Limnology and Oceanography Letters最新文献

Contrasting associations of sea-ice meltwater and meteoric water with nitrogen uptake patterns in the summer Cosmonaut Sea, Antarctica 南极宇航员海夏季海冰融水和大气水与氮吸收模式的对比关系

IF 7.3 2区地球科学

Limnology and Oceanography Letters Pub Date : 2026-10-17 DOI: 10.1002/lol2.70188

Kun Zhang, Qianyao Ma, Jun Zhao, Qiang Hao, Shunan Cao, Zifei Yang, Zhen Tang, Minfang Zheng, Mengya Chen, Jianfeng He, Min Chen

{"title":"Contrasting associations of sea-ice meltwater and meteoric water with nitrogen uptake patterns in the summer Cosmonaut Sea, Antarctica","authors":"Kun Zhang, Qianyao Ma, Jun Zhao, Qiang Hao, Shunan Cao, Zifei Yang, Zhen Tang, Minfang Zheng, Mengya Chen, Jianfeng He, Min Chen","doi":"10.1002/lol2.70188","DOIUrl":"10.1002/lol2.70188","url":null,"abstract":"Nitrogen uptake by phytoplankton influences Southern Ocean productivity and carbon export, but how source-resolved meltwater is associated with nitrate and ammonium use remains unclear. Here, 15N tracer incubations and a δ18O-salinity mixing model were combined to examine nitrogen uptake in the early-summer Cosmonaut Sea. Depth-integrated nitrate (ρNO3) and ammonium uptake (ρNH4) rates averaged 8.0 and 1.3 mmol m−2 d−1, respectively, yielding a mean f-ratio of 0.80. Meteoric water (MW) fractions were positively correlated with chlorophyll a (Chl a) concentration, the micro-sized (> 20 μm) Chl a fraction, and ρNO3, suggesting that MW-influenced waters were associated with higher biomass, larger size structure, and enhanced nitrate uptake. Sea-ice meltwater fractions were positively correlated with ambient <math>\u0000 <semantics>\u0000 <mrow>\u0000 <msubsup>\u0000 <mi>NH</mi>\u0000 <mn>4</mn>\u0000 <mo>+</mo>\u0000 </msubsup>\u0000 </mrow>\u0000 <annotation>$$ {mathrm{NH}}_4^{+} $$</annotation>\u0000 </semantics></math> and ρNH4, consistent with greater regenerated nitrogen availability following sea-ice retreat and post-bloom recycling. These source-specific associations highlight the need to consider meltwater timing and source when assessing nitrogen assimilation pathways and biological-pump potential in Antarctic coastal waters.","PeriodicalId":18128,"journal":{"name":"Limnology and Oceanography Letters","volume":"11 6","pages":""},"PeriodicalIF":7.3,"publicationDate":"2026-10-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/lol2.70188","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149198892","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Microbial deamination of peptides and proteins as a source of persistent marine dissolved organic matter 作为持久性海洋溶解有机物来源的多肽和蛋白质的微生物脱胺作用

