Limnology and Oceanography最新文献

{"title":"From surfacing to stranding: The origins and dispersal dynamics of a neustonic siphonophore","authors":"River B. Abedon, Mary Beth Decker, Casey W. Dunn, Samuel H. Church","doi":"10.1002/lno.70526","DOIUrl":"https://doi.org/10.1002/lno.70526","url":null,"abstract":"The Portuguese man‐o'‐war, <jats:italic>Physalia physalis</jats:italic> , regularly washes ashore on the US East Coast, but the physical and biological processes that determine when and where these animals strand are not well understood. Here we integrate iNaturalist observational data with a biologically‐informed particle‐tracking model to investigate the origins, dispersal, and stranding dynamics of <jats:italic>P. physalis</jats:italic> in the northwest Atlantic Ocean, building on recently reported population genomic structure. We find that juvenile <jats:italic>P. physalis</jats:italic> largely appear in Florida and on the Gulf of Mexico coast in winter months, and we use these findings to initialize particle‐tracking simulations based on observed juvenile distributions. Using models that incorporate <jats:italic>Physalia</jats:italic> drift hydrodynamics and high‐resolution forcing data, we show that <jats:italic>P. physalis</jats:italic> undergo rapid Gulf Stream transport along the US East Coast, with seasonal reproduction and onshore wind patterns shaping distinct regional stranding peaks, consistent with observed stranding data from iNaturalist. Our results suggest that seasonal Gulf Stream dynamics, including eddy activity, influence <jats:italic>P. physalis</jats:italic> transport in offshore regions and modulate strandings north of Cape Hatteras. Our study highlights the Gulf Stream's critical role in structuring planktonic distributions in the northwest Atlantic and reveals the transport dynamics that allow sailing species like <jats:italic>P. physalis</jats:italic> to disperse across vast regions of the ocean.","PeriodicalId":18143,"journal":{"name":"Limnology and Oceanography","volume":"12 1","pages":""},"PeriodicalIF":4.5,"publicationDate":"2026-10-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149221449","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Chronic exposure to a natural deoxygenation gradient underpins membrane and energy storage lipid restructuring in a benthic marine invertebrate","authors":"André L. R. Cuenca,&nbsp;Lauric Feugere,&nbsp;Diana Madeira,&nbsp;Geneviève J. Parent,&nbsp;Ludovic Pascal,&nbsp;Piero Calosi","doi":"10.1002/lno.70524","DOIUrl":"10.1002/lno.70524","url":null,"abstract":"<p>Lipids are central to animal physiology, underpinning energy storage, membrane architecture, and cell signaling. Targeted lipid studies in wild animals have already demonstrated that lipid adjustments, such as shifts in energy storage and membrane composition, are key molecular responses to environmental stressors. Yet, in situ lipidome-wide responses remain virtually unexplored in marine invertebrates, particularly in systems affected by chronic environmental deoxygenation. Here, we characterized for the first time the whole-body lipidome of the benthic marine annelid <i>Neoleanira tetragona</i> collected from sites across a naturally occurring deoxygenation gradient, with over 1700 lipids identified and quantified via untargeted high-resolution lipidomics. Individuals from less oxygenated areas exhibited an enrichment in triacylglycerols, indicating increased lipid storage, and membrane lipids with lower fatty acid unsaturation. In contrast, an enrichment of acylcarnitines in individuals from more oxygenated areas suggests increased lipid catabolism and turnover. We interpret these findings as a display of moderate capacity for lipidome-wide remodeling under chronic deoxygenation. We propose that this remodeling is due to physiological trade-offs between energy conservation, cellular protection and membrane architecture. Finally, by applying a breakpoint analysis we identify a potential molecular tipping point of O₂ availability (~ 56.6 ± 8.7 <i>μ</i>M), providing a first step toward mechanistically explaining a previously identified biogeochemical and community-level tipping point (~ 63 <i>μ</i>M) to environmental change. Our work demonstrates that lipid-wide remodeling represents a chronic physiological response to deoxygenation, detected in situ, offering a link between biochemical and community-level tipping points in a naturally exposed marine invertebrate.