Journal of Marine Systems最新文献_第5页

Lagrangian dispersion in the Red River plume region, Northeast Vietnam, from drifter observations and modeling 越南东北部红河羽流区域的拉格朗日色散，来自漂流观测和模拟

IF 2.5 3区地球科学 Q2 GEOSCIENCES, MULTIDISCIPLINARY

Journal of Marine Systems

Pub Date : 2025-10-02 DOI: 10.1016/j.jmarsys.2025.104143

Alexei Sentchev , Thinh Nguyen-Duc , Stefano Berti , Nadia K. Ayoub , Vu Duy Vinh

The transport and spatial distribution of materials within river plumes and neighboring waters are strongly influenced by the plume morphology and fronts bounding the plume area. Thus, identifying locations of plume fronts and assessing frontal mixing activity is particularly important for understanding the spatial distribution of biogeochemical tracers and the connectivity between source (river mouth) and offshore regions. Statistical properties of horizontal dispersion in the Red River (RR) plume region were obtained from drifter experiments, conducted in the Gulf of Tonkin during summer 2022, and also from realistic numerical modeling. Adopting a Lagrangian perspective, a method is proposed to characterize the RR plume morphology based on the extraction of Lagrangian Coherent Structures (LCS) from the surface flow field using Finite-Size Lyapunov Exponents (FSLE). Maxima of the attracting FSLE field (FSLE ridge lines) enabled us to identify zones of current convergence and shear in the flow, which are essential for characterizing the dynamics associated with plumes and mapping the fronts delimiting them. It became clear that the body of the RR plume is formed by the individual river plumes of the RR deltaic system. FSLE ridge lines allowed identification of the offshore expansion of individual plumes and revealed a variety of forms, semi-circular or hook-like filaments, characterizing the plume shape. The ballistic regime of dispersion was found inside the plume region, with the dominant direction perpendicular to the coastal flow direction revealing anisotropic shear dispersion. It was observed at scales of 0.3 to 3 km (submesoscale range), with a maximum value of 10–13 day⁻¹, as derived from the analysis of the scale dependent relative dispersion of real drifters. In model simulations, the relative dispersion appeared scale independent in the range below 2 km, indicating a significant effect of grid resolution on the model's representation of lateral mixing.

河流羽流和邻近水域内物质的运输和空间分布受到羽流形态和包围羽流区域的锋面的强烈影响。因此，确定地幔柱锋面的位置和评估锋面混合活动对于了解生物地球化学示踪剂的空间分布以及源（河口）和近海区域之间的连通性尤为重要。通过2022年夏季在东京湾进行的漂流实验和实际数值模拟，获得了红河（RR）羽流区域水平弥散的统计特性。采用拉格朗日视角，利用有限尺寸李雅普诺夫指数（FSLE）从地表流场提取拉格朗日相干结构（LCS），提出了一种表征RR羽流形态的方法。吸引FSLE场的极大值（FSLE脊线）使我们能够识别气流中的电流辐合和切变区域，这对于表征与羽流相关的动力学和绘制划定它们的锋面是必不可少的。很明显，RR羽流体是由RR三角洲体系的单个河流羽流形成的。FSLE脊线可以识别单个羽流的近海扩张，并揭示了各种形式，半圆形或钩状细丝，表征了羽流的形状。在羽流区域内发现弹道型弥散，主要方向垂直于海岸流动方向，表现出各向异性剪切弥散。观测尺度为0.3 ~ 3 km（亚中尺度范围），最大值为10-13天−1，这是根据实际漂流者的尺度相关相对分散分析得出的。在模式模拟中，在2 km以下的范围内，相对弥散与尺度无关，表明网格分辨率对模式的横向混合表示有显著影响。

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引用次数: 0

Zooplankton seasonal variability in Arctic fjord during cold and warm events – taxonomic and trait-based approaches (Kongsfjorden, Svalbard) 北极峡湾浮游动物在寒冷和温暖事件中的季节变化——分类和基于特征的方法（斯瓦尔巴群岛kongsjorden）

