Suzanne SH. Poiesz , Johannes IJ. Witte , Judith DL. van Bleijswijk , Harry J. Witte , Evaline M. van Weerlee , Maartje Brouwer , Sanne Vreugdenhil , Henk W. van der Veer , Lise Klunder
{"title":"Spatial variability of the coastal Wadden Sea fish community as revealed by environmental DNA","authors":"Suzanne SH. Poiesz , Johannes IJ. Witte , Judith DL. van Bleijswijk , Harry J. Witte , Evaline M. van Weerlee , Maartje Brouwer , Sanne Vreugdenhil , Henk W. van der Veer , Lise Klunder","doi":"10.1016/j.ecss.2025.109411","DOIUrl":"10.1016/j.ecss.2025.109411","url":null,"abstract":"<div><div>Previous studies have suggested the occurrence of spatial variability in the fish food web structure in the temperate Wadden Sea. However, these studies were carried out in different years and with different fishing devices. To eliminate interannual variability in fish abundance and the impact of sampling design, an environmental DNA (eDNA) study was performed monthly at eight locations over the spatial scale of the Dutch Wadden See year-round in 2018–2019. In total, 40 different individual fish species and 8 fish groups were identified. The number of fish species identified in the samples varied over time and among locations between three and 19 different fish species. Over the year, 20 species were identified at all locations; eight species were found at 6–7 locations and the remaining 30 species were found only incidentally. The spatial variability found in the Wadden Sea fish community is the result of the variability in presence of rare (transient) species, due to location specific differences in hydrographical and geomorphological characteristics.</div></div>","PeriodicalId":50497,"journal":{"name":"Estuarine Coastal and Shelf Science","volume":"323 ","pages":"Article 109411"},"PeriodicalIF":2.6,"publicationDate":"2025-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144491579","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Zy D. Perpetua , Frank Paolo Jay B. Albarico , Rey Y. Capangpangan , Ruei-Feng Shiu , Yee Cheng Lim , Chiu-Wen Chen , Cheng-Di Dong , Hernando P. Bacosa
{"title":"Meso- and microplastics accumulation and ecological risks in Philippine urban and rural sandy beaches","authors":"Zy D. Perpetua , Frank Paolo Jay B. Albarico , Rey Y. Capangpangan , Ruei-Feng Shiu , Yee Cheng Lim , Chiu-Wen Chen , Cheng-Di Dong , Hernando P. Bacosa","doi":"10.1016/j.ecss.2025.109414","DOIUrl":"10.1016/j.ecss.2025.109414","url":null,"abstract":"<div><div>Understanding the fate of mesoplastics is crucial for inferring microplastic pollution levels, as their degradation over time contributes significantly to microplastic accumulation. However, Philippine beaches, which gained international recognition for their beautiful landscape and crystal-blue waters, are poorly studied. We assessed meso- (5–25 mm) and large-microplastic (1–5 mm) accumulation in urban and rural Philippine beaches and their ecological risks. A total of 513 meso- and 180 large-microplastics (LMP) were identified across 30 sites, with mean concentrations of 45.5 ± 24.3 items/m<sup>2</sup> and 16.1 ± 0.190 items/m<sup>2</sup>, respectively. The plastic particles were confirmed using ATR-FTIR analysis. Expectedly, meso- and LMP abundances were significantly higher (p < 0.05) in urban than rural beaches, indicating anthropogenic pollution drivers. Dominant mesoplastics were primarily white in color (34.8 %), film-shaped (38 %), and measured 5–10 mm in size (35.1 %), with polypropylene (37.8 %) as the most prevalent polymer. Similarly, LMP were mainly white in color (68 %), foam-shaped (66.3 %), and measured 4.0–4.9 mm (34.8 %), with polystyrene (66.3 %) as the dominant polymer, showing industrial, domestic, and recreational impacts. Additionally, a strong relationship between meso- and LMP abundance suggests similar contamination sources and potential plastic fragmentation. Their proportional distribution in fine and coarse sands further indicates similar accumulation patterns. Overall, urban beaches are pollution hotspots, emphasizing the need for targeted interventions to mitigate plastic pollution impacts on Philippine beaches and the marine environment.</div></div>","PeriodicalId":50497,"journal":{"name":"Estuarine Coastal and Shelf Science","volume":"323 ","pages":"Article 109414"},"PeriodicalIF":2.6,"publicationDate":"2025-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144470890","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Sharyn M. Hickey , Amy Stone , Ben Radford , Catherine E. Lovelock
