Continental Shelf Research最新文献_第2页

Assessing spatiotemporal changes in the benthic habitats of the West Gironde Mud Patch through the analyses of surface sediments, benthic macrofauna and sediment profile images 通过表层沉积物、大型底栖动物和沉积物剖面图像分析，评估西吉伦特泥滩底栖生物栖息地的时空变化

IF 2.2 3区地球科学 Q2 OCEANOGRAPHY

Continental Shelf Research

Pub Date : 2026-04-01 Epub Date: 2025-12-31 DOI: 10.1016/j.csr.2025.105637

Bastien Lamarque , Bruno Deflandre , Sabine Schmidt , Nicolas Lavesque , Guillaume Bernard , Frédéric Garabetian , Christophe Fontanier , Sylvain Rigaud , Florent Grasso , Mélanie Diaz , Aldo Sottolichio , Dominique Poirier , Martin Danilo , Alicia Romero-Ramirez , Antoine Grémare

This work aims to refine the current assessment of spatiotemporal changes in the benthic habitats of the West Gironde Mud Patch. It follows a survey based on the analysis of surface sediment characteristics and benthic macrofauna composition at 5 stations located along a depth gradient, which was achieved between 2010 and 2018. The present work extends this observation period to 2021 and includes the indirect assessment of bioturbation through the analysis of sediment profile image characteristics. Temporal changes in surface sediment characteristics were essentially seasonal with strong increases in chloropigment concentrations in spring. Temporal changes in benthic macrofauna composition were mostly interannual with a major difference between 2010 and 2016–2021 currently attributed to the impact of a major physical disturbance during 2013–2014. In this study, extending the observation period shows that full recovery of benthic macrofauna composition had not yet been achieved by 2021. Sediment profile image characteristics (tube and organisms numbers, area of subsurface structures, oxic void depth and aRPD thickness) showed: (i) clear seasonal changes at the two deepest stations, mostly associated with a spring increase in tube numbers; and (ii) no significant difference between 2010 and 2016–2021, except at the deepest station. The discrepancy between benthic macrofauna composition and sediment profile image characteristics may result from differences in the recovery dynamics of benthic macrofauna composition and functionalities. Overall, results clearly call for a further extension of the WGMP observation period, which could consist in a yearly sampling at only two stations.

本研究旨在完善目前对西吉伦特泥沼底栖生物栖息地时空变化的评估。该研究是在2010年至2018年期间进行的一项调查基础上进行的，该调查基于对沿深度梯度分布的5个站点的地表沉积物特征和底栖大型动物组成的分析。目前的工作将这一观察期延长至2021年，并包括通过分析沉积物剖面图像特征来间接评估生物扰动。表层沉积物特征的时间变化基本上是季节性的，春季叶绿素浓度明显增加。底栖大型动物组成的时间变化主要是年际变化，2010年至2016-2021年之间的主要差异目前归因于2013-2014年主要物理干扰的影响。在本研究中，延长观察期表明，到2021年底栖大型动物组成尚未完全恢复。沉积物剖面图像特征（管和生物数量、地下结构面积、氧空洞深度和aRPD厚度）显示：(1)两个最深站的季节变化明显，主要与管数量的春季增加有关；（ii）除最深站外，2010年与2016-2021年无显著差异。底栖动物组成和沉积物剖面图像特征的差异可能是由于底栖动物组成和功能恢复动态的差异。总体而言，结果明确要求进一步延长WGMP观察期，可能包括每年只在两个站点采样。

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引用次数: 0

Phytoplankton assemblage in a cyclonic eddy confined to a coastal region of the Gulf of California 局限于加利福尼亚湾沿海地区的气旋涡旋中的浮游植物组合

IF 2.2 3区地球科学 Q2 OCEANOGRAPHY

Continental Shelf Research

Pub Date : 2026-04-01 Epub Date: 2026-01-26 DOI: 10.1016/j.csr.2026.105647

Elizabeth Durán-Campos , María Adela Monreal-Gómez , David Alberto Salas-de-León , Carlos Mauricio Torres-Martínez , Erik Coria-Monter