IF 7.3 2区地球科学

Limnology and Oceanography Letters Pub Date : 2026-10-15 DOI: 10.1002/lol2.70187

Pauline L. Martinot, Cédric G. Fichot, Hussain Abdulla, Karl Kaiser

{"title":"Microbial deamination of peptides and proteins as a source of persistent marine dissolved organic matter","authors":"Pauline L. Martinot, Cédric G. Fichot, Hussain Abdulla, Karl Kaiser","doi":"10.1002/lol2.70187","DOIUrl":"10.1002/lol2.70187","url":null,"abstract":"Refractory dissolved organic nitrogen is a major component of the ocean's nitrogen pool, yet the mechanisms producing and preserving it remain poorly understood. Here, we show that deaminated peptides (DAPs), derived from microbial processing of proteinaceous material, are ubiquitous across oxygenated marine environments—from productive coastal waters to the oligotrophic ocean—and persist from surface to bathypelagic depths. Using ultrahigh-resolution mass spectrometry and a curated peptide database, we detected candidate DAP formulas with substantial contributions from hydrophobic amino-acid residues and recurrent compositions containing diaminopimelic acid (Dapa), consistent with a contribution of bacterial cell-wall material. Laboratory incubations demonstrate substrate control on DAP composition: simple-substrate treatments yield narrow, source-specific amino acid profiles, whereas complex substrates produce broader assemblages resembling field observations. Together, widespread DAP occurrence and substrate-dependent production in microbial incubations support peptide deamination as a potential microbial nitrogen pump pathway, linking labile surface nitrogen to persistent storage in the ocean interior.","PeriodicalId":18128,"journal":{"name":"Limnology and Oceanography Letters","volume":"11 6","pages":""},"PeriodicalIF":7.3,"publicationDate":"2026-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/lol2.70187","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149172780","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Ultraviolet radiation lowers upper thermal limits in marine diatoms 紫外线辐射降低了海洋硅藻的热上限

IF 7.3 2区地球科学

Limnology and Oceanography Letters Pub Date : 2026-10-13 DOI: 10.1002/lol2.70185

Yuheng An, Zhenzhen Li, Futian Li, Juan Diego Gaitan-Espitia, Yaping Wu, Juntian Xu

{"title":"Ultraviolet radiation lowers upper thermal limits in marine diatoms","authors":"Yuheng An, Zhenzhen Li, Futian Li, Juan Diego Gaitan-Espitia, Yaping Wu, Juntian Xu","doi":"10.1002/lol2.70185","DOIUrl":"10.1002/lol2.70185","url":null,"abstract":"Escalating ultraviolet radiation (UVR) and ocean warming are expected to interactively shape phytoplankton performance, yet their combined effects on diatom thermal plasticity remain poorly resolved. We quantified how UVR alters growth-based thermal performance curves in three model marine diatoms grown across species-specific temperature gradients (5–28°C) under UV-excluded (PAR) and UV-present (PAB) solar radiation. UVR generally suppressed growth most strongly at thermal extremes and consistently lowered the critical thermal maximum (CTmax) in all three species, indicating reduced tolerance to high temperature. UVR also narrowed thermal breadth in two species and reduced thermal tolerance in two species, whereas effects on maximum growth rate (rmax), optimum temperature (Topt), and thermal safety margin (TSM) were species specific. These results indicate that UVR modifies growth-based thermal performance rather than acting solely as an additive stressor, bringing populations closer to their upper thermal limits under the tested conditions. Incorporating UVR-sensitive thermal traits into predictive frameworks may help constrain projections of phytoplankton productivity under warming and changing light climates.","PeriodicalId":18128,"journal":{"name":"Limnology and Oceanography Letters","volume":"11 6","pages":""},"PeriodicalIF":7.3,"publicationDate":"2026-10-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/lol2.70185","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149172875","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Hidden subsurface suspended sediment export from Greenland's marine-terminating glaciers 格陵兰岛海洋终止冰川的隐藏地下悬浮沉积物输出

IF 7.3 2区地球科学

Limnology and Oceanography Letters Pub Date : 2026-10-09 DOI: 10.1002/lol2.70186

Yaqing Ruan, Eric P. Achterberg, Hilde Oliver, Lukas L. Taenzer, Xin Huang, Camilla S. Andresen, Mark J. Hopwood

