Journal of Marine Systems最新文献

{"title":"Spatiotemporal variations in the grain size distribution in the water column and sediments from the Yellow River Delta to distal areas under coastal currents","authors":"Lijian Yang ,&nbsp;Xiaochuan Ma ,&nbsp;Yiwei He ,&nbsp;Min Gao ,&nbsp;Jie Huang ,&nbsp;Jian Lu ,&nbsp;Zhendong Luan","doi":"10.1016/j.jmarsys.2024.103997","DOIUrl":"https://doi.org/10.1016/j.jmarsys.2024.103997","url":null,"abstract":"<div><p>The differentiation of sediment grain size from large river deltas to distal areas in a coastal flow system and its evolution are vital because they greatly contribute to matter transport, pollution accumulation, and carbon cycling on the inner shelf. Here, the Yellow River sedimentary system in the adjacent seas is studied, including the proximal delta of the Yellow River and the distal mud patch. The grain size distributions of the suspended particulate matter (SPM), surface sediments, and core sediments in the Shandong Peninsula Coastal Current (SPCC) system were integrated and analyzed. The results show that apparent variations in the grain size distribution exist in the SPM and sediments in the SPCC system. The grain size distribution of the SPM near the proximal delta of the Yellow River is multimodal and variable with water depth, whereas that in the distal mud area is typically unimodal. The coarse-grained endmember of suspended sediments is restricted in the proximal area by ocean fronts under fair weather conditions in both summer and winter and is only transported to the distal mud area under strengthened coastal currents in winter. In contrast, fine-grained endmembers can be transported far away under tidal currents and coastal currents year-round. The temporal grain size variation near the proximal delta is also significantly affected by historical shifts in the Yellow River mouth, while the strength of coastal currents associated with the East Asian Winter Monsoon (EAWM) controls the grain size distribution in the distal mud area. The roles of river behaviors, ocean fronts, tides, and winds are all highlighted in the control of grain size differentiation. These results potentially have significance for understanding sediment dynamics and mass transport processes in similar coastal current systems involving large rivers worldwide.</p></div>","PeriodicalId":50150,"journal":{"name":"Journal of Marine Systems","volume":"245 ","pages":"Article 103997"},"PeriodicalIF":2.8,"publicationDate":"2024-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141290069","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":"Investigating Labrador Sea's persistent surface O2 anomaly using observations and biogeochemical model results","authors":"Amavi N. Silva ,&nbsp;Duncan A. Purdie ,&nbsp;Nicholas R. Bates ,&nbsp;Toby Tyrrell","doi":"10.1016/j.jmarsys.2024.103996","DOIUrl":"https://doi.org/10.1016/j.jmarsys.2024.103996","url":null,"abstract":"<div><p>Deviations of surface ocean dissolved oxygen (O₂) from equilibrium with the atmosphere should be rectified about twenty times more quickly than deviations of dissolved carbon dioxide (CO₂). Therefore, persistent O₂ disequilibria in the Labrador Sea, while CO₂ is close to equilibrium, has been a matter of interest to many previous works. Here we investigate this phenomenon by using a novel analytical technique, the ‘CORS (Carbon Dioxide and Oxygen Relative to Saturation) method’, and also by using more data than was available previously. We compare observations to results from a model we developed for the Labrador Sea which combines plankton ecology with biogeochemical cycling of oxygen, carbon and nitrogen. In contrast to earlier works which mostly considered individual factors in isolation, here we used the model, together with data, to distinguish between the varying influences of several processes potentially contributing to the long-lasting O₂ undersaturation: mixed layer depth, duration of mixed layer deepening, convection, entrainment and bottom water O₂ content. Our model experiments confirm that, for the same gas exchange rate, the effects on surface O₂ concentration differ significantly among the identified drivers. Our results suggest that prolonged surface O₂ undersaturation is not always dependent on the extreme winter mixed layer depths, but rather that even moderately deep mixed layers (e.g. 300 m), when prolonged and in conjunction with continuous entrainment of oxygen-depleted deep water, can also drive persistent surface O₂ anomalies. An implication of our results is that regions in the North Atlantic with maximum winter mixed layer depths of only a few hundred metres should also show persistent surface O₂ undersaturation. We further reveal that convection in deep water formation regions produces trendlines that do not pass through the origin of a plot of CO₂ vs. O₂ deviations which have previously been thought to indicate erroneous data.