Continental Shelf Research最新文献

{"title":"Microstructures along the Indian west-coast continental shelf: layering and vertical mixing","authors":"Mayur Gachake , Anoop A. Nayak , P. Amol , P.N. Vinayachandran","doi":"10.1016/j.csr.2024.105360","DOIUrl":"10.1016/j.csr.2024.105360","url":null,"abstract":"<div><div>During the month of October, the West Indian Coastal Current (WICC) is in a stage of transition from equatorward to poleward flow. The sea surface salinity near the Indian Coast is lower in the south compared to the north. Whereas the sea surface temperature is higher in the north than in the south. A salinity maximum (SM, Salinity <span><math><mo>≥</mo></math></span> 35.7 psu) exists in the sub-surface between depth ranges of 50–80 m. <em>In situ</em> vertical microstructure profiles collected along the continental shelf off the West Coast of India (WCI) for the first time, are used in this study to characterize vertical mixing under these complex thermodynamic regimes. Estimated sectional mean (median) values of the dissipation rates of turbulent kinetic energy (<span><math><mi>ɛ</mi></math></span>) and thermal variance (<span><math><mi>χ</mi></math></span>) are in the range <span><math><mrow><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mo>−</mo><mn>9</mn></mrow></msup><mo>−</mo><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mo>−</mo><mn>8</mn></mrow></msup></mrow></math></span> (<span><math><mrow><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mo>−</mo><mn>9</mn></mrow></msup><mo>−</mo><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mo>−</mo><mn>8</mn></mrow></msup></mrow></math></span>) W kg<sup>−1</sup> and <span><math><mrow><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mo>−</mo><mn>8</mn></mrow></msup><mo>−</mo><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mo>−</mo><mn>7</mn></mrow></msup></mrow></math></span> (<span><math><mrow><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mo>−</mo><mn>9</mn></mrow></msup><mo>−</mo><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mo>−</mo><mn>8</mn></mrow></msup></mrow></math></span>) <span><math><mrow><mo>°</mo><mi>C</mi></mrow></math></span> <span><math><msup><mrow></mrow><mrow><mn>2</mn></mrow></msup></math></span> s<sup>−1</sup> respectively. Sectional mean (median) values of the diapycnal diffusivity (<span><math><msub><mrow><mi>K</mi></mrow><mrow><mi>ρ</mi></mrow></msub></math></span>) and eddy thermal diffusivity (<span><math><msub><mrow><mi>K</mi></mrow><mrow><mi>T</mi></mrow></msub></math></span>) are in the range <span><math><mrow><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mo>−</mo><mn>6</mn></mrow></msup><mo>−</mo><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mo>−</mo><mn>5</mn></mrow></msup></mrow></math></span> (<span><math><mrow><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mo>−</mo><mn>6</mn></mrow></msup><mo>−</mo><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mo>−</mo><mn>5</mn></mrow></msup></mrow></math></span>) m<span><math><msup><mrow></mrow><mrow><mn>2</mn></mrow></msup></math></span> s<sup>−1</sup> and <span><math><mrow><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mo>−</mo><mn>4</mn></mrow></msup><mo>−</mo><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mo>−</mo><mn>2</mn></mrow></msup></mrow></math></span> (<span><math><mrow><mn>1</mn><msup><mrow><mn>0</mn></mrow><mrow><mo>−</mo","PeriodicalId":50618,"journal":{"name":"Continental Shelf Research","volume":"285 ","pages":"Article 105360"},"PeriodicalIF":2.1,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143145102","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Source/sink of CO2 in the southwestern part of Peter the Great Bay (sea of Japan)","authors":"Petr P. Tishchenko,&nbsp;Pavel Ya Tishchenko","doi":"10.1016/j.csr.2024.105391","DOIUrl":"10.1016/j.csr.2024.105391","url":null,"abstract":"<div><div>In this study, the carbon dioxide (CO₂) system on the continental shelf of the southwestern part of Peter the Great Bay (PGB), Sea of Japan was investigated during the autumn of 2015. During this season, the PGB represents an ocean-dominated shelf interaction system as the source of nutrients on the shelf is the subsurface part of the Sea of Japan. Weak seasonal upwelling occurred during the study period (October 20–23, 2015), forming a two-layer water structure on the shelf with a sharp pycnocline. The upper warm layer (12–15 °C) is characterized by nutrient depletion and supersaturation of dissolved oxygen concentrations (apparent oxygen utilization (AOU) &lt; 