Limnology and Oceanography最新文献

{"title":"Ecological patterns of benthic foraminiferal communities driven by seasonal and spatial environmental gradients in an Arctic fjord","authors":"Corentin Guilhermic, Maria Pia Nardelli, Aurélia Mouret, Antonio Pusceddu, Agnès Baltzer, Hélène Howa","doi":"10.1002/lno.12691","DOIUrl":"https://doi.org/10.1002/lno.12691","url":null,"abstract":"Arctic fjords, being transitional areas between glacier‐covered land and the ocean, are characterized by strong environmental gradients. The seasonal melting of glaciers generates strong turbidity and primary production antagonist gradients, which can affect benthic habitats. Two sampling campaigns were carried out in Kongsfjorden (Svalbard, Arctic Ocean) in May and August 2021 to investigate seasonal changes in benthic foraminifera spatial distribution and ecosystem functioning along a longitudinal transect of 10 km from the Kronebreen tidewater glacier front. Concurrently, organic matter quantity and biochemical composition, sediment grain size, and physical parameters of the water masses were investigated as possible driving factors of benthic ecosystem responses. In a previous study, three statistically determined foraminiferal biozonations (glacier proximal, medial, and distal) were observed on the basis of their species content within the closest 10 km from the glacier front, presenting similar assemblages in both seasons. Our results indicate that foraminiferal distribution at the local scale is mainly driven by physical and geochemical gradients induced by melting waters and sediment discharges from the tidewater glacier occurring during summer. Due to the climate change, the melting season is expected to last longer and increasing global temperature will much probably accelerate the melting processes. Our findings strongly support the use of foraminifera as bioindicators to monitor the effects of ongoing climate change on the benthic ecosystems of Arctic fjords and, accessorily, as proxies for reconstructing glacier front positions in the recent past.","PeriodicalId":18143,"journal":{"name":"Limnology and Oceanography","volume":null,"pages":null},"PeriodicalIF":4.5,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142236293","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 trends in Subantarctic plankton δ13C and δ15N are driven by phytoplankton dynamics and nutrient preference","authors":"Luca Stirnimann, Thomas G. Bornman, Hans M. Verheye, Sarah E. Fawcett","doi":"10.1002/lno.12685","DOIUrl":"https://doi.org/10.1002/lno.12685","url":null,"abstract":"The carbon and nitrogen isotope ratios (δ<jats:sup>13</jats:sup>C and δ<jats:sup>15</jats:sup>N) of marine plankton record biogeochemical processes at the base of the food web. In the Southern Ocean, such data, predominantly from summer, have been used to infer surface CO<jats:sub>2</jats:sub> concentrations and the potential for biological carbon export. However, variability in plankton δ<jats:sup>13</jats:sup>C and δ<jats:sup>15</jats:sup>N remains poorly understood, with the lack of seasonal measurements from the Southern Ocean emerging as a particular limitation. Here, we investigate the δ<jats:sup>13</jats:sup>C and δ<jats:sup>15</jats:sup>N of suspended particulate matter (SPM) and zooplankton collected from the Subantarctic Ocean in winter, summer, and autumn. The low summertime δ<jats:sup>13</jats:sup>C<jats:sub>SPM</jats:sub> and δ<jats:sup>15</jats:sup>N<jats:sub>SPM</jats:sub> can be explained by strong diatom reliance on nitrate supplied during winter mixing. A subsequent increase in δ<jats:sup>13</jats:sup>C<jats:sub>SPM</jats:sub> and decrease in δ<jats:sup>15</jats:sup>N<jats:sub>SPM</jats:sub> by autumn is consistent with iron limitation in mid‐ to late‐summer favoring diatom succession by nano‐phytoplankton that consume mainly recycled ammonium. By winter, bacterial decomposition of biomass outpaces new biomass production, decreasing δ<jats:sup>13</jats:sup>C<jats:sub>SPM</jats:sub> and raising δ<jats:sup>15</jats:sup>N<jats:sub>SPM</jats:sub>. The δ<jats:sup>13</jats:sup>C and δ<jats:sup>15</jats:sup>N of contemporaneously sampled zooplankton generally reflect the variability in δ<jats:sup>13</jats:sup>C<jats:sub>SPM</jats:sub> and δ<jats:sup>15</jats:sup>N<jats:sub>SPM</jats:sub>, with one autumn mismatch suggesting that in situ SPM is not always the dominant zooplankton food source. Our study shows how nutrient dynamics and phytoplankton community composition shape the seasonality of the Subantarctic's isotopic baselines, emphasizing a key role for iron availability. This work has implications for isotope‐based food web studies, highlighting the need to consider seasonal variability in δ<jats:sup>13</jats:sup>C<jats:sub>SPM</jats:sub> and δ<jats:sup>15</jats:sup>N<jats:sub>SPM</jats:sub>, as well as the different turnover times of phytoplankton (i.e., SPM) vs. zooplankton biomass.","PeriodicalId":18143,"journal":{"name":"Limnology and Oceanography","volume":null,"pages":null},"PeriodicalIF":4.5,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142245416","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":"High‐frequency sampling captures variability in phytoplankton population‐specific periodicity, growth, and productivity","authors":"Annette M. Hynes, Jordan Winter, Chris T. Berthiaume, Eric Shimabukuro, Kelsy Cain, Angelicque White, E. Virginia Armbrust, François