Marine environmental research最新文献_第6页

Multi-pathway nutrient replenishment mechanisms sustaining the transboundary green tides region in the Southern Yellow sea 南黄海跨界绿潮区多通道养分补给机制的维持

IF 3.2 3区环境科学与生态学 Q2 ENVIRONMENTAL SCIENCES

Marine environmental research

Pub Date : 2026-01-18 DOI: 10.1016/j.marenvres.2026.107865

Xin Li , Hong Gao , Chuansong Zhang , Xiaoyong Shi

Large-scale macroalgal blooms represent a critical environmental challenge for coastal regions worldwide, driven primarily by human-induced eutrophication. Since 2007, the Southern Yellow Sea (SYS) in China has experienced massive green tides of Ulva prolifera (U.prolifera) each summer, persistently impacting the coastal economies, ecosystems, and social well-being of Jiangsu and Shandong provinces. This study systematically quantified the contribution of different nutrient sources to the migration path of green tide in the outbreak area. The analysis was mainly based on field monitoring data from 2017, supplemented by historical datasets. Results show that atmospheric deposition acts as a key cross-regional driver, accounting for 70 %, 34 %, 54 %, 76 %, and 64 % of dissolved inorganic nitrogen (DIN), dissolved inorganic phosphorus (DIP), dissolved silicon (DSi), dissolved organic nitrogen (DON), and dissolved organic phosphorus (DOP), respectively. Meanwhile, terrestrial inputs in the Subei Shoal—including river input and marine aquaculture—provide 25 % of DIN and 46 % of DIP, forming an essential nutrient base for the initial bloom development. As algal biomass drifted northward to the coastal waters of Shandong Peninsula, continuous atmospheric nutrient deposition became a key driver for the expansion of the green tide. This study quantitatively elucidates the transboundary effects of atmospheric and terrestrial nutrient inputs, offering scientific support for nutrient management strategies in coastal marine systems.

大规模的大型藻华是全球沿海地区面临的严峻环境挑战，主要由人类引起的富营养化驱动。自2007年以来，中国南黄海（SYS）每年夏季都会出现大规模的藻绿潮，持续影响着江苏和山东沿海的经济、生态系统和社会福祉。本研究系统量化了不同营养源对暴发区绿潮迁移路径的贡献。分析主要基于2017年的现场监测数据，并辅以历史数据集。结果表明，大气沉降是主要的跨区域驱动因素，分别占溶解无机氮（DIN）、溶解无机磷（DIP）、溶解硅（DSi）、溶解有机氮（DON）和溶解有机磷（DOP）的70%、34%、54%、76%和64%。同时，苏北浅滩的陆源输入（包括河流输入和海洋养殖）提供了25%的DIN和46%的DIP，形成了初始水华发展所必需的营养基础。随着藻生物量向北漂移至山东半岛近岸水域，持续的大气营养物沉积成为绿潮扩展的关键驱动力。本研究定量阐明了大气和陆地养分输入的跨界效应，为沿海海洋系统的养分管理策略提供了科学支持。

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引用次数: 0

Spatial richness patterns of large pelagic fishes in the Eastern Pacific Ocean 东太平洋大型中上层鱼类的空间丰富度格局

IF 3.2 3区环境科学与生态学 Q2 ENVIRONMENTAL SCIENCES

Marine environmental research

Pub Date : 2026-01-18 DOI: 10.1016/j.marenvres.2026.107860

Aura Buenfil-Ávila , Sofia Ortega-García , Héctor Villalobos , Javier Nori , Ulianov Jakes-Cota , Rodrigo Moncayo-Estrada , Gabriel Reygondeau

