Regional Studies in Marine Science最新文献

A low-cost methodology for estimating beach-stranded plastic pellets using drone-based aerial photographs and marine natural wracks as proxy 一种低成本的方法，用于估计海滩搁浅的塑料颗粒，使用基于无人机的航空照片和海洋自然残骸作为代理

IF 2.1 4区环境科学与生态学 Q3 ECOLOGY

Regional Studies in Marine Science

Pub Date : 2025-04-25 DOI: 10.1016/j.rsma.2025.104198

G.M. Izar , T.Y. Tan , S.T. Martinez , G.O. da Rocha , A.C.R. Albergaria-Barbosa

We established a relationship between natural wrack debris and plastic pellet density on a sandy beach using Unmanned Aerial Vehicles (UAV), a low-cost quadcopter drone. Floating marine debris (natural or anthropogenic), including plastic pellets, tend to coalesce, drift, and strand together on sandy beaches. Drones are a cheap and widely available technology. Here, we verified whether it is plausible to indirectly estimate plastic pellet densities using drone aerial photos by identifying the local coverage of natural debris. Pellets and natural debris were manually sampled in situ on two beaches on the coast of São Paulo (Brazil) to verify the relationship between them. Once a model was established, drone aerial photos were taken on the largest beach (Itaguaré - 2 km in length), and heat maps of the distribution of natural debris from both methods were compared. The regression models from the field method predicted pellet densities with 45 % accuracy. Other factors not considered in this study (wave energy and sediment composition) may have influenced this accuracy. However, when comparing the pellet dispersion heat maps obtained from both methods (manual sampling and drone-based aerial photos), it can be conclude that the drone-based method was effective, especially in identifying hot spots for pellet entries onto beaches. The drone-based method allows a single person to evaluate the occurrence of plastic pellets in 35 thousand times more beach area than the conventional field methodology in just over 1 h of flight. This method is fast, easy, scalable, and accessible.

我们利用一种低成本的四轴飞行器无人机（UAV）在沙滩上建立了自然残骸碎片和塑料颗粒密度之间的关系。漂浮的海洋垃圾（自然的或人为的），包括塑料颗粒，倾向于在沙滩上聚集、漂移和搁浅在一起。无人机是一种廉价且广泛可用的技术。在这里，我们通过确定自然碎片的局部覆盖范围，验证了使用无人机航拍照片间接估计塑料颗粒密度是否合理。在圣保罗（巴西）海岸的两个海滩上对颗粒和自然碎片进行了现场人工取样，以核实它们之间的关系。一旦建立了模型，就在最大的海滩（itaguar - 2 公里长）上拍摄无人机航拍照片，并比较两种方法的自然碎片分布热图。现场法回归模型预测球团密度的准确率为45% %。本研究未考虑的其他因素（波能和沉积物组成）可能影响了这种准确性。然而，当比较两种方法（人工采样和基于无人机的航拍照片）获得的颗粒分散热图时，可以得出结论，基于无人机的方法是有效的，特别是在识别颗粒进入海滩的热点方面。基于无人机的方法允许一个人在超过1 h的飞行时间内评估塑料颗粒在比传统现场方法多3.5万倍的海滩区域的出现情况。这种方法快速、简单、可扩展且可访问。

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引用次数: 0

Assessing stock status and abundance trends of King Mackerel (Scomberomorus cavalla) using a maturity-based approach: A comparison across local and regional scales 使用基于成熟度的方法评估鲭鱼（Scomberomorus cavalla）的种群状况和丰度趋势：地方和区域尺度的比较

IF 2.1 4区环境科学与生态学 Q3 ECOLOGY

Regional Studies in Marine Science

Pub Date : 2025-04-24 DOI: 10.1016/j.rsma.2025.104207

Luís Henrique França , Alexandre Ricardo dos Santos Jr. , Walter Dennis Menezes de Oliveira , Beatrice Padovani Ferreira , Jorge Eduardo Lins Oliveira , Marcelo Francisco Nóbrega

