Limnology and Oceanography最新文献

{"title":"Elevated carbon dioxide enhances polyunsaturated fatty acids in Isochrysis galbana and improves rotifer growth through algal feeding","authors":"Yitong Wang, Xi Zhu, Yuna Wang, Xingxing Cai, Hao Long, Aiyou Huang, Yanhua Zeng, Wei Ren, Zhenyu Xie, Xiaoni Cai","doi":"10.1002/lno.70195","DOIUrl":"https://doi.org/10.1002/lno.70195","url":null,"abstract":"Elevated atmospheric CO<jats:sub>2</jats:sub> levels directly affect marine primary producers by altering their photosynthetic efficiency and biochemical composition, thereby modifying nutrient transfer throughout marine food webs. This study examines the physiological, biochemical, and transcriptomic responses of the microalga <jats:italic>Isochrysis galbana</jats:italic> when cultured under elevated CO<jats:sub>2</jats:sub> level (1000 <jats:italic>μ</jats:italic>atm CO<jats:sub>2</jats:sub>) and current ambient CO<jats:sub>2</jats:sub> level (420 <jats:italic>μ</jats:italic>atm CO<jats:sub>2</jats:sub>) conditions, as well as the subsequent effects of feeding these algae to rotifer (<jats:italic>Brachionus plicatilis</jats:italic>). Under high CO<jats:sub>2</jats:sub> conditions, <jats:italic>I. galbana</jats:italic> exhibited enhanced photosynthetic efficiency, carbon fixation, and energy metabolism, driven by the upregulation of genes involved in photosynthesis, the Calvin‐Benson cycle, and glycolysis. These molecular adaptations increased the growth rate by 24% and increased the content of polyunsaturated fatty acids (PUFAs) by 8%, including docosahexaenoic acid, which improves the nutritional quality of the alga. Feeding experiments demonstrated that rotifers fed with <jats:italic>I. galbana</jats:italic> grown under high‐CO<jats:sub>2</jats:sub> conditions exhibited improved growth and enriched PUFA profiles, highlighting the potential for high‐CO<jats:sub>2</jats:sub>‐induced changes in primary producers to enhance trophic transfer efficiency. This study provides new insights into the molecular mechanisms underlying <jats:italic>I. galbana</jats:italic>'s response to elevated CO<jats:sub>2</jats:sub> and its ecological implications. The findings emphasize the capacity of marine microalgae to adapt to environmental changes and highlight the cascading effects of elevated CO<jats:sub>2</jats:sub> on marine food web nutrition and dynamics.","PeriodicalId":18143,"journal":{"name":"Limnology and Oceanography","volume":"1 1","pages":""},"PeriodicalIF":4.5,"publicationDate":"2025-09-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145003167","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":"Sources of marine carbonyl sulfide and its precursors traced by sulfur isotopes","authors":"Chen Davidson, Alon Angert, Yasmin Avidani, Sinikka T. Lennartz, Marc von Hobe, Alon Amrani","doi":"10.1002/lno.70196","DOIUrl":"https://doi.org/10.1002/lno.70196","url":null,"abstract":"Carbonyl sulfide (OCS) is a major precursor of stratospheric sulfate aerosols and a proxy for terrestrial photosynthesis. In recent years, sulfur‐isotope measurements (δ<jats:sup>34</jats:sup>S) of OCS emerged as an approach to constrain the OCS budget. Yet, such measurements are still scarce for aquatic OCS. Here we present a large dataset of δ<jats:sup>34</jats:sup>S values of marine OCS. In addition, we present δ<jats:sup>34</jats:sup>S values of marine carbon disulfide (CS<jats:sub>2</jats:sub>) and dimethyl sulfide (DMS), which in the air, act as important precursors of tropospheric OCS. Samples were collected at the Atlantic Ocean, the Red Sea, the Mediterranean Sea, the Wadden Sea, and the North Sea. The gases were sampled by a water–air equilibrator, preserved in canisters, and analyzed via a preconcentration system coupled to a gas chromatograph connected to a multi‐collector inductively coupled plasma mass spectrometer. We found δ<jats:sup>34</jats:sup>S values of −3.8‰ to 19.4‰ for OCS, −10.5‰ to 20‰ for CS<jats:sub>2</jats:sub>, and 14–23‰ for DMS. These δ<jats:sup>34</jats:sup>S