IMAC）和固相萃取（SPE）分离标准和海洋Cu（II）络合配体，并采用高分辨率质谱（HRMS）和激发发射矩阵（EEM）荧光技术对其进行表征，以获得北冰洋有机Cu（II）结合分子的大小分布、分子组成和荧光特性等信息。我们首先研究了模型配体的保留性能，发现含n的配体在IMAC-SPE柱上被优先分离。对北冰洋溶解有机质（DOM）的应用表明，有机配体占DOM的比例高达3%，与前人的研究结果一致。利用HMRS峰强度与EEM信号的鲁强相关性，扩展了IMAC-SPE和SPE提取物中511个分子式的化学表征。基于与荧光特征相关的分子分类的配对表明，52%的斯皮尔曼相关性与腐殖质样成分有关。为了获得更好的分子鉴定，需要采用多种分子注释方法，如HRMS/荧光相关或van Krevelen类归属。IMAC、SPE、HRMS和EEM的结合似乎是表征水中有机Cu（II）结合配体的一种很有前途的方法。

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引用次数: 0

Desorption dynamics of black carbon in a subtropical estuary 亚热带河口黑碳解吸动态

IF 2.5 3区地球科学 Q2 CHEMISTRY, MULTIDISCIPLINARY

Marine Chemistry

Pub Date : 2025-11-05 DOI: 10.1016/j.marchem.2025.104576

Qinghua Zhang , Weifeng Yang , Ziming Fang , Zeheng Lin , Minfang Zheng , Mengya Chen

The geochemical behavior of black carbon (BC) in the estuary system controls the magnitude of riverine BC into coastal seas and thus the budget of BC in the ocean. However, the poor understanding of BC behavior in estuaries prevents us from well quantifying the riverine BC export. Here, eight cruises were conducted in the Jiulong River estuary to delineate the behavior of dissolved black carbon (DBC) determined using the benzenepolycarboxylic acid (BPCA) method, as well as its influence on riverine DBC estimation. DBC showed a range of 1.16–7.88 μmol L⁻¹. On an estuarine scale, DBC correlated negatively with salinity in all cruises (p < 0.05), revealing a dominant dilution effect of seawater during the transport of riverine DBC to the Taiwan Strait. Notably, the continuous addition behavior of DBC was identified in the low salinity zones based on high-solution samplings, attributing to the desorption of soluble BC from particulate matter. Simulation analysis indicated that the desorption followed a pseudo-first-order kinetic law. The kinetic constants varied from 0.053 h⁻¹ to 0.84 h⁻¹ with the maximum in summer. Incorporating desorbed DBC, the annual export rate of riverine DBC was 1.1 Gg yr⁻¹, about 26 % higher than 0.9 Gg yr⁻¹ estimated based on the traditional algorithm (i.e., without addition). The first examination of DBC desorption kinetics provided insights into the behavior of BC in the estuary and the riverine DBC magnitude into the ocean.

河口系统中黑碳的地球化学行为控制着河流中黑碳进入近海的量，从而控制着海洋中黑碳的收支。然而，对河口BC行为的了解不足，使我们无法很好地量化河流BC出口。在九龙江入海口进行了8次巡航，研究了苯聚羧酸（BPCA）法测定溶解黑碳（DBC）的行为及其对河道DBC估算的影响。DBC为1.16 ~ 7.88 μmol L−1。在河口尺度上，所有航次的DBC与盐度呈负相关（p < 0.05），表明在河流DBC向台湾海峡的运输过程中，海水的稀释作用占主导地位。值得注意的是，基于高溶液采样，在低盐度区发现了DBC的连续添加行为，这归因于可溶BC从颗粒物中解吸。模拟分析表明，解吸过程遵循准一级动力学规律。动力学常数变化范围为0.053 ~ 0.84 h−1，夏季最大。考虑解吸DBC后，河流DBC的年出口量为1.1 Gg yr - 1，比传统算法（即不添加）估计的0.9 Gg yr - 1高出约26%。对DBC解吸动力学的第一次检查提供了对BC在河口和河流DBC量级进入海洋的行为的见解。