The king mackerel (Scomberomorus cavalla) is one of the most important fishing resources in Northeast Brazil; however, little is known about the status of its stocks, largely due to a limitation of monitoring data. In this context, simple maturity-based approaches to stock status are useful to provide a general panorama of exploitation in the absence of thorough time series. We evaluated abundance (CPUE) trends and stock-status of king mackerel at regional and local scales: the REVIZEE program (1998–2000), covering almost all of Northeast Brazil, and the REPENSAPESCA project (2019–2021), with landings recorded only in the state of Rio Grande do Norte. Both projects followed handline and gillnet fleets. Abundance trends were analyzed through Generalized Additive Models (GAM). Maturity-based stock status was used to categorize size classes into juveniles, adults below optimal catch length (L_opt), adults at L_opt and mega-spawners. Abundance trends reveal the susceptibility of the species to be caught in conditions representing the outer continental shelf, likely due to an habitat preference, and higher catch in the first semester. Stock indicators show that the most frequent maturity class were adults below L_opt, while the proportion of adults within L_opt varied between 21.5 % and 30.6 %.Although gillnetting accounted for a relatively small portion of the total fishing effort, it presented a significant concern due to the high capture rate of juvenile specimens, as this gear type is known for its low selectivity. Increasing the mesh size could help reduce the capture of undersized individuals of this species. In addition, regulating the seasonal use of gillnets by avoiding periods of recruitment in this area could further minimize juvenile bycatch. Possible mega-spawners were caught within sustainable limits. All results were similar at local and regional scales, revealing the usefulness of limited monitoring and its possible application for management at different scales.

王鲭鱼（Scomberomorus cavalla）是巴西东北部重要的渔业资源之一；然而，由于监测数据有限，人们对其库存状况知之甚少。在这方面，在没有完整的时间序列的情况下，以简单的成熟度为基础的库存状况方法有助于提供开发情况的总体概况。我们在区域和地方尺度上评估了鲭鱼的丰度（CPUE）趋势和种群状况：revzee项目（1998-2000年），覆盖了几乎所有巴西东北部地区，以及REPENSAPESCA项目（2019-2021年），仅在巴西北部大州（里约热内卢Grande do Norte）有捕捞记录。这两个项目都采用了手绳和刺网船队。利用广义加性模型（GAM）分析了丰度趋势。基于成熟度的种群状态将大小分类为幼鱼、低于最佳渔获长度（Lopt）的成鱼、达到最佳渔获长度的成鱼和大型产卵鱼。丰度趋势揭示了在代表外大陆架的条件下捕获的物种的易感性，可能是由于栖息地偏好和第一学期较高的捕获量。存量指标显示，最常见的成熟度等级是Lopt以下的成虫，而Lopt内成虫的比例在21.5 %至30.6 %之间变化。虽然刺网在总捕鱼努力量中占相对较小的一部分，但由于幼鱼标本的高捕获率，因为这种渔具类型以其低选择性而闻名，因此引起了重大关注。增加网眼尺寸可以帮助减少捕获该物种体型过小的个体。此外，通过避免在这一地区的捕捞期来调节刺网的季节性使用，可以进一步减少副捕幼鱼。可能的巨型产卵者在可持续的限度内被捕获。所有结果在地方和区域尺度上相似，揭示了有限监测的有用性及其在不同尺度上管理的可能应用。

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引用次数: 0

First report of monovitellinic twin embryos of Bignose fanskate, Symterygia acuta Garman 1877 (Rajiformes, Arhynchobatidae) 大鼻扇形虫单卵黄双胚首次报道，尖尖合翅虫1877 （rajiforma, Arhynchobatidae）