IF 2.5 3区地球科学 Q2 GEOSCIENCES, MULTIDISCIPLINARY

Journal of Marine Systems

Pub Date : 2025-10-01 DOI: 10.1016/j.jmarsys.2025.104144

Marta Gluchowska , Stig Falk-Petersen , Haakon Hop , Anna Olszewska , Wojciech Walkusz , Slawomir Kwaśniewski

Kongsfjorden, located on the west coast of Spitsbergen (79°N), lies at the boundary between Arctic and Atlantic water masses, making it an ideal site for studying the influence of environmental conditions on ecosystem dynamics and offering insights applicable to other Arctic regions. In this study, we describe the seasonal succession and interannual variability of the zooplankton community in Kongsfjorden in quantitative, taxonomic, and ecological terms, as observed during years with contrasting hydrographic conditions. The analysis is based on data collected in 2002, 2006, and 2007—years characterized by pronounced environmental differences, particularly in spring, with notable variation in seawater temperature and salinity. Zooplankton samples were collected from stations within the fjord and on the adjacent shelf using vertically stratified hauls with a Hydro-Bios Multi Plankton Sampler midi (180 μm mesh). Ecologically, the zooplankton community was analyzed using four traits—body size, feeding mode, spawning strategy, and transparency—allowing classification of 115 taxa into ten functional groups. Across all seasons, zooplankton biomass was consistently dominated by non-gelatinous, medium-sized, free-spawning forms. A clear seasonal shift in functional composition was observed, from current feeders in spring to ambush feeders in autumn, reflecting changes in food availability and trophic dynamics. Trait-based patterns proved more stable than taxonomic composition and more effectively captured key aspects of zooplankton functional roles in ecosystem processes, including trophic interactions, carbon export, and pelago–benthic coupling. Although the data reflect conditions from nearly two decades ago, they represent both cold and warm hydrographic states and remain ecologically relevant. Our findings highlight the sensitivity of Arctic zooplankton communities to early-season hydrography and bloom composition, and underscore the value of trait-based approaches for detecting structural shifts and anticipating ecosystem responses under ongoing Arctic Atlantification.

kongsjorden位于斯匹次卑尔根岛西海岸（北纬79°），位于北极和大西洋水团之间的边界，是研究环境条件对生态系统动态影响的理想场所，并提供适用于其他北极地区的见解。在本研究中，我们从数量、分类和生态的角度描述了在不同水文条件下Kongsfjorden浮游动物群落的季节演替和年际变化。该分析基于2002年、2006年和2007年收集的数据，这些年份的环境差异明显，特别是在春季，海水温度和盐度变化显著。采用Hydro-Bios Multi Plankton Sampler midi （180 μm目）垂直分层运输，在峡湾内和邻近大陆架上采集浮游动物样本。生态学上，利用体型、摄食方式、产卵策略和透明度4个特征对浮游动物群落进行了分析，并将115个类群划分为10个功能类群。在所有季节，浮游动物生物量始终以非凝胶状、中等大小、自由产卵的形式为主。观察到功能组成有明显的季节变化，从春季的当前摄食者到秋季的伏击摄食者，反映了食物供应和营养动态的变化。基于性状的模式被证明比分类组成更稳定，并且更有效地捕获了浮游动物在生态系统过程中的功能角色的关键方面，包括营养相互作用、碳输出和远洋-底栖耦合。虽然这些数据反映的是近20年前的情况，但它们代表了寒冷和温暖的水文状态，并且仍然具有生态相关性。我们的研究结果强调了北极浮游动物群落对早季水文和水华组成的敏感性，并强调了基于特征的方法在正在进行的北极大西洋化中检测结构变化和预测生态系统响应的价值。

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引用次数: 0

Spatiotemporal patterns of marine heatwaves in the Southern Ocean and their role in air-sea interaction 南大洋海洋热浪的时空格局及其在海气相互作用中的作用

