Deep-Sea Research Part I-Oceanographic Research Papers最新文献_第7页

Northbound movement of northern fur seal (Callorhinus ursinus) and their response to the oceanographic features 北方海狗的北迁及其对海洋特征的响应

IF 2.1 3区地球科学 Q2 OCEANOGRAPHY

Deep-Sea Research Part I-Oceanographic Research Papers

Pub Date : 2025-07-18 DOI: 10.1016/j.dsr.2025.104558

Heping Li , Ryo Dobashi , Humio Mitsudera , Yoko Mitani

Northern fur seals (NFS; Callorhinus ursinus) are a highly migratory otariid species that leave breeding grounds in autumn (October–November), travel south to winter foraging grounds, and return to breeding colonies in early spring (March–April). NFS migrate south to regions with sufficient food, and their movement is hypothesized to be correlated with several oceanographic features. Although southward migration patterns are well-documented, fine-scale information on northbound migration remains limited owing to extended pelagic wintering periods and associated tracking challenges. Using satellite tags, we tracked five juvenile and subadult male NFS from a primary wintering ground in the Sea of Japan to examine their movement patterns, migration pathways, and behavioral responses to oceanographic features. Migration was divided into stay and northbound transit phases based on movement patterns. Slower movements with frequent course changes dominated the stay phase, whereas faster and more directed movements characterized the northbound transit phase. Foraging behavior was concentrated in continental shelf-break regions, where bathymetric features enhance prey availability. Foraging was most frequent within water temperature ranges of 8 °C–13 °C, corresponding to the highly productive Kuroshio-Oyashio Transition Zone. In contrast, transit behavior predominated at water temperatures below 2 °C and above 13 °C, likely reflecting physiological constraints. NFS also exhibited transit behavior near anticyclonic eddy edges, suggesting they use high-velocity regions to reduce travel costs. This study provides valuable insights into the northbound migration strategies of NFS overwintering in the Sea of Japan, demonstrating how they use specific oceanographic features for efficient foraging and movement during migration.

北方海豹(NFS；熊耳花椒（calorhinus ursinus）是一种高度迁徙性的耳科动物，它们在秋季（10 - 11月）离开繁殖地，向南旅行到冬季觅食地，并在早春（3 - 4月）返回繁殖地。NFS向南迁移到食物充足的地区，它们的迁移被认为与几个海洋学特征有关。虽然向南迁移的模式有充分的记录，但由于远洋越冬期延长和相关的跟踪挑战，向北迁移的精细信息仍然有限。利用卫星标签，我们从日本海的一个主要越冬地追踪了5只幼年和亚成年雄性NFS，研究了它们的运动模式、迁徙路径和对海洋特征的行为反应。根据迁移模式，迁移分为停留阶段和向北迁移阶段。较慢的运动和频繁的路线变化主导了停留阶段，而更快和更有针对性的运动是北行过境阶段的特征。觅食行为集中在大陆架断裂区域，那里的水深特征增加了猎物的可用性。8°C - 13°C的水温范围内，与黑潮-沽潮过渡区相对应，觅食活动最为频繁。相比之下，在水温低于2°C和高于13°C时，转运行为占主导地位，可能反映了生理限制。NFS在反气旋涡旋边缘附近也表现出了过境行为，这表明它们使用高速区域来降低旅行成本。这项研究为在日本海越冬的NFS向北迁移策略提供了有价值的见解，展示了它们如何利用特定的海洋特征在迁移过程中有效地觅食和移动。

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引用次数: 0

Biogenic Si cycling along the Cocos Ridge: differences between in situ and ex situ extracted pore waters imply rapid rates of dissolved Si uptake upon core recovery 沿Cocos岭的生物硅循环：原位和非原位提取孔隙水之间的差异意味着在岩心恢复时溶解硅的吸收速度很快

IF 2.3 3区地球科学 Q2 OCEANOGRAPHY

Deep-Sea Research Part I-Oceanographic Research Papers

Pub Date : 2025-07-04 DOI: 10.1016/j.dsr.2025.104554

Matthew P. Quinan , William M. Berelson , Jaclyn E.P. Cetiner , Nick E. Rollins , Frank J. Pavia , Sijia Dong , Janice L. Jones , Mark A. Brzezinski , Jess F. Adkins