This study characterizes the phytoplankton assemblage within a cyclonic eddy confined in the Bay of La Paz, Gulf of California, integrating high-resolution hydrographic data and water samples collected in August 2017 complemented by satellite observations. The eddy featured a distinct cold core with elevated chlorophyll-a concentrations and supported a diverse phytoplankton community of 151 species, dominated by dinoflagellates (37,780 cells L⁻¹) and diatoms (35,780 cells L⁻¹). Notable taxa included Planktoniella sol, Pseudo-nitzschia subfraudulenta, Coscinodiscus asteromphalus, Protoperidinium punctulatum, Gyrodinium fusiforme, Protoperidinium robustum, Dictyocha fibula, Mesodinium rubrum, and Trichodesmium hildebrandtii. Horizontal distribution patterns revealed significant spatial heterogeneity, with species composition diverging between the eddy core and periphery in response to temperature and density gradients. Multivariate analysis identified temperature as the primary driver of community abundance. Furthermore, our findings suggest that a previously undocumented predator-prey dynamic between autotrophic and heterotrophic species may exert an additional influence on these patterns. These findings clarify how cyclonic eddies structure phytoplankton communities and provide critical insight into regional primary production, biogeography, and the distribution of species, some of which capable of forming harmful algal blooms.

本研究整合了2017年8月收集的高分辨率水文数据和水样，并辅以卫星观测，对加州湾拉巴斯湾气旋涡内的浮游植物组合进行了表征。涡旋具有明显的冷核特征，叶绿素-a浓度升高，支持151种多样的浮游植物群落，以鞭毛藻（37,780细胞L−1）和硅藻（35,780细胞L−1）为主。值得注意的分类群有：土壤浮游菌、亚假nitzschia subfraudulenta、星形盘尾螺、斑点原螺、fususiforme原螺、robustum原螺、Dictyocha fibula、Mesodinium rubrum和trichodesum hildebrandtii。水平分布表现出明显的空间异质性，物种组成随温度和密度梯度在涡旋核心和外围之间分化。多变量分析表明温度是群落丰度的主要驱动因素。此外，我们的研究结果表明，自养和异养物种之间的捕食者-猎物动态可能对这些模式产生额外的影响。这些发现阐明了气旋漩涡是如何构成浮游植物群落的，并为区域初级生产、生物地理和物种分布提供了重要的见解，其中一些物种能够形成有害的藻华。

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引用次数: 0

Developing a novel hybrid deep learning model for extratropical storm surge forecasting: A case in the Bohai Sea 一种新的混合深度学习模型在温带风暴潮预报中的应用——以渤海为例

IF 2.2 3区地球科学 Q2 OCEANOGRAPHY

Continental Shelf Research

Pub Date : 2026-02-01 Epub Date: 2025-11-25 DOI: 10.1016/j.csr.2025.105621

Zhicheng Zhu , Chengqing Ruan , Qinrong Liu , Zhifeng Wang , Jinsheng Qi

Storm surges pose persistent threats to coastal communities, endangering both human lives and infrastructure. While numerical models remain computationally intensive, artificial intelligence (AI) approaches have emerged as efficient alternatives for storm surge forecasting through their superior accuracy and computational efficiency. However, most existing site-specific forecasting models rely on single-point wind and pressure measurements, neglecting the role of regional wind fields that limit the precision of extratropical storm surge forecasts. To address this gap, we developed a novel end-to-end multi-station forecasting framework designed to establish mapping relationships between wind-pressure fields and observational stations. We employ a 3D UNet for spatiotemporal feature extraction from atmospheric fields, followed by Multilayer perceptrons (MLPs) to project these features onto multiple monitoring sites, with integrated Long Short-Term Memory (LSTM) networks for temporal sequence modeling. Validation experiments in the Bohai Sea demonstrate the model's dual capability in multiscale feature abstraction and temporal dynamics capturing, enabling comprehensive storm surge process forecasting. The proposed model achieves significant reductions across multiple error metrics in 48- and 72-h prediction tasks compared to baseline models. This study provides theoretical and practical insights for advancing multi-step storm surge forecasting systems and hybrid models for coastal disaster prevention, particularly for extratropical storm surge.