IF 2.5 3区地球科学 Q2 GEOSCIENCES, MULTIDISCIPLINARY

Journal of Marine Systems

Pub Date : 2025-09-29 DOI: 10.1016/j.jmarsys.2025.104141

K. Gurumoorthi, Alvarinho J. Luis

Marine heatwaves (MHWs) are extended periods of abnormally warm ocean conditions in which temperature exceeds the 90th percentile threshold limit. While prior studies have mainly focused on regional trends, the Southern Ocean, particularly around Antarctica, has been relatively understudied despite experiencing considerable warming in recent decades. This study investigates MHWs in the Southern Ocean from 1982 to 2022, highlighting significant spatial and temporal variations in their frequency, intensity, and days. MHWs were found to be more frequent (0.4 events per decade) and intense north of 65°S, especially during the summer, with a marked rise in occurrence after 2008, coinciding with anthropogenic climate change and increasing sea surface temperatures (SST). The study also identifies the influence of climate patterns such as El Niño and the Indian Ocean Dipole (IOD) on MHWs intensity and frequency, particularly in the Ross Sea during spring and autumn. We analyzed the atmospheric impacts of significant MHWs in 2013. The 2013 MHW event serves as a key example of extreme subsurface warming, where temperatures reached 6.2 °C at 120 m depth, significantly increasing the region's heat content. This highlights how MHWs can transmit heat vertically, impacting both surface and deep ocean layers. The findings emphasize the complex interactions between ocean dynamics, and atmospheric conditions in determining MHWs patterns in the Southern Ocean, offering crucial insights for predicting the region's future responses to climate change.

海洋热浪（MHWs）是指温度超过90个百分位阈值限制的长时间异常温暖的海洋条件。虽然先前的研究主要集中在区域趋势上，但尽管近几十年来经历了相当大的变暖，但对南大洋，特别是南极洲周围的南大洋的研究相对不足。本研究调查了1982年至2022年南大洋的强震，突出了其频率、强度和天数的显著时空变化。在65°S以北，特别是夏季，强热带副热带气旋更为频繁（每10年0.4次），发生频率在2008年后显著上升，与人为气候变化和海表温度升高相一致。该研究还确定了厄尔尼诺Niño和印度洋偶极子（IOD）等气候模式对强震强度和频率的影响，特别是在春季和秋季的罗斯海。我们分析了2013年显著强震对大气的影响。2013年MHW事件是极端地下变暖的一个重要例子，在120米深处温度达到6.2°C，显著增加了该地区的热含量。这突出了MHWs如何垂直传播热量，影响海洋表层和深海层。这些发现强调了海洋动力学和大气条件之间复杂的相互作用在决定南大洋的mhw模式，为预测该地区未来对气候变化的反应提供了重要的见解。

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引用次数: 0

Evaluation and projection of Arctic sea ice transport through Fram Strait with emphasis on atmospheric multimodal responses 北极海冰通过弗拉姆海峡运输的评估和预测，重点是大气多模式响应

IF 2.5 3区地球科学 Q2 GEOSCIENCES, MULTIDISCIPLINARY

Journal of Marine Systems

Pub Date : 2025-09-26 DOI: 10.1016/j.jmarsys.2025.104139

Zhou Ye , Yu Zhang , Wenyun Guo , Changsheng Chen , Hailong Guo , Weizeng Shao , Deshuai Wang , Danya Xu , Yi Zhou

This study evaluates the historical (1988–2014) sea ice drift (SID), sea ice concentration (SIC), sea ice thickness (SIT), and associated sea ice volume transport (SIVT) from 12 CMIP6 models in Fram Strait based on multi-source reference datasets. In addition, a global ice-ocean coupled model based on the Finite Volume Community Ocean Model (Global-FVCOM), is included as a comparison. Both the simulated and reference SIVT show significant interannual variability, but inter-model spread exists. Compared to reference data, the CMIP6 models exhibit greater discrepancies than Global-FVCOM. The comprehensive assessment reveals notable performance differences among the models in simulating varying sea ice variables. Ensemble experiments, incorporating models with varying performance in simulating SIVT, demonstrate a decreasing trend in SIVT across all schemes under the SSP2–4.5 and SSP5–8.5 scenarios, with a more pronounced decline in the latter. Compared to the traditional multi-model mean scheme using all models, the scheme selecting six better-performing models through evaluation results of SIVT exhibits lower SIVT values and a slower decline. There are significant differences among the CMIP6 models regarding the dominant factors contributing to future SIVT variations. The largest number of models demonstrates a strong relationship between the dipole anomaly (DA) and sea ice transport, followed by those associated with the Arctic Oscillation (AO), while the fewest models show a significant connection to the Beaufort-Barents Oscillation (BBO). The choice of time period, whether by year or month, considerably influences the identification of dominant modes for sea ice transport.

