Regional Studies in Marine Science最新文献

{"title":"Mercury contamination in imported shark meat (“cação”) and implications for human exposure in Brazil","authors":"Lucas Cabrera Monteiro,&nbsp;Fábio José Viana Costa,&nbsp;Carlos Benigno Vieira de Carvalho,&nbsp;Adhim Santiago Júnior,&nbsp;Bruno Altoé Duar,&nbsp;José Vicente Elias Bernardi","doi":"10.1016/j.rsma.2026.105214","DOIUrl":"10.1016/j.rsma.2026.105214","url":null,"abstract":"<div><div>Brazil is the largest global consumer of shark meat, marketed as “cação,” yet traceability and risk assessment are limited due to unclear labeling and insufficient monitoring. Shark meat is a source of toxic elements, particularly mercury (Hg), posing significant health risks, especially for children and vulnerable populations. Total Hg (THg) was quantified in dorsal muscle samples obtained from carcasses of animals marketed in Brazil as “cação”. Based on DNA barcoding, <em>Prionace glauca</em> (blue shark) was identified in 38 samples and <em>Makaira nigricans</em> (blue marlin) in one sample. Total Hg concentrations ranged from 0.336 to 2.758 mg kg⁻¹ wet weight (mean: 1.363 ± 0.559 mg kg⁻¹), with 95% and 77% of samples exceeding international and national safety limits, respectively. Estimated weekly Hg intake for children (6–13 years) ranged from 0.805 to 6.613 µg kg⁻¹, with 91% above the provisional tolerable weekly intake (PTWI). For adults, weekly intake ranged from 0.525 to 4.315 µg kg⁻¹, with 71% exceeding the PTWI. Based on the 90th percentile of maximum safe consumption quantity values, a weekly intake of approximately 40 g of imported shark meat was recommended for children and 75 g for adults. However, the consumption of shark meat should be avoided whenever possible. Significant public health risks were associated with imported shark meat sold as “cação” due to elevated Hg concentrations and the frequent mislabeling of threatened species. Stricter inspection protocols, improved traceability systems, and broader monitoring efforts are needed to reduce Hg exposure and improve species identification in shark products.</div></div>","PeriodicalId":21070,"journal":{"name":"Regional Studies in Marine Science","volume":"100 ","pages":"Article 105214"},"PeriodicalIF":2.7,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148570593","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Integrating oceanographic and human-related drivers to explain spatial and temporal patterns of bottlenose dolphin strandings over the last three decades in the Mexican Caribbean","authors":"Catalina Ocampo-Carvajal,&nbsp;Janneth Adriana Padilla-Saldívar,&nbsp;Salvador Ernesto Julio-Cardoso,&nbsp;Sarah Martinez,&nbsp;Nataly Castelblanco-Martínez","doi":"10.1016/j.rsma.2026.105189","DOIUrl":"10.1016/j.rsma.2026.105189","url":null,"abstract":"<div><div>Marine mammal strandings provide valuable insights into ecosystem health, species ecology, and anthropogenic pressures in coastal ecosystems. To understand what factors are influencing the spatial distribution of stranding events, we integrated long-term stranding data (1993–2024) of bottlenose dolphins (<em>Tursiops truncatus</em>) along the Quintana Roo coast, Mexican Caribbean, with biological characteristics, spatial patterns, oceanographic forcing, and human accessibility. To assess mortality patterns, we modeled onshore stranding probability using wind dynamics, surface currents, and anthropogenic accessibility. Generalized Additive Models identify persistent easterly and southeasterly winds as the dominant drivers of carcass transport, while current direction exerted a weaker influence. Stranded dolphins (51) were analyzed, with cases peaking in Rainy/Hurricane Season (June–November). The spatial distribution was uneven, showing hotspots at the South Zone and North Zone 1, with the South Zone concentrating more than 75% of the events. Sample recovery and necropsies were conducted in 41.2% of cases, and causes of death were determined in 25%, highlighting logistical and institutional limitations. The probability of detecting strandings onshore was influenced by accessibility, revealing a detection bias linked to coastal access and human population density. The final model explained 95.7% of deviance and showed high predictive performance (AUC = 0.9989). Results indicate stranding hotspots emerging from interaction between wind-driven drift processes and human detection capacity, rather than localized mortality isolated. Incorporating oceanographic and anthropogenic layers into stranding analyses is essential for improving ecological inference, correcting reporting biases, and strengthening evidence-based coastal management and marine mammal conservation strategies in rapidly developing regions.