The cycling of silicon (Si) in marine sediments can have major impacts on global ocean nutrient dynamics and productivity. Si cycling in the sediment of the Cocos Ridge and overlying waters of the eastern equatorial Pacific was investigated using unique in situ and traditional ex situ pore water collection techniques as well as solid phase analysis, core incubation, and sediment trap collection. Si remineralization and burial fluxes show little variation between the four sites investigated, regardless of a ∼1600 m difference in water depth among stations. Dissolved Si concentrations in pore water from sediment depths >10 cm collected in situ were significantly and consistently higher than those collected ex situ implying a previously unrecognized sampling artifact associated with sediment core recovery and processing. The loss of dissolved Si in the ex situ pore waters is also associated with the fractionation of Si isotopes. In situ pore water δ³⁰Si is lighter than ex situ pore water δ³⁰Si at three of the four stations, though only significantly lighter at one. The preferential loss of light Si in ex situ pore waters is attributed to authigenic clay formation during core collection and transport from the cold, high pressure benthos to the ocean's surface. However, consistency between in situ and ex situ pore water Si gradients within 10 cm of the sediment water interface indicates remineralization fluxes previously determined using sediment core-derived pore waters remain accurate.

海洋沉积物中硅（Si）的循环对全球海洋营养动态和生产力具有重要影响。利用独特的原位和传统的非原位孔隙水收集技术，以及固相分析、岩心培养和沉积物捕集器收集技术，研究了科科斯岭和赤道东太平洋上覆水域沉积物中的硅循环。Si再矿化和埋藏通量在4个调查地点之间几乎没有变化，而不管站点之间的水深相差约1600 m。原位采集的沉积物深度为10cm的孔隙水中溶解硅浓度显著且持续高于非原位采集的孔隙水中溶解硅浓度，这意味着与沉积物岩心恢复和处理相关的先前未被识别的采样人为影响。非原位孔隙水中溶解硅的损失也与硅同位素的分馏有关。4个测点中有3个测点的原位孔隙水δ30Si比非原位孔隙水δ30Si轻，只有1个测点的孔隙水δ30Si明显轻。非原位孔隙水中轻硅的优先损失归因于岩心收集和从寒冷高压底栖生物到海洋表面的运输过程中自生粘土的形成。然而，在沉积物水界面10厘米范围内，原位和非原位孔隙水Si梯度的一致性表明，先前使用沉积物岩心衍生孔隙水确定的再矿化通量仍然准确。

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引用次数: 0

The in situ Mg/Ca ratios of planktonic foraminifera shells in the northeastern South China Sea: an attempt to get efficient and reliable proxies 南海东北部浮游有孔虫壳原位Mg/Ca比值：一种有效可靠的代用指标的尝试

IF 2.3 3区地球科学 Q2 OCEANOGRAPHY

Deep-Sea Research Part I-Oceanographic Research Papers

Pub Date : 2025-07-03 DOI: 10.1016/j.dsr.2025.104553

Guanglu Zhang , Yanyan Zhao , Jun Yang , Sheng Liu , Zhishun Zhang , Xiaoqiang Guo , Guangyao Cao , Lei Yang , Sanzhong Li , Li Zou

Planktonic foraminifera are one of the important carriers of the physico-chemical environments. Recent advances in in situ microanalysis techniques provide new insights into the spatial distribution and variations of trace element concentrations of individual foraminifera shells. In this study, we focus on the variations of the in situ Mg/Ca ratios of four planktonic foraminifera species, which live in the different depths, from the surface sediments of the northeastern slope of the South China Sea (SCS). Both electron microprobe mapping and LA-ICP-MS results indicate that Globigerinoides ruber exhibits periodic bands with high Mg contents and Mg/Ca ratios, which may be attributed to symbionts. In contrast, Neogloboquadrina dutertrei, Pulleniatina obliquiloculata, and Globorotalia inflata exhibit thick calcite layers with low Mg/Ca ratios, potentially associated with calcite crusts. Meanwhile, high Mg/Ca ratios may be attributed to the contaminants, especially on the shell surface. These findings demonstrate that the variations of Mg/Ca ratios in foraminifera shells are controlled not only by the surrounding seawater temperature but also by other factors.