{"title":"Hidden subsurface suspended sediment export from Greenland's marine-terminating glaciers","authors":"Yaqing Ruan, Eric P. Achterberg, Hilde Oliver, Lukas L. Taenzer, Xin Huang, Camilla S. Andresen, Mark J. Hopwood","doi":"10.1002/lol2.70186","DOIUrl":"10.1002/lol2.70186","url":null,"abstract":"Runoff and calved ice volumes from the Greenland Ice Sheet are well constrained, but quantifying the associated suspended sediment flux remains challenging. Here we present near-terminus observations from three glacierized fjords in southeast Greenland, combining full-depth turbidity profiles and current velocity from summer 2024 to evaluate sediment export. We identify extensive subsurface sediment plumes from marine-terminating glaciers which are undetectable using remote sensing approaches and underrepresented in fjord sediment-core reconstructions. Sediment cores document an exponential increase in sediment accumulation rates from glacier-distal to glacier-proximal coring sites. Therefore, the scarcity of sediment cores collected in the immediate vicinity of glacier termini suggests that sediment export from marine-terminating glaciers has likely been systematically underestimated. Our findings underscore the importance of direct observations for quantifying sediment transport in glacierized fjords and suggest the Greenland Ice Sheet contributes more sediment to ocean margins than previously assumed.","PeriodicalId":18128,"journal":{"name":"Limnology and Oceanography Letters","volume":"11 6","pages":""},"PeriodicalIF":7.3,"publicationDate":"2026-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/lol2.70186","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149130612","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Seascape genomics reveals high genetic diversity and apparent panmixia in endemic Southern Ocean phytoplankton 海景基因组学揭示了南大洋特有浮游植物的高遗传多样性和明显的泛菌性

IF 7.3 2区地球科学

Limnology and Oceanography Letters Pub Date : 2026-10-05 DOI: 10.1002/lol2.70166

Ian W. Bishop, Tatiana A. Rynearson

{"title":"Seascape genomics reveals high genetic diversity and apparent panmixia in endemic Southern Ocean phytoplankton","authors":"Ian W. Bishop, Tatiana A. Rynearson","doi":"10.1002/lol2.70166","DOIUrl":"10.1002/lol2.70166","url":null,"abstract":"The adaptive potential and resilience of cold-adapted phytoplankton to climate change have the potential to impact polar marine food webs and global biogeochemical cycles. Two central but poorly constrained facets of adaptive potential in polar phytoplankton are standing genetic diversity and its spatial structure. Here, we partially sequenced 30 field isolate genomes of a commonly-occurring endemic Southern Ocean (SO) phytoplankton, the diatom Actinocyclus actinochilus, and analyzed patterns in standing genetic diversity and geographic structure. Across a > 4000 km high-latitude SO transect, A. actinochilus exhibited high genome-wide nucleotide diversity (π = 0.05) suggesting large effective population size. Divergence among genomes was low and did not resolve into genetically distinct populations, suggesting a panmictic population structure that we hypothesize is maintained by SO circumpolar currents driving high levels of zonal gene flow. Our findings have implications for SO phytoplankton resilience and highlight a plausible buffering mechanism for SO phytoplankton in response to rapid environmental change.","PeriodicalId":18128,"journal":{"name":"Limnology and Oceanography Letters","volume":"11 6","pages":""},"PeriodicalIF":7.3,"publicationDate":"2026-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/lol2.70166","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149087581","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Deep learning–assisted coral morphology cover across 742 sites on the Great Barrier Reef (2022–2025): A Great Reef Census citizen science dataset 深度学习辅助珊瑚形态覆盖大堡礁742个地点（2022-2025）：大堡礁普查公民科学数据集

IF 7.3 2区地球科学

Limnology and Oceanography Letters Pub Date : 2026-10-05 DOI: 10.1002/lol2.70168

Christopher L. Lawson, Kathryn M. Chartrand, Peter J. Mumby, Andy Ridley, Benjamin Vozzo, Seán Daly, Chandru Ganesan, Aruna Kolluru, Chris M. Roelfsema

