Continental Shelf Research最新文献_第4页

Blue carbon assessment in Avicennia marina sediments and vegetation along the Red Sea Coast of Egypt: Improving methods and insights 埃及红海海岸 Avicennia marina 沉积物和植被中的蓝碳评估：改进方法和洞察力

IF 2.1 3区地球科学

Continental Shelf Research Pub Date : 2024-07-30 DOI: 10.1016/j.csr.2024.105299

{"title":"Blue carbon assessment in Avicennia marina sediments and vegetation along the Red Sea Coast of Egypt: Improving methods and insights","authors":"","doi":"10.1016/j.csr.2024.105299","DOIUrl":"10.1016/j.csr.2024.105299","url":null,"abstract":"<div><p>Mangrove forests play a crucial role in the coastal environment. A plethora of research is focusing on mangroves’ role in climate mitigation through sequestering and storing CO<sub>2</sub>. This study aims to assess the organic carbon (OC) stocks and carbon sequestration rate (CSR) of the largest stands of mangroves in the Red Sea Coast of Egypt, to evaluate their significance in climate mitigation strategies. Intensive sampling was conducted in mangrove stands of Safaga, Qulaan, and Hamata to investigate OC and sediment properties along depth intervals to 1 m deep. Additionally, OC stored in the above- and below-ground biomass was estimated using Landsat 9 OLI/TIRS satellite images. TOC content (∼0.50%) and stocks in the sediments (54.49 ± 31.71–86.00 ± 29.00 MgC/ha) were very low compared to the global average for mangrove stands, and comparable to the mangrove forest in the Middle East region. This can be attributed to the desert and semi-desert conditions, limited riverine input, and low precipitation rates. Moreover, the above-ground biomass, estimated from Normalized Difference Vegetation Index, exhibited extremely low OC storage. Therefore, the sediment acted as the main pool of organic carbon in these mangrove ecosystems. The research findings revealed that mangrove stands in Egypt exhibit low CSR, ranging from 11.94 to 18.02 g C m<sup>−2</sup> year<sup>−1</sup>. Additionally, the study determined that the stable nature of mangrove stands in Egypt makes their annual CO<sub>2</sub> emissions negligible. Despite local studies suggesting otherwise, it is highly unlikely that mangroves in Egypt contribute to the climate mitigation related to CO<sub>2</sub> sequestration. Therefore, it is important to implement restoration plans to ensure the preservation of other ecological services provided by mangroves along the Red Sea Coast.</p></div>","PeriodicalId":50618,"journal":{"name":"Continental Shelf Research","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2024-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141950253","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}

引用次数: 0

Bottom water quality plasticity in the northern gulf of Mexico hypoxic zone 墨西哥湾北部缺氧区的底层水质可塑性

IF 2.1 3区地球科学

Continental Shelf Research Pub Date : 2024-07-17 DOI: 10.1016/j.csr.2024.105295

{"title":"Bottom water quality plasticity in the northern gulf of Mexico hypoxic zone","authors":"","doi":"10.1016/j.csr.2024.105295","DOIUrl":"10.1016/j.csr.2024.105295","url":null,"abstract":"<div><p>The growth of the now ubiquitous hypoxic zones found throughout the global coastal ocean are primarily a consequence of nutrient enrichment in surface waters increasing organic production that sinks into bottom waters where oxygen is depleted faster than it is replenished. Hypoxic zones may increase or decline in number because of future climate changes. Here we summarize the summertime variations of dissolved inorganic silicate (DSi), phosphate (DIP), nitrogen (DIN; nitrate + nitrite and ammonium) and ammonium concentrations in the bottom waters of the northern Gulf of Mexico continental shelf from 1985 to 2022. The concentrations of all three are strongly correlated to oxygen concentrations, but not in the same way. At zero oxygen concentration, the annual concentrations of DSi, DIP, and ammonium changed over 38 years at a rate of 1.6 % y<sup>−1</sup>, 2.0 % y<sup>−1</sup> and -1.7 % y<sup>−1</sup>, respectively. However, the nitrate + nitrite concentrations at zero oxygen concentrations did not change over the same interval. The silicate efflux from anoxic sediments is directly related to warming temperatures and is co-related to phosphate concentrations. The bottom water DSi:DIN molar ratios increased over three decades as DIN:DIP molar ratios decreased, suggesting strong nitrogen limitation compared to silicate and phosphate, and reveal significant plasticity in regeneration rates in the bottom waters that may be dependent on changes in the surface waters. Hypoxia and food web models based on a stationary equipoise of these amounts and ratios in surface and bottom waters will likely be deficient as coastal waters warm, acidification increases, and river water quality changes. Data refreshment and improved understanding of food web changes and warming futures are recommended.</p></div>","PeriodicalId":50618,"journal":{"name":"Continental Shelf Research","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2024-07-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0278434324001250/pdfft?md5=28a2df99826928a8661d08c65cffbd9a&pid=1-s2.0-S0278434324001250-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141729367","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}

