Frontiers in Marine Science最新文献

{"title":"Stakeholder participation and crisis- responsive strategies in the Mediterranean blue bioeconomy-insights from Lebanon under Co-Evolve4BG project","authors":"Nahed Msayleb, Nada Mallah Boustani, Sana Abidib, Khouloud Athiman, Béchir Bejaoui","doi":"10.3389/fmars.2025.1618637","DOIUrl":"https://doi.org/10.3389/fmars.2025.1618637","url":null,"abstract":"IntroductionThis study investigates the long-term impacts of health emergencies—specifically the COVID-19 pandemic—on coastal tourism systems across the Mediterranean, with a particular focus on the Batroun pilot site in Lebanon. Coastal areas are especially vulnerable to systemic disruptions due to their dependence on tourism, ecological fragility, and governance fragmentation. Understanding how crises like COVID-19 reshape tourism dynamics is critical for advancing sustainable and resilient development within the blue bioeconomy framework.MethodsWe adopted a participatory research approach involving multi-stakeholder workshops, focus groups, and SWOT analyses. The Co-Evolve4BG Toolkit, a participatory evaluation instrument, was applied to assess the sustainability performance of Batroun's coastal tourism sector across environmental, economic, and governance dimensions. Thresholds and indicator scoring were co-developed with local actors and experts to reflect contextual realities.ResultsFindings revealed both systemic vulnerabilities and adaptive capacities. Batroun demonstrated relative strengths in public engagement, wastewater infrastructure, and cultural asset preservation. However, significant weaknesses emerged in pollution management, marine habitat protection, and institutional coordination. The COVID-19 pandemic acted as a stress test, highlighting the fragility of current systems but also catalyzing shifts toward digital tourism, circular economy initiatives, and decentralized decision-making.DiscussionThe Co-Evolve4BG Toolkit proved to be an effective mechanism for benchmarking sustainability and co-developing locally grounded action plans. Insights from the Batroun case emphasize the importance of participatory governance and integrated coastal management in building long-term resilience. We recommend the adoption of standardized health protocols, diversification of tourism models, and improved inter-institutional coordination at the regional level. These findings contribute to a replicable model for aligning ecological preservation with crisis-responsive tourism planning in Mediterranean coastal areas.","PeriodicalId":12479,"journal":{"name":"Frontiers in Marine Science","volume":"6 1","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144769914","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A novel method for distinguishing different algal blooms in the East China Sea via geostationary ocean color satellite observations","authors":"Min Zhao, Hao Li, Xuan Zhang, Xiaosong Ding, Fang Gong","doi":"10.3389/fmars.2025.1549711","DOIUrl":"https://doi.org/10.3389/fmars.2025.1549711","url":null,"abstract":"IntroductionDinoflagellate and diatom blooms are the most frequent marine ecological disasters in the Yangtze River estuary (YRE) and adjacent areas of the East China Sea (ECS). Distinguishing between these bloom types is essential for accurate monitoring and effective mitigation.MethodsTo investigate the physiological differences between bloom types, algal culture experiments were conducted to quantify variations in fluorescence quantum yield (φ) between dinoflagellates and diatoms during the growth phase. Using insights from the experiments, an identification and classification method for harmful algal blooms (HABs) was developed based on Geostationary Ocean Color Imager-II (GOCI-II) data. The method incorporates the difference in remote sensing reflectance (Rrs) between the fluorescence peak and baseline bands and establishes a φ-based classification threshold.ResultsValidation of GOCI-II Level-2 products showed that fluorescence-band Rrs products have high accuracy and strong correlation with in situ measurements. A threshold of φ = 0.014 was proposed to distinguish dinoflagellate from diatom blooms. The derived methods were successfully applied to GOCI-II imagery, enabling precise detection and classification of HABs in ECS waters.DiscussionThe proposed approach demonstrated strong capability for monitoring the spatial distribution and evolution of HABs. It provides a reliable technique for distinguishing bloom types using geostationary satellite data, offering valuable support for marine environmental management and mitigation efforts.","PeriodicalId":12479,"journal":{"name":"Frontiers in Marine Science","volume":"6 1","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144769917","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Predicting the environmental and socio-economic impacts of displaced