Applying this method, we reconstructed Mg/Ca-SST in the northeastern SCS over the past ∼3000 years. The results indicate that the reconstructed SST trend aligns with the previous regional records, which validates the robustness of the method. We hope that this method can be widely applied in the future due to the efficiency, rapid processing, and high spatial resolution with minimal sample requirements.

浮游有孔虫是物化环境的重要载体之一。原位微量分析技术的最新进展为有孔虫个体壳中微量元素浓度的空间分布和变化提供了新的认识。本文研究了南海东北坡表层沉积物中生活在不同深度的4种浮游有孔虫的原位Mg/Ca比值变化。电子探针图谱和LA-ICP-MS结果表明，Globigerinoides橡胶中存在高Mg含量和高Mg/Ca比值的周期性条带，这可能是共生菌的结果。相比之下，Neogloboquadrina dutrei， Pulleniatina obliquiloculata和Globorotalia inflata表现出较厚的方解石层，Mg/Ca比较低，可能与方解石结壳有关。同时，较高的Mg/Ca比值可能与污染物有关，特别是壳表面的污染物。这些结果表明，有孔虫壳中Mg/Ca比值的变化不仅受周围海水温度的控制，还受其他因素的影响。利用这种方法，我们重建了过去~ 3000年来东北南海的Mg/Ca-SST。结果表明，重建的海温趋势与以前的区域记录一致，验证了方法的鲁棒性。该方法具有效率高、处理速度快、空间分辨率高、样本量少等优点，有望在未来得到广泛应用。

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引用次数: 0

An unexpected journey – the arctic deep-sea halicreatid trachymedusa Botrynema brucei ellinorae off Florida: a reassessment under an integrative taxonomic approach 意想不到的旅程——佛罗里达海域的北极深海盐藻：综合分类方法下的重新评估

IF 2.3 3区地球科学 Q2 OCEANOGRAPHY

Deep-Sea Research Part I-Oceanographic Research Papers

Pub Date : 2025-07-03 DOI: 10.1016/j.dsr.2025.104551

Javier Montenegro , Jessica Kolbusz , Yakufu Niyazi , Joan J. Soto-Angel , Aino Hosia , Allen G. Collins , Alan J. Jamieson , Dhugal J. Lindsay

The study of the trachymedusa Botrynema has a long history of research, encompassing over 120 years of exploration in the deep sea. Two distinct morphotypes are recognized within Botrynema: one with a characteristic apical knob and another without it. Both morphotypes are present in the subspecies B. brucei ellinorae, while only specimens with a knob are known for the remainder of B. brucei. Specimens with a knob have been reported across all oceans and latitudes, whereas specimens without a knob are only known from Arctic and Subarctic regions. In this study, we use historical records, molecular tools and phylogenetic analyses to challenge the widely accepted notion of a cosmopolitan distribution for B. brucei as traditionally understood. We propose a range expansion to the subtropical western Atlantic Ocean for B. brucei ellinorae based on molecular data and hypothesize the existence of a mesopelagic soft barrier in the North Atlantic region as a plausible explanation to emerging biogeographical patterns revealed in this study.

对粗口水母（trachymedusa Botrynema）的研究历史悠久，在深海中进行了120多年的探索。Botrynema有两种不同的形态：一种具有特征性的顶端旋钮，另一种没有。这两种形态都存在于布氏杆菌亚种ellinorae中，而其余的布氏杆菌只知道带有旋钮的标本。有旋钮的标本在所有海洋和纬度都有报道，而没有旋钮的标本仅在北极和亚北极地区已知。在这项研究中，我们使用历史记录、分子工具和系统发育分析来挑战被广泛接受的布氏杆菌世界分布的传统观念。基于分子数据，作者提出布氏杆菌的分布范围扩展到亚热带西大西洋，并假设北大西洋地区存在中上层软屏障，这是本研究揭示的新兴生物地理格局的合理解释。

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引用次数: 0

Constraining sulfur and iron cycling in seep systems: insights from authigenic pyrite signatures 渗漏系统中限制硫和铁循环：来自自生黄铁矿特征的见解

