Journal of Marine Systems最新文献

{"title":"Spatial variability of turbulent mixing in a highly stratified system","authors":"Débora Barros ,&nbsp;Taylor Bailey ,&nbsp;Lauren Ross ,&nbsp;Carlos A.F. Schettini","doi":"10.1016/j.jmarsys.2025.104071","DOIUrl":"10.1016/j.jmarsys.2025.104071","url":null,"abstract":"<div><div>This study investigates the lateral variability of circulation, salt distribution, and mixing processes along the highly stratified, micro-tidal Rio Grande Channel, which connects the Patos Lagoon and the Atlantic Ocean. High-resolution observations of current velocities (ADCP), water properties (CTD), and turbulent kinetic energy dissipation (microstructure profiler) were collected at three cross-sections near the lagoon mouth. The field campaign was carried out during a period of seaward flow conditions, and the cross-sections capture conditions upstream of the salt intrusion limit (freshwater/vertically homogeneous), at the landward limit of salt intrusion (the tip of the salt wedge), and downstream of the salt intrusion (highly stratified). While lagoons are often considered shallow, well-mixed systems dominated by barotropic dynamics, our results revealed pronounced stratification, with baroclinic processes playing a central role. Secondary flows driven by baroclinic pressure gradients and acceleration due to curvature and Coriolis enhanced mixing in the cross-sections. Bottom-generated mixing was evident across all transects; however, vertical shear of the horizontal current velocities at the pycnocline emerged as the primary driving mechanism in the third (most-downstream) cross-section. Stratification suppressed mixing between upper and lower layers at the midstream and downstream cross-sections, with the pycnocline damping turbulence, yet showing elevated mixing immediately above and below its interface. Notably, despite a channel-funneling effect that increased flow velocity and shear toward the mouth, mixing did not intensify as expected due to the strong stratification. These findings are particularly relevant for understanding dynamics in other microtidal estuaries, especially in choked lagoons and constricted channels.</div></div>","PeriodicalId":50150,"journal":{"name":"Journal of Marine Systems","volume":"250 ","pages":"Article 104071"},"PeriodicalIF":2.7,"publicationDate":"2025-05-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144130854","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":"Will the declining sea ice extent in the Arctic cause a reversal of net benthic-pelagic exchange directions?","authors":"Saskia Rühl ,&nbsp;Charlotte E.L. Thompson ,&nbsp;Ana M. Queirós ,&nbsp;Joanne E. Hopkins ,&nbsp;Sian F. Henley ,&nbsp;Stephen Widdicombe","doi":"10.1016/j.jmarsys.2025.104067","DOIUrl":"10.1016/j.jmarsys.2025.104067","url":null,"abstract":"<div><div>In the Arctic, loss of sea ice due to climate change and the northward shift of the Polar Front are predicted to affect many ecosystem processes such as the ecologically important process of particulate and dissolved matter exchange between the seafloor and the water column. In this study, we show for the first time that a change from an ice-covered, Arctic water-dominated system to an Atlantic -dominated ice-free one is likely to reverse seafloor-water exchange directions. A north – south transect across the Barents Sea was studied over two years with differing sea ice cover conditions, recording biological, biogeochemical, hydrographic, geophysical, and oceanographic data. There was a clear difference between the direction and magnitude of key benthic-pelagic fluxes present at Atlantic-dominated environments, and those in Arctic water – dominated ones. Currently, the southern Barents Sea exhibits a net downward flux of dissolved matter and a net upward flux of particulates, while in the northern region solutes fluctuate upwards and particulates downward, making the North a more depositional region that promotes near-surface primary productivity. Broad scale assessments of net fluxes in rapidly changing ecosystems should be employed to monitor impacts of climate change and anthropogenic activities.</div></div>","PeriodicalId":50150,"journal":{"name":"Journal of Marine Systems","volume":"249 ","pages":"Article 104067"},"PeriodicalIF":2.7,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143916828","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":"Regionally distinct drivers of the carbonate system dynamics in the Drake Passage and northern Antarctic Peninsula","authors":"Lisandro A. Arbilla ,&nbsp;Celeste López-Abbate ,&nbsp;Laura A. Ruiz-Etcheverry ,&nbsp;Azul S. Gilabert ,&nbsp;Lucía C. Kahl ,&nbsp;Ana P. Osiroff","doi":"10.1016/j.jmarsys.2025.104070","DOIUrl":"10.1016/j.jmarsys.2025.104070","url":null,"abstract":"<div><div>The Drake Passage (DP) and the adjacent northern Antarctic Peninsula (NAP) are highly dynamic regions within the Southern Ocean where physical and biogeochemical