In the Eastern Pacific Ocean, the purse seine tuna fishery targets skipjack, yellowfin tuna, and bigeye tuna. However, bycatch of billfish is also common. Growing concerns about the rising bycatch levels and the capture of juveniles’ tunas underscore the need for spatial explicit management strategies. This study aims to model the geographic distributions of four tuna species (skipjack, yellowfin, bigeye, and black skipjack) and five billfish species (swordfish, sailfish, striped marlin, blue marlin, and black marlin) to understand how interannual variability shapes richness patterns of these species to inform spatial management efforts. Species distribution models were developed using MaxEnt based on environmental scenarios representing cold, neutral, and warm conditions from 2000 to 2020. A database of occurrences was compiled from Inter-American Tropical Tuna Commission's, while environmental variables were obtained from Copernicus Marine Service. Predicted distribution maps for each species were combined to generate species richness maps under different environmental scenarios. Areas of high species richness were identified near the Baja California peninsula, the southern Gulf of California, off the coast of Central America, and between the Ecuadorian coast and the Galapagos Islands, regions that overlap with known spawning and feeding grounds. Species richness patterns showed an interannual variability, expanding during warm periods and contracting during neutral and cold conditions, highlighting the need to adapt spatial management to environmental variability of oceans. These findings provide a basis for future spatial planning and conservation initiatives, highlighting the need for dynamic, flexible conservation strategies that can adapt to a changing ocean.

在东太平洋，围网金枪鱼渔业的目标是鲣鱼、黄鳍金枪鱼和大眼金枪鱼。然而，副捕获长嘴鱼也很常见。越来越多的人担心副渔获量的增加和金枪鱼幼鱼的捕获，这强调了制定明确的空间管理策略的必要性。本研究旨在模拟四种金枪鱼（鲣鱼、黄鳍鱼、大眼鱼和黑鲣）和五种长嘴鱼（旗鱼、旗鱼、条纹马林鱼、蓝马林鱼和黑马林鱼）的地理分布，以了解年际变化如何影响这些物种的丰富度模式，为空间管理工作提供信息。利用MaxEnt软件建立了2000 - 2020年寒、中、暖环境情景下的物种分布模型。美洲热带金枪鱼委员会编制了一个事件数据库，而哥白尼海洋服务处则获得了环境变量。将各物种预测分布图进行组合，生成不同环境情景下的物种丰富度分布图。物种丰富度高的地区被确定在加利福尼亚半岛附近，加利福尼亚湾南部，中美洲海岸，厄瓜多尔海岸和加拉帕戈斯群岛之间，这些地区与已知的产卵和觅食地重叠。物种丰富度格局呈现年际变化，在温暖期扩大，在中性和寒冷期缩小，突出了海洋空间管理适应环境变化的必要性。这些发现为未来的空间规划和保护举措提供了基础，强调了动态、灵活的保护策略的必要性，以适应不断变化的海洋。

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引用次数: 0

Nickel and cobalt disrupt the microbiome and metabolic function of the photosymbiotic sea slug Berghia stephanieae (Á. Valdés, 2005) 镍和钴会破坏光共生海蛞蝓（Berghia stephanieae）的微生物群和代谢功能（Á）。巴尔德斯,2005)

IF 3.2 3区环境科学与生态学 Q2 ENVIRONMENTAL SCIENCES

Marine environmental research

Pub Date : 2026-01-17 DOI: 10.1016/j.marenvres.2026.107845

Corinna Sickinger , Alicia Thiel , Julia Bornhorst , Gregor Christa , Angelika Preisfeld

The rapid global expansion of electromobility has increased demand for nickel and cobalt, which are key components in lithium-ion batteries. As a result, mining activities are intensifying, yet their ecological impact on marine ecosystems remains poorly understood. In this study, we examine the effects of nickel and cobalt on the microbiome composition and bacterial metabolic pathways of the marine photosymbiotic gastropod Berghia stephanieae. Preliminary toxicity tests showed concentration-dependent metal uptake, with behavioural stress responses such as lethargy, cessation of feeding, and shedding of cerata occurring at high concentrations (around 18 mg/L for nickel and cobalt). Microbiome analysis across three concentrations (1, 3, and 17 mg/L for nickel and cobalt) revealed significant changes in community composition and function. At 1 mg/L, the observed effects were concentration-dependent rather than metal-specific, as indicated by a decline in alpha diversity and a shift in community composition, characterised by a reduction in Mycoplasma sp. and an increase in Pseudofulvibacter and Endozoicomonas sp. At 3 mg/L, Shewanella spp. abundance increased and metal-specific effects emerged, with a strong downregulation of the metabolic pathways denitrification and lignin degradation for cobalt and an upregulation of sulfur oxidation for nickel. At 17 mg/L, many functional pathways were downregulated, aligning with observed host stress and pointing to a possible loss of functional redundancy. Overall, nickel and cobalt exposure led to distinct microbiome alterations, with intermediate levels eliciting the strongest metabolic response.