</div></div>","PeriodicalId":21070,"journal":{"name":"Regional Studies in Marine Science","volume":"100 ","pages":"Article 105189"},"PeriodicalIF":2.7,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148570683","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Fishing practices and local ecological knowledge in artisanal fisheries: Implications for elasmobranch conservation in northeastern Brazil","authors":"Alan Victor Andrade Canton ,&nbsp;Derick Lira ,&nbsp;Maria Lacerda ,&nbsp;Heitor Oliveira Braga ,&nbsp;Cristiano Queiroz de Albuquerque","doi":"10.1016/j.rsma.2026.105180","DOIUrl":"10.1016/j.rsma.2026.105180","url":null,"abstract":"<div><div>Small-scale fisheries operate at the intersection of food security, livelihoods, and biodiversity conservation, yet they remain among the least monitored marine systems. This study applies an integrated socio-ecological framework to examine how fishing practices, socioeconomic vulnerability, and experiential knowledge interact to shape pressure on sharks and rays along the northern coast of Rio Grande do Norte, Brazil. Semi-structured interviews were conducted with artisanal fishers across five fishing colonies, generating data on socioeconomic conditions, fishing practices, catch composition, seasonal patterns, and population perceptions. Quantitative analyses combined descriptive statistics and regression models to evaluate drivers of ecological knowledge, perceptions of decline, and species citation probability. The results reveal a vulnerable fishing sector characterized by advanced age, low educational attainment and strong economic dependence on fishing. Despite the artisanal profile of the fleet, substantial catch volumes and the widespread use of non-selective gear, sustained pressure on multiple elasmobranch taxa, including threatened species. Perceptions of declining abundance and reduced body size of elasmobranchs were nearly universal and independent of age, experience, or education. However, awareness of formal conservation status was low, revealing a gap between local observations and institutional conservation frameworks. Importantly, peak fishing activity overlapped with reported reproductive periods, suggesting heightened risks to population recovery. By integrating socioeconomic vulnerability, fishing dynamics, and local knowledge, this study provides policy-relevant evidence for data-poor fisheries. The findings highlight the need for participatory management strategies that reconcile conservation objectives with livelihood security and strengthen the implementation of Brazilian ocean policies.</div></div>","PeriodicalId":21070,"journal":{"name":"Regional Studies in Marine Science","volume":"100 ","pages":"Article 105180"},"PeriodicalIF":2.7,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148380097","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Driving mechanisms of functional groups in soil particulate organic matter in different Suaeda salsa habitats of the Yellow River Delta","authors":"Can Lu,&nbsp;Leping Zhang,&nbsp;Chong You,&nbsp;Yan Zhang,&nbsp;Hailong Wu,&nbsp;Fude Liu","doi":"10.1016/j.rsma.2026.105178","DOIUrl":"10.1016/j.rsma.2026.105178","url":null,"abstract":"<div><div>Plant stoichiometry significantly influences the accumulation and stability of soil particulate organic matter (POM). This study analyzed soil profiles (0–30 cm depth) of <em>Suaeda salsa</em> communities in the intertidal habitat (Habitat I) and supratidal habitat (Habitat II) of the Yellow River Delta. Fourier transform infrared spectroscopy (FT-IR) combined with two-dimensional correlation spectroscopy (2D-COS) was employed to characterize POM functional group structures and identify their dynamic response characteristics under habitat perturbation. Plant C:N:P stoichiometry and soil physicochemical factors were integrated to elucidate the driving mechanisms of POM. Key findings include: (1) POM functional group composition differed significantly between habitats but showed minimal variation with soil depth. POM in Habitat I was dominated by hydrophilic groups, while POM in Habitat II was characterized by hydrophobic groups. (2) The 2D-COS analysis revealed that polysaccharide-associated C–O groups exhibited earlier spectral responses to habitat perturbation than aromatic C<img>C and N–H groups, indicating higher environmental sensitivity of hydrophilic components. The response intensity of functional groups gradually weakened with increasing soil depth, suggesting enhanced microstructural stability of deeper POM fractions. (3) Plant stoichiometry significantly influenced POM functional group composition. In Habitat II, higher foliar C and a lower leaf C:N promoted the enrichment of aromatic functional groups, contributing to relatively greater chemical recalcitrance of POM. Environmental factors also critically affected POM composition. Higher salinity and periodic tidal inundation in Habitat I favored POM accumulation despite the predominance of hydrophilic functional groups. This study reveals that stoichiometric regulation by plants modulates the composition mechanisms of POM functional groups across habitats, offering critical insights for wetland carbon cycling and carbon sequestration.