Limnology and Oceanography最新文献

{"title":"Spatial and temporal patterns of bottom water euxinia in shallow areas of the southwestern Baltic Sea","authors":"Timo Spiegel,&nbsp;Matthias Thiele,&nbsp;Mark Schmidt,&nbsp;Ulrike Löptien,&nbsp;Heiner Dietze,&nbsp;René Friedland,&nbsp;Hermann W. Bange,&nbsp;Sarima Vahrenkamp,&nbsp;Mirjam Perner,&nbsp;Florian Scholz","doi":"10.1002/lno.70492","DOIUrl":"10.1002/lno.70492","url":null,"abstract":"<p>Sediments in productive coastal regions are hotspots of hydrogen sulfide (H₂S) production through microbial sulfate reduction. Under anoxic seafloor conditions, H₂S can escape the sediment and accumulate in bottom waters, where elevated concentrations render the benthic environment toxic, posing ecological and economic risks. The central Kiel Bight in the southwestern Baltic Sea shows a strong seasonal water column stratification, with hypoxic to anoxic bottom waters in late summer. Euxinic conditions (H₂S &gt; 1 <i>μ</i>M) have been observed locally, but their extent and underlying controls are not fully understood. This study investigates spatial and temporal patterns of bottom water H₂S in the central Kiel Bight using multi-annual sediment and water column measurements combined with machine learning models. We find that euxinia affects ~ 27% of the 622 km² seafloor in late summer, with recurring H₂S detections over the past decade highlighting its frequent occurrence. Sedimentary H₂S production is enhanced in areas with high organic matter delivery, yet H₂S production alone does not control its accumulation in bottom waters. Instead, the highest H₂S levels are observed in channels and basins where long deep-water residence times deplete oxidants, thereby facilitating H₂S accumulation. Furthermore, our findings demonstrate that effective H₂S monitoring requires sampling directly above the seafloor, such as collecting the supernatant water from sediment cores, because H₂S is often restricted to the lowermost water layer undetected by conventional water column profiling. Adapted monitoring is crucial to predict future development of euxinia in the shallow Baltic Sea and other coastal environments.</p>","PeriodicalId":18143,"journal":{"name":"Limnology and Oceanography","volume":"71 9","pages":""},"PeriodicalIF":3.5,"publicationDate":"2026-09-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/lno.70492","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148902401","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":"Beyond rhodoliths: Community-level carbon metabolism and calcification in coralline algal beds","authors":"Nadine Schubert,&nbsp;Fernando Tuya,&nbsp;Eduardo O. Bastos,&nbsp;Néstor E. Bosch,&nbsp;Paulo A. Horta,&nbsp;Julia Loring,&nbsp;André F. B. Macedo,&nbsp;Pedro Neves,&nbsp;Francisco Otero-Ferrer,&nbsp;Viviana Peña,&nbsp;Cláudia Ribeiro,&nbsp;Rui Santos,&nbsp;Marina N. Sissini,&nbsp;Enrique Tejero-Caballo,&nbsp;Tainá L. Gaspar,&nbsp;João Silva","doi":"10.1002/lno.70491","DOIUrl":"10.1002/lno.70491","url":null,"abstract":"<p>Coastal ecosystems play a major role in global carbon cycling and storage, yet the contribution of calcifying macroalgal habitats, such as coralline algal beds (CABs; rhodolith and maerl beds), remains poorly understood. Because carbon cycling in CABs is governed by community productivity and calcification, which exert opposing effects on seawater carbonate chemistry, understanding the balance between these processes is essential for determining whether CABs function as net carbon sinks or sources. Yet, community-level measurements remain scarce, and the environmental and biological drivers of CAB carbon balance are largely unknown. Here, we quantified net community productivity (NCP), net community calcification (NCC), and the resulting net carbon balance (NCP : NCC) in shallow warm-temperate and subtropical Atlantic CABs with contrasting rhodolith-associated communities, using in situ benthic chamber incubations. All CABs were net autotrophic, with NCP : NCC ratios ≥ 0.6, indicating that they acted as potentially carbon neutral and net carbon sinks. By combining our measurements with available community-level datasets, we identified light availability as the primary environmental driver of community productivity and calcification, whereas benthic community structure influenced the balance between these processes. Together, our findings demonstrate that CAB carbon balance is governed by the interaction between environmental conditions and community structure, providing the first mechanistic insight into the drivers of ecosystem carbon balance. This pronounced context dependency highlights the need for community-level assessments across broader environmental and biological settings to test the generality of these relationships and determine under which conditions carbon burial in CABs translates into a net contribution to coastal carbon storage.