Frontiers in Marine Science最新文献

{"title":"The process of trace metals enrichment in pyrite under methane seepage in the northern South China Sea","authors":"Yanting Ling, Xuan Chen, Daidai Wu, Qinyi Zhang, Shengyi Mao, Guangrong Jin, Jie Liu, Haizhen Zhai, Chao Yang, Zheng Su, Nengyou Wu","doi":"10.3389/fmars.2025.1653453","DOIUrl":"https://doi.org/10.3389/fmars.2025.1653453","url":null,"abstract":"Pyrite is an important indicator of methane seepage. The effects of organic sulfate reduction (OSR) and sulfate-driven anaerobic oxidation of methane (SD-AOM) on the trace metals in pyrite have aroused interest; however, further studies about how these two pathways control the trace element patterns are still required. Therefore, we studied the geochemical and mineralogical characteristics of sediment samples from the northern South China Sea, aiming to investigate the enrichment mechanisms of trace elements into pyrites in methane seep systems. We applied laser ablation–inductively coupled plasma–mass spectrometry (LA-ICP-MS) to analyze the trace element patterns of pyrites in core Z22–3. We used Sr/Ca-Mg/Ca, (Mo/U) <jats:sub>EF</jats:sub> values, chromium reducible sulfur (CRS) content, total organic carbon (TOC), δ<jats:sup>34</jats:sup>S, and δ<jats:sup>13</jats:sup>C values of bulk sediments to determine the position of sulfate–methane transition zones (SMTZs). Progressively more positive δ<jats:sup>34</jats:sup>S values (up to −36.54‰) of the CRS and an increase in Mg/Ca indicate the enhancement of SD-AOM, suggesting that the position of SMTZs is located at depths of 181 to 481 and 1,101 to 1,401 cmbsf. Within SMTZs, pyrites exhibit obvious enrichments in Co, Ni, Mo, and Pb and depletion in Mn, Zn, Cu, and V. We discuss the process of methane seepage affecting trace elements in pyrites: the reductive dissolution of iron/manganese oxyhydroxide aggregates fueled by the enhancement of AOM and substitution for ferrous in pyrites contribute to the enrichments of Mo, Co and Ni in pyrites. Elements with faster water exchange kinetics rates than Fe, such as Cu, Pb and Zn, rather precipitate as independent metal sulfides than incorporating into pyrite, thus resulting in the depletion of these trace elements in pyrites. This study provides novel insight into the deep-sea trace element cycle between sediments and authigenic pyrites, establishing geochemical indicators of AOM based on trace element patterns in pyrites.","PeriodicalId":12479,"journal":{"name":"Frontiers in Marine Science","volume":"20 1","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-10-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145241242","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 primary controls of coral reef carbonate karstification in the South China Sea since the Miocene","authors":"Yang Yang, Kefu Yu, Bin Xiong, Wei Jiang, Shendong Xu, Rui Wang, Tianlai Fan","doi":"10.3389/fmars.2025.1619169","DOIUrl":"https://doi.org/10.3389/fmars.2025.1619169","url":null,"abstract":"Coral reef karstification plays a vital role in sea-air CO<jats:sub>2</jats:sub> exchange, yet its mechanisms remain unclear. This study employs an 878.22-m coral reef sequence (dating to19.6 Ma) from Well CK2 in the Xisha Islands, South China Sea (SCS), to investigate karstification processes, including their signatures, primary controls, and implications for marine carbonate dissolution in global carbon cycling. Petrological and geochemical analyses of CK2 revel distinct karstification characteristics, including: (1) higher surface porosity 25–30%), with randomly distributed pores and fractures of variable sizes and shapes; (2) yellowish-brown to black impregnations; (3) micritic cements accompanied by well-crystallized mineral crystals, and (4) moderately well-sorted and rounded grains. Geochemical signatures show elevated <jats:sup>8787</jats:sup>Sr/<jats:sup>86</jats:sup>Sr, Mn content, and Mn/Sr ratios, coupled with depleted δ¹³C, δ<jats:sup>18</jats:sup>O and Sr content. These features collectively indicate that karstification in CK2 was dominated by non-selective dissolution and recrystallization processes, principally occurring at the mixing zone in meteoric water systems during prolonged subaerial exposure. Karstification signatures varied across geological epochs, implying different controlling mechanisms. Late Miocene (12.6–10.2 Ma), driven by sustained sea-level fall, exhibited an extreme <jats:sup>87</jats:sup>Sr/<jats:sup>86</jats:sup>Sr shift and severe erosion. Pleistocene (2.2–1.8, 1.1–0.89, 0.29 and 0.2 Ma), influenced by frequent sea-level fluctuations and warm, humid environments linked to glacial-interglacial cycle and Asian monsoon, displayed the highest surface porosity (15–40%, mean 25%), ochre to tawny impregnations, and micritized cements, along with negative δ¹³C-δ<jats:sup>18</jats:sup>O and elevated <jats:sup>87</jats:sup>Sr/<jats:sup>86</jats:sup>Sr and Mn/Sr ratios. In contrast, the Middle Miocene Climatic Optimum (16.6–16 Ma) lacked