fishing effort from a hypothetical highly protected marine area, located in English inshore waters","authors":"Laura A. Reeves, Melanie Hartley, James E. Stewart, Sarah Clark, Lauren Parkhouse, Duncan Vaughan","doi":"10.3389/fmars.2025.1601392","DOIUrl":"https://doi.org/10.3389/fmars.2025.1601392","url":null,"abstract":"In response to the Benyon review the UK Government introduced three Highly Protected Marine Areas (HPMAs), adding to the 178 Marine protected areas (MPAs) already designated in English waters. All extractive, destructive and depositional activities are prohibited within HPMAs to promote ecosystem recovery. However, it is a requirement of the designation process to consider the socio-economic impacts of the placement of a HPMA. There are many marine sectors competing for space in English waters, therefore displacing all damaging or disturbing activities occurring within newly designated HPMAs could further exacerbate this conflict. One key marine sector that is vulnerable to displacement from HPMAs is commercial fishing. Although a template to assess displacement has been developed, this template has not yet been applied. Therefore, this study aims to bridge this gap; applying a full displacement assessment to a Hypothetical HPMA (HypHPMA, 25km<jats:sup>2</jats:sup>), located within English inshore waters. This study investigates the extent to which commercial fishing vessels use the HypHPMA and potential reductions in catch (kg) and gross revenue changes (£) resulting from their displacement following hypothetical designation, using the R package VMStools. In addition, the habitat type and sensitivity within the HypHPMA and surrounding areas were analysed to highlight sensitive areas now protected by the HypHPMA or surrounding areas that may be more sensitive to fishing displacement. Our method allows fine spatial and temporal scales of socioeconomic analysis which can identify fleet and individual vessel vulnerabilities to displacement, alongside environmental analyses which quantify interactions between fishing gear and specific sensitive habitats. This method has wider utility than assessing displacement from HPMAs – it can be used to assess displacement resulting from other spatial management measures that restrict fishing activity.","PeriodicalId":12479,"journal":{"name":"Frontiers in Marine Science","volume":"30 1","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144769918","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The response of sedimentation regime to changes in upstream runoff, based on modelling scenarios analysis in Lingdingyang Estuary, China","authors":"Kanglin Chen","doi":"10.3389/fmars.2025.1553631","DOIUrl":"https://doi.org/10.3389/fmars.2025.1553631","url":null,"abstract":"In recent decades, episodic extreme meteorological events have occurred frequently worldwide. Extreme drought and flood events have notably impacted on the evolution of large estuarine deltas, affecting estuarine geomorphology, human settlements, and infrastructure. However, understanding the impact of these extreme hydrological events on estuarine geomorphic evolution is hampered due to the lack of knowledge about event-based hydrodynamic mechanisms. Lingdingyang Estuary (LE), which is located in the central and southern part of the Pearl River Delta, southern China and has large number of records in extreme drought and catastrophic flood disasters from 1960s to 2010s, provides an opportunity to examine variations in estuarine deposition regime caused by such extreme hydrological events. A state-of-the-art modeling tool (TELEMAC-2D), was used to simulate geomorphic evolution in six scenarios, accounting for low upstream runoff (i.e. extreme drought) and high upstream runoff (i.e. catastrophic flood). This results revealed that: i) The deposition regime in the Inner-lingdingyang Estuary (ILE) altered from an erosion pattern under low upstream runoff conditions to a strong deposition pattern under high upstream runoff conditions, where the scale of upstream runoff and sediment delivery was of key importance. The deposition regime shift may occur at the upstream runoff conditions between 3120 m3/s and 6831 m3/s. ii) Under high upstream runoff conditions, large area of strong depocenters were easily formed outside the outlets, causing flood discharge block from outlets, which increased the risk of flooding. iii) The most prominent morphologic response to changes in upstream runoff was observed in the Western Shoal, i.e. a medium erosion pattern in the MQ1scenario (Extreme drought) and an extremely strong deposition pattern in the MQ5 scenario (Normal drought). The geomorphic balance (i.e., the state of net deposition volume approaching equilibrium) between the Western Shoal and the Western Channel requires critical consideration. iv) The sudden and substantial sedimentation was detected in the navigation