{"title":"Multidecadal mapping of arid intertidal ecosystems reveals a dynamic mosaic of habitats north-western Australia","authors":"Sharyn M. Hickey , Amy Stone , Ben Radford , Catherine E. Lovelock","doi":"10.1016/j.ecss.2025.109401","DOIUrl":"10.1016/j.ecss.2025.109401","url":null,"abstract":"<div><div>Intertidal areas are dynamic environments and represent an important ecotone, with flora and fauna adapted to variation in tidal inundation. In arid coastlines there is complexity in tidal inundation, due to high temperatures and evaporative conditions that strongly influence the distribution of biota. The Pilbara coastline in north-west Australia is one of seven arid mangrove regions that also comprises extensive saltmarsh, cyanobacterial mats, and salt flats. Spatial extent and temporal mapping of these habitats has not previously been conducted. In this study, we undertake eight time-point models of 10 habitat classes over 400 km of the Pilbara coastline. Using a combination of Landsat 5, 7, 8 and 9 satellite scenes and high-resolution aerial images we develop a spatial-extent of predicted habitats observing the dynamic nature of the habitats, particularly for the cyanobacterial mat habitat. We find that cyanobacterial mats comprise the largest spatial extent of the intertidal habitat classes covering on average 34 % of the intertidal region, double that of the mangrove area (16 %). Across the time-points, pixels transitioning between high intertidal salt flat, cyanobacterial mat, and areas with bright salt were the largest combination of classes, and the second largest class overall (behind coastal vegetated habitats). This research comprehensively models the extent of the habitats that comprise the high intertidal zone of the Pilbara Coast that is a globally significant area of hypersaline habitat providing an important baseline and insights into the impacts of climate on arid intertidal habitats.</div></div>","PeriodicalId":50497,"journal":{"name":"Estuarine Coastal and Shelf Science","volume":"323 ","pages":"Article 109401"},"PeriodicalIF":2.6,"publicationDate":"2025-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144522091","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Marianela Zanolla , Claudia L. Cara-Ortega , Víctor Sanz-Fernández , Dagmar B. Stengel
{"title":"Distribution pattern and biochemical variability of Irish invasive seaweed across a spatial gradient","authors":"Marianela Zanolla , Claudia L. Cara-Ortega , Víctor Sanz-Fernández , Dagmar B. Stengel","doi":"10.1016/j.ecss.2025.109406","DOIUrl":"10.1016/j.ecss.2025.109406","url":null,"abstract":"<div><div>This study updates the distribution of seaweed invasive alien species (IAS) in Ireland and demonstrates the natural spatial variation of their phenolic compounds and fatty acid profiles, coupled with an assessment of biomass availability. We examined the intertidal area of 68 coastal locations and detected the presence of six IAS, but abundant populations (30–50 % cover) were only recorded for <em>Sargassum muticum</em> in some western and southern locations along the Irish coast. However, the fact that so many invasive species were widely distributed represents a dormant threat to Irish coastal ecosystems. Regarding distribution, we detected a spatial expansion of <em>Colpomenia peregrina</em> and <em>Codium fragile</em>, while a contraction was recorded for <em>S. muticum</em> and <em>Asparagopsis armata</em>. <em>Undaria pinnatifida</em> represents a recent introduction, and <em>Gracilaria vermiculophylla</em> is spreading to new locations in the south and west. In general, saturated fatty acid content was high in <em>C. fragile</em> and <em>C. peregrina</em> samples, and higher monounsaturated fatty acid content occurred in the latter. <em>Sargassum muticum</em> and <em>G. vermiculophylla</em> presented more polyunsaturated fatty acids and n-3 fatty acids (together with <em>C. fragile</em>). Statistical analyses showed that, for to <em>S. muticum</em>, higher water temperatures decreased metabolite content in all areas sampled, and higher concentrations of metabolites were generally found in northern populations. However, biomass was not abundant at these sites, which poses challenges facing valorisation of these natural resources. This study provides important baseline information of fatty acid profiles and phenolic content of Irish IAS, an essential preliminary step in industrial sourcing of marine bioactive metabolites.</div></div>","PeriodicalId":50497,"journal":{"name":"Estuarine Coastal and Shelf Science","volume":"323 ","pages":"Article 109406"},"PeriodicalIF":2.6,"publicationDate":"2025-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144549816","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Alice Reis , Amanda Martins , Yuri Costa , André Rovai , Francisco Barros