IF 2.3 3区地球科学 Q2 OCEANOGRAPHY

Deep-Sea Research Part I-Oceanographic Research Papers

Pub Date : 2025-07-02 DOI: 10.1016/j.dsr.2025.104552

Qinyi Zhang , Daidai Wu , Yanting Ling , Xuan Chen , Shengyi Mao , Jie Liu , Guangrong Jin

Seep activity has emerged as a critical area of research for understanding biotic communities and elemental cycling (e.g., carbon, sulfur and iron) in deep extreme environments. While previous studies have predominantly focused on sulfur isotopes in pyrite as a proxy for seep activity, recent advancements highlight the potential of iron isotopes as an additional indicator. However, the detailed mechanism of how sulfur and iron coupled in seep environment is still unclear and thus hamper the further constraint of seep activity by these two key elements. For this reason, the authors analyzed 25 samples from three sediment cores which are collected from seepage sites in the Taixinan Basin (core 973–4) and the Pearl River Mouth Basin (cores GG03 and Z22-3) in the Northern South China Sea. By using SEM-EDS analysis and in-situ sulfur (δ³⁴S) and iron (δ⁵⁶Fe) isotope measurements, also combining with results from previous studies, the evolution patterns of sulfur and iron in seep environments is explored. The δ³⁴S values of pyrite in core 973–4 range from −18.79 ‰ to 27.26 ‰, indicating a closed-system seep activity. In contrast, pyrite in cores GG03 and Z22-3 exhibit significantly negative δ³⁴S values (−49.75 ‰ to −46.29 ‰ and −53.88 ‰ to −37.11 ‰, respectively), characteristic of more open-system seep activities. Additionally, the δ⁵⁶Fe values of pyrite are consistently negative across all cores (−1.39 ‰ to −0.31 ‰ in core 973–4, −1.59 ‰ to −0.24 ‰ in core GG03, and −1.10 ‰ to −0.20 ‰ in core Z22-3), suggesting the absence of a heavy iron isotope pool. By integrating these findings with previous results, this study demonstrates that the δ⁵⁶Fe values of pyrite are influenced by the position of the sulfate-methane transition zone, diverse microbial reduction processes, and varying iron sources. Therefore, this study provides valuable data to decipher how coupled sulfur and iron evolving in seep environments by pyrite, enhancing the further understanding of elemental cycles in extreme settings.

渗漏活动已成为了解深层极端环境中生物群落和元素循环（如碳、硫和铁）的关键研究领域。虽然以前的研究主要集中在硫铁矿中的硫同位素作为渗漏活动的代理，但最近的进展强调了铁同位素作为附加指标的潜力。然而，硫和铁在渗流环境中耦合的具体机制尚不清楚，从而阻碍了这两个关键元素对渗流活动的进一步约束。为此，作者对南海北部台南盆地（973-4号）和珠江口盆地（GG03和Z22-3号）渗漏点3个沉积物岩心的25个样品进行了分析。通过SEM-EDS分析和原位硫（δ34S）和铁（δ56Fe）同位素测量，并结合前人研究结果，探讨了渗流环境中硫和铁的演化模式。974 - 4岩心黄铁矿的δ34S值在−18.79‰~ 27.26‰之间，显示出封闭体系的渗流活动。而GG03和Z22-3岩心黄铁矿δ34S值显著负（分别为- 49.75‰~ - 46.29‰和- 53.88‰~ - 37.11‰），具有较强的开放体系渗流活动特征。此外，黄铁矿的δ56Fe值在所有岩心中均为负（974 - 4为- 1.39‰~ - 0.31‰，GG03为- 1.59‰~ - 0.24‰，Z22-3为- 1.10‰~ - 0.20‰），表明不存在重铁同位素池。综合前人的研究结果，本文认为黄铁矿的δ56Fe值受硫酸盐-甲烷过渡带位置、不同微生物还原过程和不同铁源的影响。因此，本研究提供了有价值的数据来解释硫铁矿在渗漏环境中耦合的硫和铁是如何演化的，增强了对极端环境下元素循环的进一步理解。

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引用次数: 0

Deep-sea nemerteans collected along the Japan Trench and the southern Kuril-Kamchatka Trench onboard the R/V Hakuho-maru with descriptions of two new species in Hoplonemertea R/V Hakuho-maru号在日本海沟和南千岛-堪察加海沟收集的深海海参，描述了Hoplonemertea的两个新物种