</div></div>","PeriodicalId":21070,"journal":{"name":"Regional Studies in Marine Science","volume":"100 ","pages":"Article 105178"},"PeriodicalIF":2.7,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148570574","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Distance-dependent variation in the tintinnid ciliate assemblage around a tropical oceanic archipelago","authors":"Alejandro Esteweson Santos Faustino da Costa,&nbsp;Sigrid Neumann-Leitão,&nbsp;Pedro Augusto Mendes de Castro Melo,&nbsp;Jana Ribeiro de Santana","doi":"10.1016/j.rsma.2026.105220","DOIUrl":"10.1016/j.rsma.2026.105220","url":null,"abstract":"<div><div>Tropical oceans are characterized by a strong thermocline that limits nutrient enrichment of surface waters, yet elevated biological productivity near oceanic islands is well documented. Given the ecological importance of tintinnid ciliates in the microbial loop, we investigated how their assemblage structure responds to a potential island‑mass effect around the Saint Peter and Saint Paul Archipelago (SPSPA) under contrasting rainfall regimes. Samples were collected at 24 sites located near and far from the archipelago during periods of maximum and minimum rainfall, using a 10 L Niskin bottle at seven depths. Tintinnid spatial distribution was influenced by distance from the SPSPA and by rainfall regime (ANOVA, p &lt; 0.001). Densities were higher in distant areas and during maximal rainfall, while lower densities near the archipelago may reflect competition with polycystine radiolarians, which increase in abundance closer to the islands. Species richness also differed between zones (permutation test, p &lt; 0.001), increasing with distance from the SPSPA. We recorded 46 tintinnid species overall; all occurred in distant areas, whereas only 19 were found near the archipelago. Assemblage structure varied with distance and rainfall, and shifts in dominant species in distant areas suggest changes in mineral particle availability for lorica construction.</div></div>","PeriodicalId":21070,"journal":{"name":"Regional Studies in Marine Science","volume":"100 ","pages":"Article 105220"},"PeriodicalIF":2.7,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148570580","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Vulnerable European spiny lobster Palinurus elephas (Fabricius, 1787): A body-size based and fishery study from NW Aegean Sea, Greece","authors":"Thodoros E. Kampouris,&nbsp;Dimitris Klaoudatos,&nbsp;Michaela Doukari,&nbsp;Drosos Koutsoubas,&nbsp;Ioannis E. Batjakas","doi":"10.1016/j.rsma.2026.105221","DOIUrl":"10.1016/j.rsma.2026.105221","url":null,"abstract":"<div><div>The European spiny lobster, <em>Palinurus elephas</em> (spiny lobster or <em>P.elephas</em> thereafter), a highly valued species in the NW Aegean Sea, Greece, faces significant fishery pressure and population decline. This study provides novel insights into its biology, population dynamics, and fishery status in Thermaikos Gulf and the National Marine Park of Alonissos and Northern Sporades (NMPANS). Using data from 308 individuals collected in 2018–2019, we assessed morphometric relationships, age composition, growth, mortality, and exploitation rates. Carapace length-weight relationships showed negative allometry, with no significant sex differences. Eight age classes were identified, with a dominant fourth-year cohort (43.35%). Von Bertalanffy growth models estimated an asymptotic length of 234.09 mm and longevity of 24.6 years. The exploitation rate (0.85) exceeds sustainable limits (EMSY = 0.55), indicating overfishing, with fishing mortality (0.85) surpassing FMSY (0.17). Larger individuals were found in NMPANS, suggesting some protective effect, but the population remains at risk of collapse. Greek fish auction data revealed potential illegal landings, highlighting enforcement challenges. We recommend reduced landings, enhanced gear selectivity, and systematic monitoring to ensure sustainability. These findings underscore the need for ecosystem-based management to conserve <em>P. elephas</em> and associated threatened species.