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引用次数: 0

Source contributions to iron cycling in marginal sea: Evidence from Iron isotope compositions of Changjiang Estuary sediments 来源对边缘海铁循环的贡献：来自长江口沉积物铁同位素组成的证据

IF 2.5 3区地球科学 Q2 CHEMISTRY, MULTIDISCIPLINARY

Marine Chemistry

Pub Date : 2025-10-30 DOI: 10.1016/j.marchem.2025.104575

Jiao Wang , Ziwei Sun , Huamao Yuan , Jinming Song , Ning Li , Chen Li , Yuanyuan Xiao

As an important input area of riverine and terrigenous materials in the east coast of China, the knowledge on iron budget of marginal sea sediments in the Changjiang Estuary is significant to understand the iron cycle of marginal sea ecosystems. Iron isotope composition has been recently used as a critical indicator for understanding the iron cycle and biogeochemical processes of the Earth. This study reports the iron isotope variation of two sediment cores from the Changjiang Estuary, i.e., 3100–1 and DH5. The δ⁵⁶Fe values of samples from the core 3100–1 vary from +0.02 ‰ to +0.08 ‰ with an average of +0.05 ± 0.03 ‰, and the δ⁵⁶Fe values of samples from the core DH5 range from +0.02 ‰ to +0.10 ‰, with an average of +0.07 ± 0.05 ‰. The δ⁵⁶Fe values of sediments from these two cores are not significantly correlated with parameters for organic carbon content, chemical weathering, grain size, or redox condition. Together with the Principal Component Analysis, these indicate that source material inputs significantly affect iron isotope compositions in both cores. Meanwhile, the iron isotope compositions of the core DH5 can reflect changes of human activities in the Changjiang Basin. Our findings provide pivotal iron isotope evidence for understanding the marginal sea iron cycle under natural and anthropogenic impacts, offering an important perspective for further studies on the global marginal sea ecosystem.

长江口边缘海沉积物作为中国东部沿海重要的河流和陆源物质输入区，其铁收支对了解边缘海生态系统的铁循环具有重要意义。近年来，铁同位素组成已被用作了解地球铁循环和生物地球化学过程的重要指标。本文报道了长江口3100-1和DH5两个沉积物岩心的铁同位素变化。3100-1岩心样品δ56Fe值变化范围为+0.02‰~ +0.08‰，平均值为+0.05±0.03‰；DH5岩心样品δ56Fe值变化范围为+0.02‰~ +0.10‰，平均值为+0.07±0.05‰。两个岩心沉积物的δ56Fe值与有机碳含量、化学风化、粒度、氧化还原条件等参数的相关性不显著。主成分分析表明，源物质输入对两个岩心的铁同位素组成有显著影响。同时，DH5岩心铁同位素组成可以反映长江流域人类活动的变化。研究结果为理解自然和人为影响下的边缘海铁循环提供了关键的铁同位素证据，为进一步研究全球边缘海生态系统提供了重要的视角。

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引用次数: 0

Dynamic organic matter sources drive intact polar lipids recently deposited in surface sediments from the Yangtze River Estuary and adjacent sea 动态有机质源驱动了长江口及邻近海域表层沉积物中近期沉积的完整极性脂质

IF 2.5 3区地球科学 Q2 CHEMISTRY, MULTIDISCIPLINARY

Marine Chemistry

Pub Date : 2025-10-29 DOI: 10.1016/j.marchem.2025.104574

Dayu Duan , Ke Xu , Yuxue Yang , Yue Wu , Yasong Wang , Yuli Wei , Wenjie Xiao , Zhixuan Feng , Xueqin Zhao , Yunping Xu , Weichao Wu