风暴潮对沿海社区构成持续威胁，危及人类生命和基础设施。虽然数值模型仍然是计算密集型的，但人工智能（AI）方法已经成为风暴潮预报的有效替代方案，因为它们具有卓越的准确性和计算效率。然而，大多数现有的特定站点预报模型依赖于单点风和压力测量，忽略了区域风场的作用，这限制了热带风暴潮预报的精度。为了解决这一差距，我们开发了一个新颖的端到端多站预测框架，旨在建立风压场和观测站之间的映射关系。我们使用3D UNet从大气场中提取时空特征，然后使用多层感知器（mlp）将这些特征投射到多个监测点，并使用集成的长短期记忆（LSTM）网络进行时间序列建模。渤海验证试验表明，该模型具有多尺度特征提取和时间动态捕获的双重能力，可实现风暴潮过程的综合预报。与基线模型相比，该模型在48和72小时预测任务中实现了多个误差指标的显著降低。该研究为推进多步骤风暴潮预报系统和混合模式的沿海灾害预防，特别是温带风暴潮预报提供了理论和实践见解。

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引用次数: 0

Natural desalination of marine-affected subsurface sediments and its impact on pH along the Western Bohai Sea coast 渤海西部沿海受海水影响的地下沉积物自然淡化及其对pH值的影响

IF 2.2 3区地球科学 Q2 OCEANOGRAPHY

Continental Shelf Research

Pub Date : 2026-02-01 Epub Date: 2025-11-24 DOI: 10.1016/j.csr.2025.105618

Lizhu Tian , Wei Guo , Rafaela Paulo Teixeira , Mingzheng Wen , Yunzhuang Hu , Fu Wang

In time defined by environmental transformation and anthropogenic pressure, understanding the natural geochemical evolution of coastal zones has never been more urgent. The Western Bohai Sea Coast (WBSC) offers a natural archive of significant land-sea evolution, comprising extensive subsurface deposits formed under marine influence during the progradation of the mid-to-late Holocene Yellow River delta. Over time, natural processes such as meteoric water infiltration and groundwater movement have altered the geochemical characteristics of these sediments. This study uses Electrical conductivity (EC) and pH measurements, combined with environmental indicators such as foraminiferal analysis, to explore the desalination of marine-affected subsurface sediments and its impact on pH along the WBSC. Under long-term percolation of meteoric water and groundwater, a spatially continuous low EC zone, or “desalination corridor”, has developed in marine-affected sediments. It narrows seaward from a broad range of active leaching to a restricted depth around the coastal groundwater table, and eventually to in the upper intertidal zone. Along with desalination, marine-affected sediments commonly develop high pH values, with the underlying mechanisms varying depending on distance from the coastline. In the central areas, the alkalinity increase is likely driven by the leaching of the Ca²⁺ in the sediments, whereas near the coast, the pronounced alkalization around the groundwater table is probably induced by geochemical reactions under high-Na⁺, low-flux groundwater conditions. These findings highlight a critical environmental dynamic between desalination and pH increase, with implications for soil health, agricultural viability, and ecosystem functioning in coastal regions.

在环境变化和人为压力所限定的时间内，了解海岸带的自然地球化学演化从未像现在这样迫切。渤海西岸是全新世中晚期黄河三角洲沉积过程中受海洋影响形成的大量地下沉积物，是一个重要的陆-海演化的天然档案。随着时间的推移，诸如大气水渗透和地下水运动等自然过程改变了这些沉积物的地球化学特征。本研究利用电导率（EC）和pH值测量，结合有孔虫分析等环境指标，探索受海洋影响的地下沉积物的淡化及其对WBSC沿线pH值的影响。在大气降水和地下水的长期渗透作用下，受海洋影响的沉积物中形成了一个空间连续的低EC区，即“海水淡化走廊”。它缩小了向海的范围，从广泛的主动浸出到沿海地下水位周围的有限深度，最终到潮间带的上部。随着海水淡化，受海洋影响的沉积物通常会产生高pH值，其潜在机制因与海岸线的距离而异。在中部地区，碱度增加可能是由沉积物中Ca2+的淋溶驱动的，而在海岸附近，地下水位周围明显的碱化可能是由高na +、低通量地下水条件下的地球化学反应引起的。这些发现突出了海水淡化与pH值增加之间的关键环境动态关系，对沿海地区的土壤健康、农业生存能力和生态系统功能都有影响。