基于多源参考数据，利用12个CMIP6模式，对福里姆海峡地区1988-2014年的海冰漂移（SID）、海冰浓度（SIC）、海冰厚度（SIT）和相关海冰体积输运（SIVT）进行了评估。此外，还采用了基于有限体积群落海洋模型（global - fvcom）的全球冰海耦合模型作为对比。模拟和参考SIVT均表现出显著的年际变化，但模式间存在差异。与参考数据相比，CMIP6模型比Global-FVCOM模型表现出更大的差异。综合评价表明，不同模式在模拟不同海冰变量方面存在显著差异。综上实验表明，在SSP2-4.5和SSP5-8.5情景下，所有方案的SIVT均呈下降趋势，其中SSP2-4.5和SSP5-8.5情景下SIVT下降更为明显。与使用所有模型的传统多模型均值方案相比，通过SIVT评价结果选择6个表现较好的模型的方案SIVT值更低，下降速度更慢。在影响未来SIVT变化的主要因素方面，CMIP6模式之间存在显著差异。最大数量的模式显示了偶极子异常（DA）和海冰运输之间的强烈关系，其次是与北极涛动（AO）相关的模式，而最少的模式显示了与波弗特-巴伦支涛动（BBO）的显著联系。时间段的选择，无论是按年还是按月，对海冰运输的主要模式的确定有很大的影响。

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引用次数: 0

Grain-size and geochemical evidence for sediment transport mechanisms in the northeastern part of the East Siberian Sea and on the adjacent continental slope 东西伯利亚海东北部及邻近大陆斜坡沉积物输运机制的粒度和地球化学证据

IF 2.5 3区地球科学 Q2 GEOSCIENCES, MULTIDISCIPLINARY

Journal of Marine Systems

Pub Date : 2025-09-26 DOI: 10.1016/j.jmarsys.2025.104140

Ekaterina Ovsepyan , Evgeniia Dorokhova , Yaroslav Ovsepyan , Ramiz Aliev , Young Keun Jin

Grain-size analyses, end-member modeling, X-ray fluorescence, and radionuclide activity measurements were conducted on sediment minicores collected from the middle-outer shelf of the East Siberian Sea (ESS) and the upper part of the adjacent continental slope to elucidate the sedimentation mechanisms in this poorly studied region. The grain-size data demonstrate that clayey silt and silt strongly dominate on the ESS shelf and the continental slope. In contrast, sandy silt has a patchy distribution. End-member modeling, applied here for the first time, indicates that sea ice (frazil and anchor ice) rafting, and nepheloid transport are the primary processes responsible for distributing sedimentary material across the ESS. The XRF data confirm the results of previous studies, reporting a predominantly lithogenic origin for ESS deposits. Combined grain size and geochemical records suggests that the shelf break area serves as a depocenter for fine silt particles, likely supplied by nepheloid flow, and represents the most productive area in the northeastern ESS. High sea surface productivity likely results from influence of nutrient-rich Pacific-derived waters, the upwelling of transformed Atlantic-derived waters, or a combination of both. The accumulation of the high amount of fine silt near the shelf break is suggested to be related to relatively calm bottom-water conditions, resulting from the potential interaction of the northward-flowing cross-shelf currents and episodic southward-moving compensatory flows. Wind direction is considered a key factor controlling the intensity of fine-grained material distribution by nepheloid flows and anchor ice across the ESS shelf. Sedimentation rates derived from the radionuclide activity measurements vary from 1.3 mm yr⁻¹ on the outer shelf to 1.0 mm yr⁻¹ on the upper continental slope.