</div></div>","PeriodicalId":21070,"journal":{"name":"Regional Studies in Marine Science","volume":"100 ","pages":"Article 105221"},"PeriodicalIF":2.7,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148570581","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Geographical and seasonal variations of copepod communities from Ise-Mikawa Bay to open-ocean waters affected by the warm Kuroshio Current","authors":"Sayaka Sogawa,&nbsp;Kazuaki Tadokoro,&nbsp;Kazuhiro Aoki,&nbsp;Rentaro Nakashima","doi":"10.1016/j.rsma.2026.105158","DOIUrl":"10.1016/j.rsma.2026.105158","url":null,"abstract":"<div><div>Copepods play a crucial role in coastal ecosystems and support fisheries production. This study revealed distinct spatial and seasonal variations in copepod communities in and around semi-enclosed Ise-Mikawa Bay, Japan. A warm-water community (Group I) dominated the outer bay throughout the year, whereas the dominant communities in the inner bay underwent strong seasonal transitions. From winter to early spring, a cold-water-period community (Group IIA) prevailed. Group IIA was followed by a spring shelf-slope water community (Group IIB). In summer, a mixed community of cold- and warm-water species (Group IIC) appeared. The variations of the duration of dominance by these inner-bay communities between Ise Bay and Mikawa Bay reflected the stronger estuarine characteristics of Mikawa Bay. In autumn, copepod communities in the inner bay shifted to warm-water communities (Group I); an inner-bay community (IC) prevailed in September, and a coastal-to-open-ocean community (IB) prevailed in November. These spatiotemporal shifts were shaped by intrusion of open-ocean water, freshwater input, and seasonal changes of environmental factors such as temperature, salinity, and dissolved oxygen concentrations, particularly in the bay. The distribution of the genus <em>Acartia</em>, which frequently dominates in shallow, estuarine environments and has evolved a life cycle involving temperature-cued resting eggs, responded to species-specific, fine-scale conditions and provided a valuable indicator of seasonal and spatial environmental changes, freshwater discharge, open-ocean water exchange, and potential climate change impacts in the bay. This study highlighted complex hydrographic-biological interactions, the sensitivity of planktonic communities to physical and chemical environmental changes, and the spatial heterogeneity in semi-enclosed coastal ecosystems.</div></div>","PeriodicalId":21070,"journal":{"name":"Regional Studies in Marine Science","volume":"100 ","pages":"Article 105158"},"PeriodicalIF":2.7,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148570661","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Temporal variation in the pigment content of four macroalgae species: Implications for biotechnological applications","authors":"Marina Salido,&nbsp;Jone Bilbao,&nbsp;Manu Soto,&nbsp;Sergio Seoane","doi":"10.1016/j.rsma.2026.105201","DOIUrl":"10.1016/j.rsma.2026.105201","url":null,"abstract":"<div><div>Pigments exhibit a wide range of biological activities, including anti-inflammatory, antioxidant, anticancer, and anti-obesity effects, with potential applications in the food industry and human health. However, pigment profiles on algae depend on many factors, such as geographical location, season, species, and quantification method. This study aimed to evaluate the temporal variation in pigment yield among four local macroalgae species (<em>Ulva rigida</em>, <em>Bifurcaria bifurcata</em>, <em>Halopteris scoparia</em>, and <em>Halopithys incurva)</em> to identify their potential for biotechnological applications. Moreover, the effect of freeze–thaw extraction pretreatment was assessed. These species were collected by hand from spring to autumn 2023 in the Southeastern Bay of Biscay. Pigment analysis was carried out using high-performance liquid chromatography for lipophilic pigments and spectrophotometry for hydrophilic pigments. Temporal variation was observed among algae pigments, without consistent trends between groups of pigments or species, except for β-carotene, which reached a maximum in late spring, suggesting its photoprotective characteristic. This study provides useful information for achieving an optimal pigment content in four algae species, offering interesting insights into methodologies for quantifying pigments, which could have direct implications and applications in the biotechnological and food industries.</div></div>","PeriodicalId":21070,"journal":{"name":"Regional Studies in Marine Science","volume":"100 ","pages":"Article 105201"},"PeriodicalIF":2.7,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148570679","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reef fish diversity and community composition revealed using BRUV surveys in the remote damer marine protected area","authors":"Andrianus Sembiring,&nbsp;Ambariyanto Ambariyanto,&nbsp;Subagiyo Subagiyo,&nbsp;Rita Rachmawati,&nbsp;Retno Hartati,&nbsp;Ni Putu Dian Pertiwi,&nbsp;Ni Luh Astria Yusmalinda,&nbsp;Luh Putu Candra Apriliani,&nbsp;Ni Komang Rossa Sri Savitri,&nbsp;Muhammad Danie Al Malik,&nbsp;Mochamad Iqbal Herwata Putra,&nbsp;Mark Erdmann,&nbsp;Alan