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引用次数: 0

Drivers of nutrient dynamics and chlorophyll-a variability: The role of freshwater input, upwelling, and tropical cyclones near Saint Martin's Island, Bangladesh 营养动态和叶绿素-a变率的驱动因素：孟加拉国圣马丁岛附近淡水输入、上升流和热带气旋的作用

IF 2.2 3区地球科学 Q2 OCEANOGRAPHY

Continental Shelf Research

Pub Date : 2026-02-01 Epub Date: 2025-12-12 DOI: 10.1016/j.csr.2025.105624

Mohammad Sadman Alam , Subrata Sarker , Nabanita Das , Shashowti Chowdhury Riya , Myung Hwangbo , Jongsun Kim

The Bay of Bengal (BoB) receives significant amounts of discharge from river runoff as the largest delta in the world, which affects the dynamic of coastal and estuarine systems. Thus, Saint Martin Island (SMI), located in the northeastern part of the BoB, faces a significant influx of sediments and numerous contaminants from upstream sources, which are affecting the biogeochemistry of SMI. It is hypothesized that both river influx and frequent tropical cyclones that occur in the BoB significantly influence the coastal ecosystem of the Island. Therefore, to understand the coastal ecosystem of SMI, the spatiotemporal variability of nutrients and chl-a (July 2022–June 2023) was explored. This study identified the northeast (NE) monsoon as an important season for primary productivity with the concentration of chl-a, inorganic nitrogen, phosphate, and silicate as 1.03 μg L-1, 64.09 μmol L-1, 3.86 μmol L-1, 86.17 μmol L-1, respectively. Seasonal and regional nutrient ratios were near-Redfield (N:P:Si ≈ 17–18:1:17–18), with modest monsoonal shifts and comparatively stronger N-Si supply toward the estuary. The correlation of rain, wind stress, river discharge, Ekman transport, salinity, nutrients, temperature, chl-a, and dissolved oxygen was evaluated by using a coast-normal wind and Ekman framework together with structural equation modelling (SEM). SEM indicated positive effects of discharge, rainfall, and Ekman transport on nutrients. Especially, chl-a was positively associated with salinity and DIP and negatively with DIN and temperature, while the direct Ekman-to-chl-a path was not significant. After the cyclone Sitrang, the mixed-layer was deepened (∼1.33 m), and a narrowed temperature-salinity pattern toward higher salinity, DIP, and DIN increases in the upper 50 m was observed. During the southwest (SW) monsoon, river discharge dominated nutrient supply, whereas the reduced rainfall was correlated with wind- and eddy-assisted vertical inputs that sustained productivity near the estuary during the NE monsoon. This study highlighted monthly horizontal and vertical variations of hydrological parameters and their interrelationship with algal growth and nutrient dynamics.

作为世界上最大的三角洲，孟加拉湾（BoB）接收了大量的河流径流，这影响了沿海和河口系统的动态。因此，位于BoB东北部的圣马丁岛（SMI）面临着来自上游来源的大量沉积物和大量污染物的涌入，这些污染物正在影响SMI的生物地球化学。假设河流涌入和频繁发生的热带气旋都对岛屿的沿海生态系统产生了重大影响。因此，为了解SMI沿海生态系统，研究了营养物和chl-a的时空变化（2022年7月- 2023年6月）。东北季风是重要的初级生产力季节，chl-a、无机氮、磷酸盐和硅酸盐的浓度分别为1.03、64.09、3.86和86.17 μmol L-1。季节和区域养分比接近红场（N:P:Si≈17-18:1:17-18），季风变化不大，向河口的N-Si供应相对较强。利用海岸正常风和Ekman框架，结合结构方程模型（SEM），评估了降雨、风应力、河流流量、Ekman运输、盐度、营养物质、温度、chl-a和溶解氧的相关性。扫描电镜显示，流量、降雨和Ekman运输对养分有积极影响。其中，chl-a与盐度和DIP呈正相关，与DIN和温度呈负相关，而ekman -chl-a的直接通路不显著。气旋Sitrang后，混合层加深（约1.33 m），在上层50 m处，温度-盐度呈窄化趋势，盐度较高，DIP和DIN增加。在西南季风期间，河流流量主导了养分供应，而降水减少与东北季风期间维持河口附近生产力的风和涡旋辅助垂直输入有关。该研究强调了水文参数的月度水平和垂直变化及其与藻类生长和营养动态的相互关系。