</p>","PeriodicalId":18143,"journal":{"name":"Limnology and Oceanography","volume":"71 9","pages":""},"PeriodicalIF":3.5,"publicationDate":"2026-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148895194","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":"Marine heatwaves reorganize phytoplankton bloom phenology in the Gulf of Alaska","authors":"Hisatomo Waga,&nbsp;Hiromichi Ueno,&nbsp;Thomas B. Kelly,&nbsp;Curry J. Cunningham,&nbsp;Sarah M. Hendricks","doi":"10.1002/lno.70487","DOIUrl":"10.1002/lno.70487","url":null,"abstract":"<p>Phytoplankton blooms structure primary production and food-web dynamics in the Gulf of Alaska, yet their response to recent warming and marine heatwaves (MHWs) remains poorly described. Using a parametric Gaussian framework applied to 21 years of satellite chlorophyll <i>a</i> (Chl <i>a</i>), this study classified daily Chl <i>a</i> timeseries into double-bloom, single spring-bloom, single fall-bloom, and no-bloom regimes and related these to large-scale oceanographic and atmospheric forcing. Double blooms with distinct spring and fall peaks dominated much of the domain in cold, dynamically active years characterized by negative sea surface temperature anomalies, depressed sea level, strong cross-shelf pressure gradients, and more frequent storms associated with an intensified Aleutian Low. In contrast, warm years with elevated sea level and weaker cross-shelf and atmospheric forcing favored single spring blooms and, in some areas, no-bloom conditions, while single fall blooms occurred under intermediate physical states. Although no significant linear trends in the areal extent occupied by each regime were detected over 2003–2023, years influenced by major MHWs projected strongly onto the warm, weakly forced end of this physical gradient and were associated with reduced double-bloom extent and an increased prevalence of single spring and no-bloom regimes. These shifts imply that contraction and weakening of the seasonal production window, with likely consequences for zooplankton growth, match–mismatch dynamics for fish early life stages, and the balance between pelagic retention and export, highlighting how MHWs and ongoing climate change can suppress and reorganize phytoplankton bloom phenology in the Gulf of Alaska.</p>","PeriodicalId":18143,"journal":{"name":"Limnology and Oceanography","volume":"71 9","pages":""},"PeriodicalIF":3.5,"publicationDate":"2026-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/lno.70487","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148895191","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":"Phosphorus availability overrides evolutionary adaptation to warming and high carbon dioxide in shaping diatom physiology and lipid metabolism","authors":"Mengcheng Ye,&nbsp;Peixuan Liu,&nbsp;Jiamin Lin,&nbsp;Siyu Luan,&nbsp;Meimei He,&nbsp;Tian Shen,&nbsp;Zexu Li,&nbsp;Bin Huang,&nbsp;Enqi Zhang,&nbsp;Junyan Li,&nbsp;Shuming Lin,&nbsp;Zihong Li,&nbsp;Jianrong Xia,&nbsp;Peng Jin","doi":"10.1002/lno.70490","DOIUrl":"10.1002/lno.70490","url":null,"abstract":"<p>Rising ocean temperatures and CO₂ concentrations are reshaping phytoplankton physiology, yet how long-term adaptation to these stressors interacts with nutrient limitation remains poorly understood. Phosphorus (P) frequently limits phytoplankton growth in coastal and stratified oceans, but it remains unclear whether adaptation to warming and elevated CO₂ modifies responses to P limitation and whether such adaptive advantages can be realized under nutrient stress. Here, we combined multi-year experimental evolution of the model diatom <i>Phaeodactylum tricornutum</i> under warming, elevated CO₂, and their combination with short-term assays across a phosphorus gradient to examine how evolutionary history influences responses to P availability. Across all adaptation regimes, P availability overwhelmingly governed growth, photosynthetic performance, and lipidome structure. Long-term adaptation increased maximum growth rate and phosphate affinity, but these advantages were largely suppressed under P limitation. Lipidomic analyses revealed extensive P-driven membrane remodeling, characterized by declines in phospholipids and increases in glycolipids and neutral lipids. While lipid-class remodeling remained highly conserved across adaptation regimes, structural lipid traits responded differently depending on both evolutionary history and phosphorus status. Under P-replete conditions, warming and elevated CO₂ primarily promoted fatty-acid elongation, whereas under P limitation they increased fatty-acid desaturation. These results demonstrate that nutrient regimes constrain evolutionary responses to warming and elevated CO₂, highlighting phosphorus as a key determinant of diatom resilience in future oceans. Increasing nutrient limitation in future oceans may therefore restrict the extent to which phytoplankton populations can realize adaptive advantages under climate change, with implications for marine productivity and biogeochemical cycling.