{"title":"Understanding saltmarsh distribution and mangrove co-occurrence at tropical estuaries","authors":"Alice Reis , Amanda Martins , Yuri Costa , André Rovai , Francisco Barros","doi":"10.1016/j.ecss.2025.109413","DOIUrl":"10.1016/j.ecss.2025.109413","url":null,"abstract":"<div><div>Saltmarshes are coastal ecosystems composed of herbaceous vegetation that provide nursery grounds for several estuarine species, coastal protection by wave attenuation, carbon sinks, and facilitate mangrove propagules establishment and survival. Saltmarshes are studied mainly in high-latitude estuarine regions of developed countries, while in tropical systems, saltmarshes are widely overlooked due to the dominance of mangrove forests. This study aimed to map the occurrence of saltmarshes in three tropical estuaries and assess mangrove propagules and seedlings within tropical <em>Spartina</em> spp. dominated saltmarshes. We tested the hypotheses that (1) the abundance of propagules and seedlings within saltmarshes would be higher than in non-vegetated intertidal flats and (2) mangrove propagules and seedlings abundance would be higher in denser and taller saltmarshes. Mangrove propagules and seedlings of <em>Avicennia</em> spp., <em>Laguncularia racemosa,</em> and <em>Rhizophora mangle</em> were mainly found within saltmarshes when compared to non-vegetated adjacent tidal flats. There was no significant effect of saltmarsh height and density on mangrove seedling abundance. The present study showed that saltmarsh facilitates mangrove colonization in mangrove-dominated regions. Future studies on tropical estuaries should assess if mangrove propagules and seedlings found on saltmarsh patches achieve the reproductive phase and promote the progradation of mangrove forests.</div></div>","PeriodicalId":50497,"journal":{"name":"Estuarine Coastal and Shelf Science","volume":"323 ","pages":"Article 109413"},"PeriodicalIF":2.6,"publicationDate":"2025-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144501897","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Hye-Mi Lee , Hyun-Sil Kang , Nobuhisa Kajino , Hyun-Ki Hong , Young-Ghan Cho , Kwang-Sik Choi
{"title":"First report of mass mortality event caused by Eomarteilia granula in Manila clam Ruditapes philippinarum reared in subtidal and bottom cages on the south coast of Korea","authors":"Hye-Mi Lee , Hyun-Sil Kang , Nobuhisa Kajino , Hyun-Ki Hong , Young-Ghan Cho , Kwang-Sik Choi","doi":"10.1016/j.ecss.2025.109408","DOIUrl":"10.1016/j.ecss.2025.109408","url":null,"abstract":"<div><div>During a comparative experiment assessing the growth performance and health of the Manila clam <em>Ruditapes philippinarum</em> in subtidal suspended cage and intertidal bottom cage culture system, we observed an unexpected decline in condition index alongside a sharp increase in mortality. Histological examination revealed a progressive surge in infection prevalence of <em>Eomarteilia granula</em> in the digestive glands, coinciding with the mortality trends. As the infection advanced, histological sections showed progressive tissue alterations within the digestive gland tubules, including epithelial thinning, necrosis, and complete architectural collapse in severely affected individuals—indicative of profound structural disruption. To assess the pathological impact of this parasite, we applied a histopathological condition index (HPI), calculated exclusively for digestive gland tubules due to the parasite's strict tissue tropism. HPI values increased markedly toward the end of the experiment, indicating severe tissue damage. These findings suggest that <em>E. granula</em>-induced impairment of digestive gland function likely contributed to the observed mortality. This study represents the first documented case of <em>E. granula</em>-associated mass mortality in Manila clams. While the prevalence of <em>E. granula</em> has remained low in natural Asian environments, our results highlight that intensive culture systems may amplify infection severity and associated mortality risks.</div></div>","PeriodicalId":50497,"journal":{"name":"Estuarine Coastal and Shelf Science","volume":"323 ","pages":"Article 109408"},"PeriodicalIF":2.6,"publicationDate":"2025-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144365353","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Bottom wave streaming intensifies a nearshore upwelling front","authors":"Jiehua Wu , Peng Wang","doi":"10.1016/j.ecss.2025.109410","DOIUrl":"10.1016/j.ecss.2025.109410","url":null,"abstract":"<div><div>Coastal upwelling front is a crucial physical process on continental shelves, influencing coastal material transport, air-sea interactions, fisheries, and ecological environments. While previous studies have shown that coastal upwelling front is influenced by