0), and it simultaneously acts as a sink to atmospheric carbon dioxide (<em>p</em>CO₂&lt;<em>p</em>CO_2atm). The layer beneath the pycnocline is characterized by low temperatures (2–5 °C) and a high concentration of nutrients; it exhibits an oxygen deficit (AOU&gt;0) and an excess of carbon dioxide (<em>p</em>CO₂&gt;<em>p</em>CO_2atm). Nitrate concentrations in the near-bottom layer of the waters suggest that these waters upwelled to the PGB shelf at depths of 200–300 m in the open Japan-East Sea. We observed a high intensity of photosynthesis corresponding to the pycnocline zone, with chlorophyll <em>a</em> concentration exceeding 10 mg/m³, which was attributed to the phytoplankton bloom. The estimated primary production in the euphotic layer of the southwestern part of PGB is up to 4.98 gC m⁻² day⁻¹. Based on the dissolved inorganic carbon (DIC)/nutrient ratio in the subsurface waters of the northwestern Sea of Japan, the shelf becomes a sink for atmospheric carbon dioxide after upwelling. Owing to the heating of surface waters during summer, the PGB acts as a source of CO₂ to the atmosphere.</div></div>","PeriodicalId":50618,"journal":{"name":"Continental Shelf Research","volume":"285 ","pages":"Article 105391"},"PeriodicalIF":2.1,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143145171","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Growth, mortality, and predatory impact on mesozooplankton of chub mackerel Scomber japonicus larvae in an upwelling system, southern Japan","authors":"Gen Kume ,&nbsp;Hiroki Oba ,&nbsp;Masafumi Kodama ,&nbsp;Taichi Shigemura ,&nbsp;Kazuhiro Shiozaki ,&nbsp;Mutsuo Ichinomiya ,&nbsp;Tomohiro Komorita ,&nbsp;Takafumi Azuma ,&nbsp;Toru Kobari","doi":"10.1016/j.csr.2024.105399","DOIUrl":"10.1016/j.csr.2024.105399","url":null,"abstract":"<div><div>In the northern Satsunan area, southern Japan, upwellings generated by the intrusion of the Kuroshio branch current into Kagoshima Bay are observed at the bay's mouth once every two weeks in winter and spring, and the resulting nutrient supply promotes phytoplankton blooms. Currently, this is a key spawning and nursery habitat for chub mackerel <em>Scomber japonicus</em> in Japan. This study examined how water temperature and prey density influenced the growth, mortality, and predatory effects of <em>S</em>. <em>japonicus</em> larvae in the northern Satsunan area. Recent growth (measured as the average width of the last three otolith increments) of <em>S. japonicus</em> larvae was positively correlated with water temperature but not with prey density, indicating that prey abundance was adequate for larvae and that water temperature controlled their growth rate in the study area. The instantaneous daily mortality rate of <em>S</em>. <em>japonicus</em> larvae was 0.322 in 2021 and 0.252 in 2022 (equivalent to 27.5% mortality d⁻¹ in 2021 and 22.3% in 2022). The food requirements of <em>S</em>. <em>japonicus</em> larvae and mesozooplankton production were 0.00427 ± 0.00334 and 6.37 ± 3.04 mg DW m⁻³ d⁻¹, respectively. <em>S</em>. <em>japonicus</em> larvae had no significant predatory impact on mesozooplankton (0.0869 ± 0.0796%). The present study suggests that none of the plankton feeders have a significant top-down regulating effect on mesozooplankton biomass in the northern Satsunan area, which provides a good food environment for S. <em>japonicus</em> larvae.</div></div>","PeriodicalId":50618,"journal":{"name":"Continental Shelf Research","volume":"285 ","pages":"Article 105399"},"PeriodicalIF":2.1,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143145283","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Assessing the sources of organic matter in sediments from the Gulf of Batabanó (Cuba) using stable isotopes, aliphatic and polycyclic aromatic hydrocarbons","authors":"Imma Tolosa ,&nbsp;Marianela Mesa-Albernas ,&nbsp;Carlos M. Alonso-Hernández","doi":"10.1016/j.csr.2025.105405","DOIUrl":"10.1016/j.csr.2025.105405","url":null,"abstract":"<div><div>Samples of superficial sediments collected along the Gulf of Batabanó, Cuba were analysed for the first time to characterize contents of biogenic and anthropogenic hydrocarbon biomarkers aiming to understand sources of hydrocarbon contamination that might contribute to biodiversity loss and fisheries decline. Total Petroleum Hydrocarbon (TPH) levels, ranging from 7.8 to 54 μg g⁻¹ dry weight, fall within the range typical for non-polluted areas, suggesting minimal anthropogenic impact. The sediment's aliphatic hydrocarbon profile further supports