全球电动汽车的快速扩张增加了对镍和钴的需求，这是锂离子电池的关键成分。因此，采矿活动正在加剧，但其对海洋生态系统的生态影响仍然知之甚少。在这项研究中，我们研究了镍和钴对海洋光共生腹足动物伯格氏菌（Berghia stephanieae）微生物组组成和细菌代谢途径的影响。初步毒性试验显示，高浓度（镍和钴约为18毫克/升）的金属摄取与浓度有关，并伴有嗜睡、停止进食和脱落角状细胞等行为应激反应。三种浓度（镍和钴分别为1、3和17 mg/L）的微生物组分析显示，群落组成和功能发生了显著变化。当浓度为1 mg/L时，观察到的效应是浓度依赖性的，而不是金属特异性的，正如α多样性下降和群落组成的变化所表明的那样，其特征是支原体减少，假fulvibacter和Endozoicomonas sp.增加。当浓度为3 mg/L时，Shewanella sp.丰度增加，并出现金属特异性效应。对钴的反硝化和木质素降解代谢途径有强烈的下调，对镍的硫氧化有强烈的上调。在17 mg/L时，许多功能通路下调，与观察到的宿主应激一致，并指出可能失去功能冗余。总体而言，镍和钴暴露导致不同的微生物组改变，中等水平引起最强的代谢反应。

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引用次数: 0

Host species as key drivers of Symbiodiniaceae assemblages: Coral and free-living diversity in a Southwestern Atlantic oceanic island 寄主物种作为共生体科组合的关键驱动因素：西南大西洋岛屿上的珊瑚和自由生物多样性

IF 3.2 3区环境科学与生态学 Q2 ENVIRONMENTAL SCIENCES

Marine environmental research

Pub Date : 2026-01-17 DOI: 10.1016/j.marenvres.2025.107829

Camila Rodrigues Lima , Amana Guedes Garrido , Barbara Morim , Deborah Catharine de Assis Leite , Carla Zilberberg

Symbiodiniaceae is a diverse family of photosymbiont dinoflagellates known for forming mutualistic associations with reef-building corals and other marine invertebrates. This family comprises a diverse array of lineages with distinct physiological traits, enabling hosts to exhibit differential responses to environmental stressors. In addition to their endosymbiotic forms, Symbiodiniaceae also occur as free-living cells, potentially acting as environmental reservoirs that facilitate coral recolonization following bleaching events. This study provides the first comprehensive characterization of Symbiodiniaceae assemblages, examining both endosymbiotic and free-living assemblages across three reef sites using ITS2 rDNA next-generation sequencing at Fernando de Noronha archipelago (SWA). Sequences primarily belonged to the genera Symbiodinium, Breviolum and Cladocopium across all reef compartments. Both coral hosts and Symbiodiniaceae ITS 2 types exhibited generalist traits, with multiple associations observed. Endosymbiotic community structure was strongly host-driven, with most coral species dominated by a single ITS2 type, indicating high partner fidelity. Free-living assemblage (seawater and sediment) displayed greater diversity and a more even community composition compared to endosymbionts. A limited overlap was detected between coral-associated and environmental ITS2 sequences, suggesting restricted exchange but potential environmental reservoirs for dominant types. Our work reinforce that the corals hosts are the primary drivers of Symbiodiniaceae community structure in this oceanic island ecosystem. This research provide an essential baseline data for understanding coral–symbiont dynamics in the Southwestern Atlantic, particularly in face of global climate changes.

