Estuarine Coastal and Shelf Science最新文献

{"title":"Long-term variation in ghost crab metapopulations: From pre-pandemic degrading scenario to post-pandemic recovery with the establishment of a protected area","authors":"Letícia Arcelino ,&nbsp;Carlos Alberto de Moura Barboza ,&nbsp;Phillipe Mota Machado ,&nbsp;Vitor Figueira Arueira ,&nbsp;Ilana Rosental Zalmon ,&nbsp;Leonardo Lopes Costa","doi":"10.1016/j.ecss.2025.109345","DOIUrl":"10.1016/j.ecss.2025.109345","url":null,"abstract":"<div><div>The ghost crab Ocypode quadrata (Fabricius, 1787) is adversely affected by anthropogenic impacts on western Atlantic sandy beaches, resulting in reduced burrow density and diameter. However, during periods of reduced human activity, as observed during the COVID-19 pandemic, ghost crab metapopulations may rebound. This study aimed to determine whether the recovery of the ghost crab metapopulation observed during the pandemic persisted into the post-pandemic period and following the creation of a locally managed Environmental Protected Area (EPA). Monthly data on burrow abundance and opening diameter from the lockdown (2020–2021) and post-pandemic (2022–2023) periods were analyzed and compared with historical data from pre-pandemic times (2013–2019) across areas with varying levels of urbanization and human disturbances. We hypothesized that burrow abundance and burrow opening diameter in urbanized areas decrease in the post-pandemic period compared to the lockdown even after the establishment of the EPA. A significant increase in burrow density in the most urbanized areas was observed during the lockdown and post-pandemic periods compared to pre-pandemic times, likely attributed to the \"anthropause\" and the restriction of activities such as vehicle traffic within the EPA. However, the most urbanized areas recorded the smallest burrows even during the lockdown and post-pandemic periods compared to non-urbanized areas, suggesting that recreational activities still affect individual energy budget and growth. Our findings highlight the importance of EPAs and mitigation actions, such as reducing degrading human activities, for ghost crab metapopulations and beach ecological integrity. Thus, balancing recreational activities and biodiversity conservation is feasible in these socio-ecological ecosystems.</div></div>","PeriodicalId":50497,"journal":{"name":"Estuarine Coastal and Shelf Science","volume":"321 ","pages":"Article 109345"},"PeriodicalIF":2.6,"publicationDate":"2025-05-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143943707","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":"Assessment of feeding patterns of the mottled scorpionfish (Pontinus clemensi) in the Galapagos Marine Reserve","authors":"Cisne Zambrano-Zamora ,&nbsp;María del Mar Quiroga-Samaniego ,&nbsp;Jorge Ramírez-González ,&nbsp;Solange Andrade-Vera ,&nbsp;José R. Marín-Jarrín ,&nbsp;Diego Páez-Rosas","doi":"10.1016/j.ecss.2025.109338","DOIUrl":"10.1016/j.ecss.2025.109338","url":null,"abstract":"<div><div>The mottled scorpionfish (<em>Pontinus clemensi</em>) is a species of high economic, cultural and ecological value in the archipelago, which is exposed to possible overexploitation for local consumption. Trophic information is essential not only to provide insights into their role in the ecosystem but also provides a theoretical basis for the management of these resources. We determined the feeding patterns of <em>P. clemensi</em> applying complementary techniques of stomach content analysis (SCA) and stable isotope analysis (SIA). Sampling was conducted at four sites of fishing importance within the Galpagos Marine Reserve (GMR) between November 2017 and April 2018, obtaining 105 stomachs and muscle samples. The Prey-specific Index of Relative Importance (%PSIRI) determined <em>Anchoa ischana</em> as the most important prey, with differences (p &lt; 0.05) in its consumption between seasons, sex, and life stages. However, the δ¹³C values did not show differences (p &gt; 0.05) between sexes and life stages, suggesting the use of the same feeding areas. The δ¹⁵N values showed differences (p &lt; 0.05) between seasons and life stages, pointing towards the consumption of prey from different trophic levels depending on the seasonality and size of the individual. A specialist-type feeding strategy was determined in most categories (Bi &lt; 0.6) except for juveniles that display a possible generalist tendency (Bi = 0.64). The calculated trophic level (TL) places it as a tertiary-secondary consumer (SCA = 4.26, SIA = 3.72), characterized by consuming prey of similar trophic position (OI = 0.14), which led to a high isotopic overlap between groups. Our results constitute baseline information on the feeding patterns of <em>P. clemensi</em> in the GMR and highlights the value of ecological studies in the ecosystem-based fisheries management.