processes simultaneously influence the CO₂ system. Ocean total alkalinity (A_T) and total dissolved inorganic carbon (C_T) serve as valuable early indicators of calcium carbonate undersaturation and help evaluate the buffering capacity of the ocean. However, significant uncertainty remains in predicting carbonate system dynamics in the DP and NAP due to a lack of seasonal representation and the spatial variability. To address this uncertainty, we identified factors affecting the carbonate system at a regional level using unprecedented surface data from two consecutive austral summer and early fall periods (February–April 2003 and 2004). The data revealed that the dynamics of A_T and C_T in the DP and NAP exhibited both conservative and non-conservative behaviors influenced by the position of the Polar Front (PF), and the proximity to land. In coastal regions, salinity and terrestrial influence were major determinants, while in oceanic regions, nutrients and phytoplankton productivity played a more prominent role. The position of the PF creates a latitudinal edge in nutrient ratios, establishing a new hierarchy of carbonate chemistry drivers where silicate gains prevalence toward the southern DP and NAP. The results highlight significant regional variability in the carbonate system, with increasing A_T and C_T from north to south, making NAP the most vulnerable region due to accelerated acidification and ice melt-growth. Susceptibility to ocean acidification and seasonal fluctuations in the carbonate system indicate a higher risk to calcareous structures in the southernmost region.</div></div>","PeriodicalId":50150,"journal":{"name":"Journal of Marine Systems","volume":"249 ","pages":"Article 104070"},"PeriodicalIF":2.7,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144072070","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":"Temporal scales of variability in Regions Of Freshwater Influence on the French continental shelf over two decades","authors":"Maud Martinez Almoyna ,&nbsp;Guillaume Charria ,&nbsp;Marc Sourisseau ,&nbsp;Anne Gaymard ,&nbsp;Xavier Couvelard ,&nbsp;Sébastien Theetten ,&nbsp;Jean-François Le Roux","doi":"10.1016/j.jmarsys.2025.104068","DOIUrl":"10.1016/j.jmarsys.2025.104068","url":null,"abstract":"<div><div>The Regions Of Freshwater Influence (ROFIs) are defined as the area on the continental shelf in the vicinity of estuaries, where freshwater from the river significantly influence water properties and circulation. These regions are subject to a variety of dynamic forcings, including tides, winds and river runoffs, which exhibit considerable variability. The objective of this study is to identify the dominant time scales of variability of the three major ROFIs (Seine, Loire, and Gironde) of the French continental shelf and their evolution over the last two decades. In order to address these questions, we developed a high-resolution numerical simulation of the physical dynamics of the Bay of Biscay and the English Channel. The results demonstrate that the three ROFIs oscillate on the same two cycles: the semidiurnal cycle, caused by tides, and the annual cycle, linked to the seasonal variation in runoff. At the weekly and monthly time scales, two contrasting dynamics emerge. The Seine ROFI, situated in the eastern English Channel, is predominantly influenced by tides and exhibits a third oscillatory cycle, namely the fortnightly cycle. In the Bay of Biscay, the Loire and Gironde ROFIs are more influenced by wind events that shape their monthly variations. The interannual variations are primarily driven by runoff, with an observed reduction in ROFIs extension over the twenty years simulated correlated with a decrease in runoff. However, the combination of shorter timescale events impacts the interannual variability, leading to years with distinctive dynamics of the ROFIs.</div></div>","PeriodicalId":50150,"journal":{"name":"Journal of Marine Systems","volume":"249 ","pages":"Article 104068"},"PeriodicalIF":2.7,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144069304","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":"Light absorption properties and absorption budget of the Black Sea","authors":"Tanya Churilova ,&nbsp;Tatiana Efimova ,&nbsp;Nataliia Moiseeva ,&nbsp;Elena Skorokhod ,&nbsp;Olga Krivenko ,&nbsp;Vyacheslav Suslin","doi":"10.1016/j.jmarsys.2025.104069","DOIUrl":"10.1016/j.jmarsys.2025.104069","url":null,"abstract":"<div><div>This study is focused on bio-optical data collected from deep parts of the eastern and western Black Sea and the Crimean shelf waters during nineteen cruises of RV “Professor Vodyanitsky” carried out in different seasons in 2015–2022. Based on a long-term data set, a parameterization of light absorption by phytoplankton (<span><math><msub><mi>a</mi><mi>ph</mi></msub><mfenced><mi>λ</mi></mfenced></math></span>), non-algal particles (<span><math><msub><mi>a</mi><mi>NAP</mi></msub><mfenced><mi>λ</mi></mfenced></math></span>), and