共生藻科是一个不同的光共生鞭毛藻家族，以与造礁珊瑚和其他海洋无脊椎动物形成共生关系而闻名。这个家族包括一系列具有不同生理特征的谱系，使寄主对环境压力表现出不同的反应。除了它们的内共生形式，共生菌科也以自由活细胞的形式出现，潜在地作为环境水库，促进珊瑚在白化事件后重新定植。本研究首次全面表征了共生体科（symbiodiiaceae）的组合，利用ITS2 rDNA新一代测序技术在费尔南多迪诺罗尼亚群岛（SWA）的三个珊瑚礁遗址中检测了内共生和自由生活的组合。所有礁室的序列主要属于共生属、Breviolum属和Cladocopium属。珊瑚寄主和共生体科ITS 2型寄主均表现出通才特征，存在多重关联。内共生群落结构强烈受宿主驱动，大多数珊瑚物种由单一ITS2型主导，表明伴侣保真度高。与内共生生物相比，自由生活组合（海水和沉积物）表现出更大的多样性和更均匀的群落组成。珊瑚相关ITS2序列和环境ITS2序列之间存在有限的重叠，表明交换有限，但优势类型具有潜在的环境储集层。我们的研究表明，珊瑚宿主是这个海洋岛屿生态系统共生科群落结构的主要驱动力。这项研究为了解西南大西洋珊瑚共生动态提供了重要的基线数据，特别是在面对全球气候变化的情况下。

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引用次数: 0

In-situ experimental evidence revealing how ocean warming promotes Aurelia coerulea polyps mediated by benthic ecosystem change 原位实验证据揭示海洋变暖如何促进底栖生态系统变化介导的蓝纹水螅。

IF 3.2 3区环境科学与生态学 Q2 ENVIRONMENTAL SCIENCES

Marine environmental research

Pub Date : 2026-01-17 DOI: 10.1016/j.marenvres.2026.107853

Wenxiao Zang , Yong Xu , Fang Zhang , Song Sun

Harmful jellyfish blooms are widely believed to be associated with global warming; however, direct in-situ evidence at an ecosystem level to explain bloom mechanisms is lacking. This study focused on Aurelia coerulea polyps and the local benthic ecosystem and applied field temperature manipulation to explore responses of polyps and benthic ecosystems to global warming, community changes, and polyp survival strategies. In our experiment, local heating (+1.5 °C and +3 °C) led to significant changes in benthic community structure (p < 0.001), a decline in biodiversity, and the proliferation of opportunistic dominant organisms. Aurelia coerulea polyps achieved remarkable expansion, with their coverage percentage reaching 79.73 % in the +3 °C group at the final sampling, significantly higher than the 53.30 % at ambient temperature. During the transition of the benthic ecosystem from stability to instability, jellyfish polyps expanded colonization by virtue of diversified asexual reproduction modes such as budding, longitudinal fission, stolonic budding, which were enhanced under warming, and their rapid responses to environmental change and strong adaptability to warming environments. Our study revealed direct effects on organisms and indirect effects mediated by ecosystems of global warming in the process of jellyfish polyp blooms and emphasized the importance of considering the comprehensive effect of global warming at the local benthic ecosystem level through in-situ experiments when explaining the proliferation of opportunistic and hazardous species with complex life cycles such as jellyfish.

有害的水母大量繁殖被广泛认为与全球变暖有关；然而，在生态系统水平上解释水华机制的直接原位证据缺乏。本研究以蓝纹水螅和当地底栖生态系统为研究对象，应用野外温度调控技术探讨了全球变暖、群落变化和水螅生存策略对水螅和底栖生态系统的响应。在我们的实验中，局部加热（+1.5°C和+3°C）导致底栖生物群落结构的显著变化(p

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引用次数: 0

Ecological consequences of seagrass decline on macrozoobenthic communities: a case study of a Zostera noltii meadow in Arcachon Bay, France 海草减少对大型底栖动物群落的生态影响：以法国Arcachon湾notii Zostera草甸为例