</div></div>","PeriodicalId":50497,"journal":{"name":"Estuarine Coastal and Shelf Science","volume":"321 ","pages":"Article 109338"},"PeriodicalIF":2.6,"publicationDate":"2025-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143917845","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":"Exploring the land-ocean biogeochemical and microbial connectivity in the Ría de Vigo (NW Iberian Peninsula) through submarine groundwater discharge","authors":"Cristina Bernal ,&nbsp;Eva Teira ,&nbsp;Elisa Calvo-Martin ,&nbsp;Maider Justel-Diez ,&nbsp;Xosé Antón Álvarez-Salgado ,&nbsp;Carlos Rocha ,&nbsp;Mercedes de la Paz ,&nbsp;Marta Álvarez ,&nbsp;J. Severino P. Ibánhez","doi":"10.1016/j.ecss.2025.109339","DOIUrl":"10.1016/j.ecss.2025.109339","url":null,"abstract":"<div><div>Increasing evidence demonstrates the widespread occurrence of submarine groundwater discharge (SGD) in coastal zones, where it may influence biogeochemistry and microbial ecology. Here, we analyze the biogeochemical composition and microbial communities across diverse aquatic environments in a highly productive coastal system (Ría de Vigo, NW Iberian Peninsula), influenced by significant fresh SGD, to assess the extent of microbial and biogeochemical connectivity—i.e., mass transfer—among them. Samples were collected from surface and deep porewaters from two subterranean estuaries (STEs), surface seawater, riverine water, and continental groundwater. These samples were analyzed for a comprehensive set of microbial and biogeochemical variables, including radioisotopes used as SGD tracers. A significant correlation between SGD tracers and carbonate system parameters, N₂O, and CH₄ concentrations in surface seawater indicates SGD influences biogeochemistry of the embayment. However, some of these solutes do not originate from continental groundwater but are produced in the local STEs, which act as biogeochemical reactors modifying fresh SGD. The findings also reveal highly diverse microbial communities, with higher diversity in STEs due to the variety of niches present. Indicator taxa included the phyla Euryarchaeota, Chloroflexi, Omnitrophicaeota, and the family Nitrosopumilaceae in STEs; the phylum Cyanobacteria and the family Burkholderiaceae in freshwater endmembers; and the Flavobacteriaceae and Cryomorphaceae families in seawater. Most operational taxonomic units (∼87 %) were unique to a single environment (river, continental groundwater, coastal water, or STE), showing STEs limit subterranean microbial transfer between groundwater and marine ecosystems. Our results highlight STEs as reservoirs of diversity and zones of intense biogeochemical reactivity.</div></div>","PeriodicalId":50497,"journal":{"name":"Estuarine Coastal and Shelf Science","volume":"322 ","pages":"Article 109339"},"PeriodicalIF":2.6,"publicationDate":"2025-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144189648","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":"Effects of regional oceanography and climate variability on larval connectivity of the wedge clam Donax hanleyanus in South American beaches","authors":"Erika Meerhoff ,&nbsp;Vincent Combes ,&nbsp;Ricardo Matano ,&nbsp;Nicolas Barrier ,&nbsp;Barbara C. Franco ,&nbsp;Alberto R. Piola ,&nbsp;Freddy Hernández-Vaca ,&nbsp;Omar Defeo","doi":"10.1016/j.ecss.2025.109346","DOIUrl":"10.1016/j.ecss.2025.109346","url":null,"abstract":"<div><div>The wedge clam, <em>Donax hanleyanus</em>, inhabits sandy beaches in the subtropical and temperate regions of the Atlantic coast of South America. Its distribution spans over 20 degrees of latitude from Brazil to Argentina, with the southernmost part of its range being influenced by the Rio de la Plata (RdlP) estuary, which limits the southward larval expansion. We used an individual-based model (IBM) to assess the larval connectivity patterns of the wedge clam during the period 2000–2012. The IBM combines a 3D hydrodynamic model with a biological sub-model that considers larval mortality due to low salinity (&lt;7, and &lt;9) and sea surface temperature range (high &gt;30 °C or low &lt;9 °C). The main larval connectivity patterns were observed near the release/recruitment areas, suggesting a high potential for self-recruitment. Based on the IBM and adult abundance data, we also identified the likely source and sink areas within this metapopulation. Source beach areas were Navegantes and Cassino in Brazil (from 26.3° S to 34.34°S), Arachania in Uruguay (34.56°S), and Santa Teresita in Argentina (37.15°S). A low probability of larval transport towards the poleward limit of the species' distribution was observed, supporting an irregular recruitment pattern typical of sink populations located at the edge of the distribution range of metapopulations. Larval mortality due to warm or cold waters did not affect connectivity patterns for this subtropical species. Southward larval transport across the RdlP estuary (from Uruguayan to Argentine beaches) only occurred for larvae released on early January 2011, concurrently with the strongest La Niña year observed during the study period. In light of a changing climate, marked by potential increases in extreme La Niña events and a poleward shift of atmospheric circulation patterns over the South Atlantic, we anticipate a strengthening of larval transport across the RdlP and a subsequent poleward expansion of the species’ distribution range.