this, showing no signs of petrogenic contamination and a variation in total ∑n-alkanes concentration between 0.31 and 8.2 μg g⁻¹ dry weight. The presence of high concentrations of highly branched isoprenoids (HBIs), ββ hopanoid compounds, and the absence of the C32-C35 extended hopane doublets, which are indicative of crude oil pollution, point to a dominance of natural organic sources. This is corroborated by δ¹³C isotopic values of specific aliphatic biomarkers, which trace back to biogenic origins such as terrestrial plant waxes, seagrass beds, and marine plankton, with the seagrass beds being the primary contributor to the organic matter in offshore sediments. Lastly, the low-level presence of polycyclic aromatic hydrocarbons (PAHs) and their pyrolytic origin pattern suggest limited contamination, likely from combustion processes rather than direct petroleum input. This comprehensive analysis underscores the importance of ongoing monitoring to preserve the ecological integrity of such marine environment.</div></div>","PeriodicalId":50618,"journal":{"name":"Continental Shelf Research","volume":"285 ","pages":"Article 105405"},"PeriodicalIF":2.1,"publicationDate":"2025-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143145285","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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 systematic review and scientometrics analysis on microplastic pollution on coastal beaches around the globe","authors":"Nikolaos Simantiris ,&nbsp;Martha Z. Vardaki","doi":"10.1016/j.csr.2025.105424","DOIUrl":"10.1016/j.csr.2025.105424","url":null,"abstract":"<div><div>The coastlines constitute one of the most important marine environments, acting as the interface between land and sea, and a habitat for a great number of marine and terrestrial species. Coastal beaches are valuable to the coastal population, as they are of economic, ecological, cultural, and recreational importance. However, these transitional environments are subjected to several threats, with macro- and microplastic pollution directly affecting the biodiversity and coastal population. This work reviews and discusses the current state of microplastic pollution in coastal beaches around the globe in terms of occurrence, polymer types, and distribution, and describes the sources, mechanisms, and processes that control the distribution of MPs in beaches, as well as the environmental implications of microplastic pollution in these vulnerable environments.</div></div>","PeriodicalId":50618,"journal":{"name":"Continental Shelf Research","volume":"286 ","pages":"Article 105424"},"PeriodicalIF":2.1,"publicationDate":"2025-01-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143135938","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"A numerical investigation on the suspended sediment dynamics and sediment budget in the Mekong Delta","authors":"Vo Quoc Thanh ,&nbsp;Dano Roelvink ,&nbsp;Mick van der Wegen ,&nbsp;Johan Reyns ,&nbsp;Ad van der Spek ,&nbsp;Giap Van Vinh ,&nbsp;Vo Thi Phuong Linh ,&nbsp;Le Xuan Tu ,&nbsp;Nguyen Hieu Trung","doi":"10.1016/j.csr.2025.105427","DOIUrl":"10.1016/j.csr.2025.105427","url":null,"abstract":"<div><div>Fluvial sediment supply towards the coast has been the subject of extensive research. Important aspects relate to the impact of sediment retaining hydropower dams, potential delta progradation, coastal sediment supply and delta vulnerability to sea level rise. Once validated, process-based models provide a valuable tool to address these aspects and offer detailed information on sediment pathways, distribution and budget in specific systems.</div><div>This study aims to advance the understanding of the sediment dynamics and sediment budget in the Mekong Delta system. We developed a process-based model (Delft3D FM) that allows for coupling 2D area grids to 1D network grids. The flexible mesh describes both wide river sections and channel irrigation and drainage networks present in the Mekong Delta. We calibrated the model against observed discharge, salinity, suspended sediment concentration (SSC) and sediment flux.</div><div>The model was able to skillfully describe seasonal variations of SSC and hysteresis of SSC and water discharge caused by the Tonle Sap Lake induced flow patterns and seasonally varying bed sediment availability in the channels. Model results suggest that the Mekong River delivers an amount of sediment, towards the delta which is much lower than the common estimate of 160 Mt/year. About 23% of the modeled total sediment load at Kratie reaches the sea. Our modeling approach is a useful tool to assess sediment dynamics under strategic anthropogenic interventions or climate change scenarios.