various factors, such as winds and topography, relatively little attention has been paid to surface waves, particularly bottom wave streaming. Bottom wave streaming is a wave-averaged Eulerian current in the direction of wave propagation, due to bottom friction on waves. It can affect bottom cross-shore transport and vertical mixing, potentially affecting the coastal upwelling front. In this study, we focus on the effects of bottom wave streaming on a wind-driven coastal upwelling front over an idealized continental shelf using a coupled wave-current model. Our results show that bottom wave streaming weakens the along-shelf current through increased momentum dissipation, thereby reducing bottom onshore Ekman transport. As a consequence, less cold, deep water is transported shoreward compared to scenarios without bottom wave streaming. On the other hand, the enhanced vertical mixing associated with bottom wave streaming facilitates the outcrop of bottom cold water, strengthening surface temperature gradients and thereby the upwelling front. Further, sensitivity tests reveal that the bottom wave streaming-induced intensification of upwelling front is robust across different wave directions, heights, and periods. This study highlights the critical role of bottom wave streaming in shaping the nearshore upwelling front, emphasizing its importance in the study of upwelling dynamics and material exchange.</div></div>","PeriodicalId":50497,"journal":{"name":"Estuarine Coastal and Shelf Science","volume":"323 ","pages":"Article 109410"},"PeriodicalIF":2.6,"publicationDate":"2025-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144470889","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pradipta Biswas , Robert R. Twilley , André S. Rovai , Alexandra Christensen , Zoë I. Shribman , Sabarethinam Kameshwar
{"title":"Incorporating uncertainty in a wetland soil accretion model (NUMAN 2.0) to test generality across coastal environmental settings of south Florida","authors":"Pradipta Biswas , Robert R. Twilley , André S. Rovai , Alexandra Christensen , Zoë I. Shribman , Sabarethinam Kameshwar","doi":"10.1016/j.ecss.2025.109407","DOIUrl":"10.1016/j.ecss.2025.109407","url":null,"abstract":"<div><div>Understanding the relative contributions of aboveground and belowground processes to soil accretion and carbon density may explain carbon sequestration rates in mangroves across different coastal environmental settings. We reformulated the nutrient mangrove model (NUMAN) by improving algorithms and uncertainty analysis using literature values and site-specific observations to evaluate the relative contributions of organic and inorganic sedimentation for three mangrove sites with marked soil fertility gradients reflected by nitrogen-to-phosphorus (N:P) ratios including Shark River (N:P = 28), Rookery Bay (N:P = 54–78), and Taylor Slough (N:P = 102) in south Florida. NUMAN 2.0 considers cellulose as a refractory organic-matter sub-pool and simultaneously incorporates coarse-root inputs to soil formation. The model simulation also captures root necromass accumulation. Monte Carlo (MC) simulations (N = 1000 per site) were conducted to capture uncertainty by treating five key parameters as random variables: lignin content in fine, coarse, and large roots; inorganic sediment loading; and root biomass at the surface. With robust mass balancing of organic matter, NUMAN 2.0 generates precise predictions of surface accretion and carbon density. NUMAN 2.0 simulations estimated mean (standard deviation) soil carbon sequestration rates at 130.1 (55.4) for Shark River, 72.5 (3.7) for Rookery Bay, and 130.0 (83.9) <span><math><mrow><mi>g</mi><mspace></mspace><msup><mi>m</mi><mrow><mo>−</mo><mn>2</mn></mrow></msup><mspace></mspace><mi>y</mi><msup><mi>r</mi><mrow><mo>−</mo><mn>1</mn></mrow></msup></mrow></math></span> for Taylor Slough, compared to field values of 123.0, 86.0, and 108.8 (8.7) <span><math><mrow><mi>g</mi><mspace></mspace><msup><mi>m</mi><mrow><mo>−</mo><mn>2</mn></mrow></msup><mspace></mspace><mi>y</mi><msup><mi>r</mi><mrow><mo>−</mo><mn>1</mn></mrow></msup></mrow></math></span>, respectively. Simulation experiments with NUMAN 2.0 suggest that belowground organic matter dominates soil formation and carbon sequestration generally in coastal environmental settings with little allochthonous input such as carbonate settings, while wood litterfall should dominate soil organic matter in top 10 cm in estuaries, and bays.