Continental Shelf Research最新文献

{"title":"Exploring concentration of chlorophyll-a, SST and salinity variability over the Bay of Bengal: Integrating ROMS model and in-Situ observations","authors":"Yaduvendra Singh,&nbsp;Vivek Kumar Pandey,&nbsp;Prabha Kushwaha","doi":"10.1016/j.csr.2025.105452","DOIUrl":"10.1016/j.csr.2025.105452","url":null,"abstract":"<div><div>This study is to replicate the oceanic circulation pattern in the Bay of Bengal (BoB) spanning from 1998 to 2014 using Regional Ocean Modelling Systems (ROMS). The model's performance in seizing the ocean's most vital features, such as sea-surface temperature (SST), salinity, chlorophyll-a (Chl-a) concentration, and surface currents, has been analyzed. The model represents spatial dynamics, with seasonal change progressing from the northeast to the southwest within the Bay of Bengal. From MAM, the southern BoB and central region of BoB areas demonstrate warming trends, whereas the SST increase in the northern BoB is a result of JJAS. These shifts are a result of changes in sun irradiation, mixed layer depth variations, and freshwater influx. The model shows relative alignment with the observed data, except during JJAS, where higher SSTs were observed. These higher SSTs are likely due to the intricate interactions involving monsoon-driven atmospheric variability, which impacts surface heating and freshwater influx, as well as unresolved model parameters related to vertical mixing and heat flux processes. The research work to be done requires quantification of the model's performance, and the statistical methods yield a moderate correlation for both SST and concentration of Chl-a. A variety of factors, including upwelling, coastal dynamics, and atmospheric processes, can explain these patterns. The paper emphasises the idea of the complex character of coastal processes, and it emphasises the importance of adequate representation of these phenomena in the models. The modelling of concentrations of Chl-a also exhibits a distinct seasonal trend, and the model duplicates essential features but shows biases near the coastal areas, likely due to limitations in the model's horizontal resolution, the treatment of freshwater input, and the representation of coastal upwelling processes. Positive and negative anomalies of the SST and the concentration of Chl-a are connected with the complex interaction of ocean-atmosphere systems, thereby demonstrating the interplay of different factors. Fundamentally, the research points to the significance of faithful simulation of ocean circulation and coupled elements for the proper assessment of the highly complicated BoB dynamics.</div></div>","PeriodicalId":50618,"journal":{"name":"Continental Shelf Research","volume":"289 ","pages":"Article 105452"},"PeriodicalIF":2.1,"publicationDate":"2025-03-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143644304","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":"Impact of anthropogenic activities on bacterial community diversity in a coastal city: A case study from Shantou","authors":"Jiayu Li ,&nbsp;Yue Zheng ,&nbsp;Varenyam Achal","doi":"10.1016/j.csr.2025.105450","DOIUrl":"10.1016/j.csr.2025.105450","url":null,"abstract":"<div><div>Bacterial communities in coastal environments are significantly influenced by human activities, serving as key indicators of ecological health and water quality. This study examines the impacts of anthropogenic activities on the diversity of bacterial communities within the coastal sands of Shantou, China, a rapidly developing tourist destination. We collected sand samples from four beaches with varying levels of human activity and analyzed their physicochemical properties, including pH, salinity, nitrate concentration, and available phosphorus. Bacterial community compositions were assessed using cluster heat maps to identify species distributions across multiple taxonomic levels. The results showed consistent pH levels but varied salinity and nutrient concentrations corresponding to the intensity of human activity. Notably, elevated nitrate levels at tourist-heavy sites suggested a direct link between tourism and coastal nitrogen dynamics. Five bacterial taxa were identified as potential pollution indicators, <em>Woeseia</em> and <em>Pseudomonas</em> were consistently abundant across all studied sites. Comparative analysis revealed distinct contamination patterns, with some sites showing significant microbial community shifts. These findings highlight the need for effective management strategies to mitigate the adverse effects of human activities on coastal bacterial biodiversity and ecosystem health.