</div></div>","PeriodicalId":50618,"journal":{"name":"Continental Shelf Research","volume":"286 ","pages":"Article 105427"},"PeriodicalIF":2.1,"publicationDate":"2025-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143135940","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Wind-driven variability in longshore transport of SPM in the turbidity maximum zone along the Dutch coast","authors":"Carola M. van der Hout ,&nbsp;Rob Witbaard ,&nbsp;Piet Hoekstra ,&nbsp;Theo Gerkema","doi":"10.1016/j.csr.2025.105421","DOIUrl":"10.1016/j.csr.2025.105421","url":null,"abstract":"<div><div>Long-term measurements from a mooring off the Dutch coast, placed in the turbidity maximum zone (TMZ), are analyzed to study the temporal variability of the alongshore transport of SPM (Suspended Particulate Matter), covering a two-year period. In particular, the effect of wind speed and wind direction is investigated, as it is dominant over the tidal effect. The data reveal that the general net transport at the mooring location is northward; annually, the mean northward transport is 1 kton per meter in the cross-shore direction. For calm conditions, when wind speeds are less than 5 m/s, the overall effect of winds on the net transport diminishes to zero. Energetic conditions (wind speed higher than 5 m/s) are studied for a sequence of storms from opposing wind directions. Here, the gross tidal transports (i.e., transport during ebb or flood separately) show a delay with respect to the onset of the wind event, ranging from half a day to a day. The correlation between the net transport per tidal cycle and the wind characteristics during that cycle, is used to extrapolate the results to a 10-year period, using wind data from a nearby weather station. It is shown that annual transports of SPM can vary by a factor of two between years, due to different wind and wave conditions. Within a year the seasonal variability is larger, a factor of five exists between summer and winter months.</div></div>","PeriodicalId":50618,"journal":{"name":"Continental Shelf Research","volume":"286 ","pages":"Article 105421"},"PeriodicalIF":2.1,"publicationDate":"2025-01-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143135939","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Artificial intelligence applications in coastal engineering and its challenges – A review","authors":"Ali Masria ,&nbsp;Omnia Abouelsaad","doi":"10.1016/j.csr.2025.105425","DOIUrl":"10.1016/j.csr.2025.105425","url":null,"abstract":"<div><div>In the late 1980s and early 1990s, the application of Artificial Intelligence (AI) algorithms in coastal engineering began to develop, offering promising solutions to the complexity and variability of coastal environments. While traditional approaches struggle to keep up with the complexity of tackling coastal problems, particularly considering the growing concerns about climate change. In the face of climate change and other increasing natural and manmade concomitances, coastal areas contend with challenges like sea-level rise, sediment transport, water quality problems, coral reef degradation, and other coastal characteristics such as wind and tide. The paper delves into these complexities and how AI presented different techniques in a trial to enhance the predictive abilities that offer early warning systems, enhancing coastal resilience. This paper also shows Deep Learning (DL) and Machine Learning (ML) algorithms showing the different supervised and unsupervised algorithms such as Linear Regression, Long Short-Term Memory (LSTM), Support Vector Machines (SVM) etc. It also critically examines the AI-coastal engineering integration showing its drawback such as the need of more data and its limited transferability. This work also provides an overview of the current landscape of its application in coastal systems enhancing its cost-effectiveness and sustainability and considering ethical and privacy concerns.