Lipids, especially the intact polar lipids, serve as valuable biological information for biogeochemical studies. However, the distributions of sedimentary lipids and their controlling factor in dynamic estuarine systems remain poorly constrained. Here we used an untargeted lipidomics approach to analyze lipid composition in surface sediments across freshwater, turbidity and inner shelf zones in the Yangtze River estuary. A total of 852 lipids from 28,378 molecular features were annotated, covering 35 subclasses based on LIPIDMAPS framework. The most abundant lipids, including subclasses free fatty acids, triacylglycerols, ceramides, diacylglyceryl trimethylhomoserines, and phosphatidylcholines, accounted for up to 71.4 %. Multivariate analysis reveals a significant effect of total organic carbon δ¹³C values (δ¹³C-TOC) and grain size on lipid distribution, suggesting that sedimentary organic matter sources and hydrodynamic conditions are key controlling factors on spatial lipid heterogeneity. An apparent seawards increase in δ¹³C-TOC values (−24.7 − −20.4 ‰) indicates contribution of phytoplankton-derived organic matter to sedimentary TOC from the adjacent sea area. However, most putatively eukaryotic lipids, including phospholipids, glycerolipids and betaine lipids, exhibit no distinct seawards pattern. This pattern is likely attributed to the integrative effect between lipid degradation of riverine phytoplankton and replenishment of marine phytoplankton with the resuspension of sediment. In contrast, most ceramides, especially phytosphingosine-based ceramides, show a substantially decreasing trend seawards and a strongly negative association with δ¹³C-TOC (r < −0.8, p < 0.001), probably indicating a terrestrial origin. This study highlights the lipid diversity under the complex marine dynamics and the potential use of lipids for tracing the biogeochemical cycling of polar lipids in the ocean.

脂质，尤其是完整的极性脂质，是生物地球化学研究的重要生物信息。然而，对动态河口体系中沉积脂类的分布及其控制因素的研究仍然缺乏深入的认识。本文采用非靶向脂质组学方法分析了长江口淡水带、浑浊带和内陆架带表层沉积物的脂质组成。基于LIPIDMAPS框架，共对28378个分子特征中的852个脂类进行了注释，涵盖35个亚类。最丰富的脂类，包括亚类游离脂肪酸、三酰甘油、神经酰胺、二酰甘油三甲基高丝氨酸和磷脂酰胆碱，占71.4%。多变量分析显示，总有机碳δ13C值（δ13C- toc）和颗粒大小对脂质分布有显著影响，表明沉积有机质来源和水动力条件是控制脂质空间异质性的关键因素。δ13C-TOC值（- 24.7‰~ - 20.4‰）向海方向明显增加，表明浮游植物源有机质对邻近海域沉积TOC有贡献。然而，大多数被认为是真核生物的脂质，包括磷脂、甘油脂和甜菜碱脂，并没有明显的海向模式。这种模式可能归因于河流浮游植物的脂质降解和海洋浮游植物的补充与沉积物的再悬浮之间的综合作用。相反，大多数神经酰胺，特别是植物鞘氨醇基神经酰胺，呈现出向海方向显著降低的趋势，与δ13C-TOC呈强负相关（r <−0.8,p < 0.001），可能是陆源的。本研究强调了复杂海洋动态下的脂质多样性，以及脂质在海洋极地脂质生物地球化学循环中的潜在应用。

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引用次数: 0

pHT measurements of TRIS buffer solutions in artificial seawater matrix in the salinity range 5–40 and temperature range 5–40 °C. Part 2: Uncertainty of pHT values TRIS缓冲溶液在人工海水基质中盐度范围5-40，温度范围5-40°C的pHT测量。第2部分：pHT值的不确定度

IF 2.5 3区地球科学 Q2 CHEMISTRY, MULTIDISCIPLINARY

Marine Chemistry

Pub Date : 2025-10-17 DOI: 10.1016/j.marchem.2025.104573

Rieke Schäfer , Gaëlle Capitaine , Frank Bastkowski , Daniela Stoica , Olivier Pellegrino , Raquel Quendera , Eric P. Achterberg , Simon L. Clegg , Paola Fisicaro , Steffen Seitz