values are controlled mainly by two endmembers: production in the water column and production in sediments. Lab experiments suggest that the <jats:sup>34</jats:sup>S‐fractionation of OCS photo‐production is 0.8‰ ± 0.5‰. In addition, based on measurements from the Atlantic Ocean, we calculated the <jats:sup>34</jats:sup>S‐fractionation of OCS dark‐production as −6‰ ± 2‰. This new data significantly improves our knowledge of the sulfur isotope distribution of marine OCS and helps identify its different sources, sinks, and production pathways.","PeriodicalId":18143,"journal":{"name":"Limnology and Oceanography","volume":"16 1","pages":""},"PeriodicalIF":4.5,"publicationDate":"2025-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145003144","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":"Seasonal variation in bay‐marsh sediment exchange through a back‐barrier salt marsh tidal creek","authors":"Gregg A. Snedden, S. Jarrell Smith","doi":"10.1002/lno.70193","DOIUrl":"https://doi.org/10.1002/lno.70193","url":null,"abstract":"Salt marsh resilience to sea‐level rise largely depends on the balance of sediment exchanges with surrounding bays. In this study, we investigate mechanisms that determine residual sediment fluxes using continuous measurements of bay‐marsh sediment exchange conducted in a tidal creek spanning 13 months (753 tidal cycles) in an intertidal marsh recently subsidized with sediment via thin‐layer placement. The maximum water level in each tidal cycle varied over seasonal and fortnightly timescales and was driven by a combination of the seasonal cycle in mean sea level (maximum in September, minimum in January) and the fortnightly spring‐neap cycle. Residual water fluxes tended to be ebb‐directed during overbank tides, possibly due to water crossing creekshed boundaries in the intertidal zone when water levels were sufficiently high. Sediment concentrations on the ebb of overbank tides exceeded those of their corresponding floods, but only for tidal cycles in which water temperatures exceeded 14°C. The interaction of these dynamics resulted in over 90% of the net sediment export from the creek occurring during overbank tides during warmer months—conditions met in 30% of the observed tidal cycles. These findings exemplify the importance of accounting for seasonality in sediment fluxes when assessing sediment budgets of salt marshes and illustrate how sediment budgets assessed with shorter duration datasets may exhibit seasonal bias. Additionally, they suggest that sediment retention for thin‐layer sediment placement projects may be high over the course of the first year after sediment subsidies are deployed.","PeriodicalId":18143,"journal":{"name":"Limnology and Oceanography","volume":"53 1","pages":""},"PeriodicalIF":4.5,"publicationDate":"2025-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145003170","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":"Contact‐dependent iron uptake from dust revealed by elemental analysis of single Trichodesmium colonies","authors":"Yeala Shaked, Futing Zhang, Antonio Colussi, Ana Esther Mijovilovich, Meri Eichner, Siyuan Wang, Coco Koedooder, Ondrej Prasil, Syed Nadeem Hussain Bokhari, Hendrik Küpper","doi":"10.1002/lno.70194","DOIUrl":"https://doi.org/10.1002/lno.70194","url":null,"abstract":"Aerosol dust deposited on the nutrient‐deprived surface ocean can boost phytoplankton growth and oceanic carbon uptake. Low mineral solubility restricts the biological utilization of dust‐nutrients, thereby benefiting phytoplankton that actively dissolve dust. The ubiquitous colony‐forming, N<jats:sub>2</jats:sub>‐fixing cyanobacteria <jats:italic>Trichodesmium</jats:italic> specialize in dust‐nutrient utilization, with several dust‐dissolution pathways identified in natural populations. Studying active dust dissolution by <jats:italic>Trichodesmium</jats:italic>, we surveyed the elemental composition (i.e., quotas) of natural colonies from the dust‐impacted Red Sea using a benchtop micro‐x‐ray fluorescence