IF 2.1 3区地球科学 Q2 OCEANOGRAPHY

Deep-Sea Research Part I-Oceanographic Research Papers

Pub Date : 2025-06-30 DOI: 10.1016/j.dsr.2025.104549

Jamael C. Abato , Hiroshi Kajihara

A total of 80 nemertean specimens, representing 30 putative species, were obtained from the trawled material collected along the Japan Trench (JT) and southern Kuril-Kamchatka Trench (KKT) during the KH-22-8 and KH-23-5 cruises of the R/V Hakuho-maru in October 2022 and September 2023, respectively. Samples were collected from the 24 stations along these trenches at depths ranging from 2007 to 7654 m. Molecular and morphological analyses revealed nine species of Palaeonemertea (one in Carininidae, eight in Tubulanidae), seven species of Pilidiophora (six in Lineidae, one in Valenciinidae), and 14 species of Hoplonemertea (six Monostilifera, eight Polystilifera). All palaeonemerteans, six pilidiophorans, and eight hoplonemerteans represented species that are highly likely undescribed and distinct from species known in deep-sea environments globally in the last decade. Two new hadal hoplonemerteans were described in this study: Nemertovema kojimai sp. nov. in JT at 6211 m, and Profundonemertes hakuhoae gen. et sp. nov., found in JT and southern KKT at depths of 6807–7654 m. The phylogeny of the 30 species, including the two newly described, was analyzed using 16S, 18S, and 28S ribosomal RNA, cytochrome c oxidase subunit I (COI), and histone H3 genes. Nemertovema kojimai sp. nov. is closely related to Nemertovema norenburgi Chernyshev and Polyakova, 2019, while Profundonemertes hakuhoae gen. et sp. nov. was nested within Oerstediina, sister to Abyssonemertes kajiharai Chernyshev and Polyakova, 2018a, but with low support. Four previously described species were also reported for the first time in Japanese waters: Baseodiscus profundus Kajihara, Abukawa and Chernyshev, 2022b, in southern KKT; Dinonemertes cf. arctica Korotkevich, 1977 in both trenches; N. norenburgi, in southern KKT; and Phallonemertes murrayi (Brinkmann, 1912), in both trenches as well. The genus Nemertovema Chernyshev and Polyakova, 2018a was reported for the first time in JT, represented by N. kojimai sp. nov. and one additional undescribed species. This study provided the first comprehensive survey of deep-sea nemertean diversity along JT and updated our understanding of species diversity in KKT.

对2022年10月和2023年9月“白虎丸”号在日本海沟（JT）和千岛-堪察加海沟（KKT）南部进行的KH-22-8和KH-23-5巡航中收集的拖网材料进行了研究，共获得了80个nemertea标本，代表30种推测物种。样品采集自这些海沟沿线的24个站点，深度从2007年至7654 m不等。分子和形态分析结果显示，其中古刺蝇属9种（刺蝇科1种，管蝇科8种），刺蝇属7种（刺蝇科6种，花莲科1种），刺蝇属14种（单刺蝇科6种，多刺蝇科8种）。所有的古生动物、6种栉水母和8种新生动物代表了极有可能未被描述的物种，与过去十年全球深海环境中已知的物种截然不同。本研究发现了两种新的潜生深尾虫，分别是在6211 m发现的Nemertovema kojimai sp. 11，以及在6807 ~ 7654 m发现的深尾虫和KKT南部发现的Profundonemertes hakuhoae gen. et sp. 11。利用16S、18S和28S核糖体RNA、细胞色素c氧化酶亚基I （COI）和组蛋白H3基因分析了包括新发现的两个物种在内的30个物种的系统发育。Nemertovema kojimai sp. 11与Nemertovema norenburgi Chernyshev和Polyakova（2019）亲缘关系密切，而Profundonemertes hakuhoae gen. et sp. 11与Abyssonemertes kajiharai Chernyshev和Polyakova （2018a）的姊妹物种Oerstediina嵌套，但支持度低。在日本海域首次报道的有4种：KKT南部的Baseodiscus profundus Kajihara， Abukawa和Chernyshev， 2022b；Dinonemertes cf. arctic Korotkevich， 1977年在两条海沟；N. norenburgi在KKT南部；和Phallonemertes murrayi (Brinkmann, 1912)，也在两条战壕中。在日本首次报道了Nemertovema Chernyshev和Polyakova属，2018a，以N. kojimai sp. 11 .为代表，另有1个未描述种。该研究首次提供了沿JT的深海水母多样性的全面调查，更新了我们对KKT物种多样性的认识。