In the first part of this study, we determined a fit function which allows the calculation of the total pH (pH

_{T}

) value of an artificial seawater/2-amino-2-(hydroxymethyl)-1,3-propanediol (TRIS) buffer, extrapolated to 0 mol kg⁻¹ H

_{2}

O TRIS molality (i.e. to a true pH

_{T}

scale), in terms of temperature and practical salinity. In this second part, we present a method to quantify the uncertainty of that function. The uncertainty plays an important role in the characterization of the indicator dye used for the routine spectrophotometric pH

_{T}

measurement in seawater. However, it has not been determined previously. We assigned uncertainties to measured input quantities, and propagated them through the calculation steps described in the first part. Both, analytical uncertainty calculation and Monte Carlo simulations have been applied to adequately consider the various steps of the procedure needed to calculate pH

_{T}

values of artificial seawater. The combined standard uncertainty of pH

_{T} (S, T, b (TRIS) = 0 mol kg^{−1} H_{2} O)

for artificial seawater/TRIS buffers was 0.0011 over the practical salinity range 5 to 40 and temperature range 5 °C to 40 °C. This uncertainty can now be used to determine, the uncertainties of the characterization of the indicator dye used for seawater pH

_{T}

measurements.

在本研究的第一部分中，我们确定了一个拟合函数，该函数允许计算人工海水/2-氨基-2-（羟甲基）-1,3-丙二醇（TRIS）缓冲液的总pH （pHT）值，根据温度和实际盐度外推到0 mol kg−1 H2O TRIS质量摩尔浓度（即真正的pHT刻度）。在第二部分中，我们提出了一种量化该函数不确定性的方法。不确定度在常规分光光度法测定海水pHT的指示剂的表征中起着重要的作用。然而，它之前并没有确定。我们将不确定性分配给测量的输入量，并通过第一部分中描述的计算步骤传播它们。分析不确定度计算和蒙特卡罗模拟都被用于充分考虑计算人工海水pHT值所需的程序的各个步骤。人工海水/TRIS缓冲液的pHT（S，T,b(TRIS)=0mol kg−1H2O）在实际盐度5 ~ 40、温度5℃~ 40℃范围内的联合标准不确定度为0.0011。这种不确定度现在可以用来确定用于海水pHT测量的指示剂染料特性的不确定度。

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引用次数: 0

Polyamines as predominant organic basic compounds in the Antarctic Peninsula 多胺是南极半岛主要的有机碱性化合物

IF 2.5 3区地球科学 Q2 CHEMISTRY, MULTIDISCIPLINARY

Marine Chemistry

Pub Date : 2025-10-12 DOI: 10.1016/j.marchem.2025.104572

Kentaro Saeki , Daniel P. Zitterbart , Kazuya Ikari , Joseph D. Warren , Kylie Owen , Shin-Ichi Ohira , Kei Toda

Polyamines, such as putrescine, spermidine, and spermine, are vital for marine microorganisms as nutrients and bioactive compounds. While their presence has been studied in various marine regions, they remain unexamined in the Antarctic region, and no study has compared polyamines with monoamines, another class of organic nitrogen compounds. This study quantified polyamines and monoamines in seawater in the West Antarctic Peninsula region using 4-(N,N-dimethylaminosulfonyl)-7-fluoro-2,1,3-benzoxadiazole (DBD-F) derivatization and HPLC-MS/MS. Polyamines were detected in Antarctica for the first time at sub-μM to μM levels, and it was approximately two orders of magnitude higher than reports from lower-latitude regions. Although total polyamine concentrations did not differ significantly among the five sites sampled, distinct patterns in polyamine composition were observed between the sites. In Wilhelmina Bay, total polyamines exhibited a positive but non-significant association with zooplankton backscatter (NASC), while cadaverine alone correlated significantly (r = 0.53, n = 15, p = 0.04). Our results established a baseline for Antarctic polyamines and revealed bay-to-bay differences in species composition. These baseline observations set the stage for tracking how polyamine dynamics respond to environmental change in the Southern Ocean.