IF 2.1 4区环境科学与生态学 Q3 ECOLOGY

Regional Studies in Marine Science

Pub Date : 2025-04-23 DOI: 10.1016/j.rsma.2025.104206

Paola Vivian-Vásquez , Vinicius Domingues , Maria Cristina Oddone

This study reports the first case of monovitellinic twins in Sympterygia acuta, found in its natural habitat. While embryonic development in this species typically results in a single embryo per egg capsule, two embryos were found sharing a single yolk sac. The egg capsule and embryos exhibited morphological characteristics within the normal range for the species, though differences in the size and thickness of the yolk stalk were noted. This case is compared to other reports of monozygotic twins in fish and elasmobranchs, but the exact causes remain unknown. Potential environmental or evolutionary influences are discussed.

本研究报告了在其自然栖息地发现的尖锐症状单卵黄双胞胎的第一例。虽然该物种的胚胎发育通常导致每个卵囊有一个胚胎，但发现两个胚胎共用一个卵黄囊。卵囊和胚的形态特征在正常范围内，但卵黄柄的大小和厚度存在差异。该病例与其他报道的鱼类和板鳃类同卵双胞胎进行了比较，但确切原因尚不清楚。讨论了潜在的环境或进化影响。

引用次数: 0

Regional environmental degradation after mid-2010s, possible links with flow pattern change in a semi-enclosed sea (Ise Bay, Japan) 2010年代中期以后区域环境退化与半封闭海流型变化的可能联系（伊势湾，日本）

IF 2.1 4区环境科学与生态学 Q3 ECOLOGY

Regional Studies in Marine Science

Pub Date : 2025-04-23 DOI: 10.1016/j.rsma.2025.104205

Kazuhiro Aoki , Shigeho Kakehi , Sayaka Sogawa , Kazuhiro Hanyu , Asatarou Tsuge , Rentarou Nakashima

Worldwide, oligotrophication has been revealed to be occurring under the reduction of the anthropogenic nutrient load in coastal waters. Recent environmental changes such as oligotrophication and/or climate change have been reported in previous studies, however outcomes differ depending on the situation. This study demonstrated the environmental degradation during the 2000s–2010s based on in-situ data in Ise Bay, a semi-enclosed bay in Japan, and examines about the contribution of a change in the flow pattern (offshore water intrusion) using a diagnostic hydrodynamic model. Oligotrophication, increased DIN/DIP ratio and increased thickness of the low DO water mass occurred in the mid-2010s when the fisheries yield decreased. Results of a diagnostic model suggest that the flow pattern in spring and autumn alternated to a horizontal circulation from an estuarine vertical circulation. The flow pattern change contributed to the environmental degradation (oligotrophication and hypoxia) in the western area which is hardly influenced by the offshore water intrusion.

在世界范围内，已发现在沿海水域人为营养物负荷减少的情况下发生了少营养化。最近的环境变化，如少营养化和/或气候变化，在以前的研究中已经报道过，但结果因情况而异。本研究基于日本半封闭海湾伊势湾（Ise Bay）的现场数据，展示了2000年至2010年期间的环境退化，并使用诊断水动力模型研究了流型变化（近海水入侵）的贡献。2010年代中期，渔业产量下降，低DO水体出现了富营养化现象，DIN/DIP比值增加，水体厚度增加。诊断模型的结果表明，春季和秋季的流型由河口垂直环流转变为水平环流。流型的变化导致了西部地区的环境退化（贫营养化和缺氧），而西部地区几乎不受近海水入侵的影响。

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引用次数: 0

Exploring the spatial and temporal dynamics of zooplankton assemblages in the Seomjin estuary and Gwangyang Bay, South Korea: A comparative analysis of Sequence Assignments Species (SAS) and Morphological Species Identification (MSI) Seomjin河口和光阳湾浮游动物群落的时空动态研究：序列分配物种（SAS）和形态物种鉴定（MSI）的比较分析