对东西伯利亚海（ESS）中外陆架和邻近大陆斜坡上部的沉积物微粒进行了粒度分析、端元建模、x射线荧光和放射性核素活性测量，以阐明这一研究较少的地区的沉积机制。粒度数据表明，黏性粉砂质和粉砂质在陆架和陆坡上占主导地位。砂质粉砂则呈斑块状分布。本文首次应用的端元模型表明，海冰（巴西冰和锚冰）漂流和nepheloid运输是导致沉积物质在ESS中分布的主要过程。XRF数据证实了之前的研究结果，报告了ESS矿床的主要岩性成因。综合粒度和地球化学记录表明，陆架破碎区是细粉砂的沉积中心，可能是由泥砾石流供给的，是东北中生代最高产的地区。高海面生产力可能是由于营养丰富的太平洋源水的影响，或经过改造的大西洋源水的上涌，或两者兼而有之。陆架断裂带附近大量细粉砂的堆积与相对平静的底水条件有关，这是由向北流动的跨陆架洋流和向南移动的偶发补偿流的潜在相互作用造成的。风向被认为是控制星云流和锚冰在ESS陆架上细粒物质分布强度的关键因素。由放射性核素活度测量得出的沉积速率从外大陆架的1.3 mm yr - 1到上大陆斜坡的1.0 mm yr - 1不等。

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引用次数: 0

Dynamics of Total organic carbon: Partitioning, distribution and controlling processes in the Indian sector of the Southern Ocean during austral summer 总有机碳动力学：南大洋夏季印度板块的分配、分布和控制过程

IF 2.5 3区地球科学 Q2 GEOSCIENCES, MULTIDISCIPLINARY

Journal of Marine Systems

Pub Date : 2025-09-22 DOI: 10.1016/j.jmarsys.2025.104137

Melena A. Soares, V. Venkataramana, R.K. Mishra, P. Sabu, R.K. Naik, Manish Tiwari, N. Anilkumar, R. Mohan, K. Mahalinganathan

The Southern Ocean (SO) is a globally important region connecting the Pacific, Atlantic and Indian Oceans, having extreme seasonal changes and is crucial with regard to the carbon dynamics. Organic carbon plays a vital role in various biogeochemical processes and the carbon biological pump in the ocean. This study discusses the variability of total organic carbon (TOC) and its partitioning into particulate and dissolved fractions across the different fronts of the Indian sector of the Southern Ocean during two austral summers. A considerable interannual variation in the TOC distribution was noted, TOC concentration ranged from 84.4 to 127.8 μM in 2013 and from 76.3 to 121.2 μM in 2015, with considerable interannual variation in the TOC distribution. This study implied that the dominant phytoplankton community substantially contributed to the changes in composition and partitioning of organic carbon in the epipelagic waters and microbial respiration in the mesopelagic waters. Besides, the zooplankton community and its grazing effect influenced the organic carbon dynamics within the water column. Also, a significant correlation of total organic carbon with temperature, apparent oxygen utilisation and dissolved inorganic carbon, suggests the interplay of physical mixing processes like water mass intrusion and eddies. With biochemical responses altering the TOC distribution. Importantly, even small climate changes like warming in the SO can stimulate alterations in hydrographic processes, the food web structure and carbon pathways, impacting the fate of organic carbon in the oceanic ecosystem.

南大洋（SO）是连接太平洋、大西洋和印度洋的全球重要区域，具有极端的季节变化，对碳动态至关重要。有机碳在海洋的各种生物地球化学过程和碳生物泵中起着至关重要的作用。本研究讨论了两个南方夏季南大洋印度板块不同锋面上总有机碳（TOC）的变化及其颗粒和溶解组分的划分。TOC分布年际变化较大，2013年TOC浓度变化范围为84.4 ~ 127.8 μM， 2015年TOC浓度变化范围为76.3 ~ 121.2 μM， TOC分布年际变化较大。研究表明，浮游植物优势群落对上层水体有机碳组成和分配以及中上层水体微生物呼吸的变化起着重要作用。此外，浮游动物群落及其放牧效应影响了水柱内有机碳动态。此外，总有机碳与温度、表观氧利用率和溶解无机碳的显著相关性表明，水团入侵和漩涡等物理混合过程相互作用。生化反应改变了TOC的分布。重要的是，即使是像SO变暖这样的小气候变化也会刺激水文过程、食物网结构和碳途径的变化，影响海洋生态系统中有机碳的命运。

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引用次数: 0

Spatial and temporal distribution of Sthenoteuthis oualaniensis in the Northwest Indian Ocean during different life stages of cyclonic eddies 西北印度洋涡旋不同生命阶段瓦兰尼须鲸的时空分布