</div></div>","PeriodicalId":50618,"journal":{"name":"Continental Shelf Research","volume":"289 ","pages":"Article 105450"},"PeriodicalIF":2.1,"publicationDate":"2025-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143636603","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":"Mediterranean Sea: An overview of the spatial distribution of surficial sediment in relation to their origin, seabed relief and water circulation patterns","authors":"Serafeim E. Poulos","doi":"10.1016/j.csr.2025.105449","DOIUrl":"10.1016/j.csr.2025.105449","url":null,"abstract":"<div><div>The present paper provides a conclusive picture of the origin and spatial distribution of terrigenous versus biogenic carbonate material in the surficial unconsolidated seafloor sediments of the Mediterranean Sea, considering the different sources of inorganic and organic material, the seafloor relief and water circulation patterns. Terrigenous material dominates about three quarters of the Mediterranean seafloor, mainly in the central Mediterranean and the northern parts of the western and eastern Mediterranean. This dominance is attributed to significant riverine inputs and the generally oligotrophic nature of Mediterranean waters. Conversely, biogenic carbonate-rich sediments are more prevalent in the southern parts of the central and eastern Mediterranean where, despite the oligotrophic conditions, the presence of biogenic carbonate is maintained by minimal terrestrial contributions, mainly from Saharan dust deposition. Surface water circulation, although less important than riverine fluxes and primary production in shelf waters, plays an important role in sedimentation processes beyond the shelf break and is responsible for localized open sea sediment distribution patterns. Finally, anthropogenic interventions and expressions of ongoing climate change are discussed in relation to the production, transfer and deposition of both terrigenous and biogenic sediments.</div></div>","PeriodicalId":50618,"journal":{"name":"Continental Shelf Research","volume":"290 ","pages":"Article 105449"},"PeriodicalIF":2.1,"publicationDate":"2025-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143842621","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":"Dynamics of the subtidal transport through the Guafo Mouth connecting the open ocean and the Chilean Inland Sea in southern Chile","authors":"Valentina Mundaca ,&nbsp;Vincent Echevin ,&nbsp;Odette A. Vergara ,&nbsp;Osvaldo Artal ,&nbsp;Héctor H. Sepúlveda","doi":"10.1016/j.csr.2025.105428","DOIUrl":"10.1016/j.csr.2025.105428","url":null,"abstract":"<div><div>The Chilean Inland Sea (CIS) and the fjords region in Southern Chile host human activities such as salmon aquaculture. During the productive austral summer, the CIS exchanges heat, salt, dissolved oxygen, and nutrients with the Southern Pacific Ocean via the Guafo Mouth, a very shallow strait. Tides influence the productivity of the CIS, a high-frequency forcing typically not considered in circulation models when estimating exchange fluxes. In this work, the inflow, outflow, net, mass, and nutrient fluxes through the Guafo Mouth are evaluated using a high-resolution regional model forced by tides. Model output (temperature, salinity, and currents) is compared to hydrodynamic data. The impact of tidal forcing on summer-mean currents and transports is quantified. These findings are compared with results from a lower-resolution, commonly used, general circulation model. A Lagrangian modeling approach highlights that the water masses transiting from the open ocean through the Guafo Mouth mainly originate from the region south of the mouth.</div></div>","PeriodicalId":50618,"journal":{"name":"Continental Shelf Research","volume":"288 ","pages":"Article 105428"},"PeriodicalIF":2.1,"publicationDate":"2025-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143610698","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":"Corrigendum to “Biochemical implications of the Bottom Boundary Layer Detachment at the Mid-Atlantic Bight shelf-break front” [Continent. Shelf Res. 286 (2025) 105408]","authors":"Serena Negroni ,&nbsp;Dennis J. McGillicuddy ,&nbsp;Glen G. Gawarkiewicz ,&nbsp;Paolo Oddo ,&nbsp;Nadia Pinardi","doi":"10.1016/j.csr.2025.105448","DOIUrl":"10.1016/j.csr.2025.105448","url":null,"abstract":"","PeriodicalId":50618,"journal":{"name":"Continental Shelf Research","volume":"288 ","pages":"Article 105448"},"PeriodicalIF":2.1,"publicationDate":"2025-03-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143642150","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":"Disruptive synergism: The Co-occurrence of scyphozoan Pelagia noctiluca (Forsskål, 1775) swarms with green tide-causing dinoflagellate Noctiluca scintillans (Macartney) Kofoid & Swezy, 1921","authors":"Alfisa Siddique,&nbsp;Naveen Sagar Garbhapu,&nbsp;V.V.S.S. Sarma","doi":"10.1016/j.csr.2025.105447","DOIUrl":"10.1016/j.csr.2025.105447","url":null,"abstract":"<div><div>The swarming behavior of certain scyphozoan clades, such as <em>Pelagia noctiluca</em> (Forskål, 1775), highlights an evolutionary advantage. These adaptations promote survival and reproductive success, resulting in mass occurrences. <em>P. noctiluca</em>, notorious for its ecological disruption and harmful stings, swarms in response to nutrient availability. This study is the first to document the co-occurrence of a swarm of <em>P. noctiluca</em> (120–180 ind. m⁻³) and a bloom of <em>Noctiluca scintillans</em> (Macartney) Kofoid &amp; Swezy, 1921 (2.68 x 10³-4.32 × 10³ cells L⁻¹) in the Bay of Bengal, Indian Ocean. The study suggests that <em>N. scintillans</em> grazes on phytoplankton in nutrient-rich waters due to reduced competition from <em>P. noctiluca</em>'s opportunistic feeding on zooplankton. This interaction gives <em>N. scintillans</em> a competitive edge, allowing both species to co-exist and significantly impact the marine ecosystem. The proliferation of <em>N. scintillans</em>, supported by favorable conditions, is intertwined with <em>P. noctiluca</em>'s feeding dynamics, posing significant ecological and economic challenges. Continuous monitoring is essential to understand the swarming and migration patterns of <em>P. noctiluca</em> in the Indian Ocean, as their outbreaks indicate a broader ecosystem shift influenced by climate change and altered prey availability.