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引用次数: 0

Microplastic accumulation visually and fluorescently undetectable within deepwater corals of the remote equatorial Pacific 在遥远的赤道太平洋的深水珊瑚中，肉眼和荧光检测不到的微塑料积累

IF 2.3 3区地球科学 Q2 OCEANOGRAPHY

Deep-Sea Research Part I-Oceanographic Research Papers

Pub Date : 2025-06-28 DOI: 10.1016/j.dsr.2025.104550

Maxwell S. Helmberger , Steven Auscavitch , Justin Linehan , Timothy M. Shank , Erik Cordes , Randi D. Rotjan

Microplastic abundance in aquatic environments is a well-established phenomena, with the potential to disrupt ecological processes, including food webs and vector diseases via contaminated water and sediments. With the call for increasing ocean protection in remote and deep-waters, it is important to establish baselines of relative contamination, and to identify whether or not there are places relatively free from microplastic impact. Deep-sea corals are heterotrophic ecosystem engineers that have the potential to capture and ingest microplastic particles. In this study, we asked whether or not deep-sea corals in humanly remote, fully-protected, locations demonstrate evidence of microplastic ingestion using visual and fluorescence-enabled techniques. We found no strong evidence for microplastic accumulation. Despite these specific results, maintaining plastic-free environments in remote deep-sea systems will benefit from increased protections that limit or prevent anthropogenic activities. As such, open ocean and deep-water marine protected areas should consider including decreased pollution risk among their potential benefits.

水生环境中的微塑料丰度是一个公认的现象，有可能通过受污染的水和沉积物破坏生态过程，包括食物网和病媒疾病。随着人们呼吁加强对偏远和深海海洋的保护，建立相对污染的基线，并确定是否有相对不受微塑料影响的地方是很重要的。深海珊瑚是异养生态系统工程师，具有捕获和摄入微塑料颗粒的潜力。在这项研究中，我们询问了在人类偏远、完全受保护的地方的深海珊瑚是否使用视觉和荧光激活技术证明了微塑料摄入的证据。我们没有发现微塑料积累的有力证据。尽管有这些具体的结果，但在偏远的深海系统中保持无塑料环境将受益于限制或防止人为活动的保护措施的增加。因此，公海和深水海洋保护区应考虑将减少污染风险纳入其潜在利益之中。

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引用次数: 0

Evidence of vertical stratification in marine environments: insights from passive acoustic monitoring in French Polynesia 海洋环境中垂直分层的证据：来自法属波利尼西亚被动声学监测的见解

IF 2.3 3区地球科学 Q2 OCEANOGRAPHY

Deep-Sea Research Part I-Oceanographic Research Papers

Pub Date : 2025-06-21 DOI: 10.1016/j.dsr.2025.104548

Xavier Raick , Mélanie Vendrame , David Lecchini , Éric Parmentier

The stratification of species distribution in marine environments is well-documented, reflecting the influence of depth-related factors such as light availability, temperature, pressure, and habitat structure on the organization of marine communities. This study aimed to determine whether this stratification can also be highlighted using Passive Acoustic Monitoring (PAM), a technique proven effective in the study of various marine habitats. Sounds were recorded at 300 m in July 2022 off Moorea Island (French Polynesia) using a SNAP acoustic recorder. These data were compared to both those collected at shallower depths at Moorea Island (20, 60, and 120 m) and to data from other Polynesian islands obtained during a previous, non-concurrent study. Fish sounds in the recordings were manually identified. Richness and abundance of sounds from 20 m to 300 m depth were compared to assess whether fish communities in the altiphotic reef, upper mesophotic reef, lower mesophotic reef, and rariphotic zone could be distinguished based on the sounds they produce. Comparisons between zones over a 24-h period revealed for the first time the existence of acoustic stratification, with a fourfold decrease in species richness, from the altiphotic reef to the rariphotic zone, along with a general decline in sound abundance. However, this general pattern was not uniform in terms of abundance throughout the day, as sound abundance increased with depth at dusk from 950 sounds per hour at 20 m to 3600 at 300 m. It further confirms that diel activity patterns were also evident in light-deprived zones. This first exploration of vertical acoustic stratification based on fish sounds highlights the undeniable contribution of PAM to studies on the ecology of deep-sea communities.