{"title":"Deep learning–assisted coral morphology cover across 742 sites on the Great Barrier Reef (2022–2025): A Great Reef Census citizen science dataset","authors":"Christopher L. Lawson, Kathryn M. Chartrand, Peter J. Mumby, Andy Ridley, Benjamin Vozzo, Seán Daly, Chandru Ganesan, Aruna Kolluru, Chris M. Roelfsema","doi":"10.1002/lol2.70168","DOIUrl":"10.1002/lol2.70168","url":null,"abstract":"Citizen science can expand the spatial extent of coral reef surveys, but its value is often limited by inconsistent data quality and slow manual analysis. Here we combine volunteer-collected imagery with deep learning to overcome these constraints, delivering validated coral cover data at scale. We present 46,879 benthic seascape images from 742 sites across 267 reefs on the Great Barrier Reef, collected by Great Reef Census volunteers between September 2022 and February 2025. Images were analyzed using a deep learning segmentation model combined with online labelling by citizen scientists, yielding site-level percent cover for three key coral types: branching Acropora, plating Acropora, and massive-form corals. Data were validated with 99% accuracy against manual annotation, with 18–80 images per site yielding 95% accuracy. This geolocated dataset complements professional and government reef monitoring and is publicly available for research, conservation planning, and further tool development.","PeriodicalId":18128,"journal":{"name":"Limnology and Oceanography Letters","volume":"11 6","pages":""},"PeriodicalIF":7.3,"publicationDate":"2026-10-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/lol2.70168","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149087516","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Molecular evidence of domoic acid production in the high Arctic Qikiqtaaluk Region of Inuit Nunangat 努南加特因纽特人齐齐克塔卢克高北极地区软骨藻酸生产的分子证据

IF 7.3 2区地球科学

Limnology and Oceanography Letters Pub Date : 2026-09-30 DOI: 10.1002/lol2.70180

Patrick L. White, Gordon Lax, Margaret Mars Brisbin, Arianna I. Krinos, Harriet Alexander, Jenifer S. Spence, Maria A. Cavaco, Terry Noah, Megan E. Roberts, Simon Shyka-Brown, Marty Kuluguqtuq, Laisa Audlaluk-Watsko, Meeka Kiguktak, Stephanie Waterman, Andrew K. Hamilton, David Didier, Maya P. Bhatia, Erin M. Bertrand

{"title":"Molecular evidence of domoic acid production in the high Arctic Qikiqtaaluk Region of Inuit Nunangat","authors":"Patrick L. White, Gordon Lax, Margaret Mars Brisbin, Arianna I. Krinos, Harriet Alexander, Jenifer S. Spence, Maria A. Cavaco, Terry Noah, Megan E. Roberts, Simon Shyka-Brown, Marty Kuluguqtuq, Laisa Audlaluk-Watsko, Meeka Kiguktak, Stephanie Waterman, Andrew K. Hamilton, David Didier, Maya P. Bhatia, Erin M. Bertrand","doi":"10.1002/lol2.70180","DOIUrl":"https://doi.org/10.1002/lol2.70180","url":null,"abstract":"Domoic acid, a neurotoxin produced by the diatom Pseudo-nitzschia, is an increasing concern in Arctic marine environments. Shellfish harvesting occurs in many Canadian Arctic waterways in Inuit Nunangat and is the main vector for human domoic acid exposure, but most toxin monitoring has occurred in the Pacific Arctic region. This leaves a major knowledge gap across much of Inuit Nunangat. Here, through a collaboration between Southern researchers and the community of Ausuittuq (Grise Fiord), we investigated domoic acid production in Jones Sound, Qikiqtaaluk Region, Nunavut. Using transcriptomic biomarkers of domoic acid biosynthesis, we find evidence of toxin production by Pseudo-nitzschia in surface waters stimulated by glacier-driven nutrient inputs. The discovery of domoic acid production capacity—even by a relatively small Pseudo-nitzschia population—near the northernmost community in Canada demonstrates a need for new community-driven research and monitoring to understand the prevalence and drivers of domoic acid across Inuit Nunangat.","PeriodicalId":18128,"journal":{"name":"Limnology and Oceanography Letters","volume":"11 6","pages":""},"PeriodicalIF":7.3,"publicationDate":"2026-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/lol2.70180","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149072582","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Taxon-specific community structure partitions marine particle size spectra into stable and dynamic components 特定分类单元的群落结构将海洋粒径谱划分为稳定组分和动态组分