channels, i.e. a net deposition volume of 1.22×106 m3 in the Eastern Channel under catastrophic flood conditions. During catastrophic flood, bathymetric monitoring should be implemented to guide mitigation measures, such as emergency necessary dredging operations. Finally, large-scale sand mining should be avoided in the whole Middle Shoal owing to its limited sediment deposition capacity (For example, the net deposition volume in the Middle shoal was found to be less than 10% of that in the Western Shoal and 65% of that in the Eastern Shoal under catastrophic flood). However, appropriate sand mining scheme can be performed in the Eastern Shoal due to the net deposition pattern under upstream various hydrological conditions. My findings are valuable to improve the scientific comprehensive management of LE and promote the high-quality development of ","PeriodicalId":12479,"journal":{"name":"Frontiers in Marine Science","volume":"58 1","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-08-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144769913","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The importance of fauna-mediated sediment O2 consumption in the NGOM hypoxic zone","authors":"Hannah Beck, Kanchan Maiti","doi":"10.3389/fmars.2025.1532999","DOIUrl":"https://doi.org/10.3389/fmars.2025.1532999","url":null,"abstract":"The northern Gulf of Mexico (NGOM) coastal shelf adjacent to the Mississippi and Atchafalaya rivers system experiences strong seasonal hypoxia in the late summer and coupled physical-biological models suggest that hypoxia formation in the NGOM is sensitive to benthic biogeochemical processes. However, the processes driving sediment oxygen consumption and their relationship to bottom oxygen concentration remain enigmatic. This study for the first time concurrently measured <jats:italic>in situ</jats:italic> total oxygen uptake (TOU) and diffusive oxygen uptake (DOU) during two different hypoxia seasons. The relatively large DOU: TOU ratio of 0.33 ± 0.07 observed during this study suggests more significant benthic infauna community activity driving oxygen fluxes than previously thought. Future hypoxia models for this region should consider the role of infaunal-mediated oxygen consumption in biogeochemical variables.","PeriodicalId":12479,"journal":{"name":"Frontiers in Marine Science","volume":"37 1","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144763443","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"OptWake-YOLO: a lightweight and efficient ship wake detection model based on optical remote sensing images","authors":"Runxi Qiu, Nan Bi, Chaoyue Yin","doi":"10.3389/fmars.2025.1624323","DOIUrl":"https://doi.org/10.3389/fmars.2025.1624323","url":null,"abstract":"IntroductionShip wakes exhibit more distinctive characteristics than vessels themselves, making wake detection more feasible than direct ship detection. However, challenges persist due to sea surface interference, meteorological conditions, and coastal structures, while practical applications demand lightweight models with fast detection speeds.MethodsWe propose OptWake-YOLO, a lightweight ship wake detection model with three key innovations: A RepConv-based RCEA module in the Backbone combining efficient layer aggregation with reparameterization to enhance feature extraction. An Adaptive Dynamic Feature Fusion Network (ADFFN) in the Neck integrating channel attention with Dynamic Upsampling (Dysample). A Shared Lightweight Object Detection Head (SLODH) using parameter sharing and Group Normalization.ResultsExperiments on the SWIM dataset show OptWake-YOLO improves mAP50 by 1.5% (to 93.2%) and mAP50-95 by 2.9% (to 66.5%) compared to YOLOv11n, while reducing parameters by 40.7% (to 1.6M) and computation by 25.8% (to 4.9 GFLOPs), maintaining 303 FPS speed.DiscussionThe model demonstrates superior performance in complex maritime conditions through: RCEA's multi-branch feature extraction. ADFFN's adaptive multi-scale fusion. SLODH's efficient detection architecture. Ablation studies confirm each component's contribution to balancing accuracy and efficiency for real-time wake detection.","PeriodicalId":12479,"journal":{"name":"Frontiers in Marine Science","volume":"9 1","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144755971","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Quantitative assessment of coastal geomorphological and ecological damage risks: a case study of Sheyang coast","authors":"Dong Liang, Na Gao, Mingli Zhao, Mianrun Chen, Dongling Li, Haobing Cao, Zhaoyuan Zhang, Huamei Huang, Huaguo Zhang","doi":"10.3389/fmars.2025.1635902","DOIUrl":"https://doi.org/10.3389/fmars.2025.1635902","url":null,"abstract":"As critical zones of land–sea interaction, coastal areas serve as core regions for dense populations, economic development, and sustainable social progress. However, coastal erosion poses a