海洋环境中物种分布的分层现象已被广泛研究，反映了光照、温度、压力和生境结构等与深度相关的因素对海洋群落组织的影响。这项研究旨在确定这种分层是否也可以使用被动声学监测（PAM）来强调，这是一种在各种海洋栖息地研究中被证明有效的技术。2022年7月，使用SNAP声学记录器在Moorea岛（法属波利尼西亚）附近300米处记录了声音。这些数据与Moorea岛较浅深度（20、60和120米）收集的数据以及之前非同步研究中从其他波利尼西亚岛屿获得的数据进行了比较。录音中的鱼声是人工识别的。通过比较20 m至300 m深度的声音丰富度和丰度，评估高光礁、中光礁上部、中光礁下部和疏光区的鱼类群落是否可以根据它们发出的声音进行区分。在24小时的区域间比较首次揭示了声分层的存在，从高光礁到疏光礁，物种丰富度减少了四倍，同时声丰度也普遍下降。然而，这种总体模式在一天中的丰度方面并不均匀，因为黄昏时声音丰度随着深度的增加而增加，从每小时20米的950个声音增加到每小时300米的3600个声音。它进一步证实，在光照不足的地区，昼夜活动模式也很明显。这一基于鱼类声音的垂直声学分层的首次探索突出了PAM对深海群落生态学研究的不可否认的贡献。

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引用次数: 0

Modeling of the isotope (δ18O, δ2H) composition and salinity of the seawater surface layer in polar regions: Application for the East and European arctic 极地海水表层同位素（δ18O, δ2H）组成和盐度的模拟：在东欧和欧洲北极的应用

IF 2.3 3区地球科学 Q2 OCEANOGRAPHY

Deep-Sea Research Part I-Oceanographic Research Papers

Pub Date : 2025-06-18 DOI: 10.1016/j.dsr.2025.104547

E.O. Dubinina, S.A. Kossova, Yu.N. Chizhova, A.S. Avdeenko

The surface sea water salinity and isotope (δ¹⁸O, δ²H) composition in polar regions are determined by the balance between freshening and freezing-related processes. Due to sea ice formation and its melting, the relation between the salinity and δ¹⁸O(δ²H) values does not correspond entirely to an additive process. We propose the dynamic model of surface layer (DMSL), which considers the fluxes corresponding to the freshening, freezing, and sea ice melting in order to describe the δ¹⁸O(δ²H)–salinity and δ¹⁸O–δ²H relations in Arctic seawater. The DMSL shows that the slope in the δ–salinity space is a complex function of melting and freezing fluxes, freshwater flux, salinity, and isotope composition of marine and freshwater endmembers. The model can be applied to salinity and isotope signatures both for any whole water region and for single water samples. The testing of the DMSL was done for water areas covered with different freezing–melting activity, located both in shelf areas influenced of continental runoff and in areas isolated from it. The data used for test calculations were obtained for surface (0–15 m) seawater collected in the Eastern and European Arctic in 2017, 2018, and 2021 (70°–82.7° N, and −4° W to 168° E) at the end of ice-free seasons. The calculations show that the model is capable of adequately estimating both the isotope signature of fresh water and the ratio of the main fluxes that form the surface layer: freshening, modification, and the contribution from melting sea ice.