引用次数: 0

The connection of the Costa Rica Coastal Current with the West Mexican Current in the Gulf of Tehuantepec 哥斯达黎加沿岸洋流与特万特佩克湾西墨西哥洋流的联系

IF 2.1 3区地球科学

Continental Shelf Research Pub Date : 2024-07-14 DOI: 10.1016/j.csr.2024.105294

{"title":"The connection of the Costa Rica Coastal Current with the West Mexican Current in the Gulf of Tehuantepec","authors":"","doi":"10.1016/j.csr.2024.105294","DOIUrl":"10.1016/j.csr.2024.105294","url":null,"abstract":"<div><p>The interconnections of some ocean currents in the Eastern Tropical Pacific are still a mystery to the scientific community. In the Mexican Pacific, the West Mexican Current (WMC) and the Costa Rica Coastal Current (CRCC) are two flows that are typically considered independent; however, some evidence of a subsurface connection when the Tehuantepec Bowl (TB) moves westward suggests otherwise. With the Hybrid Coordinated Ocean Model (HYCOM), we obtained a 19 years-run in a domain encompassing the Eastern Tropical Pacific Ocean. The numerical results were validated qualitatively and quantitatively by comparing them with remote and direct observations. We found a generally good agreement between the model results and those observations. To analyze the model results, we defined four transects perpendicularly to the coast, and surface and subsurface layers; in the long-term mean, the CRCC is disconnected from the WMC, in both layers. However, during the seasonal cycle, we found a close relationship between the general structures in thermocline topography and surface and subsurface large-scale circulation. The model results confirmed that the interconnection between the CRCC and the WMC depends on the dynamics of the TB, that on its seasonal migration moves westward, allowing the CRCC to travel along the coast further west than the Gulf of Tehuantepec (GT) and to connect with the WMC during spring at a subsurface level below the thermocline.</p></div>","PeriodicalId":50618,"journal":{"name":"Continental Shelf Research","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2024-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141690185","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}

引用次数: 0

Seabed characterization based on the statistical classification using the seabed reflection amplitudes of sub-bottom profiler data 利用海底剖面仪数据的海底反射振幅进行统计分类，确定海底特征

IF 2.1 3区地球科学

Continental Shelf Research Pub Date : 2024-07-14 DOI: 10.1016/j.csr.2024.105293

引用次数: 0

Submesoscale features of coastal upwellings in the Black Sea: Observations and modeling 黑海沿岸上升流的次主题尺度特征：观测和建模

IF 2.1 3区地球科学

Continental Shelf Research Pub Date : 2024-07-11 DOI: 10.1016/j.csr.2024.105291

引用次数: 0

Dynamic evolution of tidal networks under the combined effect of de-reclamation and decrease of sediment supply 在围垦和沉积物供应减少共同作用下潮汐网络的动态演变

IF 2.1 3区地球科学

Continental Shelf Research Pub Date : 2024-07-05 DOI: 10.1016/j.csr.2024.105274

Shang Yu , Fan Xu , Zhong Peng , Leicheng Guo , Xianye Wang , Weiming Xie , Chunyan Zhu , Zhengbing Wang , Qing He

{"title":"Dynamic evolution of tidal networks under the combined effect of de-reclamation and decrease of sediment supply","authors":"Shang Yu , Fan Xu , Zhong Peng , Leicheng Guo , Xianye Wang , Weiming Xie , Chunyan Zhu , Zhengbing Wang , Qing He","doi":"10.1016/j.csr.2024.105274","DOIUrl":"https://doi.org/10.1016/j.csr.2024.105274","url":null,"abstract":"<div><p>De-reclamation is a common strategy used for the restoration of tidal flats. In this study, we investigate the morphodynamic response of tidal channel networks and tidal flats after de-reclamation initiatives using the Delft3D numerical model. We find that tidal channel networks that have undergone reclamation and retreat projects have a lower drainage density (8.95 km<sup>−1</sup>) than that of channel networks that formed naturally (11.33 km<sup>−1</sup>), and the drainage efficiency of natural formed channel networks is almost three times greater than restored channel networks. These findings indicate that de-reclamation alone cannot fully erase the imprinting of the previous reclamation. We also find that the ultimate effectiveness of de-reclamation is affected by the geographical layout and unchanneled path length of the inchoate main creek system. In addition, following the implementation of de-reclamation, the immediate opening of previously enclosed areas amplifies the tidal prism, thereby intensifying tidal scouring and resulting in significant erosion, with erosion rate reaching hundreds of millimeters per day. Such losses can be remediated under sufficient sediment supply and prevented through the construction of artificial channels. However, this severe erosion may escalate under an insufficient sediment supply or a heightened tidal prism, potentially leading to permanent loss. These findings constitute an important reference for future engineering practices that support the safety and sustainability of coastal resources.</p></div>","PeriodicalId":50618,"journal":{"name":"Continental Shelf Research","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2024-07-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141593156","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}