significant challenge for China. Current risk management practices often rely on subjective judgment and lack standardized, quantifiable frameworks that integrate both subjective and objective perspectives. This study aims to develop a comprehensive classification framework for coastal degradation risk. By integrating the Analytic Hierarchy Process (AHP) and Criteria Importance Through Intercriteria Correlation (CRITIC) method using game theory, this framework effectively combines expert insights with empirical evidence. Six key indicators were collected for Sheyang coast over the past two decades, including shoreline change rate, nearshore mean wave height, nearshore mean current velocity, salt marsh vegetation area, mudflat area, and coastal slope. Based on the combined weights, coastal damage risk values were calculated. By leveraging the cloud model, critical thresholds were systematically identified to differentiate five risk levels—ranging from accretion to severe erosion—through a comprehensive assessment of shoreline siltation, shoreline stability, shoreline erosion accompanied by salt marsh vegetation disappearance, and steep slope formation with near-complete mudflat loss. This approach integrates multi-dimensional coastal parameters to establish a scientific framework for risk classification, enabling precise distinction between gradual sediment accumulation and catastrophic erosive degradation. The study reveals that the hydrodynamic conditions of Sheyang coast has gradually shifted from tide-dominated to wave-dominated, indicating a significant intensification of wave action in the region. The geomorphology evolved from wide tidal flats to steep erosional features, with a marked cumulative effect of coastal degradation, reflected in the escalation of risk level from level 2 to level 5. The proposed framework exhibits notable enhancements in both accuracy and adaptability, offering robust scientific support for targeted coastal zone management strategies. It not only elevates the precision of risk identification across dynamic coastal environments but also advances the methodological frontiers of coastal risk assessment.","PeriodicalId":12479,"journal":{"name":"Frontiers in Marine Science","volume":"723 1","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144763444","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Spatiotemporal characteristics and mechanisms of upper water exchange between the Arabian Sea and the Bay of Bengal in the North Indian Ocean","authors":"Defu Zheng, Junru Guo, Yanzhao Fu, Jun Song, Yu Cai","doi":"10.3389/fmars.2025.1610528","DOIUrl":"https://doi.org/10.3389/fmars.2025.1610528","url":null,"abstract":"The distribution of upper water masses and water exchange processes in the Arabian Sea and Bay of Bengal have important implications for the dynamics, thermal structure, and associated air-sea interactions in the North Indian Ocean. In this study, we apply the spectral clustering method to investigate the distribution patterns and exchange characteristics of Arabian Sea Water (ASW) and Bay of Bengal Water (BBW) under seasonal and interannual variability, with emphasis on the analysis of the spatiotemporal variations and control mechanisms of water fluxes in two main channel sections: the mouth of the Bay of Bengal (6° N) and the central equatorial seas (81° E). The results indicate that the eastward water flux driven by the Southwest Monsoon Current and Wyrtki jets averages 13.93±2.50 Sv (1 Sv = 10<jats:sup>6</jats:sup>/m<jats:sup>3</jats:sup>) in summer and autumn, and the distribution range of ASW can be extended to the north of 10° N in the Bay of Bengal during this period. The winter–spring BBW incursion into the region west of 73° E in the Arabian Sea and the transport of the Northeast Monsoon Current reach 16.43±1.48 Sv, showing distinct seasonal changes. From 2001 to 2020, water fluxes across the Bay mouth and equatorial channels generally show a positive correlation. Affected by the monsoon transition process and the equatorial half-year Kelvin wave, water flux changes exhibit distinct half-year and one-year cycles. The time series of low salinity water transport anomalies and Dipole Mode Index (DMI) in the Bay mouth and equatorial region are negatively correlated (–0.30 and –0.42), indicating that water exchange is also moderated by Indian Ocean Dipole (IOD) events on the interannual scale. The equatorial region exhibits greater sensitivity to IOD events, reflecting a more complex 2–3 year cycle in water flux variations. These findings highlight the effectiveness of the spectral clustering method in revealing the spatiotemporal patterns of water masses, which is important for understanding the ocean circulation system and associated climate variability in the North Indian Ocean.","PeriodicalId":12479,"journal":{"name":"Frontiers in Marine Science","volume":"26 