typical karst characteristics but comprised of well-rounded and sorted coral gravels, suggesting reef-building organisms mediate karstification via substrate architecture. These findings demonstrate that sea-level changes and climate conditions control coral reef karstification intensity. Concurrently, dissolution during karstification may significantly modify ocean alkalinity and dissolved inorganic carbon, with potential feedback on carbon cycling in future climate scenarios.","PeriodicalId":12479,"journal":{"name":"Frontiers in Marine Science","volume":"19 1","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145234990","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":"Environmental conditions and carbonate chemistry variability influencing coral reef composition along the Pacific coast of Costa Rica","authors":"Celeste Sánchez-Noguera, Ines D. Lange, Jorge Cortés, Carlos Jiménez, Christian Wild, Tim Rixen","doi":"10.3389/fmars.2025.1606253","DOIUrl":"https://doi.org/10.3389/fmars.2025.1606253","url":null,"abstract":"Coral reef development is influenced by a wide variety of factors, including temperature, salinity, nutrient concentrations, and carbonate chemistry. Studies focusing on physicochemical drivers of coral reef distribution and composition in the Eastern Tropical Pacific (ETP) are scarce, and carbonate chemistry and nutrient data for this region are limited. This study measured coral reef composition and physicochemical parameters along the Pacific coast of Costa Rica, over a one-year period at three locations: Santa Elena and Matapalo in the north, and Parque Nacional Marino Ballena in the south. Our results show high seasonal and spatial variability of physicochemical conditions with significant differences mainly explained by inorganic nutrient concentrations, with driving processes also having a strong influence on the variability of carbonate chemistry parameters. Coastal upwelling is the main driver of the seasonal variability in Santa Elena. Comparison of seasonal dissimilarity within locations confirms the presence of a geographical gradient, with stronger influence of the upwelling in Santa Elena relative to Matapalo, where several parameters displayed a lower seasonality and a carbonate system that supports reef development throughout the year. Conversely, in Marino Ballena the river discharges during rainy season exerted a strong control on the seasonal variability. The integrated analysis of coral reef composition and physicochemical parameters suggests that in addition to inorganic nutrients carbonate chemistry also plays a key role in coral distribution. Analyzing the spatial distribution of the main reef builders provides insights into the species-specific tolerance to varying conditions. <jats:italic>Pavona clavus</jats:italic> is widely distributed in both the northern and southern locations, suggesting that this massive coral is very tolerant to the high variability of physicochemical conditions. The dominant corals in the north (<jats:italic>Pavona gigantea</jats:italic> and <jats:italic>Pocillopora</jats:italic> spp.) are highly tolerant to nutrient-enriched cold waters with low aragonite saturation, while one of the main reef-builders in southern locations (<jats:italic>Porites</jats:italic> cf. <jats:italic>lobata</jats:italic>) cope better with low salinity, low aragonite saturation and low light intensity caused by river discharges. Understanding the preferences of individual coral species at our study locations can shed light on the environmental factors driving coral reef distribution in other locations of the ETP.","PeriodicalId":12479,"journal":{"name":"Frontiers in Marine Science","volume":"108 1","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145234996","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":"Hydrodynamic alterations induced by floating solar structures co-located with an offshore wind farm","authors":"Pauline Denis, Arthur Capet, Jan Vanaverbeke, Thomas R. H. Kerkhove, Geneviève Lacroix, Sébastien Legrand","doi":"10.3389/fmars.2025.1674859","DOIUrl":"https://doi.org/10.3389/fmars.2025.1674859","url":null,"abstract":"Floating photovoltaic installations (FPV) are among the promising emerging marine renewable energy systems contributing to future global energy transition strategies. FPVs can be integrated within existing offshore wind farms, contributing to more efficient use of marine space. This complementarity has gained increasing attention as a sustainable approach to enhance green energy production while reducing offshore grid infrastructure costs, particularly in the North Sea. This study presents a first assessment to quantify the mid- and far-field hydrodynamic effects of FPVs (elevated design) deployed within an existing offshore wind farm (OWF) in the Belgian part of the North Sea. A subgrid-scale parameterization was adopted into the 3D hydrodynamic model COHERENS to assess impacts on four key hydrodynamic metrics: surface irradiance