imager. We also examined changes in the colonies' quotas during incubations with dust and nutrients. Accounting for inter‐colony variability, we analyzed 106 individual colonies. Since particles often appeared on the surface of colonies, we carefully analyzed all images, removing dust particle signals from colony quotas. Focusing on the colonies' iron (Fe) and phosphorus (P) quotas, we observed contrasting patterns of inter‐colony variability and responses to dust, likely reflecting distinct nutrient sources—Fe sourced from dust and P sourced from the dissolved phase. Iron uptake from dust was repeatedly observed, but only upon colony–mineral interactions, indicative of contact‐dependent active dissolution. The role of dust in Fe nutrition was also evident from the minor impact of dissolved Fe complexation on Fe quotas. Phosphorus quotas responded rapidly to P addition or removal, but not to dust. Natural colonies collected over a season had heterogeneous Fe quotas but homogeneous P quotas, further supporting their distinct sources. Predictions of <jats:italic>Trichodesmium</jats:italic>'s bloom dynamics in particle‐rich and dust‐impacted ocean environments should incorporate its ability to dissolve Fe‐minerals.","PeriodicalId":18143,"journal":{"name":"Limnology and Oceanography","volume":"20 1","pages":""},"PeriodicalIF":4.5,"publicationDate":"2025-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145003172","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":"Climate change impacts to upwelling and shallow reef nutrient sources across an oceanic archipelago","authors":"Danielle L. Spring, Michael D. Fox, J. A. Mattias Green, Robin Guillaume‐Castel, Zoe Jacobs, Ronan C. Roche, John R. Turner, Gareth J. Williams","doi":"10.1002/lno.70172","DOIUrl":"https://doi.org/10.1002/lno.70172","url":null,"abstract":"Upwelling delivers key nutritional and energetic subsidies to coral reef communities that affect the growth, abundance, and ecology of organisms across trophic levels. However, the cross‐scale oceanographic and atmospheric drivers of localized upwelling on many reefs remain unresolved, limiting our ability to predict how climate change might disrupt upwelling patterns and impact reef communities across geographies. Using high temporal resolution (10 second) in situ temperature measurements collected over 18 months that encompassed the strongest positive Indian Ocean Dipole phase of this century, we demonstrate a highly nonlinear effect of climate‐driven mixed layer depth on upwelling intensity across the latitudinal range of the Chagos Archipelago (~ 200 km). The exposure of shallow (10–25 m depth) reef communities to deeper upwelled waters was maximized when the mixed layer depth was shallower than ~ 40 m, but virtually absent when the mixed layer depth was deeper than ~ 60 m. By combining these temperature data with nitrogen stable isotopes (δ<jats:sup>15</jats:sup>N) from a common macroalga, we show these variations in upwelling correlate with altered nutrient sources that have direct measurable impacts on reef organisms across the Archipelago. We further show that over the past 40 years, positive phases of the Indian Ocean Dipole correlate with an anomalously deep surface mixed layer on these reefs, each time likely restricting upwelling. Given these extreme events are increasing in frequency under climate change, this poses the possibility of a markedly different upwelling regime across the Archipelago over the coming century, with currently unknown ecological consequences.","PeriodicalId":18143,"journal":{"name":"Limnology and Oceanography","volume":"16 1","pages":""},"PeriodicalIF":4.5,"publicationDate":"2025-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145003171","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":"A large, infrequent ecosystem subsidy (cicada carcasses) and warming additively accelerate development and increase growth of larval amphibians","authors":"Elizabeth N. Gallagher, María J. González, Alexis