引用次数: 0

Numerical modeling of tidal propagation and frequency responses in the Guadalquivir estuary (SW, Iberian Peninsula) 瓜达尔基维尔河口（伊比利亚半岛西南部）潮汐传播和频率响应的数值模拟

IF 2.1 3区地球科学

Continental Shelf Research Pub Date : 2024-07-03 DOI: 10.1016/j.csr.2024.105275

P. Muñoz-Lopez , I. Nadal , J. García-Lafuente , S. Sammartino , A. Bejarano

{"title":"Numerical modeling of tidal propagation and frequency responses in the Guadalquivir estuary (SW, Iberian Peninsula)","authors":"P. Muñoz-Lopez , I. Nadal , J. García-Lafuente , S. Sammartino , A. Bejarano","doi":"10.1016/j.csr.2024.105275","DOIUrl":"https://doi.org/10.1016/j.csr.2024.105275","url":null,"abstract":"<div><p>A three-dimensional numerical model, based on Delft3D code, has been implemented and calibrated in the mesotidal Guadalquivir Estuary (Spain), a tidally-driven estuary due to the reduced freshwater discharges (25 m<sup>3</sup>s<sup>-1</sup> year-round average), which are subject to human regulation at the dam located at its head. The model has been applied to study in detail some estuarine features for low freshwater discharges: the first one is the non-linear interaction of semidiurnal constituents, which results in a tidal amplification factor (ratio of local amplitude to the amplitude at the mouth) that depends on the spring-neap tidal cycle, with markedly larger values during neap tides. The second one is the analysis of tidal resonance in the estuary, extending previous studies on the topic, which shows that resonance occurs at near-diurnal frequencies. The peak of resonance decreases in magnitude and shifts towards lower frequencies as friction increases, either by increasing the friction coefficient itself or the amplitude of the tide.</p></div>","PeriodicalId":50618,"journal":{"name":"Continental Shelf Research","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2024-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0278434324001055/pdfft?md5=8331531e73edf8dddc5b08052e735471&pid=1-s2.0-S0278434324001055-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141593019","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}

引用次数: 0

Observations of phytoplankton productivity and growth rates in the Malin shelf break environment 马林大陆架断裂环境中浮游植物生产力和生长率的观测结果

IF 2.1 3区地球科学

Continental Shelf Research Pub Date : 2024-07-02 DOI: 10.1016/j.csr.2024.105281

Stuart C. Painter

{"title":"Observations of phytoplankton productivity and growth rates in the Malin shelf break environment","authors":"Stuart C. Painter","doi":"10.1016/j.csr.2024.105281","DOIUrl":"10.1016/j.csr.2024.105281","url":null,"abstract":"<div><p>The southern sector of the Malin Shelf, a subregion of the NW European Shelf, is noted for episodic and unimpeded incursions of oceanic water onto the shelf in an area where the northward flowing European slope current interacts with steep bathymetry, yet the in-situ biological consequences of these incursions are largely unexplored. In this study phytoplankton productivity, nitrate assimilation and community growth rates are presented to characterise in-situ biological conditions during a prominent chlorophyll bloom that occurred at the shelf break in July 2013. Surface waters were replete with nitrate (2–7 μmol L<sup>−1</sup>) and phosphate (0.1–0.4 μmol L<sup>−1</sup>) but deficient in silicate (Si < 1 μmol L<sup>−1</sup>). Chlorophyll concentrations were significantly negatively correlated with phosphate concentrations but not correlated with nitrate or silicate. High variability between stations in productivity, nitrate assimilation, and depth averaged phytoplankton community growth rates, which ranged from <0.01 to 0.14 d<sup>−1</sup>, could be attributed to subsurface gradients in production and biomass distributions. Though variable the magnitude of productivity rates in this sector of the Malin Shelf environment do not appear unusual relative to comparable observations suggesting that despite the uncommon physical conditions of the study site phytoplankton productivity was not significantly modified by proximity to oceanic influences.</p></div>","PeriodicalId":50618,"journal":{"name":"Continental Shelf Research","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0278434324001110/pdfft?md5=f43fd1a2e75b527962424ce9b36fa015&pid=1-s2.0-S0278434324001110-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141574140","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}