IF 2.1 4区环境科学与生态学 Q3 ECOLOGY

Regional Studies in Marine Science

Pub Date : 2025-04-23 DOI: 10.1016/j.rsma.2025.104201

Joo-Yeon Kang , Thodhal Yoganandham Suman , Won-Seok Kim , Jae-Won Park , Ji-Hoon Kim , Ji-Won Park , Ihn-Sil Kwak

Estuarine and coastal ecosystems are dynamic environments with strong environmental gradients that influence zooplankton community structure and distribution. Comprehending these patterns is essential for ecosystem management and biodiversity evaluation; however, traditional morphological identification consistently underestimates species diversity, as demonstrated by our comparative analysis. This research examined the structure of zooplankton communities and the distribution of copepod species along an estuarine-marine gradient in the Seomjin estuary and Gwangyang Bay, employing both Sequence Assignments Species (SAS) and Morphological Species Identification (MSI) methodologies. We collected environmental variables and zooplankton samples from six stations in May and September 2023. The Copepoda group constituted 55.1 % of the zooplankton community, with Ciliophora at 31.6 %, Meroplankton at 8.3 %, and Others at 5.0 %. SAS analysis revealed the presence of 31 copepod species distributed among three orders, exhibiting similarity values between 97.03 % and 99.29 %. We observed strong spatial and temporal variations in community structure and diversity indices. Copepod abundance significantly increased in May, especially at bay stations, whereas September showed more uniform distribution. Environmental analysis revealed that salinity and water temperature were primary drivers of species distribution, resulting in distinct species composition between estuarine and bay environments. Species diversity (H′) was consistently greater in SAS (0.69–2.92) than in MSI (0.47–1.74), with both methods indicating elevated diversity in May. NMDS analysis revealed distinct spatial separation between estuarine and bay communities, indicating the impact of environmental variables on community structure. The findings improve our understanding of zooplankton ecology in transitional waters. Both methods offer valuable insights; however, SAS consistently exhibited greater accuracy, evidenced by higher detection rates, more apparent community differences, and stronger environmental correlation, indicates its better performance for biodiversity assessment in complex estuarine ecosystems.

河口和海岸生态系统是动态环境，具有很强的环境梯度，影响着浮游动物群落的结构和分布。了解这些模式对生态系统管理和生物多样性评价至关重要；然而，我们的比较分析表明，传统的形态鉴定一直低估了物种多样性。采用序列分配物种（SAS）和形态物种鉴定（MSI）方法，研究了Seomjin河口和光阳湾沿河口-海洋梯度的浮游动物群落结构和桡足类物种分布。我们于2023年5月和9月采集了6个站点的环境变量和浮游动物样本。桡足类占浮游动物群落的55.1% %，纤毛虫占31.6% %，浮游动物占8.2% %，其他动物占5.0% %。SAS分析显示，共有31种桡足动物分布在3目中，相似性值为97.03 % ~ 99.29 %。群落结构和多样性指数存在明显的时空差异。5月桡足类丰度显著增加，特别是在海湾站，而9月分布较为均匀。环境分析表明，盐度和水温是物种分布的主要驱动因素，导致河口和海湾环境的物种组成不同。物种多样性（H′）在SAS（0.69 ~ 2.92）高于MSI(0.47 ~ 1.74)，均表明5月份物种多样性有所增加。NMDS分析显示，河口与海湾群落存在明显的空间分离，表明环境变量对群落结构的影响。这一发现提高了我们对过渡水域浮游动物生态学的认识。这两种方法都提供了有价值的见解；而SAS在复杂河口生态系统中具有较高的准确率、较高的检出率、更明显的群落差异和更强的环境相关性，表明其在复杂河口生态系统中具有更好的生物多样性评价效果。

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引用次数: 0

Long-term impacts of heavy metal contamination in the East Sea-Byeong ocean dumping site, Republic of Korea 韩国东海-炳洋倾倒场重金属污染的长期影响