</p></div>","PeriodicalId":50150,"journal":{"name":"Journal of Marine Systems","volume":"245 ","pages":"Article 103996"},"PeriodicalIF":2.8,"publicationDate":"2024-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0924796324000344/pdfft?md5=3ab28f80ed74e5e6bde616b23c18602e&pid=1-s2.0-S0924796324000344-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141303727","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 mechanism of enhanced subsurface near-inertial kinetic energy in the East China Sea associated with successive typhoons","authors":"Yang Li ,&nbsp;Zhao Xu ,&nbsp;Jie Shi ,&nbsp;Xiaohui Ma ,&nbsp;Jishang Xu","doi":"10.1016/j.jmarsys.2024.103995","DOIUrl":"10.1016/j.jmarsys.2024.103995","url":null,"abstract":"<div><p>Near-inertial waves (NIWs) play an important role in diapycnal processes and energy dissipation. A mooring observation deployed on the continental shelf in the East China Sea captured anomalously intensified subsurface near-inertial kinetic energy (NIKE) during the passage of Typhoon Danas (2013). An early study has investigated the role of Parametric Subharmonic Instability (PSI) induced by internal tides in the intensification of the subsurface intensified near-inertial velocity. However, results based on regional numerical simulations reveal that strong subsurface near-inertial velocity persists even in the absence of tidal effects, implying the existence of additional sources of NIWs. Our analyses showed that after excluding the effect of PSI, approximately 30% of the remaining subsurface NIKE can be attributed to another Typhoon Fitow (2013), which occurred a week prior to Typhoon Danas. Constrained by the Kuroshio current and the continental shelf, the NIKE generated by Typhoon Fitow propagates northward and reaches the mooring location, leading to the intensified subsurface NIW signal. Our simulation, together with the observations, suggests complicated NIW dynamics in continental shelf regions, involving interactions between successive typhoons, topography and background current, and differing from the open ocean. These interactions will further influence vertical mixing on the continental shelf along the pathway of NIW.</p></div>","PeriodicalId":50150,"journal":{"name":"Journal of Marine Systems","volume":"245 ","pages":"Article 103995"},"PeriodicalIF":2.8,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141274258","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":"Marine environmental variability in Northern Patagonia (Southwestern Atlantic Ocean) as recorded in Glycymeris longior shells","authors":"M.S. Doldan ,&nbsp;P.C. Zaidman ,&nbsp;G.N. Williams ,&nbsp;L.H. Gimenez ,&nbsp;E.M. Morsan","doi":"10.1016/j.jmarsys.2024.103991","DOIUrl":"10.1016/j.jmarsys.2024.103991","url":null,"abstract":"<div><p>Certain marine regions in the world lack long instrumental records of environmental variables or such records are incomplete. This deficiency particularly applies to Argentine Patagonia, where existing instrumental records span only the last few decades. In the present study it was explored whether such data can be reconstructed from a natural archive, specifically shells of the bivalve mollusk <em>Glycymeris longior</em> from the San Matías Gulf, north Patagonia. For this purpose, a multidecade-long time-series was constructed using variations in the annual shell growth. The time-series spans from 1890 to 2020 and is based on shells from museum collections (live-collected from 1918, 1933 and 1945) and from scientific surveys conducted between 1989 and 2021. An analysis of the links between environmental variables and shell growth was performed between 1976 and 2020 (expressed population signal &gt;0.85). The common signal among the growth curves of individual specimens of <em>G. longior</em> suggests that the growth is influenced by environmental parameters. However, the growth of <em>G. longior</em> did not show significant correlations with the low- nor with the high-frequency components of SST and food supply (chlorophyll-a concentration and POC), suggesting that these parameters do not limit shell growth at the studied site or were undetected with our analyses. The chronology also seems to be insensitive to regional climate patterns such as the Southern Annular Mode. The chronology has the potential for being expanded spatially and temporally.