</p>","PeriodicalId":18143,"journal":{"name":"Limnology and Oceanography","volume":"71 9","pages":""},"PeriodicalIF":3.5,"publicationDate":"2026-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148895192","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":"Closer to danger: Southern Ocean pteropods build their shells deeper in the water column during winter–spring","authors":"Pimnara Riengchan, Christine K. Weldrick, Zanna Chase, Christian Dietz, Kerrie M. Swadling","doi":"10.1002/lno.70509","DOIUrl":"https://doi.org/10.1002/lno.70509","url":null,"abstract":"Shelled pteropods are at risk from ocean acidification, with known effects on their shell durability and calcification. Pteropods typically form their aragonitic shells over specific depth ranges known as the “calcification depth,” which varies depending on species and habitats. Some Southern Ocean waters are already undersaturated with respect to aragonite and this could negatively affect shelled pteropods. However, the calcification depths of pteropods have not been determined nor used to infer consequences of changing seawater carbonate chemistry in the Southern Ocean. In this study, we analyzed the stable oxygen isotopic composition of <jats:italic>Limacina rangii</jats:italic> shells, collected by sediment traps in the sub‐Antarctic zone, to estimate their calcification depth. Shallow calcification depths (13–126 m) were detected in summer–autumn, while <jats:italic>L</jats:italic> . <jats:italic>rangii</jats:italic> calcified their shells deeper in the water column during winter–spring (302–525 m). Recent shoaling of the aragonite saturation horizon is likely to negatively affect pteropods that calcify their shells in deep water. Such shoaling could affect pteropod calcification, shell integrity and threaten population viability.","PeriodicalId":18143,"journal":{"name":"Limnology and Oceanography","volume":"28 1","pages":""},"PeriodicalIF":4.5,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149022146","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":"Decoupling of dissolved iron and iron‐binding humic‐like substances along the West Antarctic Peninsula","authors":"Laura E. Moore, Alayna Kisiday, Shannon M. Yang, P. Dreux Chappell, Randelle M. Bundy, Bethany D. Jenkins, Kristen N. Buck","doi":"10.1002/lno.70510","DOIUrl":"https://doi.org/10.1002/lno.70510","url":null,"abstract":"The chemical speciation of iron (Fe) has important ramifications for the stabilization, transport, and bioavailability of this critical nutrient. Organic ligands mediate dissolved Fe biogeochemistry such that ligand concentration and molecular composition help shape dissolved Fe distributions. Electroactive Fe‐binding humic‐like substances (“humic substances”) are one such class of ligands, a mixture thought to be predominantly comprised of degradation products of marine and terrestrial origin. Here, we examine the distributions of humic substances across large environmental gradients in dissolved Fe along the West Antarctic Peninsula in early austral spring. We found that the distributions of humic substances and dissolved Fe were decoupled. Concentrations of total Fe‐binding humic substances were tightly correlated with Fe bound to humic substances, or ambient Fe‐bound humic substances, but not with Fe, and total Fe‐binding humic substances were undersaturated in Fe across the study region. In the low Fe (&lt; 1 nM) waters of the Drake Passage, ambient Fe‐bound humic substances accounted for 10–100% of the dissolved Fe pool. Increases in Fe near the continent, however, were not associated with increases in humic substances. Rather, humic substances remained unsaturated even in elevated Fe (2.3–9.5 nM) waters inshore and ambient Fe‐bound humic substances only accounted for 2–49% of the dissolved Fe pool. Our results suggest distinct sources of Fe and humic substances near the West Antarctic Peninsula and that organic complexation of Fe by humic substances here may be strongly influenced by competition for binding sites by other cations and/or with other Fe‐binding organic ligands.","PeriodicalId":18143,"journal":{"name":"Limnology and Oceanography","volume":"9 