IF 2.1 4区环境科学与生态学 Q3 ECOLOGY

Regional Studies in Marine Science

Pub Date : 2025-04-21 DOI: 10.1016/j.rsma.2025.104199

Hae-San Gu , Chang-Joon Kim , Jun-Mo Jung , Hye-Eun Kim , Dokyun Kim , Yeon-Su Kim , Ki-Young Choi

This study analyzed sediment samples from the East Sea-Byeong ocean dumping site in the Republic of Korea during three key years: during active ocean dumping (2009), just before the sewage sludge dumping ban (2015), and six years post-ban (2022). The study established regional background concentrations and contamination levels of eight heavy metals (Cr, Ni, Cu, Zn, As, Cd, Pb, and Hg). The results indicate a general reduction in contamination levels following regulatory measures and natural recovery processes. However, past dumping activities have a persistent influence on several indicators. In 2022, geo-accumulation index (I_geo) values for Hg, Cd, Pb, and Cr remain high, and the Pollution Load Index (PLI) also exceeds 1. Additionally, consistent patterns observed in Principal Component Analysis (PCA) and Hierarchical Cluster Analysis (HCA) further underscore this ongoing impact. This study underscores the need for long-term monitoring to track recovery, evaluate regulatory effectiveness, and support decisions for sustainable environmental management and ecosystem restoration.

本研究分析了大韩民国东海-平海洋倾倒场在三个关键年份的沉积物样本：海洋倾倒活跃期（2009 年）、禁止倾倒污水污泥前夕（2015 年）和禁止倾倒后六年（2022 年）。研究确定了八种重金属（铬、镍、铜、锌、砷、镉、铅和汞）的区域背景浓度和污染水平。结果表明，在采取监管措施和自然恢复过程后，污染水平普遍下降。不过，过去的倾倒活动对一些指标仍有影响。2022 年，汞、镉、铅和铬的地质累积指数（Igeo）值仍然很高，污染负荷指数（PLI）也超过了 1。此外，在主成分分析（PCA）和层次聚类分析（HCA）中观察到的一致模式进一步强调了这种持续影响。这项研究强调了长期监测的必要性，以便跟踪恢复情况、评估监管效果，并为可持续环境管理和生态系统恢复决策提供支持。

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引用次数: 0

Green synthesis of iron oxide nanoparticles using Momordica charantia: Kinetics of removal of heavy metal and microplastic pollutants 利用苦瓜绿色合成氧化铁纳米颗粒：去除重金属和微塑料污染物的动力学

IF 2.1 4区环境科学与生态学 Q3 ECOLOGY

Regional Studies in Marine Science

Pub Date : 2025-04-19 DOI: 10.1016/j.rsma.2025.104189

Nishita Narwal , Deeksha Katyal , Jejal Reddy Bathi

Microplastics (MPs) and heavy metals (HMs) have been contributing widely to global environmental pollution. Green and eco-friendly synthesis of nanoparticles can be a cost-effective and sustainable approach to protect aquatic ecosystems and human well being. Plant extract based nanoparticles offer major benefits as they are safer, economic, easy to obtain and have good reduction and stabilization potential. Moreover, the active agents in plants are safer to handle than conventional chemicals and microbes. To aid to the mentioned objective, iron oxide nanoparticles (IONPs) were synthesized from the fruit extract of Momordica charantia by coprecipitation method. The characterization studies were carried out using Scanning electron microscopy (SEM), Ultraviolet- Visible spectroscopy (UV-Vis), FTIR (Fourier Transform Infrared Spectroscopy), and XRD (X Ray Diffraction). Spherical shaped, reddish brown nanoparticles with size ranging from 50–70 nm were fabricated. The potential and kinetics of IONPs for the removal of carcinogenic HMs such as Lead (Pb), Cadmium (Cd) and selected MP polymer Polyamide (PA) were further investigated. The Kinetics and isothermal models brought an insight into the removal rates of HMs and MP pollutants. While the polyamide removal was best explained by Pseudo-first order kinetics and Langmuir isotherm; pseudo second-order kinetics and Freundlich isotherm models could fit to the adsorption process between HMs (Pb, Cd) and IONPs. The synthesized IONPs could be used up to four cycles with maximum removal potential of 91.59, 92.52 and 89.43 percent for Pb, Cd and polyamide respectively in the first cycle. In order to check the safety of nanoparticles for environmental applications, phytoxicity studies were conducted. Seeds of Vigna radiata were used to study the toxic effects of each pollutant and the synthesized IONPs on the shoot and root growth. Thus, these preliminary findings of the current study indicate that IONPs synthesized using green pathway could contribute to removal of emerging contaminations from aqueous media, and offer potential approach for water purification, pending further mechanistic investigation.