reduction due to shading, changes in current velocity fields, turbulent kinetic energy production, and variations in current-induced bottom shear stress. Four scenarios were compared: a baseline without structures, a scenario with only offshore wind turbines and two combined wind and photovoltaic configurations (sparse and dense). At farm scale, simulations showed small effects of FPV shading on sea surface temperature (&amp;lt; 0.1°C), but significant reductions in current speed, increased turbulent kinetic energy mainly beneath the floaters, and a noticeable impact on bottom shear stress. This hydrodynamic modeling study constitutes a first step toward a comprehensive environmental impact assessment of FPVs, particularly in relation to their biogeochemical effects on the water column and benthic habitats. The findings provide valuable insights to support sustainable marine spatial planning, environmental assessments, and industrial design strategies in the North Sea and beyond.","PeriodicalId":12479,"journal":{"name":"Frontiers in Marine Science","volume":"20 1","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145235054","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":"Myth and reality on human rights at sea in the era of globalization","authors":"Zhipeng Cui, Xingguo Cao, Pengfei Zhang","doi":"10.3389/fmars.2025.1657709","DOIUrl":"https://doi.org/10.3389/fmars.2025.1657709","url":null,"abstract":"The twenty-first-century maritime sector, shaped by globalization, technological advances, and economic shifts, faces persistent gaps in safeguarding seafarers’ rights. Despite international efforts like the ILO’s Maritime Labor Convention 2006, their effectiveness is undermined by the industry’s polycentric governance, weak compliance mechanisms, and the isolated nature of seafaring profession. Through a review of regulatory gaps and case studies, it demonstrates how current standards fall short in practice, arguing that their decentralized structure and weak implementation fail to address systemic risks. This study proposes supplementary measures to strengthen accountability and compliance, emphasizing the need for coordinated action to protect seafarers in an increasingly deregulated industry.","PeriodicalId":12479,"journal":{"name":"Frontiers in Marine Science","volume":"9 1","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145234992","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":"Within-reef biomass partitioning in a Mediterranean vermetid reef: a baseline for future monitoring","authors":"Francesco Paolo Mancuso, Luca Bisanti, Flavio Picone, Renato Chemello","doi":"10.3389/fmars.2025.1656826","DOIUrl":"https://doi.org/10.3389/fmars.2025.1656826","url":null,"abstract":"Biomass is an essential indicator for assessing the quality, stability, productivity, and health of ecosystems and it is increasingly used as a practical monitoring parameter within the Essential Ocean Variables (EOV) framework. In the Mediterranean Sea, vermetid reefs - unique bioconstructions structurally comparable to fringing coral reefs - play a significant role in coastal dynamics yet remain understudied. This study aimed to quantify the biomass distribution of the main structural species <jats:italic>Dendropoma cristatum</jats:italic>, seaweeds, and associated fauna found across three distinct reef zones: the inner edge (adjacent to the mainland with limited water movement), the cuvette (a central zone characterized by shallow, sheltered pools), and the outer edge (directly exposed to constant wave action). Rather than testing for a causal “zone effect”, we provide a site-specific quantitative baseline that can be used to track future change and to generate hypotheses on the environmental drivers of biomass patterns. Samples were collected from a vermetid reef in north-western Sicily, Italy, and biomass was estimated as ash-free dry weight (AFDW; a measure of organic matter excluding mineral content). This exploratory study of spatial patterns within one reef site revealed an average biomass of 321.4 g AFDW m<jats:sup>−2</jats:sup>, with values that increased from the inner edge to the outer zone within the single site studied. <jats:italic>D. cristatum</jats:italic> biomass was highest at the outer edge (likely reflecting its preference for stronger water movement and higher food supply), while seaweed biomass peaked in the outer edge and cuvette, where macroalgal diversity was greatest. Phytal fauna biomass was strongly correlated with seaweed biomass (R² = 0.68), emphasizing the role of macroalgae as ecosystem engineers, whereas vagile fauna were more abundant in the inner edge and cuvette, possibly benefiting from increased structural complexity and reduced predation. These site-specific findings illuminate spatial patterns of biomass distribution within this vermetid reef and provide essential baseline data for monitoring this location, whilst generating hypotheses for testing at other Mediterranean vermetid reef sites.","PeriodicalId":12479,"journal":{"name":"Frontiers in Marine Science","volume":"50 1","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-10-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145235052","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":"Can international investment agreements protect investments in non-territorial waters?