D. Perminter, Michael J. Vanni","doi":"10.1002/lno.70191","DOIUrl":"https://doi.org/10.1002/lno.70191","url":null,"abstract":"Many ecosystems receive resource subsidies that affect productivity and food webs. Ecosystem subsidies vary in quantity, quality, and timing, and effects are often mediated by environmental factors, including temperature. Deposition of periodical cicada carcasses into ponds represents a large, high‐quality, infrequent subsidy. Cicadas emerge in massive numbers every 17 yr, and many individuals die and fall into aquatic ecosystems. As climate warms, future cicada subsidies may enter warmer ponds. We conducted a mesocosm experiment with a factorial design to examine the effects of cicada carcasses and elevated (~ 2.6°C) temperature on the growth and development of tadpoles of a common frog, <jats:italic>Hyla chrysoscelis</jats:italic>. Carcasses and warming each increased frog size at metamorphosis and shortened the time to metamorphosis, and the effects of cicadas and warming were additive for both traits. Mass at metamorphosis was largest and time to metamorphosis shortest with carcass addition and warmed temperature, whereas mass at metamorphosis was smallest and time to metamorphosis longest under ambient temperature without carcasses. Carcasses greatly increased algae biomass (periphyton and phytoplankton), possibly accounting for faster development and larger size of frogs. Warming did not increase standing algal biomass, but increased primary production, possibly increasing food supply for, and growth rates of, tadpoles. Our results show that a large, high‐quality, infrequent subsidy strongly affects pond amphibians, and effects are additively enhanced by warming. Because adult frogs migrate to land, live for several years, and return to their natal pond to breed, a cicada carcass subsidy may mediate reciprocal resource fluxes between land and ponds for several years.","PeriodicalId":18143,"journal":{"name":"Limnology and Oceanography","volume":"16 1","pages":""},"PeriodicalIF":4.5,"publicationDate":"2025-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144930627","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":"Bacteriochlorophyll reveals estuarine hypoxia and anoxygenic photosynthetic carbon fixation","authors":"Jiawei Kan, Liqin Duan, Jinming Song, Meiling Yin, Xuegang Li, Xiaoqi Liu, Huamao Yuan, Yingxia Wang","doi":"10.1002/lno.70203","DOIUrl":"https://doi.org/10.1002/lno.70203","url":null,"abstract":"Bacteriochlorophylls (Bchls) are photosynthetic pigments produced by aerobic anoxygenic photosynthetic bacteria and anoxygenic photosynthetic bacteria. However, the sources, degradation, and influence of redox conditions in marine environments remain unclear. This study investigated the distribution of Bchls in the Changjiang Estuary to evaluate their origins, degradation, and environmental response. Results showed that total bacteriochlorophylls <jats:italic>a</jats:italic> (T<jats:sub>Bchl<jats:italic>a</jats:italic></jats:sub>), including bacteriochlorophyll <jats:italic>a</jats:italic> (Bchl <jats:italic>a</jats:italic>) and its degradation product bacteriopheophytin <jats:italic>a</jats:italic> (Bphe <jats:italic>a</jats:italic>), were higher in surface waters than in bottom waters in the inner estuary, where microbial evidence (<jats:italic>Sphingomonadaceae</jats:italic>) identified aerobic anoxygenic photosynthetic bacteria as the dominant source of T<jats:sub>Bchl<jats:italic>a</jats:italic></jats:sub>. In contrast, the outer estuary exhibited elevated T<jats:sub>Bchl<jats:italic>a</jats:italic></jats:sub> in bottom waters, with purple sulfur bacteria (<jats:italic>Chromatiaceae</jats:italic> and <jats:italic>Ectothiorhodospiraceae</jats:italic>) as the primary contributors. Significant negative correlations between Bphe <jats:italic>a</jats:italic> concentrations in bottom seawaters and surface sediments and the dissolved oxygen levels in bottom waters, along with a positive correlation between Bphe <jats:italic>a</jats:italic> in the surface sediments and the salinity difference between bottom and surface seawaters (Δ<jats:italic>S</jats:italic>), suggest that Bphe <jats:italic>a</jats:italic> may serve as a useful indicator of hypoxia and water stratification. The contribution of anoxygenic photosynthetic bacteria to carbon fixation is expected to increase notably, potentially reaching 16% of phytoplankton carbon fixation after 100 years under expanding hypoxia. These findings establish Bchls as reliable indicators of hypoxia and water stratification and provide a framework for reevaluating carbon fixation in global hypoxic coastal systems.","PeriodicalId":18143,"journal":{"name":"Limnology and Oceanography","volume":"274 1","pages":""},"PeriodicalIF":4.5,"publicationDate":"2025-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144930628","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":"Net emission of atmospheric volatile organic compounds from ponds in a peatland forest","authors":"Yinghuan Qin, Kajsa Emilia Roslund, Amy Samantha Smart, Jesper Riis Christiansen, Riikka Rinnan","doi":"10.1002/lno.70202","DOIUrl":"https://doi.org/10.1002/lno.70202","url":null,"abstract":"The role of small water bodies in global carbon emissions is increasingly acknowledged. In addition to the well‐investigated greenhouse gases, carbon dioxide (CO<jats:sub>2</jats:sub>) and methane, volatile organic compounds (VOCs) may be emitted from freshwater ecosystems, especially from small water bodies, but the composition of emitted VOCs and emission magnitudes remain largely undescribed. Referring to empirical great contributors of freshwater greenhouse gases, we assessed seasonal VOC emissions from three carbon and nutrient‐rich ponds in a peatland forest in Denmark. These ponds were CO<jats:sub>2</jats:sub> emitters throughout the sampling period (19.5 ± 67.7 to 396.8 ± 120.0 mg m<jats:sup>−2</jats:sup> h<jats:sup>−1</jats:sup>). The total net fluxes of &gt; C5 VOCs measured in situ ranged from 7.8 ± 1.4 to 95.3 ± 4.5 <jats:italic>μ</jats:italic>g m<jats:sup>−2</jats:sup> h<jats:sup>−1</jats:sup> and over one hundred compounds were detected. The emissions consisted mainly of hydrocarbons, oxygenated VOCs, and terpenoids (isoprene, monoterpenoids, and sesquiterpenoids). We found the in situ VOC fluxes and compositions varied with season and were positively correlated with chamber temperature. These fluxes also differed between ponds and were related to the chemical properties of pond water. Additionally, we observed emissions of significant and various lighter VOCs (&lt; C5) and sulfur/nitrogen‐containing compounds in complementary lab measurements and demonstrated again the temperature dependence and pond‐to‐pond heterogeneity of VOC emissions. Overall, our findings indicate natural eutrophic ponds are net VOC sources. The significance of these emissions for carbon budgets and atmospheric impact requires future research.","PeriodicalId":18143,"journal":{"name":"Limnology and Oceanography","volume":"63 1","pages":""},"PeriodicalIF":4.5,"publicationDate":"2025-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144930629","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":"Carbon dioxide emissions across contrasting urban freshwater ecosystems","authors":"Clara Romero González‐Quijano, Sonia Herrero Ortega, Ruben del Campo, Peter Casper, Tobias Goldhammer, Mark O. Gessner, Gabriel A. Singer","doi":"10.1002/lno.70165","DOIUrl":"https://doi.org/10.1002/lno.70165","url":null,"abstract":"Carbon dioxide (CO<jats:sub>2</jats:sub>) emissions from freshwaters represent a globally important carbon flux. However, CO<jats:sub>2</jats:sub> fluxes from urban waters remain poorly constrained, and challenges remain for reliable upscaling, partly because of the high diversity of urban aquatic ecosystems. Using floating chambers to measure fluxes instantaneously and monitor them over multiple days, we estimated CO<jats:sub>2</jats:sub> emissions at 31 sites (lakes, ponds, rivers