</p>","PeriodicalId":18143,"journal":{"name":"Limnology and Oceanography","volume":"71 10","pages":""},"PeriodicalIF":3.5,"publicationDate":"2026-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/lno.70524","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149172781","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Asymmetric responses of phytoplankton size structure across the track of Typhoon Yagi and the underlying mechanisms","authors":"Zihan Bai,&nbsp;Huabing Xu,&nbsp;Dongyang Fu,&nbsp;Guangjun Xu","doi":"10.1002/lno.70522","DOIUrl":"10.1002/lno.70522","url":null,"abstract":"&lt;p&gt;Typhoons disrupt upper-ocean dynamics through wind-driven mixing and upwelling, often producing cross-track asymmetry in the Northern Hemisphere. However, how such asymmetric physical forcing reshapes phytoplankton size structure remains poorly understood. This study integrates multi-sensor satellite observations with in situ size-fractionated chlorophyll &lt;i&gt;a&lt;/i&gt; (Chl &lt;i&gt;a&lt;/i&gt;) and nutrient measurements to examine the impacts of Typhoon Yagi (2024) in the northwestern South China Sea. Post-typhoon satellite observations showed cross-track physical contrasts: the right-of-track side exhibited stronger surface cooling (~ 3–4°C). In situ sampling on September 10 revealed strong biogeochemical contrasts across the track. Mean surface &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;msubsup&gt;\u0000 &lt;mi&gt;NO&lt;/mi&gt;\u0000 &lt;mn&gt;3&lt;/mn&gt;\u0000 &lt;mo&gt;−&lt;/mo&gt;\u0000 &lt;/msubsup&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt;$$ {mathrm{NO}}_3^{-} $$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt; and &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;msubsup&gt;\u0000 &lt;mi&gt;SiO&lt;/mi&gt;\u0000 &lt;mn&gt;3&lt;/mn&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mn&gt;2&lt;/mn&gt;\u0000 &lt;mo&gt;−&lt;/mo&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;/msubsup&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt;$$ {mathrm{SiO}}_3^{2-} $$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt; concentrations were higher on the right side, with the most robust cross-track contrast observed for &lt;span&gt;&lt;/span&gt;&lt;math&gt;\u0000 &lt;semantics&gt;\u0000 &lt;mrow&gt;\u0000 &lt;msubsup&gt;\u0000 &lt;mi&gt;SiO&lt;/mi&gt;\u0000 &lt;mn&gt;3&lt;/mn&gt;\u0000 &lt;mrow&gt;\u0000 &lt;mn&gt;2&lt;/mn&gt;\u0000 &lt;mo&gt;−&lt;/mo&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;/msubsup&gt;\u0000 &lt;/mrow&gt;\u0000 &lt;annotation&gt;$$ {mathrm{SiO}}_3^{2-} $$&lt;/annotation&gt;\u0000 &lt;/semantics&gt;&lt;/math&gt;. Total surface Chl &lt;i&gt;a&lt;/i&gt; was approximately 2.7-fold higher on the right side when all three left-side stations were included. At T6, elevated Chl &lt;i&gt;a&lt;/i&gt; co-occurred with an independently identified frontal and hydrographic anomaly. Size-fractionated Chl &lt;i&gt;a&lt;/i&gt; indicated that fractions &gt; 2 &lt;i&gt;μ&lt;/i&gt;m dominated on the right side, whereas the 0.2–2 &lt;i&gt;μ&lt;/i&gt;m fraction contributed approximately 70% at left-side Stas. T2 and T4. Notably, near-bottom total Chl &lt;i&gt;a&lt;/i&gt; on the left side peaked at T6, coincident with an intensified offshore sea surface temperature front. Satellite imagery on September 11–12 captured a delayed surface Chl &lt;i&gt;a&lt;/i&gt; enhancement. These results are consistent with cross-track differences in nutrient availability and upper-ocean physical structure associated with asymmetric typhoon forcing, while lateral advection and frontal convergence may have further modulated the observed Chl &lt;i&gt;a&lt;/i&gt; dist","PeriodicalId":18143,"journal":{"name":"Limnology and Oceanography","volume":"71 10","pages":""},"PeriodicalIF":3.5,"publicationDate":"2026-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149172929","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Macrozooplankton community structure and trophic interactions differ across a sub-Antarctic shelf break, independent of Antarctic krill","authors":"Anona N. Griffiths,&nbsp;Geraint A. Tarling,&nbsp;Anna Belcher,&nbsp;Sophie Fielding,&nbsp;Gabriele Stowasser,&nbsp;Emma L. Cavan","doi":"10.1002/lno.70518","DOIUrl":"10.1002/lno.70518","url":null,"abstract":"<p>The South Georgia continental shelf break is a highly productive and biodiverse region of the Southern Ocean, with abundant macrozooplankton forming the foundation of off- and on-shelf communities. Antarctic krill (<i>Euphausia superba</i>) are a major component of these communities and can dominate total biomass. In this study, we analyze a new 10-year timeseries of spatially varied net samples from summer campaigns spanning the South Georgia shelf region to examine patterns of variability in macrozooplankton species abundance on- and off-shelf in the austral summer. We found total net catch abundance was similar on- and off-shelf, with particularly high abundances when Antarctic krill were present. Overall trends showed on-shelf to be more variable in community composition, and more likely to contain high abundances of Antarctic krill. Community composition in the off-shelf