多胺，如腐胺、亚精胺和精胺，作为营养物质和生物活性化合物对海洋微生物至关重要。虽然在不同的海洋区域对它们的存在进行了研究，但它们在南极地区仍未得到研究，而且没有研究将多胺与单胺（另一类有机氮化合物）进行比较。本研究采用4-（N，N-二甲氨基磺酰基）-7-氟-2,1,3-苯并恶二唑（DBD-F）衍生化和HPLC-MS/MS技术对南极半岛西部地区海水中的多胺和单胺进行了定量分析。在南极首次检测到亚μM ~ μM水平的多胺，比低纬度地区报道的多胺含量高约2个数量级。虽然总多胺浓度在五个采样点之间没有显着差异，但在不同的地点之间观察到不同的多胺组成模式。在Wilhelmina Bay，总多胺与浮游动物反向散射（NASC）呈显著正相关（r = 0.53, n = 15, p = 0.04）。我们的结果建立了南极多胺的基线，并揭示了海湾间物种组成的差异。这些基线观测为跟踪多胺动力学如何响应南大洋环境变化奠定了基础。

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引用次数: 0

Acid-leachability of metals from suspended particles in the Pacific Ocean 太平洋悬浮颗粒中金属的酸浸性

IF 2.5 3区地球科学 Q2 CHEMISTRY, MULTIDISCIPLINARY

Marine Chemistry

Pub Date : 2025-10-10 DOI: 10.1016/j.marchem.2025.104571

Yoshiki Sohrin , Linjie Zheng , Cheuk-Yin Chan , Yuzuru Nakaguchi , Shotaro Takano , Rumi Sohrin , Wen-Hsuan Liao , Tung-Yuan Ho

Suspended particles are major carriers of trace metals in seawater, while the cycling mechanisms of particulate trace metals remain largely unclear owing to analytical challenges. In this study, we focused on the acid-leachability of particulate trace metals collected from the Pacific Ocean and investigated their compositional features by measuring the total dissolvable metal (tdM) and dissolved metal (dM) concentrations in unfiltered and filtered seawater samples, respectively. We defined the difference between total dissolvable and dissolved metals as the particulate metal (pM). We investigated the pM time course in acidified bottom waters (pH 1.9) over approximately two years. pM increased in two stages and reached equilibrium within a few years. In the field study, we stored acidified seawater samples at least two years before analysis. We compared pM with total particulate metal (tpM) concentrations in the same samples collected from 11 stations in the subarctic Pacific. The tpM concentrations were determined by particle filtration followed by total digestion using strong acids, including HF. The results indicate that pAl and pFe are nearly equivalent to tpAl and tpFe, respectively. Many metals in the suspended particles, including clay minerals, are highly acid-leachable during long-time storage. By compiling our pM data observed in the Pacific Ocean and its marginal seas (approximately 1500 samples), we found that the average pM/dM ratio across the Pacific is 9 for Al and 4 for Fe. Although pAl and pFe exhibit strong linear correlations, their concentrations and regression slopes are spatially variable, reflecting differences in sources and fluxes.