1","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144755964","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A novel reinforcement learning framework-based path planning algorithm for unmanned surface vehicle","authors":"Jianhui Mou, Bo Shi, Bo Wang, Chengcheng Yu, Yangwei Wang, Fusheng Zhong, Li Zheng, Jian Wang, Junjie Li","doi":"10.3389/fmars.2025.1641093","DOIUrl":"https://doi.org/10.3389/fmars.2025.1641093","url":null,"abstract":"Unmanned surface vehicles (USVs) nowadays have been widely used in ocean observation missions, helping researchers to monitor climate change, collect environmental data, and observe marine ecosystem processes. However, path planning for USVs often faces several inherent difficulties during ocean observation missions: high dependence on environmental information, long convergence time, and low-quality generated paths. To solve these problems, this article proposes a novel artificial potential field-heuristic reward-averaging deep Q-network (APF-RADQN) framework-based path planning algorithm, aiming at finding optimal paths for USVs. First, the USV path planning is modeled as a Markov decision process (MDP). Second, a comprehensive reward function incorporating artificial potential field (APF) inspiration is designed to guide the USV to reach the target region. Subsequently, an optimized deep neural network with a reward-averaging strategy is constructed to effectively enhance the learning and convergence speed of the algorithm, thus further improving the global search capability and interface performance of USV path planning. In addition, the Bezier curve is applied to make the generated path more feasible. Finally, the effectiveness of the proposed algorithm is verified by comparing it with the DQN, A*, and APF algorithms in simulation experiments. Simulation results demonstrate that the APF-RADQN improves the interface ability and path quality, significantly enhancing the USV navigation safety and ocean observation mission operation efficiency.","PeriodicalId":12479,"journal":{"name":"Frontiers in Marine Science","volume":"42 1","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144763396","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Characteristics and distribution of surface sediments in the Central East China Sea shelf","authors":"Li Jinduo","doi":"10.3389/fmars.2025.1631365","DOIUrl":"https://doi.org/10.3389/fmars.2025.1631365","url":null,"abstract":"Based on grain-size analysis of the surface sediments on the central East China Sea (ECS) shelf, the spatial distribution, depositional settings, and transport patterns of these sediments were investigated in 2022. The results show that the study area can be divided into four Subareas: the nearshore clayey-silt or silt-dominated muddy deposition Subarea (Subarea I), the inner shelf silty-clay-dominated muddy deposition Subarea (Subarea II), the inner and outer shelf transition zone sand-silt-clay or clayey-sand-dominated mixed deposition Subarea (Subarea III), and the outer shelf sandy deposition Subarea (Subarea IV). Typical sediment grain size frequency curves and cumulative frequency curves reflect the sediment differentiation in Subareas I and II, as well as the sediment mixing and modification in Subareas III and IV. The spatial distribution of the sediments is affected by the hydrodynamic and environmental conditions. The main components of the surface sediments in this area are Yangtze River-derived terrigenous clasts. The contents of the sand, silt, and clay fractions obtained using the laser grain size analysis method were approximately 5% larger, 20% larger, and 25% smaller, respectively, than those acquired using the sieve and pipette analysis method, which was the reason that clayey-silt has been reported to occupy almost all of the muddy zone (Subareas I and II) in previous studies. Grain-size trend analysis images revealed the existence of generally north-to-south and west-to-east (i.e., coast-to-offshore) transport trends of the surface sediment in this area, indicating continuity of the provenance, environment, age, and genetic type of the sediments on the ECS shelf. Local regions exhibited different transport directions, which were influenced by the northward Taiwan Warm Current and upwelling. Mixed sediments experienced material redistribution and exchange with neighboring muddy and sandy deposits. The bidirectional northwest-southeast transport trends of some sandy sediments suggest a tidal genesis of the linear sand ridges and their effect on the sandy sediments in this region. Fine clay particles are spread over the entire ECS shelf, suggesting cross-shelf transport of modern fine-grained sediments.","PeriodicalId":12479,"journal":{"name":"Frontiers in Marine Science","volume":"26 1","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144763402","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}