</p></div>","PeriodicalId":50150,"journal":{"name":"Journal of Marine Systems","volume":"245 ","pages":"Article 103991"},"PeriodicalIF":2.8,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141278596","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":"Decadal trends and dynamics in the abundance and biomass of marine branchiopods in the southern part of the North Sea","authors":"Ilias Semmouri ,&nbsp;Jonas Mortelmans ,&nbsp;Charlie Roland ,&nbsp;Colin R. Janssen ,&nbsp;Jana Asselman","doi":"10.1016/j.jmarsys.2024.103992","DOIUrl":"https://doi.org/10.1016/j.jmarsys.2024.103992","url":null,"abstract":"<div><p>Time-series are fundamental for enhancing our comprehension of plankton community dynamics and forecasting future changes that could significantly affect entire marine food chains and ecosystems. In this study, we investigated spatial and temporal variations in occurrence, abundance and body size of marine branchiopods in the Belgian Part of the North Sea (BPNS), using both traditional microscopy, as well as digital imaging (ZooSCAN). We studied the population dynamics of branchiopods collected between 2014 and 2021 in the BPNS and compared these results with a previously collected (2009–2010) dataset for the same area. The time series showed no significant changes in abundance (<em>Podon</em> spp., <em>Evadne nordmanni</em>) over the years, but we did observe a pronounced seasonal pattern, with both species completely absent in the winter months. Abundance and biomass were positively correlated with water temperature but negatively correlated with nutrient concentrations and turbidity. Additionally, <em>Podon</em> spp. abundance was negatively correlated with anthropogenic chemicals (i.e., polycyclic aromatic hydrocarbons). We employed generalized additive models to quantify the relative contribution of temperature, salinity, turbidity, chlorophyll <em>a</em> concentration and pollutant levels to the dynamics of the studied taxa. Turbidity and chlorophyll <em>a</em> concentrations were revealed to be the predictor with the highest importance in all models predicting the abundances/body size of the selected species. Anthropogenic chemicals were not informative in explaining branchiopod abundance or body size. The findings of this study establish a baseline for future studies, which is essential for our understanding of the zooplankton dynamics in the North Sea, particularly in the context of climate change and changing water quality.</p></div>","PeriodicalId":50150,"journal":{"name":"Journal of Marine Systems","volume":"245 ","pages":"Article 103992"},"PeriodicalIF":2.8,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141264247","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":"Distributions, sea-to-air fluxes, and biological consumption of carbon monoxide in the Bohai and Yellow Seas during winter","authors":"Lin Yang ,&nbsp;Jiayu Chen ,&nbsp;Jing Zhang ,&nbsp;Gui-Peng Yang ,&nbsp;Bin Yang","doi":"10.1016/j.jmarsys.2024.103994","DOIUrl":"10.1016/j.jmarsys.2024.103994","url":null,"abstract":"<div><p>Carbon monoxide (CO) concentrations in the atmosphere and ocean are mainly influenced by anthropogenic inputs, abiotic photoproduction, biogenic sources, and bacterial consumption. This study, for the first time, investigated the distributions, sea-to-air fluxes, and microbial consumption rates of CO in the Bohai Sea (BS) and the Yellow Sea (YS) in winter to identify the main factors controlling CO distributions in both the atmosphere and seawater in colder temperature. Atmospheric CO mixing ratios ([CO]_atm) and the concentrations of CO in surface seawater ([CO]_surf) ranged from 176.8 to 1245.8 ppbv (mean value: 551.4 ± 214 ppbv) and from 0.49 to 3.1 nmol L⁻¹ (mean value: 0.98 ± 0.55 nmol L⁻¹), respectively. In addition, the spatial distribution of [CO]_atm and [CO]_surf showed that anthropogenic sources dominated the distribution of [CO]_atm, but abiotic photoproduction processes were the main influencers of the distribution of [CO]_surf. The surface water at most sampling stations was supersaturated with CO, with a mean saturation factor of 1.9, and the sea-to-air fluxes of CO were estimated to range from −13.88 to 123.88 nmol m⁻² h⁻¹ (12.59 ± 21.32 nmol m⁻² h⁻¹), suggesting that the BS and the YS were the source of atmospheric CO, <!--> <!-->and were estimated to contribute 0.009% to 1.4% to the global ocean emission. Microbial consumption experiments indicated that the microbial CO consumption rate constants (<em>K</em>_bio) ranged from 0.15 to 2.14 h⁻¹, and showed that CO concentrations decreased exponentially with incubation time, suggesting that anaerobic CO consumption would limit CO accumulation in winter, thereby affecting the flux of [CO]_surf to [CO]_atm.