1","pages":""},"PeriodicalIF":4.5,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149022108","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":"Biophysical structure and particle dynamics of an algal bloom within a mesoscale eddy","authors":"Kevin McGraw, Brian Ward","doi":"10.1002/lno.70504","DOIUrl":"https://doi.org/10.1002/lno.70504","url":null,"abstract":"Mesoscale eddies create dynamically distinct environments where thermohaline fronts partition the biological and optical structure of the upper water column. How these fronts organize the vertical and lateral structure of spring blooms is a longstanding observational challenge, largely because the bloom environment evolves rapidly across multiple spatial and temporal scales that are difficult to capture with conventional ship‐based sampling. This study presents a novel in situ dataset, combined with model and satellite‐derived products, examining how the thermohaline front of an anticyclonic eddy in the central Labrador Sea controls the biophysical structure of a spring bloom. The Air–Sea Interaction Profiler (ASIP), an autonomous upwardly rising float, collected 112 high‐resolution vertical profiles to 100 m depth during May 2024. Satellite observations of sea surface temperature, salinity, and chlorophyll provided complementary surface context. A well‐defined thermohaline front, marked by the 3°C isotherm and 33.8 g kg <jats:sup>−1</jats:sup> isohaline, separated a cool, fresh, productive eddy core from warmer, saltier, lower biomass surrounding waters. Within the eddy core, a shallow mixed layer of 10–40 m overlay a sharp pycnocline, below which chlorophyll fluorescence and optical backscatter organized into persistent subsurface maxima tightly coupled to the density structure. Turbulence dissipation decreased from 10 <jats:sup>−7</jats:sup> –10 <jats:sup>−6</jats:sup> W kg <jats:sup>−1</jats:sup> near the surface to 10 <jats:sup>−9</jats:sup> –10 <jats:sup>−8</jats:sup> W kg <jats:sup>−1</jats:sup> at the pycnocline, where moderate shear may have promoted large‐particle aggregation while stratification limited dispersion. Physical and biological characteristic depths shifted across the frontal boundary, demonstrating that the thermohaline front exerts control over the organization of the spring bloom.","PeriodicalId":18143,"journal":{"name":"Limnology and Oceanography","volume":"2 1","pages":""},"PeriodicalIF":4.5,"publicationDate":"2026-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"149022145","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":"Drivers of ecosystem metabolism in temperate kelp forests: A high-resolution aquatic eddy covariance study","authors":"Chang Hwa Lee,&nbsp;Karl M. Attard,&nbsp;Peter Berg,&nbsp;Yong-Jae Baek,&nbsp;Jung-Ho Hyun,&nbsp;Dong Mun Choi,&nbsp;Taihun Kim,&nbsp;Hyun Soo Rho,&nbsp;Sung-Han Kim,&nbsp;Jae Seong Lee","doi":"10.1002/lno.70484","DOIUrl":"https://doi.org/10.1002/lno.70484","url":null,"abstract":"<p>Kelp forests are highly productive coastal ecosystems that sustain organic carbon cycling and diverse food webs; however, their ecosystem metabolism remains insufficiently quantified due to a lack of suitable in situ methods. In this study, the aquatic eddy covariance technique was used to quantify oxygen (O₂) flux and net ecosystem metabolism in <i>Ecklonia cava</i> forests along Jeju Island, Korea. We also applied partial least squares regression to assess the relative influence of environmental conditions and canopy-structure metrics on O₂ flux variability. During the daytime, O₂ flux variability was primarily associated with hydrodynamic conditions and light, whereas at night, the relative importance of canopy density increased, together with temperature. This interplay between drivers was reflected in metabolic shifts of <i>E. cava</i> forests: net ecosystem metabolism was positive under dense canopies during periods of favorable light and hydrodynamic conditions but shifted toward negative values under elevated water temperature and canopy degradation. Our results demonstrate that metabolic regulation in structurally complex kelp forests is driven by a dynamic coupling of hydrodynamic forcing and biological phenology. These findings provide a critical mechanistic basis for assessing the metabolic resilience of temperate kelp forests and evaluating their potential role as nature-based solutions for carbon sequestration in a rapidly changing ocean.