colored dissolved organic matter <span><math><msub><mi>a</mi><mi>CDOM</mi></msub><mfenced><mi>λ</mi></mfenced></math></span> was performed. Parameterization coefficients for phytoplankton absorption were revealed for all seasons. A two-fold difference was observed in the chlorophyll “a” specific light absorption coefficient of phytoplankton in the Black Sea between summer and winter seasons. The difference was related to the “pigment package effect” resulting in the self-shading of pigments caused by changes in intracellular pigment concentration and phytoplankton cell size due to adaptation of phytoplankton to the varying environmental factors. The use of seasonal-specific coefficients of parameterization of phytoplankton light absorption provides more accurate retrievals of <span><math><msub><mi>a</mi><mi>ph</mi></msub><mfenced><mi>λ</mi></mfenced></math></span> spectra based on the chlorophyll “a” concentration in modelling the light field and primary production using a spectral approach. The parameterization of CDOM light absorption and the revealed relationship between <span><math><msub><mi>a</mi><mi>CDOM</mi></msub><mfenced><mi>λ</mi></mfenced></math></span> and spectral slope (<em>S</em>_CDOM) allow one to correctly retrieve the <span><math><msub><mi>a</mi><mi>CDOM</mi></msub><mfenced><mi>λ</mi></mfenced></math></span> based on the CDOM light absorption coefficient at particular wavelength. This is applicable both for data from submersible probes and for satellite data. Accurately retrieved CDOM spectra allow more correct modelling of the light field in the sea, which is crucial for waters, where CDOM is the main optically active component. Empirically assessed spectral slope of NAP absorption and share of NAP in particulate absorption allow to differentiate CDOM and NAP based on values of their summary absorption, which can be applicable for remote sensing data interpretation. The light absorption budget reveals CDOM as the main optically active component in the Black Sea upper layer (first optical depth). The parameterization of light absorption by all optically active components can be used to refine regional models for assessing water quality and productivity indicators based on remote sensing information.</div></div>","PeriodicalId":50150,"journal":{"name":"Journal of Marine Systems","volume":"249 ","pages":"Article 104069"},"PeriodicalIF":2.7,"publicationDate":"2025-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143916830","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":"Red Sea warming and its links to the Red Sea dipole and upwelling mechanisms","authors":"Ahmed M. El Kenawy ,&nbsp;Mohammad Hadi Bordbar ,&nbsp;Emad K. Mohamed ,&nbsp;Mohamed M. Abdelaal ,&nbsp;Beatriz Fernandez-Duque ,&nbsp;Matthew F. McCabe ,&nbsp;Mohamed El Alfy ,&nbsp;Azza Ragab ,&nbsp;Hosam Ismael ,&nbsp;Shimaa Mebed ,&nbsp;Sayed M. Robaa ,&nbsp;Hassan Aboelkhair","doi":"10.1016/j.jmarsys.2025.104066","DOIUrl":"10.1016/j.jmarsys.2025.104066","url":null,"abstract":"<div><div>A comprehensive analysis of changes in sea surface temperature (SST) was performed across the Red Sea for the period 2003 to 2020 using satellite data from the Moderate Resolution Imaging Spectroradiometer (MODIS) Aqua. Employing a regionalization scheme based on principal component analysis (PCA), five homogenous sub-regions were identified that explain about 85 % of the total variation in SST across the Red Sea. The results indicate that there is a diverse and complex range of SST variability throughout the Red Sea. Spatially, distinct SST trends were observed between the southern (PC1) and northern (PC3) regions, which show northward enhancement in the rate of SST trends. A zonal contrast in the rate of warming over the western and eastern sectors was also observed, exhibiting more pronounced warming trends along the western coasts. In contrast to the offshore and deep waters, surface warming in shallow waters (depth &lt; 100 m) was more pronounced, which poses detrimental effects (e.g., thermal coral bleaching) on regional marine ecosystems. We found a robust link between spatial patterns of SST anomalies and the phases of the Red Sea Dipole (RSD). This connection was largely regulated by the upwelling associated with the local wind-stress-curl. Further, the spatial and temporal patterns of wind-driven upwelling (i.e., coastal and wind-stress-curl-driven upwelling) were reminiscent of the SST trend, highlighting the significant role of the upwelling mechanism in the SST budget and trend across the Red Sea. The positive phase of the RSD aligns with periods of stronger Toker Jet activity, reinforcing cold SST anomalies in the southern Red Sea due to enhanced upwelling-induced cooling. However, the impacts of wind-driven upwelling on local SST differ from region to region, highlighting the need to employ a high-resolution wind dataset in the simulation of SST across the Red Sea. Overall, our findings offer insights into the complex mechanisms and factors influencing SST variability in the Red Sea, thereby contributing to improving coastal zone management and environmental planning efforts.