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引用次数: 0

Fossil evidence for accelerated growth and shorter lifespan in the harvested bivalve Arca noae in the Adriatic Sea 亚得里亚海收获的双壳类动物Arca noae生长加速和寿命缩短的化石证据

IF 2.2 3区地球科学 Q2 OCEANOGRAPHY

Continental Shelf Research

Pub Date : 2026-02-01 Epub Date: 2025-12-18 DOI: 10.1016/j.csr.2025.105628

Rafał Nawrot , Melita Peharda , Saskia Macharia , Hana Uvanović , Adam Tomašových , Martin Zuschin

Changes in life history of marine species in response to harvesting and human-induced environmental changes are frequently observed in modern ecosystems, but the true magnitude of these shifts is difficult to evaluate without robust information on the pre-impact state of the affected populations. The edible bivalve Noah's Ark shell (Arca noae L.) was extensively harvested in the eastern Adriatic Sea in the late 19th and early 20th century until its fishery collapsed following mass mortality in the late 1940s. The lack of data on growth parameters of this species prior to that event biases our understanding of its life history and complicates establishing sustainable levels of harvesting. To provide a baseline for assessment of the current state of populations of A. noae in the Adriatic Sea, we compared growth rates and lifespan, estimated based on annual shell growth lines, between live-collected individuals and fossil (Holocene) specimens sampled from sediment cores. The maximum age observed in our modern samples was 35 years whereas the ontogenetically oldest fossil specimen lived for at least 85 years, extending the longest recorded lifespan for the Arcidae family by over three decades. Our results indicate that individuals of A. noae collected in the 21st century grow faster and have much shorter lifespan compared to their Holocene counterparts, suggesting that intensive harvesting in the past combined with increasing water temperatures and eutrophication of the northern Adriatic Sea had a significant impact on the population dynamics of this species.

在现代生态系统中，经常观察到海洋物种生命史因捕捞和人为引起的环境变化而发生的变化，但如果没有关于受影响种群受影响前状态的可靠信息，很难评估这些变化的真实幅度。19世纪末和20世纪初，可食用的双壳类诺亚方舟贝壳在亚得里亚海东部被广泛捕捞，直到20世纪40年代末，它的渔业因大规模死亡而崩溃。在那次事件之前，缺乏关于该物种生长参数的数据，使我们对其生活史的理解产生偏差，并使建立可持续的收获水平变得复杂。为了给亚得里亚海noae种群现状的评估提供一个基线，我们比较了在亚得里亚海收集的活的个体和从沉积物岩心中采集的化石（全新世）标本的生长速率和寿命，这是根据年壳生长线估计的。我们在现代样本中观察到的最大年龄是35岁，而最古老的个体化石标本至少活了85岁，将Arcidae家族记录的最长寿命延长了30多年。结果表明，与全新世相比，21世纪采集的noae个体的生长速度更快，寿命更短，这表明过去的密集采集加上亚得里亚海北部水温升高和富营养化对该物种的种群动态产生了重大影响。

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引用次数: 0

Macrofauna of soft sediments associated with cold seeps from the offshore Sinú basin, Colombian Caribbean 来自哥伦比亚加勒比海Sinú近海盆地的与冷渗漏有关的软沉积物的大型动物群