IF 7.3 2区地球科学

Limnology and Oceanography Letters Pub Date : 2026-09-30 DOI: 10.1002/lol2.70174

Fernanda Henderikx-Freitas, Andrew J. Hirzel, Angelicque E. White

{"title":"Taxon-specific community structure partitions marine particle size spectra into stable and dynamic components","authors":"Fernanda Henderikx-Freitas, Andrew J. Hirzel, Angelicque E. White","doi":"10.1002/lol2.70174","DOIUrl":"10.1002/lol2.70174","url":null,"abstract":"Oceanic particle size distributions (PSDs) link plankton community structure to biogeochemical cycling. Although the influence of community composition on size spectra is well recognized in theoretical approaches, long-term empirical evidence connecting taxon-specific variability to bulk PSD structure remains limited. Here, we use 9 yr of taxon-resolved PSDs spanning ~ 7–100 μm in the surface waters of the oligotrophic North Pacific to show that deviations from canonical scaling are structured, repeatable, and attributable to variability in specific taxa. We show that bulk PSDs reflect the superposition of a persistent baseline assemblage dominated by small spherical particles, dinoflagellates, and haptophytes, and a dynamic component driven by diatoms, colonial cyanobacteria, and detritus that restructure the size spectrum across seasons. By quantifying how taxon-specific variability propagates into bulk size metrics, this study provides new empirical constraints for interpreting PSD variability in oligotrophic systems and for linking community composition to particle size structure in modeling contexts.","PeriodicalId":18128,"journal":{"name":"Limnology and Oceanography Letters","volume":"11 6","pages":""},"PeriodicalIF":7.3,"publicationDate":"2026-09-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/lol2.70174","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149086097","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

National‐scale remotely sensed lake surface temperature in the contiguous United States 美国周边地区的国家尺度遥感湖泊表面温度

IF 7.8 2区地球科学

Limnology and Oceanography Letters Pub Date : 2026-09-17 DOI: 10.1002/lol2.70183

Michael F. Meyer, Timothy J. Stagnitta, Wilson B. Salls, Brendan F. Wakefield, Tyler V. King

引用次数: 0

The fate of methane in ponds: Drivers of production, storage, oxidation, and emissions 池塘中甲烷的命运：生产、储存、氧化和排放的驱动因素

IF 7.8 2区地球科学

Limnology and Oceanography Letters Pub Date : 2026-09-16 DOI: 10.1002/lol2.70182

Joseph S. Rabaey, Pascal Bodmer, Abigail Bar, Sophia Pushlar, Meredith A. Holgerson

{"title":"The fate of methane in ponds: Drivers of production, storage, oxidation, and emissions","authors":"Joseph S. Rabaey, Pascal Bodmer, Abigail Bar, Sophia Pushlar, Meredith A. Holgerson","doi":"10.1002/lol2.70182","DOIUrl":"https://doi.org/10.1002/lol2.70182","url":null,"abstract":"Ponds are disproportionately large contributors to global carbon cycling, with substantial but variable emissions of methane (CH 4 ) to the atmosphere relative to their global surface area. Efforts to upscale pond CH 4 emissions have focused on broad‐scale correlates of emissions, yet mechanisms underlying the variability in emissions remain poorly constrained. In this study, we quantified total CH 4 production in 15 ponds across New York State (USA) using a mass‐balance approach, and partitioned CH 4 production into its major pathways: storage, oxidation, and emissions. We found that total CH 4 production was strongly regulated by metrics of ecosystem productivity ( R 2 = 0.77), while CH 4 storage accumulation rates and emissions were both controlled by pond morphology, stratification, and sheltering. Oxidation greatly influenced emissions, but remained difficult to predict. By quantifying all CH 4 pathways, our study clarifies drivers of CH 4 production, transport, and ultimately emissions, which can improve the accuracy of upscaling efforts.","PeriodicalId":18128,"journal":{"name":"Limnology and Oceanography Letters","volume":"151 1","pages":""},"PeriodicalIF":7.8,"publicationDate":"2026-09-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148979654","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0