</p>","PeriodicalId":18143,"journal":{"name":"Limnology and Oceanography","volume":"71 9","pages":""},"PeriodicalIF":3.5,"publicationDate":"2026-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148816670","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 temperature monitoring with time-resolved wavelet analysis reveals unrecognized complexities across depth on a coral reef ecosystem","authors":"Aubrey Foulk,&nbsp;Tarik Gouhier,&nbsp;James Leichter,&nbsp;Alex S. J. Wyatt,&nbsp;Randi Rotjan,&nbsp;Mark Patterson,&nbsp;Brian Helmuth","doi":"10.1002/lno.70486","DOIUrl":"https://doi.org/10.1002/lno.70486","url":null,"abstract":"<p>Temperature variation at fine scales of minutes to hours and ~ 1–100 m is ubiquitous in marine ecosystems and often exceeds variability at larger scales. However, we know little of how well temperatures at one location or depth can serve as proxies to represent other locations, which is important in predicting thermal patterns relevant to organismal thermal stress. We used small data loggers to record fine-scale temporal variability in water temperature across a depth gradient, over multiple years, on the barrier reef system in Belize. Using pairwise correlation and wavelet coherence, which quantifies the time- and frequency-resolved correlation between pairs of time series, we examine how water temperature varies across reef zones (backreef, forereef inner, and forereef outer) and depths, and estimate the coherence of this variability across time scales. Although spectral analysis across the entire study period suggested a high degree of similarity in temperature patterns, time-resolved wavelet analyses at daily, weekly, and monthly periodicities revealed significant differences across reef-zone-by-depth combinations. We also detected a signal consistent with the Madden–Julian Oscillation. Coherence and phase locking at biologically relevant periodicities diminished with increasing depth difference between sites, suggesting that patterns at depth were not predictable from those near the surface. Overall, our findings show that wavelet analysis can reveal fine-scale thermal variation on coral reefs that coarser sampling misses, and they make clear that accurately predicting how organismal performance will shift in space and time under global change depends on collecting and analyzing depth-resolved, high-frequency, in situ data wherever possible.</p>","PeriodicalId":18143,"journal":{"name":"Limnology and Oceanography","volume":"71 9","pages":""},"PeriodicalIF":3.5,"publicationDate":"2026-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/lno.70486","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148816671","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":"Predicting passive dispersal using particle hitting distance estimates in the near field in rivers","authors":"C. R. Farrow, A. Jabbari, J. D. Ackerman","doi":"10.1002/lno.70479","DOIUrl":"https://doi.org/10.1002/lno.70479","url":null,"abstract":"Particles, including biologically relevant ones, released in rivers may interact with the bed multiple times throughout their dispersal downstream. Passive dispersal is influenced by local variations in bed morphometry and hydrodynamics, especially in the near field—the area downstream of a point source where complete mixing across the river's width has not yet occurred. We examined predictors (e.g., depth [], shear velocity [], velocity at 50% ) of the distance at which particles first contact the bed (hitting distance) using a theoretical model of turbulent transport. We identified as the strongest predictor of hitting distance and tested how different estimates of affected model predictions. We aimed to determine whether increased sampling effort (e.g., multiple estimates in a reach) improves the accuracy of the model. Specifically, we compared a reach‐based derived from the depth–slope product (DSP) vs. local estimates based on velocity measurements at 50% <jats:italic>H</jats:italic> , calculated using the turbulent kinetic energy method. We evaluated predictions against empirical data from three river reaches (Conestogo, Grand, and Speed rivers) with different hydrodynamic conditions (e.g., <jats:italic>H</jats:italic> &lt; 50 cm; 2 &lt; &lt; 5 cm s <jats:sup>−1</jats:sup> ). Model predictions based on reach‐averaged or single values (RMSE <jats:sub>local</jats:sub> = 2–3 m) were more accurate than DSP‐derived estimates (RMSE <jats:sub>DSP</jats:sub> = 3–7 m) and an implementation that accounts for longitudinal variations in local (RMSE <jats:sub>modelled</jats:sub> = 1–8 m). Our results suggest that accounting for variations in bed morphometry and hydrodynamics improves predictions of particle transport and dispersal at reach scales.","PeriodicalId":18143,"journal":{"name":"Limnology and Oceanography","volume":"2 1","pages":""},"PeriodicalIF":4.5,"publicationDate":"2026-08-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148809979","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}