IF 2.2 3区地球科学 Q2 OCEANOGRAPHY

Continental Shelf Research

Pub Date : 2026-02-01 Epub Date: 2025-11-24 DOI: 10.1016/j.csr.2025.105619

Maria Isabel Aguilar Pérez , Paula Andrea Zapata Ramirez , Aaron Micallef

Cold seeps in the offshore Sinú Basin, Colombian Caribbean, sustain macrofaunal communities in soft sediments, driven by chemosynthetic energy from methane and sulfide. This study investigated macroinfaunal assemblages at 19 stations within a seepage field off the Gulf of Morrosquillo, at depths of 47–166 m. Sampling utilized a Box Corer and ROV assessments, with stations categorized by seepage signal intensity (High, Medium, Low, Blank) and sediment type (Mud, Sandy Mud, Muddy Sand, Sand). A total of 1414 individuals from 115 taxa across four phyla (Annelida, Arthropoda, Mollusca, Echinodermata) were recorded, with Annelida (33 %) and Crustacea (39 %) dominating. Key families, including Ampeliscidae (9.3 %), Syllidae (5.1 %), and Maldanidae (4.5 %), exhibited patchy distributions influenced by sediment grain size and geological features such as mud volcanoes and faults. Ecological indices revealed high richness (Margalef: 5.8), diversity (Shannon-Weaver: 4.1), and uniformity (Pielou: 0.9), indicating a resilient ecosystem. Cluster and ordination analyses identified two main station groups based on mud content (Group 1: 93–99 %; Group 2: 40–55 %), with significant dissimilarities driven by families like Syllidae and Caridea (ANOSIM R = 0.849, p = 0.1 %). BIO-ENV analysis highlighted mud percentage as the primary environmental driver (Rho = 0.747), with salinity, temperature, and depth as secondary factors. Methane concentration showed a moderate influence (Rho = 0.517). These findings underscore the role of sediment texture and local geomorphology in structuring macrofaunal communities, with implications for understanding cold seep biodiversity in the Caribbean.

在哥伦比亚加勒比海地区Sinú离岸盆地的冷渗漏，在甲烷和硫化物的化学合成能量的驱动下，维持着软沉积物中的大型动物群落。本研究调查了Morrosquillo湾外47-166米深度的渗漏场内19个站点的大型动物群落。采样使用了Box cover和ROV评估，并根据渗漏信号强度（高、中、低、空白）和沉积物类型（泥、砂泥、泥沙、砂）对站点进行了分类。共记录到4门（环节动物、节肢动物、软体动物、棘皮动物）115个类群1414只，其中环节动物占33%，甲壳动物占39%。主要科（包括Ampeliscidae（9.3%）、Syllidae（5.1%）和Maldanidae(4.5%)）受沉积物粒度和泥火山、断层等地质特征的影响，呈斑块状分布。生态指数显示丰富度（Margalef: 5.8）、多样性（Shannon-Weaver: 4.1）和均匀度（Pielou: 0.9）较高，表明生态系统具有弹性。聚类和排序分析根据泥含量确定了两个主要的站点组（组1:93 - 99%；组2:40 - 55%），其中Syllidae和Caridea等科的差异显著（ANOSIM R = 0.849, p = 0.1%）。BIO-ENV分析强调，泥浆含量是主要的环境驱动因素（Rho = 0.747），盐度、温度和深度是次要因素。甲烷浓度的影响中等（Rho = 0.517）。这些发现强调了沉积物质地和当地地貌在构建大型动物群落中的作用，对理解加勒比地区的冷渗生物多样性具有重要意义。

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引用次数: 0

Prevalence of epibiotic ciliates on crustacean zooplankton in the Southeastern Arabian Sea 阿拉伯海东南部甲壳类浮游动物表面纤毛虫的流行

IF 2.2 3区地球科学 Q2 OCEANOGRAPHY

Continental Shelf Research

Pub Date : 2026-02-01 Epub Date: 2025-11-19 DOI: 10.1016/j.csr.2025.105607

Aishwarya Purushothaman , Sanu V. Francis , Lathika Cicily Thomas , K.B. Padmakumar