微塑料（MPs）和重金属（HMs）是造成全球环境污染的主要原因。绿色和生态友好的纳米颗粒合成可以是一种具有成本效益和可持续的方法，以保护水生生态系统和人类福祉。基于植物提取物的纳米颗粒具有安全、经济、易于获得和良好的还原和稳定潜力等优点。此外，植物中的活性物质比传统的化学物质和微生物处理起来更安全。为实现上述目的，以苦瓜果实提取物为原料，采用共沉淀法合成了氧化铁纳米颗粒。采用扫描电子显微镜（SEM）、紫外-可见光谱（UV-Vis）、傅里叶变换红外光谱（FTIR）和X射线衍射（XRD）进行表征研究。制备了球形红棕色纳米颗粒，粒径在50-70 nm之间。进一步研究了IONPs去除致癌物质铅（Pb）、镉（Cd）和选定的MP聚合物聚酰胺（PA）的潜力和动力学。动力学和等温模型使我们深入了解了HMs和MP污染物的去除率。而拟一级动力学和Langmuir等温线最能解释聚酰胺的去除；拟二级动力学模型和Freundlich等温线模型适合于HMs （Pb, Cd）与离子间的吸附过程。所合成的离子可循环使用4次，对Pb、Cd和聚酰胺的最大去除率分别为91.59%、92.52%和89.43%。为了验证纳米颗粒在环境应用中的安全性，进行了植物毒性研究。以辐射豇豆种子为研究对象，研究了各污染物及其合成离子对其茎、根生长的毒性作用。因此，目前研究的这些初步发现表明，使用绿色途径合成的离子螯合物可能有助于去除水介质中新出现的污染物，并为水净化提供了潜在的方法，有待进一步的机制研究。

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引用次数: 0

Characterization of microbial diversity in the harbour and ballast water of ships in the Gulf of Mannar, India using environmental DNA 利用环境DNA表征印度马纳尔湾港口和船舶压载水中的微生物多样性

IF 2.1 4区环境科学与生态学 Q3 ECOLOGY

Regional Studies in Marine Science

Pub Date : 2025-04-19 DOI: 10.1016/j.rsma.2025.104197

S. Sangeetha , A. Pavan-Kumar , J. Robina , T. RaviKumar , G. Iqbal , P. Bipul , H. Sanath Kumar , P. Krishnan , A. Chaudhari