environment remained consistent between sites and with time and was more species rich than the on-shelf community. Our analysis further revealed strong statistical associations in co-occurrence between certain taxa, which sometimes varied between on-shelf and off-shelf communities. In a number of instances, these associations reflect either feeding guilds (taxa with similar prey preferences) or predator–prey co-occurrence. Overall, although community composition differed between on-shelf and off-shelf environments, these compositions appeared to be relatively stable in space and time irrespective of the presence or absence of Antarctic krill. This finding, that the macrozooplankton communities appear relatively resilient to intra-decadal environmental fluctuations in abundance, has particular importance when considering the impact of rapid regional climate change and potential longer-term changes in the biomass of Antarctic krill on the wider South Georgia pelagic ecosystem.</p>","PeriodicalId":18143,"journal":{"name":"Limnology and Oceanography","volume":"71 10","pages":""},"PeriodicalIF":3.5,"publicationDate":"2026-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/lno.70518","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149172931","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Environmental filtering and spatial structuring differ among body-size and reproductive-mode groups of microcrustacean zooplankton in hardwater lakes","authors":"Buddhine Meegahage,&nbsp;Anas Mohamed Usoof,&nbsp;Erin Hillis,&nbsp;Zoraida Quiñones-Rivera,&nbsp;Kyle Hodder,&nbsp;Björn Wissel","doi":"10.1002/lno.70521","DOIUrl":"10.1002/lno.70521","url":null,"abstract":"<p>Local environmental factors are considered primary drivers of lake zooplankton community assembly, yet the roles of landscape factors and dispersal processes remain underexplored. We examined 78 hardwater lakes across the northern Great Plains (Canada) to evaluate how local (water chemistry, morphometric, and catchment characteristics), regional (climate and land use), and dispersal (spatial and lake isolation) factors explain microcrustacean zooplankton community composition. The region spans strong gradients in climate, water chemistry, and land use, making it well suited for disentangling multiscale influences. Taxa were grouped by body size and reproductive mode to evaluate trait-related differences in community–environment relationships. Ordination, spatial modeling, variation partitioning, and hierarchical partitioning revealed that local physicochemical variables, especially conductivity-related ions (sulfate and chloride), were the strongest predictors of community structure. Sulfate was most strongly associated with small-bodied taxa, while chloride showed opposite effects. Primary productivity and lake metabolism played secondary roles. Regional land-use and land-cover factors, indicative of terrestrial–aquatic coupling, had relatively minor importance. Climate variables did not emerge as significant predictors of species composition. Spatial structure and lake isolation suggested a role for dispersal-related processes in endorheic basins, with asexual species more strongly shaped by spatial factors than sexual ones. Compositional differences within body-size and reproductive groups were also associated with local urban and agricultural land use. These results highlight the value of trait-based groupings for interpreting ecological responses to environmental changes and emphasize the need to incorporate dispersal limitations into bioassessment and water management in lakes under increasing environmental pressures.</p>","PeriodicalId":18143,"journal":{"name":"Limnology and Oceanography","volume":"71 10","pages":""},"PeriodicalIF":3.5,"publicationDate":"2026-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/lno.70521","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149172933","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Thermogenic methane emissions from a glacier-fed river on the Tibetan Plateau","authors":"Xuexue Shang,&nbsp;Cuicui Mu,&nbsp;Ji Zhang,&nbsp;Mei Mu,&nbsp;Pengsi Lei,&nbsp;Yongqi Ge,&nbsp; Deji,&nbsp;Dandan Yang,&nbsp;He Sun,&nbsp;Jiaxin Yang,&nbsp;Lin Li,&nbsp;Tandong Yao","doi":"10.1002/lno.70520","DOIUrl":"https://doi.org/10.1002/lno.70520","url":null,"abstract":"<p>Climate change is increasing glacial retreat and melt in many mountain catchments, impacting biogeochemical processes and carbon fluxes. However, the potential for changes in methane (CH₄) emissions, sources and pathways in glacial-fed streams remains poorly constrained, largely due to sparse field observations. Here, we present three consecutive years of full-season field measurements of riverine CH₄ flux and stable carbon isotopes in the glacier-fed Lhasa River on the