极地地区表层海水盐度和同位素（δ18O, δ2H）组成由与新鲜和冻结有关的过程之间的平衡决定。由于海冰的形成和融化，盐度与δ18O（δ2H）值之间的关系并不完全符合加性过程。为了描述北极海水的δ18O(δ2H) -盐度关系和δ18O -δ2H关系，提出了考虑海冰新鲜、冻结和融化对应通量的表层动力学模型（DMSL）。DMSL表明，δ -盐度空间的斜率是融化和冻结通量、淡水通量、盐度以及海洋和淡水端元同位素组成的复杂函数。该模型可以应用于任何整个水域和单个水样的盐度和同位素特征。对DMSL的测试是在不同冻融活动覆盖的水域进行的，这些水域既位于受大陆径流影响的大陆架地区，也位于与大陆径流隔绝的地区。用于测试计算的数据是在2017年、2018年和2021年（70°-82.7°N， - 4°W至168°E）无冰季节结束时，在北极东部和欧洲收集的表面（0-15 m）海水中获得的。计算表明，该模式能够充分估计淡水的同位素特征和形成表层的主要通量的比率：新鲜、变质和海冰融化的贡献。

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引用次数: 0

Bacterial community characterization and relationship in the gut of deep-sea holothurians and sediment from the Northern Indian Ocean 北印度洋深海海棠肠道细菌群落特征及其与沉积物的关系

IF 2.3 3区地球科学 Q2 OCEANOGRAPHY

Deep-Sea Research Part I-Oceanographic Research Papers

Pub Date : 2025-06-18 DOI: 10.1016/j.dsr.2025.104546

Xinlong Li , Anning Mou , Yue Dong , Jing Mo , Xiaomei Liao , Xiao Wang , Zongling Wang , Xuelei Zhang , Qinzeng Xu

Sea cucumbers, widely distributed benthic invertebrates in diverse deep-sea habitats, rely on their gut bacterial communities for essential functions including energy metabolism, biological adaptation, and health. However, the gut bacterial community of deep-sea holothurians in the Indian Ocean remains poorly understood. We used 16S rRNA gene sequencing to characterize bacterial communities in the guts of sea cucumbers and surrounding sediments from two distinct regions of the northern Indian Ocean: the Ninety-East Ridge and the Arabian Sea Basin. This study investigates the composition, diversity, predicted functions, co-occurrence networks, and assembly processes of gut bacterial communities. Alpha diversity of gut bacterial communities did not differ significantly between the two regions. Based on principal coordinate analysis, the bacterial communities of gut formed a distinct cluster from the sediment communities. Actinobacteriota, Proteobacteria, Firmicutes, Chloroflexi, and Bacteroidota were the dominant phyla in both gut and sediment bacterial communities. In the Ninety-East Ridge, the gut microbial network exhibited a higher proportion of positive correlation than the sediment network, suggesting a greater potential for cooperative interactions. Compared to sediment communities, functional predictions indicated that gut communities were enriched in metabolic pathways, including those for amino acid, glycan, vitamin, and lipid metabolism. Stochastic processes were predominant in gut bacterial community assembly, whereas deterministic processes dominated in sediment bacterial communities. This study provides critical insights into the gut microbiota of deep-sea holothurians, advancing our understanding of microbial ecology in extreme marine environments.

海参是广泛分布于不同深海栖息地的底栖无脊椎动物，它们依靠肠道细菌群落来实现能量代谢、生物适应和健康等基本功能。然而，人们对印度洋深海全息鱼的肠道细菌群落知之甚少。我们使用16S rRNA基因测序来表征来自北印度洋两个不同区域的海参内脏和周围沉积物中的细菌群落：九十东脊和阿拉伯海盆地。本研究探讨了肠道细菌群落的组成、多样性、预测功能、共生网络和组装过程。两个地区肠道细菌群落的α多样性无显著差异。基于主坐标分析，肠道细菌群落与沉积物群落形成了明显的集群。放线菌门、变形菌门、厚壁菌门、绿菌门和拟杆菌门是肠道和沉积物细菌群落的优势门。在90 east Ridge，肠道微生物网络表现出比沉积物网络更高的正相关比例，表明更大的合作相互作用潜力。与沉积物群落相比，功能预测表明肠道群落在代谢途径中丰富，包括氨基酸、聚糖、维生素和脂质代谢途径。随机过程在肠道细菌群落组装中占主导地位，而确定性过程在沉积物细菌群落中占主导地位。这项研究为深海全息鱼的肠道微生物群提供了重要的见解，促进了我们对极端海洋环境下微生物生态的理解。

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引用次数: 0