Marine ecosystems are rich in diverse microbial communities, which are vital to nutrient cycling and the overall health of the ecosystem. Preserving native microbial diversity is crucial for maintaining ecosystem stability; however, human activities, particularly maritime shipping, pose a significant risk of introducing non-native species through ballast water discharge. Despite the ecological significance of the Gulf of Mannar, data on the microbial diversity in its harbour and ballast waters remain sparse. This study aimed to characterize the microbial diversity in the Gulf of Mannar’s harbour and ballast waters using 16S rRNA amplicon sequencing. Analysis revealed the presence of dominant phyla, including Proteobacteria, Bacteroidetes, Planctomycetes, and Actinobacteria, in both water sources, underscoring their significant ecological roles. At the genus level, ballast water was dominated by species such as Alteromonas, Neptuniibacter, Aestuariibacter, Pirellula, Pseudoalteromonas, Thalassotalea, Rubripirellula, Vibrio, Algicola, and Blastopirellula, while harbour water exhibited species abundance from genera like Alteromonas, Oleibacter, Uncultured-bacterium, Pirellula, Blastopirellula, Tropicimonas, Marinobacter, Neptuniibacter, Illumatobacter, and Candidatus-actinomarina. Diversity indices showed higher species richness in harbour water but greater abundance in ballast water. Significant differences in species abundance were identified between the two environments, notably in Oleiphilus messimensis, a haloalkaliphilic bacterium (Acht6.2), various species within Marinobacter and Marinomonas, and the orders Verrucomicrobiales and Dadabacteriales. This study provides a baseline of microbial biodiversity in the Gulf of Mannar’s harbour and ballast waters, offering insights into microbial community dynamics and informing management strategies to mitigate ecological risks linked to ballast water discharge in the region.

海洋生态系统中有丰富的微生物群落，它们对营养循环和生态系统的整体健康至关重要。保护本地微生物多样性对维持生态系统稳定至关重要；然而，人类活动，特别是海上运输，通过压载水排放带来了引入非本地物种的重大风险。尽管马纳尔湾具有重要的生态意义，但关于其港口和压载水中微生物多样性的数据仍然很少。本研究旨在利用16S rRNA扩增子测序来表征马纳尔湾港口和压载水中的微生物多样性。分析显示，两种水源中均存在优势门，包括变形菌门、拟杆菌门、plantomycetes和放线菌门，强调其重要的生态作用。在属水平上，压载水中以Alteromonas、Neptuniibacter、aestuaribacter、Pirellula、Pseudoalteromonas、Thalassotalea、Rubripirellula、Vibrio、Algicola和Blastopirellula等属为主，港湾水中则以Alteromonas、Oleibacter、uncultulebacterium、Pirellula、Blastopirellula、Tropicimonas、Marinobacter、Neptuniibacter、Illumatobacter和Candidatus-actinomarina等属为主。多样性指数显示，港口水域的物种丰富度较高，压载水的物种丰富度较高。在两种环境中，物种丰度存在显著差异，特别是嗜盐嗜碱菌（Acht6.2）嗜盐嗜碱菌（Oleiphilus messimensis）、Marinobacter和Marinomonas中的各种物种以及Verrucomicrobiales和Dadabacteriales。本研究提供了马纳尔湾港口和压载水微生物生物多样性的基线，提供了微生物群落动态的见解，并为管理策略提供信息，以减轻该地区压载水排放相关的生态风险。

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引用次数: 0

Leveraging structural topic modeling to compare “Green Port” research and practice 利用结构性主题模型比较“绿色港口”的研究与实践

IF 2.1 4区环境科学与生态学 Q3 ECOLOGY

Regional Studies in Marine Science

Pub Date : 2025-04-18 DOI: 10.1016/j.rsma.2025.104196

Hui Zhuang , Yang Chen , Sen Gu , Thierry Vanelslander

Although the concept of “green ports” was first introduced by practitioners in the 2000s and attracted significant attention from academia, academic investigations have not comprehensively reflected practitioners’ concerns. To narrow the gaps in the definition of the concept between academia and practitioners and to avoid unclear understandings that jeopardize the value of related research, this study investigates practitioners’ perceptions of green ports through the theoretical lens developed by academia and to identify and explain these gaps. Natural language processing, one of the most advanced text mining methods, is applied to analyze 1781 chunks of green port-related text retrieved from 123 corporate social responsibility reports released by 15 mainland Chinese listed port companies from 2010 to 2021. The results suggest the following: (1) while there is a general consensus between academia and practitioners, significant differences emerge in certain topics, such as noise pollution, land pollution, safety management, and green education. (2) The dynamic and socially constructed nature of green ports is highlighted, suggesting that the influence of the external socioeconomic environment, including site disparity, social patterns and significant local disasters, should be integrated into future research. Finally, suggestions for narrowing the gap between academia and practitioners regarding perceptions of green ports are proposed.