</div></div>","PeriodicalId":50618,"journal":{"name":"Continental Shelf Research","volume":"288 ","pages":"Article 105447"},"PeriodicalIF":2.1,"publicationDate":"2025-02-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143526765","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":"Quantifying the relative contributions of forcings to the variability of estuarine surface suspended sediments using a machine learning framework","authors":"Juliana Tavora ,&nbsp;Roy El Hourany ,&nbsp;Elisa Helena Fernandes ,&nbsp;Isabel Jalón-Rojas ,&nbsp;Aldo Sotollichio ,&nbsp;Mhd Suhyb Salama ,&nbsp;Daphne van der Wal","doi":"10.1016/j.csr.2025.105429","DOIUrl":"10.1016/j.csr.2025.105429","url":null,"abstract":"<div><div>The influence of forcing mechanisms on the variability of suspended sediments in an estuary is, for the first time, synoptically quantified over prevailing ('normal') conditions and extreme events. This study investigates the complex and non-linear influence of tides, river discharge, and winds on the variability of suspended sediments in the macrotidal Gironde Estuary, France. Employing a machine learning-based framework, we integrated high-frequency field data, hourly numerical modeling outputs, and semi-daily satellite remote sensing to spatially quantify the relative contributions of forcing mechanisms. Our results reveal that tides are the primary driver of sediment variability (42.3–58.9%), followed by river discharge (21.2–34.7%) and wind (8.7–16.9%). Uncertainties range between 7% and 13.6%. In addition, the spatial variability of their contributions is consistent across numerical modeling and satellite remote sensing data, with differences not exceeding 10%. However, satellite data is limited by cloud cover and may miss extreme events. In contrast, hourly numerical modeling indicates tides are the dominant forcing mechanism under extreme events significantly affecting suspended sediment variability in the estuary. This study verifies the effectiveness of our machine learning approach against traditional Singular Spectral Analysis using field data. We demonstrate that machine learning techniques can effectively synthesize spatial distribution patterns of hydrodynamic and sedimentological variability, including the influence of winds. Our findings highlight not only the potential of satellite observations to analyze prevailing conditions despite data gaps but also that with hourly numerical modeling, the impact of forcings can be synoptically quantified under prevailing ('normal') conditions and extreme events.</div></div>","PeriodicalId":50618,"journal":{"name":"Continental Shelf Research","volume":"287 ","pages":"Article 105429"},"PeriodicalIF":2.1,"publicationDate":"2025-02-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143444638","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":"Stepwise variations of nutrients and organic matter in the fragmented Changjiang River by two big “dams”: One visible and one invisible","authors":"Ailin Yao ,&nbsp;Yue Ming ,&nbsp;Mengyu Wang ,&nbsp;Xintong Jiang ,&nbsp;Lixin Zhu ,&nbsp;Xianye Wang ,&nbsp;Lei Gao","doi":"10.1016/j.csr.2025.105438","DOIUrl":"10.1016/j.csr.2025.105438","url":null,"abstract":"<div><div>The transport flux of biogenic elements from large rivers such as the Changjiang (Yangtze) River, played a critical role in determining the estuarine and coastal environments. However, the combined effects of human activities and natural factors had resulted in complex spatiotemporal variations of biogenic elements along the river. In this study, sampling was conducted on four campaigns through the Changjiang River in different seasons during 2021 and 2022. The results showed that two suspended particulate matter (SPM) Surge Zones with rapidly increased SPM concentrations emerged, one between Yichang and Yueyang, downstream of the Three Gorges Dam (TGD), and the other between Wuhu and Xuliujing, upstream of the estuarine area. The two SPM Surge Zones had acted as the two “dams” or “walls” that separated the Changjiang River mainstream and led to the formation of two SPM Deposition Zones, one in the Three Gorges Reservoir (between Chongqing and Yichang), and the other in the middle and lower reaches (between Wuhan and Wuhu). Within these SPM Deposition Zones, SPM concentrations slowly decreased, and the proportion of particulate organic carbon in SPM increased. This reservoirization of the river water hindered the concentration increase of nutrients with the river flow, despite their continuous supplies from river banks by anthropogenic activities. The different patterns of nutrients and organic matter variations in the SPM Surge Zones and in the SPM Deposition Zones highlighted a “stepwise” characteristic in their distribution. The Changjiang River showed a deeply reservoir-like characteristic at present, which, along with other anthropogenic activities, had also driven significant decadal trends of nutrients and organic matter in the river waters.