</div></div>","PeriodicalId":50150,"journal":{"name":"Journal of Marine Systems","volume":"249 ","pages":"Article 104066"},"PeriodicalIF":2.7,"publicationDate":"2025-04-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143860031","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":"Comprehensive analysis of marine heatwaves and ocean thermal structure impact on typhoon intensification in the East China Sea","authors":"Thi-Kieu-Diem Nguyen ,&nbsp;Po-Chun Hsu","doi":"10.1016/j.jmarsys.2025.104065","DOIUrl":"10.1016/j.jmarsys.2025.104065","url":null,"abstract":"<div><div>This study utilizes satellite observations and high-resolution reanalysis data to investigate the potential mechanisms of typhoon intensification in the East China Sea (ECS) from 1993 to 2022. Oceanic and atmospheric conditions within the wind radii of 30 and 50 knots surrounding typhoons were analyzed. During the study period, 30 out of 91 typhoons traversing the ECS intensified. The results show that intensified typhoons typically experienced relatively warmer sea surface temperatures and higher average ocean heat content (OHC) than non-intensified typhoons. Intensified typhoons exhibited lower vertical wind shear and slightly higher relative humidity, which helped maintain storm structure organization and enhanced upper atmospheric moisture. However, variability among individual typhoons was significant. The analysis also indicates that these favorable thermal structures, characterized by high OHC, enhance typhoon intensity with only about 40 % probability. The mixed layer depth in the ECS is generally shallow, averaging less than 25 m, with minimal variation between intensified and non-intensified typhoons, making it challenging to use ocean stratification as a determinant for typhoon intensification. Furthermore, marine heatwave (MHW) events do not significantly alter the upper ocean thermal conditions during typhoon passage, indicating that typhoon intensification due to MHWs might be exceptional, with some typhoons potentially weakening as they encounter these conditions. This study underscores the difficulties of predicting typhoon intensity changes in the ECS's complex marine environment, posing ongoing challenges for coastal disaster management.</div></div>","PeriodicalId":50150,"journal":{"name":"Journal of Marine Systems","volume":"249 ","pages":"Article 104065"},"PeriodicalIF":2.7,"publicationDate":"2025-04-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143777677","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":"Linking oceanographic conditions to foraging behaviour of southern elephant seals by characterising mid-trophic levels with an animal-borne echosounder","authors":"Marius Molinet ,&nbsp;Antoine-Peio Uhart ,&nbsp;Nadège Fonvieille ,&nbsp;Jade Chevassu ,&nbsp;Clément Castrec ,&nbsp;Martin Tournier ,&nbsp;Didier Goulet-Tran ,&nbsp;Mathilde Chevallay ,&nbsp;Ziad Sari El Dine ,&nbsp;Baptiste Picard ,&nbsp;Roy El Hourany ,&nbsp;David Nerini ,&nbsp;Christophe Guinet","doi":"10.1016/j.jmarsys.2025.104064","DOIUrl":"10.1016/j.jmarsys.2025.104064","url":null,"abstract":"<div><div>Changes in Southern Ocean thermohaline conditions could drive changes in phytoplankton community composition propagating into upper-trophic levels, from the abundance and composition of mid-trophic level communities to foraging behaviour of top marine predators. Studies exploring the ecological consequences of such processes are largely limited by our <em>in-situ</em> observation capacity. The simultaneous deployment of a miniature sonar tag, combining active acoustics and movement sensors, with oceanographic tags on 4 adult female southern elephant seals from the Kerguelen Islands provided <em>in-situ</em> measurements of thermohaline conditions, mid-trophic level abundance and seal-foraging behaviour. In addition, chlorophyll-a concentration and relative abundance of different phytoplankton size classes were assessed from satellite ocean colour data. This study reveals that east of the Kerguelen Islands, the subsurface scatterer abundance (related to mid-trophic level organisms) assessed by the sonar tag was partly positively linked to surface satellite-derived microphytoplankton biomass, especially in colder waters and frontal zones. Female elephant seals were found to dive shallower with higher subsurface scatterer abundance, which indicated a better prey accessibility, and were found to catch more prey when foraging in shallow and/or frontal zones. This study highlights the usefulness of the sonar tag, deployed on deep-diving elephant seals, to link thermohaline conditions and phytoplankton community composition in mid-trophic levels. Our result suggests that in addition to phytoplankton biomass, mid-trophic level abundance and distribution might be key factors in influencing top-marine predator foraging performances.