虽然“绿色港口”的概念在21世纪初由实践者首次提出，并引起了学术界的广泛关注，但学术调查并未全面反映实践者的担忧。为了缩小学术界与实践者在概念定义上的差距，避免认识不清危及相关研究的价值，本研究通过学术界发展的理论视角调查实践者对绿色港口的看法，并识别和解释这些差距。本文采用最先进的文本挖掘方法之一自然语言处理，对中国内地15家港口上市公司2010年至2021年发布的123份企业社会责任报告中的1781条绿色港口相关文本进行了分析。结果表明：(1)学术界和实践者在噪声污染、土地污染、安全管理和绿色教育等议题上存在显著差异，但学术界和实践者之间存在普遍共识。(2)强调了绿色港口的动态性和社会建构性，建议在未来的研究中考虑外部社会经济环境的影响，包括场地差异、社会格局和重大地方灾害。最后，提出了缩小学术界和实践者在绿色港口认知上差距的建议。

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引用次数: 0

Unveiling the seismic attenuation characteristics in the mantle beneath Southeast Asia: Insights into mantle dynamics and tectonic processes 揭示东南亚地幔地震衰减特征：对地幔动力学和构造过程的认识

IF 2.1 4区环境科学与生态学 Q3 ECOLOGY

Regional Studies in Marine Science

Pub Date : 2025-04-17 DOI: 10.1016/j.rsma.2025.104192

Van-Duong Nguyen , Le-Minh Nguyen , Cong-Nghia Nguyen , Thi-Giang Ha , Vinh-Long Ha , Tien-Hung Nguyen , Quang-Khoi Le

In this paper, we analyze the Q value characteristics of the mantle beneath Southeast Asia (SE) using multiple ScS and sScS phases recorded at 78 seismic stations. The seismic attenuation in the mantle beneath the East Vietnam Sea (EVS) and the surroundings has been examined by applying the spectral ratio method to the multiple ScS₃/ScS₂ and sScS₃/sScS₂ phases recorded at seismic broadband stations surrounding the EVS region. The estimated average Q values for the EVS region for the ScS and sScS are 71.7 ± 49.1 and 86.0 ± 54.8 respectively, which are relatively low and fall within the range of volcanic active regions suggesting a relatively hot mantle beneath, which may reflect the spreading process of the EVS. Moreover, the Q values exhibit strong lateral variation based on the ray path propagating through different tectonic structures. Compared with the seismic tomography models and thermal structure of the region, the low Q value is observed along the ray paths that bounce regions with mantle wedge melting and subduction process present. In contrast, the high Q value of some source-station pairs might be explained by the low temperature of the shallow part of the upper mantle in the EVS central, suggesting the cessation of the spreading process in the Miocene.

本文利用78个地震台站记录的多个南海和南海相，分析了东南亚地区地幔的Q值特征。利用谱比法对东越南海（EVS）周边宽带地震台站记录的多个ScS3/ScS2相和sScS3/sScS2相进行了地震衰减研究。南海和南海的EVS区平均Q值分别为71.7 ± 49.1和86.0 ± 54.8，相对较低，处于火山活动区范围内，表明地幔温度较高，可能反映了EVS的扩张过程。此外，根据不同构造的射线传播路径，Q值表现出强烈的横向变化。与地震层析成像模型和该地区的热结构相比较，在地幔楔块熔融和俯冲过程存在的弹跳区的射线路径上观察到低Q值。相反，一些源站对的高Q值可能是由于EVS中心上地幔浅部温度较低，表明扩张过程在中新世停止。

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