</div></div>","PeriodicalId":50618,"journal":{"name":"Continental Shelf Research","volume":"287 ","pages":"Article 105438"},"PeriodicalIF":2.1,"publicationDate":"2025-02-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143453694","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":"Why does surface chlorophyll-a bloom in Taiwan Shoal all year round?","authors":"Qi Feng ,&nbsp;Rufa’i Isyaku ,&nbsp;Yulin Zhu ,&nbsp;Ling Hao ,&nbsp;An Zhang ,&nbsp;Xin Zhou ,&nbsp;Haibin Lü","doi":"10.1016/j.csr.2025.105437","DOIUrl":"10.1016/j.csr.2025.105437","url":null,"abstract":"<div><div>Based on 10 years (January 2012–December 2021) of satellite observations, sea surface chlorophyll-a (Chl-a) was found to be present in the Taiwan Shoal throughout the year. The underlying mechanisms were investigated. The seasonal mechanism was investigated based on satellite remote sensing data, reanalysis data, and Argo buoy data. The relationship between the seasonal variation of Chl-a and sea surface temperature (SST), wind speed, photosynthetically active radiation (PAR) and salinity in Taiwan shoals was calculated. The results revealed that a large amount of Chl-a was present in the study area throughout the year, where the Chl-a concentration reached a maximum of 0.88 mg m⁻³ in July, which was 1.76 times greater than that (0.50 mg m⁻³) in April. In summer, there was increased upwelling and a thinner mixed layer, which pulled the bottom nutrients to the surface and led to the inflow of South China Sea water (SCSW) with Chl-a in the horizontal direction. In winter, the Kuroshio Branch Water (KBW) intrusion and the inflow of Chinese coastal water into the northern part of the Taiwan Strait (TWS) resulted in a zone of high temperature gradient, whereas the strong northeasterly monsoon strengthened the vertical mixing of the study area, which coincided with the zone of high Chl-a values. The combination of nutrient-rich waters, suitable temperatures in spring, and sufficient photosynthetically active radiation (PAR) in autumn provides favorable conditions for the accumulation of surface Chl-a. This study provides valuable insights into the ecological impacts of seasonal variations in Chl-a blooms in the TWS.</div></div>","PeriodicalId":50618,"journal":{"name":"Continental Shelf Research","volume":"287 ","pages":"Article 105437"},"PeriodicalIF":2.1,"publicationDate":"2025-02-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143436757","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":"Spatio-temporal variability of surface phytoplankton community structure in relation to different water systems in the east China sea coast","authors":"Anglu Shen ,&nbsp;Shuaishuai Su ,&nbsp;Haowen Li ,&nbsp;Wei Kang ,&nbsp;Rui Jia","doi":"10.1016/j.csr.2025.105426","DOIUrl":"10.1016/j.csr.2025.105426","url":null,"abstract":"<div><div>The East China Sea coast (ECS) is characterised by a diverse range of landform types, which influence the physical characteristics of the local waters. The spatio-temporal phytoplankton community structure, and the salinity, transparency, and temperature gradients were examined across six different waters of the ECS coast during four seasons. In total, 118 taxa were identified, including 86 Bacillariophyta, 16 Pyrrhophyta, and 16 other taxa. Cluster and multidimensional scaling analyses classified the six study areas into inner the estuary, outer the estuary, and in a semi-enclosed bay. Notable variations were observed in the abundance and species distribution patterns of phytoplankton across the three water types during four seasons. <em>Oscillatoria</em> spp. was the dominant species inner the estuary during the spring, summer, and winter cruises. <em>Coscinodiscus</em> spp. and <em>Skeletonema costatum</em> were the dominant species in all study areas; however, as the main dominant species, there were no significant differences in <em>Coscinodiscus</em> spp. abundance at different dimensional scales. In addition, the biodiversity index values showed no statistically significant differences among the three types of water, except during the summer cruise. Spearman's rank correlation and redundancy analyses showed that the distribution of Chlorophyta was primarily influenced by salinity. In contrast, transparency was the primary driver of phytoplankton abundance for most seasons and temperature exerted the most significant effect on phytoplankton abundance during summer. These findings indicate that physical disturbances are significant for the regulation of the phytoplankton community structure along the ECS coast.</div></div>","PeriodicalId":50618,"journal":{"name":"Continental Shelf Research","volume":"287 ","pages":"Article 105426"},"PeriodicalIF":2.1,"publicationDate":"2025-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"143394356","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}