Tibetan Plateau. Our results reveal that riverine CH₄ fluxes rise markedly with proximity to glacier termini during the melt season, indicating substantial CH₄ emission potential in near-glacier river reaches. Diffusive and ebullitive emissions averaged 67 ± 33 and 183 ± 15 <i>μ</i>mol CH₄ m⁻² d⁻¹, respectively, demonstrating that ebullition dominates CH₄ release. High labile dissolved organic carbon and depleted δ¹³C-CH₄ indicate microbial dominance in the non-melt season, whereas enriched δ¹³C-CH₄ with elevated CH₄ saturations and spatial gradients indicate thermogenic sources during the melt season. Collectively, these lines of evidence illustrate that intensified glacier melt mobilizes CH₄ stored within glacial catchments and facilitates its release into the riverine system. This finding improves our understanding of CH₄ dynamics in glacier-fed aquatic systems and underscores the indispensable role of thermogenic CH₄ in constraining regional riverine CH₄ emission budgets.</p>","PeriodicalId":18143,"journal":{"name":"Limnology and Oceanography","volume":"71 10","pages":""},"PeriodicalIF":3.5,"publicationDate":"2026-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149205219","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Plankton nutritional quality outweighs isotopic trophic position in predicting food chain length across oceanic gradients","authors":"Danyang Li,&nbsp;Yi Long,&nbsp;Xiaofang Liu,&nbsp;Jun Sun","doi":"10.1002/lno.70523","DOIUrl":"10.1002/lno.70523","url":null,"abstract":"<p>The Eastern Indian Ocean exhibits a gradient from eutrophic nearshore to oligotrophic offshore conditions. The trophic structure of the planktonic food web in this region was investigated in spring 2022 using stable isotopes (δ¹³C, δ¹⁵N), biomass, and piecewise structural equation models (PSEM). Regional comparisons based on grouped stations showed that the equatorial zone was highly oligotrophic with the shortest food-chain length (FCL = 3.12), while the Bay of Bengal had the highest δ¹⁵N baseline and widest trophic range (0.10–4.0). The Sumatra upwelling and seamount area were nutrient-rich, supporting high particulate organic matter (POM), phytoplankton biomass, and top predators with longer food chains (FCL = 4.26 and FCL = 4.73, respectively). Isotopic niches were broadest in nearshore and upwelling zones but most constrained in oligotrophic waters. Using station-level data, the PSEM revealed that nitrite and chlorophyll <i>a</i> influenced isotopic patterns and FCL through POM carbon-to-nitrogen ratio (C : N), while plankton C : N played a significant role in extending the FCL. These findings emphasize how gradients shape food webs and the importance of upwelling and seamounts in supporting high-trophic-level species and carbon sequestration in the face of climate change.</p>","PeriodicalId":18143,"journal":{"name":"Limnology and Oceanography","volume":"71 10","pages":""},"PeriodicalIF":3.5,"publicationDate":"2026-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149172932","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"In situ degradation of kelp detritus: Implications for coastal carbon cycling","authors":"Jessica R. Kennedy,&nbsp;Cesar T. Facimoto,&nbsp;Alessandro Pisaniello,&nbsp;Kim M. Handley,&nbsp;Caitlin O. Blain","doi":"10.1002/lno.70517","DOIUrl":"10.1002/lno.70517","url":null,"abstract":"<p>Marine macroalgae (i.e., seaweeds) are crucial components of coastal carbon cycles and may be important contributors to marine carbon sequestration. Understanding the fate of macroalgal-derived carbon in marine systems requires an understanding of the degradation dynamics of macroalgae across environmental gradients. Therefore, we conducted an in situ kelp tissue degradation study in Tīkapa Moana/the Hauraki Gulf, Aotearoa New Zealand to assess the longevity of carbon contained within <i>Ecklonia radiata</i> kelp tissues. We utilized a set of six study sites which represent a natural gradient in turbidity to assess the influence of light availability on kelp decay dynamics, kelp tissue composition, and kelp surface/biofilm bacterial community. We found that half of kelp detritus disappeared within, on average, 58.37 ± 7.9 d. Light availability did not significantly influence kelp tissue longevity, although the shape of the kelp degradation curves differed across the light availability gradient. Kelp tissues maintained baseline concentrations of photosynthetic pigments throughout decomposition, while C : N (carbon : nitrogen) ratio decreased through degradation time at all sites. Degradation was associated with increased alpha diversity of kelp epiphytic bacterial communities and significant changes in kelp epiphytic bacterial community structure. This research shows that kelp tissues persist on subtidal rocky reefs in Tīkapa Moana/the Hauraki Gulf for no longer than 4 months, and that kelp degradation involves complex biogeochemical transformations that are not captured by biomass loss alone. These findings have critical implications for assessing the carbon sequestration potential of kelp forests in Aotearoa New Zealand and beyond.