</div></div>","PeriodicalId":50497,"journal":{"name":"Estuarine Coastal and Shelf Science","volume":"321 ","pages":"Article 109346"},"PeriodicalIF":2.6,"publicationDate":"2025-05-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143931992","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":"Changes in the community composition of beach wrack macrophytes along thermal and latitudinal gradients","authors":"Fabien Verniest ,&nbsp;Elisa Alonso Aller ,&nbsp;Pauline Poisson ,&nbsp;Martin Thibault ,&nbsp;Isabelle Le Viol ,&nbsp;Christian Kerbiriou","doi":"10.1016/j.ecss.2025.109342","DOIUrl":"10.1016/j.ecss.2025.109342","url":null,"abstract":"<div><div>Marine species and ecosystems are highly threatened by many anthropogenic drivers of biodiversity loss, among which the various components of climate change play a key role. Bending the curve of marine biodiversity loss requires the development of decision-making tools, such as indicators that provide information on community responses to climatic change. Although monitoring marine environments, such as benthic habitats, is highly challenging, beach wrack monitoring may provide an alternative and complementary approach to inform changes in proximate intertidal and subtidal habitats under anthropogenic threats. However, the relationship between macrophyte in beach wrack and benthic macrophyte is not fully understood. In particular, the composition of beach wrack macrophyte communities in relation with climate has not been explored yet, although such research is a prerequisite for investigating the ability of macrophyte communities in beach wrack to monitor composition changes of benthic macroalgal and seagrass communities in the face of climate change. Here, we assessed the thermal and spatial patterns of thermal affinity of macroalgae and seagrass communities (84 taxa) in beach wrack sampled at 172 sites (from Saint-Jean-de-Luz, latitude 43.39°N, to Calais, latitude 50.89°N) along the Channel and Atlantic French coast. We also investigated the contribution of taxa to these patterns, and evaluated the latitudinal patterns of abundance of the most and least contributing taxa. We found that thermal affinity of macrophyte communities in beach wrack increased with sea-surface temperature and decreased with latitude. Latitudinal patterns were also identified at smaller spatial scales. Our findings, that are consistent with previously documented macroecological patterns of benthic macrophytes, suggest that beach wrack might provide insights into proximate benthic macrophyte communities, especially their composition in light of climate warming. We recommend further investigations to ensure the relevance of developing indicators of benthic habitats based on beach wrack.</div></div>","PeriodicalId":50497,"journal":{"name":"Estuarine Coastal and Shelf Science","volume":"321 ","pages":"Article 109342"},"PeriodicalIF":2.6,"publicationDate":"2025-05-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143931962","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":"Shoreline movements around small reef islands of the Kalayaan Island Group, West Philippine Sea","authors":"Jeffrey Munar,&nbsp;Anne Drew Carrillo,&nbsp;Laura David,&nbsp;Fernando Siringan","doi":"10.1016/j.ecss.2025.109343","DOIUrl":"10.1016/j.ecss.2025.109343","url":null,"abstract":"<div><div>Reef islands have highly dynamic beaches, with shorelines that shift easily due to changes in wave patterns influenced by wind conditions, typhoons, and sea-level. Habitat conditions within and around reef island systems also impact shoreline integrity. Mapping shoreline movement patterns is essential for understanding their evolution and potential responses to climate and human-induced changes.</div><div>Shoreline positions for several islands in the Kalayaan Islands, West Philippine Sea—including Pag-asa, Parola, Kota, Likas, and Lawak—were traced from satellite images obtained via Google Earth, covering the period from 2005 to 2023. These are complemented by field-derived shoreline positions acquired during 2022. Statistics were calculated using the Digital Shoreline Analysis System (DSAS). Patterns and rates of shoreline change vary among the reef islands. Net accretion has taken place in Parola Island while the rest of the islands have net erosion. Erosion rates are generally high on the eastern sections of the islands, while the southwest sections experience the highest accretion rates. Islands positioned more east of their atolls show greater erosion. The overall shoreline patterns are attributed to the reduced southwest (SW) monsoon and relatively constant northeast (NE) monsoon intensities during the period covered by this study. Consequently, the southwest sediment drift driven by the NE winds dominated over the northeastward sediment drift driven by the SW winds.