Ciliate-zooplankton associations in marine ecosystems remain largely understudied, despite their ecological significance within the planktonic community. In this study, copepods and ostracods were identified as the primary hosts for various ciliate epibionts, Lecanophryella satyanandani, Paracineta karunakarani, Acineta karamani, Acineta euchaetae, Ephelota coronata and Ephelota crustaceorum, along the coastal and offshore waters of the southeastern Arabian Sea. Detailed observations on the morphology, distribution, host specificity, sex preference, and attachment sites of the ciliate epibionts enhance existing knowledge. Female zooplankton were more frequently colonised than males, and epibiotic associations were more pronounced in offshore regions, except for ostracod-ciliate interactions, which were more prevalent in coastal waters. Temperature, salinity, and nutrients were found to be the key physicochemical factors influencing the epibiotic associations. The relationship between ciliate colonisation and chlorophyll a concentrations revealed that oligotrophic offshore waters of the southeastern Arabian Sea supported higher incidences of epibiotic associations. The study provides the first comprehensive dataset on the zooplankton-ciliate association across the entire southeastern Arabian Sea, contributing valuable insights into animal interactions in marine systems.

尽管纤毛虫-浮游动物在海洋生态系统中的生态意义重大，但它们之间的联系在很大程度上仍未得到充分的研究。本研究确定了桡足类和介形虫是阿拉伯海东南部沿海和近海多种毛虫附生生物Lecanophryella satyanandani、Paracineta karunakarani、Acineta karamani、Acineta euchaetae、Ephelota coronata和Ephelota甲壳类的主要寄主。对纤毛虫附生体的形态、分布、寄主特异性、性别偏好和附着部位的详细观察增强了现有的知识。雌性浮游动物比雄性浮游动物更频繁地被定植，除了介形虫-纤毛虫的相互作用在沿海水域更为普遍外，表观生物的关联在近海地区更为明显。温度、盐度和营养物质是影响表观生物关联的关键理化因素。纤毛虫定殖与叶绿素a浓度之间的关系表明，阿拉伯海东南部的贫营养近海水域支持较高的表观生物关联发生率。该研究提供了第一个关于整个阿拉伯海东南部浮游动物-毛虫关系的综合数据集，为海洋系统中动物相互作用提供了有价值的见解。

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引用次数: 0

Interplay of habitat heterogeneity and sampling gear in structuring nekton communities: Insights from niche overlap and biomass spectra in a mangrove estuary 生境异质性和采样装置在构建浮游生物群落中的相互作用：来自红树林河口生态位重叠和生物量光谱的见解

IF 2.2 3区地球科学 Q2 OCEANOGRAPHY

Continental Shelf Research

Pub Date : 2026-02-01 Epub Date: 2025-12-24 DOI: 10.1016/j.csr.2025.105629

Yuming Wang , Xinyi Gao , Jiakang Liu , Yutong Ma , Miaozhi Lin , Tuohui Ye , Jianxiang Feng

To obtain the relationship between mangrove habitats and fisheries production, a seasonal investigation of the status of nekton communities in the Zhangjiang estuary was conducted using gillnet and unbaited centipede cage from September 2020 to May 2021. The index of relative importance (IRI), Shannon-Wiener diversity index (H′), Pielou evenness index (J’), and Margalef richness index (D) were used to study the dominant species and species diversity of the nekton community. A total of 83 species of nektons were identified in the survey, including 55 species of fish belonging to 11 orders and 22 families, mainly warm-water demersal fishes, accounting for 66.27 % of the total species, and 28 species of crustaceans belonging to 2 orders and 9 families, accounting for 33.73 % of the total species. The results of the NMDS analysis revealed that catches varied seasonally, that the BPUE of catches per unit effort in autumn was significantly higher than in other seasons. The spatial niche overlaps of nekton were generally high and seasonal variations in the biomass size spectra were noticeable. The species pairs with niche overlap over 0.3 (Qik>0.3) caught by gill nets and cages represented 73.3 % and 86.81 % of the total pairs, respectively. In general, the resources of nektons in Zhangjiang Estuary were relatively low, and the spatial distribution was uniform. The season was the main factor affecting the resources and community structure of nektons.