IF 2.5 3区地球科学 Q2 GEOSCIENCES, MULTIDISCIPLINARY

Journal of Marine Systems

Pub Date : 2025-09-18 DOI: 10.1016/j.jmarsys.2025.104138

Fu Yingyue , Wu Xiaoci , Jin Pengchao , Zhang Zhong , Xing Qinwang , Yu Wei

Mesoscale eddies, particularly cyclonic eddies (CEs), are known to influence the abundance and distribution of purpleback flying squid (Sthenoteuthis oualaniensis) resources in the northwest Indian Ocean. Sthenoteuthis oualaniensis is a short-lived species and is sensitive to environmental changes. The evolution of CEs is accompanied by structural and energetic transformations, exerting varying impacts on the local marine environment. However, the response of S. oualaniensis to these evolving CEs remains unclear. Therefore, this study analyzed the changes in basic eddy characteristics during CEs evolution and the environmental changes (sea surface temperature, chlorophyll-a concentration, and dissolved oxygen concentration at 150 m depth) driven by CEs. Combined with a habitat suitability index (HSI) model, the distribution of S. oualaniensis during the different life stages of CEs was analyzed. The results showed that the CEs experienced three stages: the early stage, the mature stage and the aged stage. At different stages, the parameters of CEs exhibited distinct distribution patterns. As the eddy evolved, the gravity center of S. oualaniensis abundance in latitude and longitude exhibited a movement trajectory similar to the eddy center. The environmental changes driven by this evolution process influenced the distribution of S. oualaniensis, and the maximum suitable habitat area was generated during the CEs mature stage. These results show that the evolution of CEs significantly affects the habitat distribution of S. oualaniensis in the northwest Indian Ocean.

中尺度涡旋，特别是气旋涡旋（CEs），是影响西北印度洋紫背飞乌贼资源丰富度和分布的重要因素。Sthenoteuthis wallaniensis是一种短命物种，对环境变化敏感。ce的演变伴随着结构和能量的转变，对当地海洋环境产生不同的影响。然而，S. oualaniensis对这些进化的ce的反应尚不清楚。因此，本研究分析了ce演化过程中基本涡旋特征的变化以及ce驱动的环境变化（海表温度、叶绿素-a浓度和150 m深度溶解氧浓度）。结合生境适宜性指数（HSI）模型，分析了华氏沙蚕在不同生活阶段的分布。结果表明，ce的生长经历了早期、成熟期和衰老期三个阶段。在不同阶段，ce参数呈现出不同的分布格局。随着涡旋的演化，南纬和经度丰度的重心呈现出与涡旋中心相似的运动轨迹。这一演化过程所驱动的环境变化影响了华氏沙蚕的分布，其最大适宜生境面积在华氏沙蚕成熟期形成。这些结果表明，印度洋西北海域的ce演化对S. oualaniensis的生境分布有显著影响。

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引用次数: 0

Coral bleaching occurrence and its relation to marine heatwave events in the Southwestern waters of South Sulawesi, Indonesia, as part of the Coral Triangle region 珊瑚三角区印度尼西亚南苏拉威西西南海域珊瑚白化事件及其与海洋热浪事件的关系