—institutional foundations, jurisdictional analysis, and pathways for improvement","authors":"Xingyi Duan, Ziheng Liu","doi":"10.3389/fmars.2025.1654756","DOIUrl":"https://doi.org/10.3389/fmars.2025.1654756","url":null,"abstract":"The adoption of the United Nations Convention on the Law of the Sea (UNCLOS) and subsequent developments in State practice have prompted a growing number of International Investment Agreements (IIAs) to include \"definition of territory clauses,\" extending their legal applicability beyond territorial waters. Yet the fragmented nature of the IIA regime has resulted in significant variations in the formulation and substantive scope of these provisions across different treaties. Concurrently, persistent divergences persist among States regarding the interpretation of sovereign rights and jurisdiction exercisable in various maritime zones—including the exclusive economic zone, the continental shelf, the high seas, and the international seabed area—which fundamentally shapes the applicability of IIAs to investments in non-territorial marine spaces. Determining such applicability carries broader implications for the interpretation and implementation of UNCLOS, particularly concerning marine environmental protection obligations and dispute settlement mechanisms. The complexity of this legal interplay underscores the need for rigorous scholarly analysis and coordinated policy responses. The international community should take proactive steps toward prescriptive and practical reforms to clarify the application of IIAs to investments in non-territorial waters. When properly defined and implemented, extending IIA protections to maritime investments could not only promote sustainable blue economic activities but also strengthen the international rule of law in ocean governance.","PeriodicalId":12479,"journal":{"name":"Frontiers in Marine Science","volume":"121 1","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145209954","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":"Analysis of the gut-specific microbiome from critically endangered hawksbill sea turtles (Eretmochelys imbricata) using a culture-dependent approach","authors":"Hongwei Li, Yuan Chen, Zhongrong Xia, Yunyong Lin, Ruijun Xu","doi":"10.3389/fmars.2025.1671894","DOIUrl":"https://doi.org/10.3389/fmars.2025.1671894","url":null,"abstract":"IntroductionThe critically endangered hawksbill turtle (Eretmochelys imbricata) is essential for healthy coral reef ecosystems, and its gut microbiota plays a vital role in host nutrition and overall health. A comprehensive understanding of this microbial diversity is crucial for effective conservation, yet current knowledge remains limited. This study aimed to characterize the bacterial taxa present in the fecal samples of hawksbill turtles using culture-dependent methods.MethodsFecal samples from hawksbill turtles were cultured under both aerobic and anaerobic conditions using two distinct bacterial media. A total of 161 bacterial strains were isolated and identified using standard microbiological techniques and 16S rRNA gene sequencing.ResultsThe isolated strains were classified into three phyla: Pseudomonadota (formerly Proteobacteria), Actinomycetota, and Bacillota (formerly Firmicutes). The most frequently identified species were <jats:italic>Psychrobacter celer, Shewanella algae, Sulfitobacter pontiacus, Vibrio mytili, Enterococcus hirae</jats:italic>, and <jats:italic>Psychrobacter maritimus</jats:italic>. Ten isolates were identified as potentially representing six novel bacterial species.DiscussionThis study expands our understanding of the microbial diversity associated with hawksbill turtles. It demonstrates the utility of fast and simple culture-dependent approaches for characterizing the microbiota of endangered species, providing a foundation for future research into the roles of these bacteria in turtle health and reef ecosystem function.","PeriodicalId":12479,"journal":{"name":"Frontiers in Marine Science","volume":"116 1","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145210014","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":"Identify habitat distribution within the mesoscale eddies for jumbo flying squid off Chilean waters","authors":"Xiaoci Wu, Pengchao Jin, Wei Yu","doi":"10.3389/fmars.2025.1669638","DOIUrl":"https://doi.org/10.3389/fmars.2025.1669638","url":null,"abstract":"Mesoscale eddies exert profound influences on marine environments, thereby regulating habitat quality and the distribution of marine organisms. The waters off Chile are a region of intense mesoscale eddy activity and represent a major