and streams) across the city of Berlin in four seasons. We evaluated land cover, nutrient concentrations, dissolved organic matter (DOM) composition, and chlorophyll‐<jats:italic>a</jats:italic> and micropollutant concentrations as potential drivers of CO<jats:sub>2</jats:sub> emissions. CO<jats:sub>2</jats:sub> fluxes from lakes and ponds averaged 0.41 g C m<jats:sup>−2</jats:sup>d<jats:sup>−1</jats:sup> (ranging from −0.45 to 3.38 across sites and methods), aligning with the results of previous studies. CO<jats:sub>2</jats:sub> fluxes from our urban rivers and streams averaging 0.78 g C m<jats:sup>−2</jats:sup>d<jats:sup>−1</jats:sup> (range from −0.13 to 7.32) were lower than typically reported for running waters, conceivably due to limited gas exchange in the channelized lowland systems. CO<jats:sub>2</jats:sub> fluxes were positively associated with DOM aromaticity, pointing to allochthonous inputs delivering resources for respiration, whether from (treated) wastewater or sealed urban surfaces. Fluxes were lower and more variable in settings favoring primary production, suggesting an impact of CO<jats:sub>2</jats:sub> drawdown. This condition coincided with a higher percentage of paved area. Extrapolation to the entire aquatic network of the city yielded an annual emission estimate of 8.8 Gg C‐CO<jats:sub>2</jats:sub>. An implication of this study is that urban lakes, ponds, rivers, and streams should be recognized as distinct systems when establishing large‐scale CO<jats:sub>2</jats:sub> emission budgets.","PeriodicalId":18143,"journal":{"name":"Limnology and Oceanography","volume":"28 1","pages":""},"PeriodicalIF":4.5,"publicationDate":"2025-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144930631","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":"Carbon sedimentation in shallow floodplain lakes","authors":"Belén Franco‐Cisterna, Laurence Carvalho, Iain Cross, Sarian Kosten, Teresa Needham, Chris Pointer, Sonia Yáñez, Suzanne McGowan","doi":"10.1002/lno.70199","DOIUrl":"https://doi.org/10.1002/lno.70199","url":null,"abstract":"Shallow lakes are increasingly recognized as important sites for organic carbon (OC) storage. However, the drivers of OC deposition in shallow floodplain lakes remain unclear due to complex terrestrial and aquatic interactions. Using 8 yr of monthly sediment trap data in a cross‐ecosystem experiment on six UK shallow lakes of varying riverine connectivity, we investigated the role of allochthonous (fluvial materials) vs. autochthonous (phytoplankton production) deposits as the OC supply to lake sediments. Organic carbon sedimentation rates in river‐connected (1.3 ± 1.2 g C m<jats:sup>−2</jats:sup> d<jats:sup>−1</jats:sup>, mean ± SD) and isolated lakes (0.5 ± 0.4 g C m<jats:sup>−2</jats:sup> d<jats:sup>−1</jats:sup>) surpassed those previously published for temperate zone eutrophic lakes. Generalized linear mixed‐effect models identified water column chlorophyll <jats:italic>a</jats:italic> as the best predictor of OC sedimentation for most lakes, suggesting that autochthonous phytoplankton production was the dominant driver of OC sedimentation, albeit stimulated by riverine nutrient supply. Carbon (C) transfer to the sediments was modulated by flow; during major floods, phytoplankton was likely flushed out of lakes, reducing OC sedimentation. Inorganic carbon sedimentation intermittently contributes substantially to carbon deposition in spring, summer, and winter. This study evidenced that shallow floodplain lakes are important sites for C deposition, with maximum C transfer to the sediments during the growing season. Future increases in hydrological variability could negatively impact the capacity of shallow floodplain lakes to retain and sequester carbon.","PeriodicalId":18143,"journal":{"name":"Limnology and Oceanography","volume":"27 1","pages":""},"PeriodicalIF":4.5,"publicationDate":"2025-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144919571","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}