</div></div>","PeriodicalId":50618,"journal":{"name":"Continental Shelf Research","volume":"286 ","pages":"Article 105425"},"PeriodicalIF":2.1,"publicationDate":"2025-01-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143211261","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Satellite based assessment of potential fishing zones (PFZs) within the exclusive economic zone (EEZ) of Pakistan","authors":"Atifa Nadeem ,&nbsp;Asim Daud Rana ,&nbsp;Syeda Adila Batool ,&nbsp;Zia ul-Haq ,&nbsp;Ayesha Azhar ,&nbsp;Ushna Bint E Ishfaq ,&nbsp;Ammar Hameed","doi":"10.1016/j.csr.2025.105410","DOIUrl":"10.1016/j.csr.2025.105410","url":null,"abstract":"<div><div>Pakistan's Exclusive Economic Zone (EEZ) is blessed with a broad spectrum of marine life. Identification of such potential fishing zones (PFZs) can be highly profitable for sustainable fisheries by complementing to their catch and efficiency. Advancements in satellite remote sensing have made their way into marine environmental monitoring and assessment by providing reliable data about oceanographic parameters. The objective of this study is to identify PFZs using three of the crucial marine parameters, including Sea Surface Temperature (SST), Chlorophyll-a (Chl-a) and Particulate Organic Carbon (POC) concentrations. EEZ of Pakistan has been subjected with Moderate Resolution Imaging Spectroradiometer (MODIS) satellite images for a temporal window, consisting of January to December 2022. The outcomes of the study reveal that during January, February and March, the PFZs within EEZ of Pakistan is found filled with categories good and premium fishing zones, while a sharp decline is observed till the month of August due to the southwestern monsoon. In the later part of the year, PFZs starts to stretch its boundaries along the coastal area, which gradually expands in the whole EEZ with the succeeding months of the year. These results are further validated with the help of fishing activity data from Global Fishing Watch (GFW) and is also supported with meteorological data over EEZ. The study provides a cost-effective method using satellite remote sensing to identify PFZs; however, highlighting the importance of catch data accuracy for validation of PFZs distributions.</div></div>","PeriodicalId":50618,"journal":{"name":"Continental Shelf Research","volume":"286 ","pages":"Article 105410"},"PeriodicalIF":2.1,"publicationDate":"2025-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143136422","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Zooplankton of the Kara Sea in early spring: Abundance, demography, feeding and reproduction of dominant copepods Calanus spp. and Metridia longa in relation to ice retreat","authors":"A.F. Pasternak ,&nbsp;A.V. Drits ,&nbsp;E.G. Arashkevich ,&nbsp;S.E. Frenkel ,&nbsp;A.A. Nedospasov ,&nbsp;M.V. Flint","doi":"10.1016/j.csr.2025.105413","DOIUrl":"10.1016/j.csr.2025.105413","url":null,"abstract":"<div><div>Most dramatic environmental changes in the Arctic seas occur in spring, with timing of ice melt, increase of water temperature and food concentration decisive for the reproduction and recruitment success of the large copepods. In the Kara Sea, most of the studies on zooplankton community were performed at the end of the productive season. The main goal of this study is to gain knowledge on distribution, demography, grazing and reproduction of the dominant zooplankton species in the Kara Sea in early spring soon after ice retreat. Zooplankton were collected, feeding and reproduction rates studied along the retreating ice edge over the Kara Sea shelf and in the St. Anna Trough from 22 to June 30, 2021. All studied copepod species, despite different overwintering and life cycle strategies, responded similarly to the timing of ice retreat. An earlier ice melt led to higher abundance and an advanced demographical structure of the populations of dominant copepods, <em>Calanus glacialis</em>, <em>C. finmarchicus</em>, <em>C. hyperboreus</em> and <em>Metridia longa</em>. Egg production of <em>C. glacialis</em> and <em>C. finmarchicus</em> was high in the areas where the ice has recently melted. Spawning of <em>C. finmarchicus</em> females and presence of early developmental stages over the Kara Sea shelf suggests successful local recruitment of this basically boreal species. Daily rations of three <em>Calanus</em> species were high irrespective of phytoplankton concentration which indicates considerable exploitation of alternative food sources during spring post-bloom situations. Fairly low grazing impact on phytoplankton suggests that copepods community does not control spring development of phytoplankton and most part of the newly produced organic matter would be available for benthos.</div></div>","PeriodicalId":50618,"journal":{"name":"Continental Shelf Research","volume":"286 ","pages":"Article 105413"},"PeriodicalIF":2.1,"publicationDate":"2025-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143136424","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}