IF 2.5 3区地球科学 Q2 GEOSCIENCES, MULTIDISCIPLINARY

Journal of Marine Systems

Pub Date : 2025-09-12 DOI: 10.1016/j.jmarsys.2025.104136

Dian Noor Handiani , Nining Sari Ningsih , Erlin Beliyana

This study investigates the escalating threat of marine heatwaves (MHWs) to coral reef ecosystems in the southwestern waters of South Sulawesi, Indonesia. Based on four decades of data from 1982 to 2021, our analysis reveals a substantial increase in both the frequency and intensity of MHWs, with particularly severe events occurring in 2010, 2013, 2016, 2019, and 2020. The 2016 MHW was especially devastating, marked by extreme thermal stress and prolonged duration, reaching up to 215 days in the Lesser Sunda Islands. This event closely aligned with widespread Bleaching Alert Level 2 warnings in regions such as Lombok, indicating a high risk of coral mortality. The Coral Reef Health Index (CRHI) proved to be a valuable tool for reef assessment, showing strong positive correlations with coral cover (r = 0.83) and seagrass cover (r = 0.74), along with a strong negative correlation with rubble cover (r = −0.82). These results highlight the crucial role of reef structure and benthic composition in sustaining ecosystem health. In addition, the observed delay between peak MHW conditions and the occurrence of bleaching events emphasizes the need for real-time, high-resolution monitoring systems that integrate multiple observation methods. Our findings underscore the urgency of implementing comprehensive conservation strategies. These should include global actions to reduce ocean warming and targeted local efforts such as protecting reefs with high CRHI values, minimizing local stressors, and enhancing the effectiveness of marine protected areas. Future research should prioritize the integration of long-term field surveys with advanced remote sensing technologies and the inclusion of a wider range of oceanographic variables such as water quality and ocean acidification. Such approaches are essential for generating actionable data that support adaptive management and the sustained conservation of coral reef ecosystems.

本研究调查了海洋热浪（MHWs）对印度尼西亚南苏拉威西岛西南水域珊瑚礁生态系统的威胁。基于1982年至2021年40年的数据，我们的分析显示，mhw的频率和强度都大幅增加，特别严重的事件发生在2010年、2013年、2016年、2019年和2020年。2016年的MHW尤其具有破坏性，其特点是极端的热应力和持续时间长，在小巽他群岛长达215天。这一事件与龙目岛等地区广泛出现的白化预警2级密切相关，这表明珊瑚死亡的风险很高。珊瑚礁健康指数（CRHI）与珊瑚覆盖（r = 0.83）和海草覆盖（r = 0.74）呈强正相关，与碎石覆盖（r = - 0.82）呈强负相关，是一种有价值的珊瑚礁评估工具。这些结果强调了珊瑚礁结构和底栖生物组成在维持生态系统健康方面的关键作用。此外，观测到的MHW峰值条件与白化事件发生之间的延迟强调了对集成多种观测方法的实时、高分辨率监测系统的需求。我们的研究结果强调了实施综合保护策略的紧迫性。这些措施应包括减少海洋变暖的全球行动和有针对性的地方努力，如保护高CRHI值的珊瑚礁，尽量减少当地的压力因素，以及提高海洋保护区的有效性。今后的研究应优先考虑将长期实地调查与先进的遥感技术结合起来，并纳入更广泛的海洋学变量，如水质和海洋酸化。这些方法对于产生可操作的数据至关重要，这些数据支持适应性管理和珊瑚礁生态系统的持续养护。

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引用次数: 0

Rapid decline of nutrients in the subsurface of the East Sea (Japan Sea) over the past 28 years 近28年来，东海（日本海）海底营养物急剧减少

IF 2.5 3区地球科学 Q2 GEOSCIENCES, MULTIDISCIPLINARY

Journal of Marine Systems

Pub Date : 2025-09-08 DOI: 10.1016/j.jmarsys.2025.104135

Sojin Park , Guebuem Kim , SungHyun Nam , Joon-Soo Lee , In-Seong Han

A previous study suggested that the Northwest Pacific Ocean has experienced an approximately 25 % decline in nutrients in the subsurface (100–850 m), leading to a 50 % decline in the surface (0–100 m) over the past four decades (Kim et al., 2022). In this study, we observed a comparable 20 % decrease in nutrients in the East/Japan Sea (EJS) subsurface (200–500 m) from 1995 to 2022, despite its limited connection to the Northwest Pacific through shallow sills (<130 m). This subsurface trend appears to contribute to a 70 % decline in nutrients in the mixed layer (0–50 m) of the eastern EJS. In contrast, complex nutrient trends were observed in the western EJS surface (0–200 m), likely influenced by anthropogenic inputs. The significant nutrient decline in the EJS, which may alter its biological production and carbon cycle, provides further evidence of regional climate regime-shift feedbacks occurring in the North Pacific and other major subtropical gyres.