</div></div>","PeriodicalId":50497,"journal":{"name":"Estuarine Coastal and Shelf Science","volume":"323 ","pages":"Article 109407"},"PeriodicalIF":2.6,"publicationDate":"2025-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144501851","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Switch from source to Sink: Greenhouse gas fluxes in razor clam aquaculture ponds at different statuses of mangrove restoration","authors":"Yiwen Chen, Jialin Zhang, Peiyang Qiao, Sipan Wu, Xiufan Peng, Luzhen Chen","doi":"10.1016/j.ecss.2025.109403","DOIUrl":"10.1016/j.ecss.2025.109403","url":null,"abstract":"<div><div>Aquaculture ponds significantly contribute to greenhouse gas (GHG) emissions. Ecological restoration of these ponds in China's coastal regions involves transitioning through stages of active cultivation, abandonment, and recovery to restore them into vibrant mangrove forests. However, the GHG emissions across different restoration stages remain under-researched. To bridge this gap, this study monitored carbon dioxide (CO<sub>2</sub>) and methane (CH<sub>4</sub>) emissions at the water-air interface over a year in Zhangjiang Mangroves, focusing on razor clam aquaculture ponds in three distinct stages of restoration.</div><div>Our study revealed that ponds were significant CH<sub>4</sub> emitters, with abandoned ponds emitting the least (0.0049 tCH<sub>4</sub> ha<sup>−1</sup> yr<sup>−1</sup>), followed by restored ponds (0.0061 tCH<sub>4</sub> ha<sup>−2</sup> yr<sup>−1</sup>), while active culturing ponds had the highest emissions (0.0078 tCH<sub>4</sub> ha<sup>−2</sup> yr<sup>−1</sup>). Both active culturing and abandoned ponds were net carbon sources, emitting 4.81 tCO<sub>2</sub> ha<sup>−2</sup> yr<sup>−1</sup> and 1.04 tCO<sub>2</sub> ha<sup>−2</sup> yr<sup>−1</sup> respectively, while restored ponds served as a carbon sink, with a net uptake 0.43 tCO<sub>2</sub> ha<sup>−2</sup> yr<sup>−1</sup> throughout the year. Temperature emerges as the most influential factors for both CO<sub>2</sub>, and CH<sub>4</sub> emissions. Furthermore, the carbon sequestration capacity of mangrove forests offset 282.7 % of the total CO<sub>2</sub>-equivalent GHG flux from the restored ponds. As restoration progresses, the cessation of aquaculture and vegetation recovery can effectively mitigate the greenhouse effect from pond cultivation by 73.8 %. This study provides vital data for China's coastal aquaculture carbon emission inventory and insights into GHG changes following the conversion of aquaculture ponds to mangrove forests, highlighting the significance of mangrove restoration in reducing emissions.</div></div>","PeriodicalId":50497,"journal":{"name":"Estuarine Coastal and Shelf Science","volume":"323 ","pages":"Article 109403"},"PeriodicalIF":2.6,"publicationDate":"2025-06-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144331146","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Where were the Caribbean mangroves during the Last Glacial Maximum? A preliminary microtopographical appraisal","authors":"Valentí Rull","doi":"10.1016/j.ecss.2025.109404","DOIUrl":"10.1016/j.ecss.2025.109404","url":null,"abstract":"<div><div>During the Last Glacial Maximum (LGM), when global sea levels dropped by ∼132 m, the Caribbean continental shelf was fully exposed, which drastically reduced the flat topographical habitat necessary for mangrove growth. It has been proposed that mangroves survived in flat microsites beyond the shelf break and later expanded from these microrefugia to their current distribution after the LGM. However, this hypothesis remains untested. This study aims to identify potential refugia by locating flat areas around the −132 m isobath using Global Multiresolution Topography (GMRT) images. A significant ∼200-km-long potential refugium was identified on the northern Trinidad (NT) shelf, along with several scattered kilometer-scale microrefugia near the Cariaco Basin (CB) in northeastern Venezuela. Additionally, two isolated prospective microrefugia were detected in northern Colombia (NC) and western Hispaniola (WH). The remaining LGM Caribbean coasts were considered unsuitable for mangrove growth. The NT refugium, along with the CB microrefugia, may have served as the primary sources for subsequent mangrove expansion. This expansion was likely facilitated by postglacial sea-level rise and the SE-NE Caribbean Current (CC), which would have acted as a major agent for propagule dispersal. This microtopographical survey not only supports the microrefugial hypothesis but also narrows the focus to the most promising areas, significantly reducing the time, effort and resources required for future seismic and coring campaigns.</div></div>","PeriodicalId":50497,"journal":{"name":"Estuarine Coastal and Shelf Science","volume":"323 ","pages":"Article 109404"},"PeriodicalIF":2.6,"publicationDate":"2025-06-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144322922","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}