</p></div>","PeriodicalId":50150,"journal":{"name":"Journal of Marine Systems","volume":"245 ","pages":"Article 103994"},"PeriodicalIF":2.8,"publicationDate":"2024-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141281804","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":"The Fujiwhara effect on ocean biophysical variables in the southeastern tropical Indian Ocean region","authors":"Riza Yuliratno Setiawan ,&nbsp;R. Dwi Susanto ,&nbsp;Takanori Horii ,&nbsp;Inovasita Alifdini ,&nbsp;Eko Siswanto ,&nbsp;Qurnia Wulan Sari ,&nbsp;Anindya Wirasatriya ,&nbsp;Candra Aryudiawan","doi":"10.1016/j.jmarsys.2024.103990","DOIUrl":"https://doi.org/10.1016/j.jmarsys.2024.103990","url":null,"abstract":"<div><p>A rare event known as Fujiwhara effect occurred in the southeastern tropical Indian Ocean when tropical cyclones (TCs) Seroja and Odette were co-existed, interacted each other, and merged into one TC in April 2021. Here, remotely sensed data (surface winds, sea surface temperature, chlorophyll-a concentration, and surface currents) were analyzed to determine the impact of Fujiwhara effect on the ocean biophysical variables in the region. Ekman pumping velocity were computed to determine the upwelling/downwelling process. During the entire development of the TCs to the merging, the TCs induced sea surface temperature (SST) cooling and raising sea surface chlorophyll-a. Ekman pumping and inertial pumping may serve as the primary driving force for the observed negative SST anomaly and positive anomaly in chl-a concentration associated with TCs. This rare event adds the complexity of ocean and climate dynamics of the region as an exit gate of the Indonesian throughflow to the Indian Ocean and may have implications to circulation and climate in the Indian Ocean and beyond. The present research likely represents the first scientific documentation of oceanic responses to a Fujiwhara effect in the region.</p></div>","PeriodicalId":50150,"journal":{"name":"Journal of Marine Systems","volume":"245 ","pages":"Article 103990"},"PeriodicalIF":2.8,"publicationDate":"2024-05-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141241373","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":"Extraction and interannual variation analysis of algal bloom-prone zones in the adjacent waters of the Yangtze River Estuary in summer based on GOCI data","authors":"Kexin Zhao ,&nbsp;Qian Zhao ,&nbsp;Hu Li ,&nbsp;Yanbin Xi","doi":"10.1016/j.jmarsys.2024.103989","DOIUrl":"https://doi.org/10.1016/j.jmarsys.2024.103989","url":null,"abstract":"<div><p>Harmful algal blooms (HABs) frequently threaten the health of marine environments and ecosystems in the adjacent waters of the Yangtze River Estuary (YRE) in summer. To better understand the spatiotemporal distribution, variation characteristics, and major influencing factors of algal bloom-prone zones in the adjacent waters of the YRE in summer, the present study used Geostationary Ocean Color Imager (GOCI) chlorophyll-a (Chl-a) data from 2011 to 2020. The Chl-a concentration threshold for summer algal blooms in the adjacent waters of the YRE was determined to be 16 mg/m³, based on which the monthly and interannual distribution characteristics of algal blooms were further clarified, and the influence of runoff and sea surface temperature (SST) on algal blooms was analyzed. The results showed that the area of the algal bloom-prone zones was the largest in July, at 1337 km², which was approximately 2.8-fold greater than that in June (474 km²) and 1.3-fold greater than that in August (1028 km²); the algal bloom-prone zones were mainly distributed in the eastern sea area of the YRE, and the spatial distribution of the algal blooms showed significant interannual variation. In 2020, the distribution range of the algal bloom-prone zones was the largest, and the maximum probability was &gt;20%. Runoff had a significant positive effect on the algal bloom index (BI) (<em>r</em> = 0.89, <em>p</em> &lt; 0.05), the correlation between BI and SST was weak (<em>r</em> = 0.50, <em>p</em> = 0.14), and the algal bloom probability had a significant negative correlation with SST (<em>r</em> = −0.71, <em>p</em> &lt; 0.05), implying that above a certain range of temperatures, algal growth rates may decrease with increasing temperature. The research results can provide a scientific basis for the early prevention, control, and emergency response of disasters, which is conducive to the sustainable and healthy development of marine resources and has significant scientific and management significance.</p></div>","PeriodicalId":50150,"journal":{"name":"Journal of Marine Systems","volume":"245 ","pages":"Article 103989"},"PeriodicalIF":2.8,"publicationDate":"2024-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141290666","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":"Recent changes of the dissolved oxygen distribution in the deep convection cell of the southern Adriatic Sea","authors":"R. Martellucci ,&nbsp;M. Menna ,&nbsp;E. Mauri ,&nbsp;A. Pirro ,&nbsp;R. Gerin ,&nbsp;F. Paladini de Mendoza ,&nbsp;R. Garić ,&nbsp;M. Batistić ,&nbsp;V. di Biagio ,&nbsp;P. Giordano ,&nbsp;L. Langone ,&nbsp;S. Miserocchi ,&nbsp;A. Gallo ,&nbsp;G. Notarstefano ,&nbsp;G. Savonitto ,&nbsp;A. Bussani ,&nbsp;M. Pacciaroni ,&nbsp;P. Zuppelli ,&nbsp;P.