</div><div>Shorelines also respond to sudden natural and anthropogenic stressors. Episodes of high wave energy conditions, Typhoon Hagupit in 2014 and frequent typhoons in 2017, caused substantial losses in island area. Vegetation Index Green (VI_green) was also computed to assess the extent of vegetation coverage. Losses in vegetation cover also correlate with losses in the island area. A disturbance that likely tempered erosion, temporarily, is the elevation of sediment input to the coast caused by extensive dredging on the reef flat between 2013 and 2014. Dredging exposed and released sediment to the reef. However, this activity reduced the living coral cover and effectively increased the water depth on the reef flat. Consequently, this will decrease the reef's ability to sustain sediment supply to the island in the long term. These various natural and anthropogenic impacts are vital in managing limited sediment resources in light of rising sea levels on small reef island systems.</div></div>","PeriodicalId":50497,"journal":{"name":"Estuarine Coastal and Shelf Science","volume":"321 ","pages":"Article 109343"},"PeriodicalIF":2.6,"publicationDate":"2025-05-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143936876","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":"Comparisons between estuary-associated ichthyofaunas in ecoregions around the Indian Ocean","authors":"Alan K. Whitfield ,&nbsp;Trevor D. Harrison ,&nbsp;James R. Tweedley","doi":"10.1016/j.ecss.2025.109335","DOIUrl":"10.1016/j.ecss.2025.109335","url":null,"abstract":"<div><div>This review examines possible fish colonisation processes that started in the Early Jurassic and gained momentum during the Cretaceous when plate tectonics and continental drift created the Indian Ocean between Africa, Madagascar, Asia and Australia. Initial colonisation of the newly created estuaries by fish is likely to have occurred during the Devonian in eastern Gondwana when these land masses were confined to the temperate waters of the southern hemisphere. A major marine extinction event 372 Ma would probably have eliminated many of these taxa from those estuaries. Tropical marine fish families from the Tethys Sea region would then have used the epicontinental seaways between Africa, Madagascar, India and Australia to colonise the estuaries on these drifting land masses. Speciation by some of these tropical taxa would then have occurred such that the southern temperate waters became occupied by a less species rich cool-water ichthyofauna. A Bray-Curtis similarity matrix was created using the presence/absence of fish families and species from selected ecoregions around the Indian Ocean rim. These analyses showed that fish families present in estuaries on the eastern and western side of the Indian Ocean were over 74 % similar but that the species present were only 40 % similar. In terms of past and present geodispersal of fish taxa, the northern route through tropical coastal waters was always viable but long distance movements through the large central or southern parts of the Indian Ocean basin was not. In addition, dispersal of fish species across arid coastal ecoregions where estuaries are scarce appears to have limited the continuity of ichthyofaunal colonisation processes around the ocean rim.</div></div>","PeriodicalId":50497,"journal":{"name":"Estuarine Coastal and Shelf Science","volume":"321 ","pages":"Article 109335"},"PeriodicalIF":2.6,"publicationDate":"2025-05-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143943708","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":"Community metabolism and greenhouse gas emissions in abandoned tropical salt pans","authors":"Shu-Yen Huang ,&nbsp;Wei-Jen Lin ,&nbsp;Li-Hua Lee ,&nbsp;Hsing-Juh Lin","doi":"10.1016/j.ecss.2025.109327","DOIUrl":"10.1016/j.ecss.2025.109327","url":null,"abstract":"<div><div>A large area of coastal wetlands has been converted into solar salt pans over thousands of years. However, salt production declined significantly from the 20th century onward, leading to the abandonment of many salt pans globally. Coastal wetlands are generally recognized as blue carbon ecosystems, but little is known about the carbon flux of abandoned salt pans. This study aimed to assess the carbon flux of abandoned tropical salt pans, using a case study in Budai, southwestern Taiwan by measuring community metabolism and greenhouse gas (GHG) emissions. The results of community metabolism showed that the pelagic community of the salt pans is autotrophic, which is closely related to water chlorophyll <em>a</em> concentration. However, the benthic community is heterotrophic, which is influenced by water temperature and dissolved inorganic phosphorus concentration. The combined metabolism of pelagic and benthic communities in the salt pans exhibited an average carbon absorption of 111.5 g C m⁻² yr⁻¹. The results of GHG emissions measured with floating chambers indicated that the CO₂ flux into the salt pans averaged 139.3 g CO₂ m⁻² yr⁻¹, but a small amount of averaging 354.8 mg CH₄ m⁻² yr⁻¹ and 136.0 mg N₂O m⁻² yr⁻¹ was emitted from the salt pans. Consequently, the net GHG balance indicated that the salt pans serve as systems for removing GHG at an average rate of 92.6 g CO₂e m⁻² yr⁻¹. The CO₂ removal capacity of abandoned tropical salt pans performed better than that of unvegetated coastal wetlands, showing the potential to mitigate climate change.