之前的一项研究表明，在过去的40年里，西北太平洋海底（100-850米）的营养物质减少了大约25%，导致表层（0-100米）的营养物质减少了50% （Kim et al., 2022）。在这项研究中，我们观察到，从1995年到2022年，东/日本海（EJS）地下（200-500米）的营养物质减少了20%，尽管它通过浅海与西北太平洋的连接有限（<；130米）。这一地下趋势似乎导致东部EJS混合层（0-50 m）营养物质减少70%。相比之下，在西部EJS表层（0-200 m）观察到复杂的营养趋势，可能受到人为输入的影响。EJS中显著的养分下降可能改变其生物生产和碳循环，这进一步证明了北太平洋和其他主要亚热带环流中发生的区域气候变化反馈。

引用次数: 0

Highly variable bottom water oxygen concentration in the shallow Arkona Basin (Baltic Sea) 波罗的海浅海Arkona盆地底部氧气浓度变化很大

IF 2.5 3区地球科学 Q2 GEOSCIENCES, MULTIDISCIPLINARY

Journal of Marine Systems

Pub Date : 2025-09-01 DOI: 10.1016/j.jmarsys.2025.104134

Joachim Kuss , Ulf Gräwe , Bronwyn Cahill , Volker Mohrholz , Michael Naumann , Robert Mars , Siegfried Krüger , Detlef E. Schulz-Bull , Joanna J. Waniek

Shallow western Baltic Sea waters show seasonal low oxygen concentrations in bottom waters from summer into early autumn. A record of hourly oxygen measured from 2012 to 2017 at a platform in the central Arkona Basin ascertained important developments of distinct short-term variability in bottom water oxygen concentration. Analysis of these years indicated that severe hypoxia of 0–2 mg L⁻¹ occurred in July with a duration between 0 and 10 h, in August between 0 and 61 h and in September again between 0 and 10 h. Using 4 mg L⁻¹ as the threshold, the ranking of the respective years from longest to shortest duration in hypoxic events showed 2012 (982 h) as the worst, followed by 2016 (854 h), 2013 (769 h), 2014 (659 h) and 2015 (351 h). The clear improvement in 2015 was caused by a Major Baltic Inflow that ventilated the system. Interpreting the drivers of short term hypoxia from the in situ measurements alone was difficult, as adequately resolved biogeochemical parameters were not measured. However, coincident three dimensional high resolution coupled hydrographic-biogeochemical modelling, reproduced the oxygen concentrations at the platform, and additionally revealed considerable spatial variability in the oxygen distribution in the area and its causes. Microbial degradation of organic matter in bottom waters was found to be the major oxygen consumption process with nitrification also contributing in some years. Recovery from seasonal periods of hypoxia is linked to the break-up of the seasonal thermocline or is caused by lateral transport of differently preformed oxygenated waters. The study demonstrates the utility of combining high resolution in situ observations with coincident biogeochemical modelling, as a powerful, integrated tool for monitoring and understanding drivers of short-term seasonal hypoxia.

从夏季到初秋，波罗的海西部浅海海底的氧浓度呈季节性低。2012年至2017年，在Arkona盆地中部的一个平台上测量的每小时氧气记录确定了底部水氧气浓度明显的短期变化的重要发展。这些年来的分析表明,严重缺氧的0 - 2毫克L−1与0之间的持续时间和发生在7月10 h,介于0和61 h和8月9月再次介于0和10 h。使用4毫克L−1作为阈值,相应的年的排名从2012年缺氧事件显示最短持续时间最长(982 h)最严重,其次是2016(854小时),2013(769小时),2014 (659 h)和2015 (351 h)。2015年的明显改善是由于波罗的海的主要流入给系统通风。由于没有测量到充分解决的生物地球化学参数，仅从原位测量来解释短期缺氧的驱动因素是困难的。然而，三维高分辨率水文-生物地球化学耦合模拟再现了台地的氧浓度，并揭示了该地区氧分布的空间变异性及其原因。海底有机物的微生物降解被发现是主要的耗氧过程，硝化作用在某些年份也有贡献。季节性缺氧期的恢复与季节性温跃层的破裂有关，或者是由不同预形成的含氧水的侧向输送引起的。该研究展示了高分辨率原位观测与同步生物地球化学模拟相结合的实用性，作为监测和理解短期季节性缺氧驱动因素的强大综合工具。

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