habitat for the jumbo flying squid (<jats:italic>Dosidicus gigas</jats:italic>), a short-lived and economically important species. However, the effects of mesoscale eddies on the habitat of <jats:italic>D. gigas</jats:italic> in this region remain poorly understood. In this study, we integrated autumn (March-May) fisheries data of <jats:italic>D. gigas</jats:italic> from 2015 to 2021 with environmental variables, including sea surface temperature (SST), chlorophyll-a concentration (Chl-a), and sea surface dissolved oxygen concentration (DO), to develop and validate habitat suitability index (HSI) models with different weighting schemes. Using the optimal HSI model in combination with mesoscale eddy data, we compared the impacts of cyclonic and anticyclonic eddies on <jats:italic>D. gigas</jats:italic> abundance and habitat suitability. The results revealed that the optimal HSI model effectively predicted the potential habitats of <jats:italic>D. gigas</jats:italic>, with weights for SI<jats:sub>DO</jats:sub>, SI<jats:sub>SST</jats:sub>, and SI<jats:sub>Chl-a</jats:sub> of 0.1, 0.1, and 0.8, respectively. Compared with anticyclonic eddies, cyclonic eddies provided broader areas of suitable habitats, characterized by suitable Chl-a and DO levels, and supported higher <jats:italic>D. gigas</jats:italic> abundances. Furthermore, the habitat suitability of <jats:italic>D. gigas</jats:italic> within mesoscale eddies exhibited interannual variability and was significantly correlated with the radius, velocity, and amplitude of the eddies. This study highlighted the critical role of mesoscale eddies in shaping the habitat suitability of <jats:italic>D. gigas</jats:italic> and provided valuable insights for the management and conservation of cephalopod resources.","PeriodicalId":12479,"journal":{"name":"Frontiers in Marine Science","volume":"41 1","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145210019","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":"Posidonia oceanica banquette accumulations in southern Catalonia: management approaches and key parameters for coastal protection","authors":"Carlos Astudillo-Gutierrez, Eva Pavo-Fernandez, Vicente Gracia, Joan Pau Sierra, Toni Llull, Cesar Mosso, Xavier Sanchez-Artus, Agustín Sanchez-Arcilla","doi":"10.3389/fmars.2025.1681826","DOIUrl":"https://doi.org/10.3389/fmars.2025.1681826","url":null,"abstract":"Seagrass banquettes, formed primarily by <jats:italic>Posidonia oceanica</jats:italic>, play a critical role in coastal protection and sediment dynamics. However, due to their perceived negative impact on seaside tourism, local authorities frequently remove these accumulations using heavy machinery, contributing to beach erosion. This study surveyed a 100 km stretch of the southern Catalan coastline to map the spatial distribution of <jats:italic>Posidonia oceanica</jats:italic> banquettes and to investigate their relationship with adjacent submerged seagrass meadows. The results indicate that banquette development is most prevalent in meadows with a depth of less than 5 m, under local wave conditions with significant wave heights ranging from 0.4 to 0.8 m. Pixavaques Beach was selected as a case study to evaluate the physical characteristics and ecological functions of banquettes. Granulometric and permeability analyses were conducted on sand and banquette samples, alongside <jats:italic>in situ</jats:italic> penetration resistance measurements. The results indicate that banquettes located near the shoreline accumulate around 12 times less sediment than those located further inland, primarily due to their continuous exposure to wave action, which produces a natural washing and removal of sediments. The mean permeability values of the banquette were 16.41 <jats:italic>cms</jats:italic><jats:sup>− 1</jats:sup> in the zones closest to the shoreline and 0.32 <jats:italic>cms</jats:italic><jats:sup>− 1</jats:sup> at a distance of 1.5 m inland. The values obtained for these samples were higher than those measured in bare sand (0.05 <jats:italic>cms</jats:italic><jats:sup>− 1</jats:sup>). The maximum <jats:italic>in situ</jats:italic> penetration resistance values were recorded as 1.84 MPa in bare sand and 1.68 MPa in the banquettes. The highest values measured within the banquettes indicate zones of greater sediment accumulation. Additionally, the artificial nourishment implemented to counteract erosion from banquette removal has led to increased grain size and steeper beach profiles. These findings highlight the protective function of banquettes and support alternative, sustainable management strategies, such as repositioning or partial retention, that balance ecological integrity with the demands of coastal tourism.","PeriodicalId":12479,"journal":{"name":"Frontiers in Marine Science","volume":"28 1","pages":""},"PeriodicalIF":3.7,"publicationDate":"2025-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145209955","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}