</div></div>","PeriodicalId":50497,"journal":{"name":"Estuarine Coastal and Shelf Science","volume":"321 ","pages":"Article 109327"},"PeriodicalIF":2.6,"publicationDate":"2025-05-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143924233","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":"Constancy and change in macrobenthic abundance, biodiversity and assemblage structure along the axis of a flood-tidal sand delta","authors":"R.S.K. Barnes","doi":"10.1016/j.ecss.2025.109326","DOIUrl":"10.1016/j.ecss.2025.109326","url":null,"abstract":"<div><div>Flood-tidal deltas commonly occur along microtidal coasts in the mouths of those inlets kept open by tidal currents, but they have seldom been studied ecologically. Such a delta of fine sand occurs in the Knysna estuarine bay, South Africa, extending for some 2 km upstream. Although macrofaunal assemblage metrics (overall abundance, observed and estimated species density, geometric mean morphospecies abundance, evenness, and patchiness) varied little along the deltaic axis, faunal composition changed markedly though without species replacement except in the paraonid polychaetes. Unusually, the sand was dominated by these paraonids (especially <em>Paradoneis lyra capensis</em>) and, over its proximal half, also by the amphipod <em>Urothoe pulchella</em>, but worms steadily increased in importance upstream whilst crustaceans decreased. Noteworthily, a psammodrilid was present - the first record from Africa. The flood-tidal shore fauna contrasted in composition with that of the facing ebb-channel shore (dominated by <em>Dipolydora</em>) and areas upstream of the mouth.</div></div>","PeriodicalId":50497,"journal":{"name":"Estuarine Coastal and Shelf Science","volume":"321 ","pages":"Article 109326"},"PeriodicalIF":2.6,"publicationDate":"2025-04-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143902401","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":"The role of retention processes in the coastal filter of the Oder River","authors":"Sophie Kache ,&nbsp;Iris Liskow ,&nbsp;Johannes Pein ,&nbsp;Mindaugas Žilius ,&nbsp;Maren Voss","doi":"10.1016/j.ecss.2025.109325","DOIUrl":"10.1016/j.ecss.2025.109325","url":null,"abstract":"<div><div>Riverine nutrient export significantly impacts coastal and shelf seas, causing eutrophication. However, nutrient export can be mitigated by the coastal filter function, potentially resulting in permanent removal of nutrients through denitrification. Besides removal, nutrients can also be retained in the coastal zone through assimilation, remineralisation or nitrification, with repeated recycling prolonging their availability to organisms. While removal processes have been extensively studied, their effect on the riverine dissolved inorganic nitrogen (DIN) loads reaching the coast may be small. There are only a few accurate estimates that include all processes of the coastal filter. In this study, nutrient concentrations and net autotrophic uptake rates in the water column, together with benthic NO₃⁻ reduction rates and solute fluxes across the sediment-water interface, were measured. We compared a lagoon with the open coast within the outflow area of the Oder River, one of the largest inflows to the southern Baltic Sea, over a seasonal cycle. Particle drift experiments using hydrodynamic model simulations of the Oder estuary yielded water residence times (WRT) along the outflow. In the lagoon, DIN concentrations, primary production and DIN uptake rates were higher than at the coastal station. The data suggested efficient DIN retention, as the majority of riverine DIN was assimilated (85 %), with a preference for NH₄⁺ over NO₃⁻ uptake. High retention in the lagoon was supported by long WRT of up to 180 days. In the open coast, productivity was lower due to continuous dilution of riverine nutrients by transport processes. The sediment served as a periodic source of nutrients for water column processes. Our data suggest that intense recycling in the water column and strong benthic-pelagic coupling promote a tightly coupled nitrification-denitrification, resulting in vital N removal rates in the sediment. Nevertheless, strong predominance of N retention processes, and specifically assimilation over N removal processes, illustrates that the former is an important component of the coastal filter function, as it provides substrates for nutrient removal (organic matter and NO₃⁻). These results extend the assessment of the effectiveness of the coastal filter and should be taken into account in further studies.</div></div>","PeriodicalId":50497,"journal":{"name":"Estuarine Coastal and Shelf Science","volume":"322 ","pages":"Article 109325"},"PeriodicalIF":2.6,"publicationDate":"2025-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144107837","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}