Ribalet","doi":"10.1002/lno.12683","DOIUrl":"https://doi.org/10.1002/lno.12683","url":null,"abstract":"The Hawaii Ocean Time‐series (HOT) at Station ALOHA (22.75°N, 158°W) in the North Pacific Subtropical Gyre (NPSG) serves as a critical vantage point for observing plankton biomass production and its ecological implications. However, the HOT program's near‐monthly sampling frequency does not capture shorter time scale variability in phytoplankton populations. To address this gap, we deployed the SeaFlow flow cytometer for continuous monitoring during HOT cruises from 2014 to 2021. This approach allowed us to examine variations in the surface abundance and cell carbon content of specific phytoplankton groups: the cyanobacteria <jats:italic>Prochlorococcus</jats:italic>, <jats:italic>Synechococcus</jats:italic>, and <jats:italic>Crocosphaera</jats:italic> as well as a range of small eukaryotic phytoplankton ( 5 <jats:italic>μ</jats:italic>m). Our data showed that daily to monthly variability in <jats:italic>Prochlorococcus</jats:italic> and <jats:italic>Synechococcus</jats:italic> abundance matches seasonal and interannual variability, while small eukaryotic phytoplankton and <jats:italic>Crocosphaera</jats:italic> showed the highest seasonal and interannual fluctuations. The study also found that eukaryotic phytoplankton and <jats:italic>Crocosphaera</jats:italic> had higher median cellular growth rates (0.076 and , respectively) compared to <jats:italic>Prochlorococcus</jats:italic> and <jats:italic>Synechococcus</jats:italic> (0.037 and , respectively). These variances in abundance and growth rates indicate that shifts in the community structure significantly impact primary productivity in the NPSG. Our results underscore the importance of daily to monthly phytoplankton dynamics in ecosystem function and carbon cycling.","PeriodicalId":18143,"journal":{"name":"Limnology and Oceanography","volume":null,"pages":null},"PeriodicalIF":4.5,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142236585","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":"Biogeochemical cycling of trace elements and nutrients in ferruginous waters: Constraints from a deep oligotrophic ancient lake","authors":"David J. Janssen, Adrianus Damanik, Nicolas Tournier, Julie Tolu, Lenny Winkel, Sri Yudawati Cahyarini, Hendrik Vogel","doi":"10.1002/lno.12687","DOIUrl":"https://doi.org/10.1002/lno.12687","url":null,"abstract":"Iron‐rich, ferruginous waters were the dominant geochemical regime for most of Earth's history. Modern ferruginous waters are found in stratified, sulfur‐poor lakes, and serve as crucial analogs for biogeochemical cycling throughout Earth's past. Here we present the first depth‐resolved data of physical structure, nutrients and trace elements from Lake Poso (Indonesia), a deep oligotrophic ancient lake. Lake Poso is ferruginous, with anoxia below ~ 90 m depth, placing it among the world's largest ferruginous lakes. Physical stratification is weaker than other tropical anoxic lakes, indicating sensitivity for paleoclimate reconstructions. Trace elements and nutrients are predominantly shaped by the oxic–anoxic transition. Manganese– and Fe oxyhydroxide–driven biogeochemical cycling occurs at distinct depth horizons, with Co and Ni controlled by Mn and showing shallow release in anoxic waters, while V, Cr, P, and As are controlled by Fe, with release in surface sediments and diffusive transport. Chromium is nonquantitatively removed in anoxic waters, in contrast to widespread assumptions in Cr‐based paleoreconstructions. Oxycline U and Se removal corresponds to a local N minimum, suggesting biological reduction and/or uptake. These first ferruginous water Se data also show removal in sediments, indicating sediment signals reflect multiple removal processes and informing Se‐based paleoreconstructions, while the absence of sediment U removal contrasts other anoxic basins. A comparison with other ferruginous lakes demonstrates how local influences drive deviations from expectations in other systems, and highlight common, generalizable ferruginous basin features. Therefore, these data will guide research in ferruginous settings across space and time, and improve paleoreconstructions from ferruginous sediment records.","PeriodicalId":18143,"journal":{"name":"Limnology and Oceanography","volume":null,"pages":null},"PeriodicalIF":4.5,"publicationDate":"2024-09-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142236587","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":"Issue Information & TOC","authors":"","doi":"10.1002/lno.12699","DOIUrl":"10.1002/lno.12699","url":null,"abstract":"","PeriodicalId":18143,"journal":{"name":"Limnology and Oceanography","volume":null,"pages":null},"PeriodicalIF":3.8,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/lno.12699","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142236593","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":"Issue Information & Masthead","authors":"","doi":"10.1002/lno.12697","DOIUrl":"10.1002/lno.12697","url":null,"abstract":"","PeriodicalId":18143,"journal":{"name":"Limnology and Oceanography","volume":null,"pages":null},"PeriodicalIF":3.8,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/lno.12697","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142236591","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":"Issue Information & Members","authors":"","doi":"10.1002/lno.12700","DOIUrl":"10.1002/lno.12700","url":null,"abstract":"","PeriodicalId":18143,"journal":{"name":"Limnology and Oceanography","volume":null,"pages":null},"PeriodicalIF":3.8,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/lno.12700","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142236592","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":"Issue Information & Copyright","authors":"","doi":"10.1002/lno.12698","DOIUrl":"10.1002/lno.12698","url":null,"abstract":"","PeriodicalId":18143,"journal":{"name":"Limnology and Oceanography","volume":null,"pages":null},"PeriodicalIF":3.8,"publicationDate":"2024-09-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/lno.12698","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142236590","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":"Aerobic anoxygenic phototrophic bacteria correlate with picophytoplankton across the Atlantic Ocean but show unique vertical bioenergetics","authors":"Carlota R. Gazulla, Michal Koblížek, Jesús M. Mercado, Josep M. Gasol, Olga Sánchez, Isabel Ferrera","doi":"10.1002/lno.12682","DOIUrl":"https://doi.org/10.1002/lno.12682","url":null,"abstract":"Aerobic anoxygenic phototrophic (AAP) bacteria are a common part of microbial communities in the sunlit ocean. They contain bacteriochlorophyll <jats:italic>a</jats:italic> (BChl <jats:italic>a</jats:italic>)‐based photosystems that harvest solar energy for their metabolism. Across different oceanic regions, AAP bacteria seem to be more abundant in eutrophic areas, associated with high chlorophyll concentrations. While most previous studies focused on surface samplings, there is limited information regarding their vertical distribution in euphotic zones of the major ocean basins. Here, we hypothesized that AAP bacteria will follow a similar structure to the chlorophyll depth profile across areas with different degrees of stratification. To test this hypothesis, we enumerated AAP cells and determined bulk water BChl <jats:italic>a</jats:italic> concentrations along the photic zone of a latitudinal transect in the South and Central Atlantic Ocean. Overall, the distribution of AAP bacteria was highly correlated to that of chlorophyll <jats:italic>a</jats:italic> and to the abundance of picophytoplankton across both vertical and horizontal gradients. Furthermore, estimated light energy captured across the water column showed that, while AAP bacteria share a common latitudinal pattern of light absorption with picophytoplankton, they display a unique vertical arrangement with highest photoheterotrophic activity in the top 50 m of the surface ocean.","PeriodicalId":18143,"journal":{"name":"Limnology and Oceanography","volume":null,"pages":null},"PeriodicalIF":4.5,"publicationDate":"2024-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142233349","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":"Sediment dynamics shape macrofauna mobility traits and abundance on tidal flats","authors":"Zhengquan Zhou,&nbsp;Tim J. Grandjean,&nbsp;Jaco de Smit,&nbsp;Jim van Belzen,&nbsp;Gregory S. Fivash,&nbsp;Brenda Walles,&nbsp;Olivier Beauchard,&nbsp;Jeroen van Dalen,&nbsp;Daniel B. Blok,&nbsp;Lennart van IJzerloo,&nbsp;Tom Ysebaert,&nbsp;Tjeerd J. Bouma","doi":"10.1002/lno.12669","DOIUrl":"10.1002/lno.12669","url":null,"abstract":"<p>Tidal flats are valuable ecosystems that depend on complex biogeomorphic processes between organisms and sediment transport. Climate change has led to a rise in extreme weather events, such as storms. This, in turn, has increased sediment dynamics and created risks for the benthic communities inhabiting tidal flats. However, replicating sediment disturbances caused by extreme weather is difficult. To overcome this, we used the plow rake to enhance the natural tidal currents and wave conditions to simulate intensified sediment dynamics. The raking disturbance was repeated on two intertidal zones with different inundation frequencies and wind fetch levels to simulate the increasing frequency of storm impact on sediments due to climate change. We compared the measurements of sediment dynamics and macrofauna between plots that were raked and the control plots that were only influenced by natural hydrodynamics. Results showed that tidal flat sediments experienced erosion by 10–20 mm after six times biweekly raking treatments, depending on the site-specific hydrodynamic conditions. Sediment dynamics served as a helpful tool for monitoring the species distribution regarding mobility traits: the high dynamic exposed sites were inhabited by mobile species, while the low dynamic sheltered sites were characterized by less-mobile species. Moreover, the raking treatment decreased the abundance of species with immobile traits, yet the species composition did not experience significant change. Overall, the present findings indicate that tidal flats with low sediment dynamics and immobile macrofauna are at higher risk of declining abundance under intensified sediment disturbances than areas with high sediment dynamics and mobile macrofauna.</p>","PeriodicalId":18143,"journal":{"name":"Limnology and Oceanography","volume":null,"pages":null},"PeriodicalIF":3.8,"publicationDate":"2024-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/lno.12669","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142160604","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}