引用次数: 0

Spatial trends and β-diversity of tintinnid ciliates along a salinity gradient in a temperate estuary (Río de la Plata, South America) 温带河口（南美洲拉普拉塔河）沿盐度梯度纤毛虫的空间变化趋势和 β 多样性

IF 2.1 3区地球科学

Continental Shelf Research Pub Date : 2024-07-02 DOI: 10.1016/j.csr.2024.105273

Francisco Albergoli , Viviana A. Alder

{"title":"Spatial trends and β-diversity of tintinnid ciliates along a salinity gradient in a temperate estuary (Río de la Plata, South America)","authors":"Francisco Albergoli , Viviana A. Alder","doi":"10.1016/j.csr.2024.105273","DOIUrl":"https://doi.org/10.1016/j.csr.2024.105273","url":null,"abstract":"<div><p>The response of tintinnids to frontal processes and to strong gradients of salinity and suspended particulate matter was studied in the Río de la Plata estuary, one of the widest and most turbid in the world, and characterized by a quasi-permanent salt wedge regime. The tintinnid community was explored at different depths under strong stratification conditions along the main axis of the estuary, covering from fluvial to marine coastal waters. A total of 21 taxa belonging to 10 genera (<em>Amphorides</em>, <em>Climacocylis, Codonellopsis, Eutintinnus, Luminella, Nolaclusilis, Salpingella, Stylicauda, Tintinnidium</em> and <em>Tintinnopsis</em>) were identified. The highest number of species was found at polyhaline waters. Species abundances varied within 4 orders of magnitude and allowed differentiating the tintinnid community into three main assemblages, Riverine, Mid-estuary and Marine Coastal, with highest, intermediate and lowest mean abundances, respectively. Discrepancies between ordination analyses based on environmental variables and species abundances were found in locations associated with salinity fronts. The Estuarine Turbidity Maximum matched with the highest tintinnid abundances, while the halocline hosted the highest number of species. A small variability of β-diversity and its components (Abundance Difference and Abundance Replacement) were explained by salinity, temperature and Suspended Particulate Matter. A significant correlation was found between species contributions to β-diversity and the mean Lorica Oral diameter of taxa, probably due to the influence of prey size on the spatial distribution of tintinnids. General results emphasize the importance of site-to-site physical and biological conditions in the distribution of tintinnids within the Rio de la Plata estuary.</p></div>","PeriodicalId":50618,"journal":{"name":"Continental Shelf Research","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141593017","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}

引用次数: 0

The Bonney Coast upwelling: How physical processes shape the feeding behaviour of blue whales 邦尼海岸上升流：物理过程如何塑造蓝鲸的觅食行为

IF 2.1 3区地球科学

Continental Shelf Research Pub Date : 2024-07-02 DOI: 10.1016/j.csr.2024.105277

Jochen Kämpf

{"title":"The Bonney Coast upwelling: How physical processes shape the feeding behaviour of blue whales","authors":"Jochen Kämpf","doi":"10.1016/j.csr.2024.105277","DOIUrl":"https://doi.org/10.1016/j.csr.2024.105277","url":null,"abstract":"<div><p>This study employs a fully coupled physical-biological model to explore the oceanic dynamics and phytoplankton production in one of Australia's most prominent coastal upwelling systems, the Bonney Coast Upwelling, that has barely been studied before. The study focusses on how physical processes provide two different food sources for blue whales (<em>Balaenoptera musculus</em>), namely, phytoplankton and krill (treated as nonbuoyant particles). While phytoplankton multiplies and grows rapidly within weeks in the euphotic zone in response to nutrient enrichment, krill can only be transported into the region via ambient currents. Findings of this study suggest that phytoplankton blooms appear slowly in the main upwelling plume on timescales of 4–8 weeks. Dynamical influences from incoming coastal Kelvin waves significantly weaken or strengthen this classical upwelling plume and its phytoplankton productivity. On the other hand, the upwelling-favorable wind induces a continuous coastal current that also extends eastward past the Bonney Coast. This current operates to transport and distribute krill (that cannot swim horizontally) westward along the shelf, which explains the apparent conundrum why blue whales also feed on the upstream side of the upwelling plume. The author postulates that the variability of both plankton production and the intensity of the upwelling flow (passing krill swarms along the shelf) control the feeding locations of blue whales and other baleen whales on Australia's southern shelves.</p></div>","PeriodicalId":50618,"journal":{"name":"Continental Shelf Research","volume":null,"pages":null},"PeriodicalIF":2.1,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0278434324001079/pdfft?md5=ce6389d8f54c80abc74fff9bbc2d842d&pid=1-s2.0-S0278434324001079-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141540605","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}

引用次数: 0