</p>","PeriodicalId":18143,"journal":{"name":"Limnology and Oceanography","volume":"71 10","pages":""},"PeriodicalIF":3.5,"publicationDate":"2026-10-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/lno.70517","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149172935","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Physical controls dominate stream metabolism and carbon cycling over nutrients and stoichiometry","authors":"James D. Kelley,&nbsp;Marguerite A. Xenopoulos","doi":"10.1002/lno.70519","DOIUrl":"10.1002/lno.70519","url":null,"abstract":"<p>Streams process and transport vast carbon quantities along the aquatic continuum. The balance between processing and downstream export is governed by metabolism, which in turn is regulated by distinct physicochemical controls that vary through space and time. However, macronutrient stoichiometry is rarely considered over absolute concentrations. Here, we examined physical, chemical, and stoichiometric controls on stream metabolism, organic carbon mineralization, and carbon spiraling over 2 years. Stream discharge, temperature, and light were the primary drivers across metabolic and carbon cycling parameters. In generalized additive models, physical variables accounted for up to four times more deviance than stoichiometry, with consistently more important associations in partial least squares regressions. Increased discharge and temperature promoted heterotrophy and strongly controlled metabolic balance, while dissolved C : P and C : N provided minor moderating effects. Our study highlights varied physical controls on stream metabolic processes and suggests nutrient concentrations and stoichiometry are secondary regulators, especially when C : N : P are non-limiting—an important reflection when evaluating future effects of nutrient pollution on the global carbon cycle.</p>","PeriodicalId":18143,"journal":{"name":"Limnology and Oceanography","volume":"71 10","pages":""},"PeriodicalIF":3.5,"publicationDate":"2026-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/lno.70519","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149086872","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"From net sink to episodic source: Seasonal dissolved inorganic carbon budget in an intertidal basin","authors":"Julia Meyer,&nbsp;Andrea Luebben,&nbsp;Helmuth Thomas,&nbsp;Yoana G. Voynova,&nbsp;Thomas H. Badewien,&nbsp;Bryce Van Dam","doi":"10.1002/lno.70514","DOIUrl":"10.1002/lno.70514","url":null,"abstract":"<p>The back-barrier basin of Spiekeroog in the East Frisian Wadden Sea is a biogeochemically dynamic intertidal system that plays a key role in regulating coastal carbon fluxes and regional dissolved inorganic carbon (DIC) budgets. Compared to total alkalinity, DIC fluxes in this region remain poorly quantified, limiting a comprehensive understanding of coastal carbon cycling. From October 2021 to December 2022, we combined discrete and in situ measurements, which allowed to model lateral DIC fluxes continuously and to investigate seasonal DIC sink/source dynamics. On average, based on 134 measurement days distributed across all seasons in 2022, the back-barrier Spiekeroog basin acted as a net DIC sink to the adjacent Wadden Sea, with a mean daily flux of 0.18 ± 1.48 mol m⁻² d⁻¹. Integrated over the area of the back-barrier basin, this corresponds to a total annual DIC uptake of 4.22 ± 1.85 Gmol yr⁻¹ in 2022. Summer also exhibited net DIC import, albeit at lower rates, reflecting ongoing photosynthetic activity. In contrast, autumn was characterized by episodic DIC export, linked to sediment–water exchange, remineralization, and physical drivers such as storm-induced mixing. Additionally, a seasonal carbon budget was established by integrating air–sea CO₂ exchange and submarine groundwater discharge (SGD) estimates from the literature. This highlighted significant internal retention and transformation of DIC within the system. Submarine groundwater discharge was identified as a major knowledge gap, underscoring the need for integrated high-resolution measurements and modeling to constrain regional DIC budgets and guide climate change mitigation strategies.</p>","PeriodicalId":18143,"journal":{"name":"Limnology and Oceanography","volume":"71 10","pages":""},"PeriodicalIF":3.5,"publicationDate":"2026-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/lno.70514","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149086099","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}