</div></div>","PeriodicalId":50150,"journal":{"name":"Journal of Marine Systems","volume":"249 ","pages":"Article 104064"},"PeriodicalIF":2.7,"publicationDate":"2025-03-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143725650","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":"Contrasting environmental responses in an Atlantic coastal system: Recent sedimentary record from the inner Ría of Vigo (NW Spain)","authors":"Jon Gardoki ,&nbsp;Alejandro Cearreta ,&nbsp;Manel Leira ,&nbsp;José Gómez-Arozamena ,&nbsp;Víctor Villasante-Marcos ,&nbsp;Ane García-Artola ,&nbsp;María Jesús Irabien","doi":"10.1016/j.jmarsys.2025.104063","DOIUrl":"10.1016/j.jmarsys.2025.104063","url":null,"abstract":"<div><div>Anthropogenic pressures compromise the integrity of coastal systems, including the Ría of Vigo (NW Spain). Environmental reconstructions often focus on a sedimentary compartment, potentially overlooking their inherent complexities. Here, recent intertidal and subtidal sedimentary records from the inner Ría of Vigo were examined through a multi-proxy perspective, comprising micropaleontological (benthic foraminifera and diatoms), sedimentological (grain-size), organic (TOC, TN and TS) and inorganic-geochemical (Al, Cu, Pb, Zn and Ni), physical (magnetic susceptibility), and stable (δ¹³C and δ¹⁵N) and radiogenic isotope (²¹⁰Pb, ¹³⁷Cs and ^239+240Pu) proxies. The results evidence disruptions during last decades leading to contrasting responses. Intertidal compartments showed accelerated foraminiferal taphonomic loss, which obscured ecological gradients; however, diatoms and geochemistry provided insights into the mosaic of environmental factors. Subtidal bottoms experienced disturbances since the mid-20^th century, impacting benthic foraminifera and diatoms due to mussel aquaculture, urban development and hydrological changes. These processes led to hypertrophic zones with opportunistic foraminifera, benthic and higher salinity diatoms, and higher TOC, TN and δ¹⁵N. The perturbation of previous conditions affected different trophic levels and masked the intrusion of more saline waters and upwelling signals, likely facilitated by the low hydrodynamics and limited water renewal.</div></div>","PeriodicalId":50150,"journal":{"name":"Journal of Marine Systems","volume":"249 ","pages":"Article 104063"},"PeriodicalIF":2.7,"publicationDate":"2025-03-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143696886","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":"Sources of organic carbon in surface sediments of Hangzhou Bay and Zhejiang coastal area: Implication from total organic carbon, lignin and algal pigments","authors":"Yuhao Xue ,&nbsp;Qianqian Wang ,&nbsp;Xiaoyong Duan ,&nbsp;Dahai Zhang ,&nbsp;Xianguo Li","doi":"10.1016/j.jmarsys.2025.104062","DOIUrl":"10.1016/j.jmarsys.2025.104062","url":null,"abstract":"<div><div>In this study, surface sediment samples (<em>n</em> = 49) were collected from Hangzhou Bay and Zhejiang coastal area. We combine bulk parameters (total organic carbon, TOC and stable carbon isotope signature, <em>δ</em>¹³C) with both terrestrial (lignin) and marine (pigments) sources' biomarkers to elucidate the sources of organic carbon. The high contents of TOC were related to inputs from Ou River, Hangzhou Bay, Changjiang Diluted Water and Yong River. Stable carbon isotope signature (<em>δ</em>¹³C) and C/N ratio of the bulk organic matter indicated that the organic carbon in these samples was mainly derived from marine organic matters together with a little contribution from terrestrial sources. The eight lignin-phenols normalized to organic carbon (<em>Λ</em>₈) in this study were relatively low, which was attributed to the strong tidal forces in Hangzhou Bay and the shallow water depth in coastal areas. The S/V and C/V ratios of lignin-phenols demonstrated that lignin in our research area was mainly derived from angiosperms, with a small contribution from gymnosperms. The concentrations of nine pigments detected in this study were relatively low, and the concentration of fucoxanthin reduces with distance from the shoreline (in the southern area of 29°N), while the case was in the contrary for prasinoxanthin and zeaxanthin. Chlorophyll <em>a</em> was only detected in a few samples with the lowest average concentration. There was no obvious distribution characteristic of organic carbon, lignin and pigments from north to south of the entire study area, accompanied with some partial distribution features, which could be attributed to the complicated hydrodynamic conditions and diverse organic carbon sources.</div></div>","PeriodicalId":50150,"journal":{"name":"Journal of Marine Systems","volume":"249 ","pages":"Article 104062"},"PeriodicalIF":2.7,"publicationDate":"2025-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143644537","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}