为了解红树林生境与渔业生产的关系，于2020年9月至2021年5月，采用刺网和无饵蜈蚣笼对张江口红树林浮游生物群落进行了季节性调查。采用相对重要性指数（IRI）、Shannon-Wiener多样性指数（H’）、Pielou均匀度指数（J’）和Margalef丰富度指数(D)研究了浮游生物群落的优势种和物种多样性。调查共发现浮游动物83种，其中鱼类55种，隶属于11目22科，以温水底栖鱼类为主，占总种数的66.27%；甲壳类28种，隶属于2目9科，占总种数的33.73%。NMDS分析结果显示，渔获量存在季节差异，秋季单位努力渔获量的BPUE显著高于其他季节。浮游生物的空间生态位重叠度普遍较高，生物量大小谱的季节变化明显。刺网和网箱捕获的生态位重叠度大于0.3 （Qik>0.3）的种对分别占73.3%和86.81%。总体而言，张江口内浮游生物资源相对较少，空间分布较为均匀。季节是影响线虫资源和群落结构的主要因素。

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引用次数: 0

Hydrodynamics of the inner shelf east of the Amazon River mouth 亚马逊河口以东内陆架的流体动力学

IF 2.2 3区地球科学 Q2 OCEANOGRAPHY

Continental Shelf Research

Pub Date : 2026-02-01 Epub Date: 2025-12-19 DOI: 10.1016/j.csr.2025.105626

Carlos A.F. Schettini , Nils E. Asp

The hydrodynamics of the inner shelf east of the Amazon River mouth in the Southeastern Amazon Coastal Zone (SACZ) are examined based on 1.5 years of observations of wind and currents. A meteorological station was established onshore to record the wind data, while an acoustic Doppler current profiler was moored offshore at a depth of 22 m. This is the first observational dataset of such length and quality east of the Amazon River mouth off SACZ. The results reveal two primary modes of hydrodynamic variation associated with the zonal migration of the Intertropical Convergence Zone (ITCZ), which significantly influences the regional wind regime. The first mode, termed “wet”, occurs when the ITCZ shifts southward, leading to brief periods (hours to days) of wind relaxation. In contrast, the second mode, referred to as “dry”, is characterized by a northward displacement of the ITCZ, resulting in more intense and consistent wind conditions. Throughout the year, the hydrodynamics are predominantly controlled by semidiurnal meso (neap) and macro (spring) tidal regimes, accounting for more than 98 % of the variance in cross-shelf currents and more than 90 % of longitudinal currents. This dominance is especially pronounced during the dry mode. In the wet mode, the current regime exhibits greater vertical variability, with low-frequency currents near the surface potentially dominating (>80 %). These low-frequency currents are associated with periods of wind relaxation and the eastward advance of the Amazon River plume. During the dry mode, low-frequency currents are influenced primarily by wind action, with a secondary contribution from the synodic modulation of tidal amplitude.

基于近1.5年的风、流观测资料，对亚马孙河东南海岸带（SACZ）亚马孙河河口以东的内陆架的水动力进行了研究。在陆地上建立了一个气象站来记录风的数据，同时在22米深的海上系泊了一个声学多普勒电流廓线仪。这是第一个在亚马孙河河口以东的SACZ外如此长度和质量的观测数据集。研究结果揭示了与热带辐合带纬向迁移相关的两种主要水动力变化模式，它们对区域风况有显著影响。第一种模式，称为“湿”，发生在ITCZ向南移动时，导致短暂的风松弛期（数小时到数天）。相比之下，第二种模式，称为“干”模式，其特征是ITCZ向北移动，导致更强烈和持续的风条件。全年的水动力主要受半日中观（小潮）和宏观（春季）潮势控制，占跨陆架流变化的98%以上，占纵向流变化的90%以上。这种优势在干燥模式下尤为明显。在湿模式下，电流状态表现出更大的垂直变化，近地表的低频电流可能占主导地位（> 80%）。这些低频洋流与风减弱和亚马逊河羽流向东推进的时期有关。在干模期间，低频洋流主要受风作用的影响，其次是潮汐振幅的synodic调制。

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引用次数: 0