White","doi":"10.1016/j.rsma.2026.105187","DOIUrl":"10.1016/j.rsma.2026.105187","url":null,"abstract":"<div><div>The Indonesian government has established an extensive network of Marine Protected Areas (MPAs) as one of key strategies to conserve biodiversity. Yet many of these areas remain weakly monitored, often because of limited human capacity, facilities and the challenges of managing remote locations. This is particularly evident at Damer Island, a newly established MPA where biodiversity data are still scarce. This study provides a first preliminary ecological baseline of reef fish assemblages based on Baited Remote Underwater Video (BRUV) surveys in Damer Island MPA, Southwest Maluku. A total of 22 BRUV deployments (22.98 h of video) were analyzed across core (no-take) and utilization (limited-use) zones, identifying 147 species of fish from 36 families, dominated by Balistidae, Pomacentridae, and Caesionidae. Apex predators were recorded, including four reef shark species (<em>Carcharhinus melanopterus</em>, <em>C. obscurus</em>, <em>C. amblyrhynchos</em>, <em>Triaenodon obesus</em>), though only eight individuals were observed, indicating extremely low shark abundance. Trophic group composition was dominated by carnivorous and omnivorous fishes, while herbivorous fishes represented a relatively small proportion of total abundance. Several commercially important taxa (<em>Lutjanus</em>, <em>Lethrinus</em>, <em>Siganus</em>) and the endangered Napoleon wrasse (<em>Cheilinus undulatus</em>) were also detected, highlighting the ecological and socioeconomic importance of the area. No significant differences in species richness, community composition, or trophic group composition were detected between Core and Utilization zones, suggesting that ecological differentiation associated with zoning may not yet be fully developed. Overall, this study establishes an important ecological baseline for future monitoring of the Damer Island MPA.</div></div>","PeriodicalId":21070,"journal":{"name":"Regional Studies in Marine Science","volume":"100 ","pages":"Article 105187"},"PeriodicalIF":2.7,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148570742","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Nutrient status, blue carbon stocks, and community perceptions in the seagrass meadows of Puttalam Lagoon, Sri Lanka: A socio-ecological assessment under monsoonal forcing","authors":"S.Y.S. Samarage,&nbsp;Hasitha Siriwardana,&nbsp;R.S.M. Samarasekara,&nbsp;M.L.A.M.S. Munasinghe,&nbsp;I.U. Kariyawasam","doi":"10.1016/j.rsma.2026.105154","DOIUrl":"10.1016/j.rsma.2026.105154","url":null,"abstract":"<div><div>Seagrass meadows are critical coastal ecosystems that provide nursery habitats, regulate nutrients, and sequester organic carbon. Despite their importance, tropical lagoons in Sri Lanka remain poorly studied. This study assessed seagrass diversity, seasonal nutrient dynamics, sediment organic carbon stocks, and community perceptions in the Puttalam Lagoon. Field surveys were conducted across four sampling campaigns representing the Northeast and Southwest monsoons between 2023 and 2025. Seagrass sampling was obtained by placing quadrats with three replicates; macronutrient analyses included total dissolved phosphorus, dissolved inorganic phosphorus, total dissolved nitrogen, and dissolved inorganic nitrogen; both vegetated (27) and non-vegetated (3) samples were extracted, using 0.6 m soil core; and thirty local stakeholders were interviewed. Five seagrass species were identified, with <em>Enhalus acoroides</em> dominant. Species densities were higher in the Northeast monsoon (mean 65.3 plants m⁻²) than in the Southwest (43.8 plants m⁻²). Seawater nutrients showed a phosphorus-dominated regime (N:P ratios &lt; Redfield), as a result of agricultural runoff and aquaculture inputs. One-way ANOVA test confirmed no statistically significant differences (P &gt; 0.05) in sediment carbon stocks in three sampling stations, the highest at the lagoon mouth (204.4 ± 44.4 Mg C ha⁻¹) and lowest at Dutch Bay (32.5 ± 16.3 Mg C ha⁻¹). Community surveys revealed moderate awareness of seagrass benefits for fisheries but limited recognition of carbon storage role. Findings highlight the ecological and socioecological importance of Puttalam Lagoon’s seagrass meadows. Protecting these habitats requires integrated monitoring of carbon and nutrient dynamics together with community-based conservation strategies to enhance resilience and blue-carbon benefits.</div></div>","PeriodicalId":21070,"journal":{"name":"Regional Studies in Marine Science","volume":"100 ","pages":"Article 105154"},"PeriodicalIF":2.7,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148570790","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"环境科学与生态学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}