-M. Poulain","doi":"10.1016/j.jmarsys.2024.103988","DOIUrl":"10.1016/j.jmarsys.2024.103988","url":null,"abstract":"<div><p>The dynamics of dissolved oxygen in the ocean are of crucial importance for understanding marine ecosystems, with influences ranging from exchange with the atmosphere to biological processes and ocean circulation. In this study, we focus on the southern Adriatic Sea, an essential component of the Eastern Mediterranean “conveyor belt”, to investigate long-term oxygen dynamics and its driving factors. We use cross-platform datasets from 2013 to 2020, including remote sensing data, model reanalysis and in-situ observations from Argo floats, ocean gliders and ship-based measurements. Our analysis investigate the interplay of physical, biological and atmospheric forcing that drive oxygen variability. The distribution of dissolved oxygen in the southern Adriatic Sea is influenced by vertical mixing, advection of water masses and ecosystem dynamics. In the surface layer, the variability of dissolved oxygen is triggered by annual primary production and deep convection events. The dynamics in the intermediate and the deep layers are instead primarily influenced by physical processes, such as the vertical mixing and the water masses inflow from the adjacent sub-basins, which is driven by the periodic reversals of northern Ionian Gyre circulation. In particular our study reveals that the water masses advective dynamics driving the increase and decrease of dissolved oxygen have drastically changed in recent years. The highest dissolved oxygen concentrations are currently observed during the northern Ionian Gyre anticyclonic phase, while they have been previously documented during the cyclonic phase. This change appears to be connected with the significant increase in salinity observed in the southern Adriatic Sea in the same period and contributes to a better understanding of the processes that determine oxygen distribution in the Eastern Mediterranean basin.</p></div>","PeriodicalId":50150,"journal":{"name":"Journal of Marine Systems","volume":"245 ","pages":"Article 103988"},"PeriodicalIF":2.8,"publicationDate":"2024-05-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0924796324000265/pdfft?md5=677c4eb27df0ed1f422c37ebeba7e0f0&pid=1-s2.0-S0924796324000265-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141050765","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":"Assemblages of planktonic cnidarians in winter and their relationship to environmental conditions in the NW Mediterranean Sea","authors":"Marina Pastor-Prieto,&nbsp;Vanesa Raya,&nbsp;Ana Sabatés,&nbsp;Elena Guerrero,&nbsp;Joan Mir-Arguimbau,&nbsp;Josep-Maria Gili","doi":"10.1016/j.jmarsys.2024.103987","DOIUrl":"10.1016/j.jmarsys.2024.103987","url":null,"abstract":"<div><p>In the present study, we addressed the spatial characterization and species assemblages of the planktonic cnidarian community (Siphonophorae, Hydromedusae, and Scyphomedusae) in winter, a period that has been the subject of few studies in the NW Mediterranean. Data were obtained on two oceanographic cruises, in February 2017 and 2018. In 2017, the early onset of spring conditions and the subsequent phytoplankton bloom favored a mixture of winter and spring species, resulting in a higher species richness but a lower abundance of cnidarians. However, the typical winter oceanographic conditions in 2018 allowed winter species populations to develop, leading to a higher abundance of cnidarians that year. The most abundant species in both winters were <em>Lensia subtilis</em>, <em>Muggiaea kochii</em>, <em>Chelophyes appendiculata</em>, <em>Abylopsis tetragona</em> (eudoxid), <em>Aglaura hemistoma</em>, and <em>Velella velella</em> rataria larvae, while <em>Obelia</em> spp. was particularly numerous in 2017. In both years, the cluster and redundancy analyses showed a coastal-offshore ordination in species assemblages resulting from the effect of environmental variables (particularly bathymetry) and oceanographic structures (water masses and the shelf-slope density front). The presence of submarine canyons, in which great depths are reached close to the coast, modified the circulation patterns, resulting in a mixture of coastal and offshore species in these areas. In the current scenario of global warming, our results will help to provide a baseline for identifying future changes in the structure of the planktonic cnidarian community.</p></div>","PeriodicalId":50150,"journal":{"name":"Journal of Marine Systems","volume":"245 ","pages":"Article 103987"},"PeriodicalIF":2.8,"publicationDate":"2024-05-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0924796324000253/pdfft?md5=e09b9a55ea27165add485fd6a9610b1d&pid=1-s2.0-S0924796324000253-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141023045","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}