悬浮颗粒是海水中微量金属的主要载体，但由于分析方面的挑战，颗粒微量金属的循环机制在很大程度上仍不清楚。本研究通过测定未过滤和过滤海水样品中总溶解金属（tdM）和溶解金属（dM）浓度，研究了太平洋海水中颗粒状微量金属的酸浸性，并探讨了其组成特征。我们将总可溶金属和溶解金属的区别定义为颗粒金属（pM）。在大约两年的时间里，我们研究了酸化水底（pH值1.9）的pM时间过程。pM分两个阶段增加，并在几年内达到平衡。在实地研究中，我们在分析前将酸化的海水样本至少保存了两年。我们比较了从亚北极太平洋11个站点收集的相同样品中的pM和总颗粒金属（tpM）浓度。采用颗粒过滤法测定tpM浓度，然后用强酸（包括HF）进行总消解。结果表明，pAl和pFe分别与tpAl和tfe几乎相等。悬浮颗粒中的许多金属，包括粘土矿物，在长期储存期间极易酸浸。通过汇编我们在太平洋及其边缘海域观测到的pM数据（大约1500个样本），我们发现整个太平洋的平均pM/dM比值为Al为9，Fe为4。尽管pAl和pFe表现出很强的线性相关性，但它们的浓度和回归斜率在空间上是可变的，反映了来源和通量的差异。

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引用次数: 0

Submarine groundwater discharge and gas hydrate dissociation fuel organic matter formation in Arctic fjord sediments 海底地下水排放和天然气水合物解离为北极峡湾沉积物有机质形成提供燃料

IF 2.5 3区地球科学 Q2 CHEMISTRY, MULTIDISCIPLINARY

Marine Chemistry

Pub Date : 2025-10-08 DOI: 10.1016/j.marchem.2025.104570

Beata Szymczycha , Magdalena Diak , Wei-Li Hong , Michael Ernst Böttcher , Aivo Lepland , Przemysław Makuch , Sophie ten Hietbrink , Seyed Reza Saghravani , Arunima Sen , Aleksandra Winogradow , Marc J. Silberberger

Arctic fjord sediments store significant amounts of organic matter (OM), contributing to the global carbon cycle, but are increasingly influenced by climate change. This study investigates OM distribution and sources in sediments from 24 stations across three West Spitsbergen fjords (Hornsund, Isfjord, and Kongsfjord-Krossfjord), focusing on relationships with porewater chloride concentrations and stable water isotopes. Freshening of porewater indicated by low chlorinity was detected in Isfjord and Hornsund. In Hornsund and Tempelfjord (Isfjord), water isotope signatures point to a meteoric origin, likely via submarine groundwater discharge (SGD). In contrast, Ekmanfjord (Isfjord) shows isotopic evidence of gas hydrate dissociation as the freshening source. Both Isfjord sites contain OM with low δ¹³C_org < –26.8 ‰) and δ¹⁵N_tot (< 3.1 ‰) values, which are inconsistent with known OM sources in Svalbard fjords. We propose that carbon released from SGD and gas hydrate dissociation, along with methane oxidation and nitrogen assimilation by methanotrophic microbes, contribute to OM formation. These findings suggest that Arctic fjord sediments may help mitigate climate change by supporting microbial processes that consume methane, a potent greenhouse gas.

北极峡湾沉积物储存了大量的有机物（OM），为全球碳循环做出了贡献，但受到气候变化的影响越来越大。本研究调查了西斯皮次卑尔根三个峡湾（Hornsund、Isfjord和kongsjord - krossfjord） 24个站点沉积物中OM的分布和来源，重点研究了孔隙水氯浓度和稳定水同位素的关系。在Isfjord和Hornsund检测到低氯含量的孔隙水变新鲜。在霍恩松德和坦普尔峡湾（Isfjord），水的同位素特征指向大气起源，可能是通过海底地下水排放（SGD）。相比之下，埃克曼峡湾（Isfjord）显示了天然气水合物解离作为新鲜来源的同位素证据。两个Isfjord遗址均含有低δ13Corg （< -26.8‰）和δ15Ntot （< 3.1‰）值的OM，这与斯瓦尔巴峡湾已知的OM来源不一致。研究人员认为，甲烷发酵过程中释放的碳和天然气水合物的解离，以及甲烷氧化和甲烷营养微生物对氮的同化，都有助于有机质的形成。这些发现表明，北极峡湾沉积物可能通过支持消耗甲烷（一种强效温室气体）的微生物过程来帮助减缓气候变化。

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引用次数: 0