IF 3.2 3区环境科学与生态学 Q2 ENVIRONMENTAL SCIENCES

Marine environmental research

Pub Date : 2026-01-16 DOI: 10.1016/j.marenvres.2026.107857

Adeline Tauran, Xavier de Montaudouin, Danaé Dubrasquet, Lucille Zaragosi, Benoit Gouillieux, Nicolas Lavesque, Hugues Blanchet

Seagrasses form critical coastal habitats that are experiencing worldwide decline, often resulting in reduced abundance and diversity of associated macrofauna. This study focuses on Arcachon Bay (SW France), a coastal lagoon characterised by an extensive Zostera noltii meadow (40 km² in 2019) that has declined by 44 % since 1989. This work aimed to characterise benthic community responses to environmental changes, including seagrass loss, using uni and multivariate analyses of two broad-scale surveys (49 stations) conducted in 2002 and 2023, supplemented by a biennial survey at a single station over 22 years. Results reveal significantly different benthic communities in 2002 and 2023 associated with a significant loss in macrofauna densities, while diversity remained similar. Temporal β-diversity (β_SOR = 0.65) was primarily due to turnover (species replacement) rather than nestedness (species loss/gain). Five distinct benthic communities were identified, mainly influenced by seagrass biomass, elevation, distance to the ocean and sediment characteristics. The biennial surveys offered additional insights into the temporality of these changes at one station. The combined effect of these modifications and habitat fragmentation on the ecosystem functioning remains to be addressed more specifically.

海草是重要的沿海栖息地，在世界范围内正在减少，往往导致相关大型动物的丰度和多样性减少。这项研究的重点是Arcachon湾（法国西南部），这是一个沿海泻湖，其特征是大面积的Zostera noltii草甸（2019年为40平方公里），自1989年以来已经减少了44%。本研究旨在通过对2002年和2023年进行的两次大规模调查（49个站点）的单因素和多因素分析，并辅以22年来在单个站点进行的两年一次的调查，来描述底栖生物群落对环境变化（包括海草损失）的反应。结果表明，2002年和2023年底栖生物群落显著不同，大型动物密度显著下降，但多样性保持不变。时间β-多样性（βSOR = 0.65）主要是由于更替（物种替换）而不是巢性（物种损失/增加）。发现了5种不同的底栖生物群落，主要受海草生物量、海拔、与海洋的距离和沉积物特征的影响。两年一次的调查对一个站点的这些变化的时效性提供了更多的见解。这些变化和生境破碎化对生态系统功能的综合影响仍有待更具体地解决。

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引用次数: 0

Feeding selectivity of three fouling organisms and their relationship with phytoplankton community composition 三种污染生物的取食选择性及其与浮游植物群落组成的关系

IF 3.2 3区环境科学与生态学 Q2 ENVIRONMENTAL SCIENCES

Marine environmental research

Pub Date : 2026-01-16 DOI: 10.1016/j.marenvres.2026.107863

Shengxun Yao , Junxiang Lai , Maomi Zhao , Qiumei Jiang , Xiufen Liao , Zihan Pan , Congtao Sun

Marine biofouling poses a significant influence on marine engineering equipment, and phytoplankton is the primary food source for fouling organisms, therefore, we investigated the feeding selectivity of three fouling organisms and their relationship with phytoplankton community composition using the 18S rDNA high-throughput sequencing technology. The results show that Bacillariophyta, Chlorophyta phyla, and Chaetoceros genus are dominant both in the guts of fouling organism and seawater. SourceTracker analysis reveal that fouling organisms' gut phytoplankton are largely derived from seawater and network analysis show predominantly positive co-occurrence pattern particularly within the guts of fouling organisms. Selectivity indices indicate all the fouling organisms preferential feeding on Chlorophyta and chaetoceros. Spearman correlation analysis reveal that dissolved oxygen (DO), salinity, and temperature are significantly correlated with most dominant phytoplankton genera in the gut of fouling organisms and seawater. The research, therefore, will highlight the fouling organisms have a selective regulatory effect on phytoplankton, and the phytoplankton communities that promote the growth of fouling organisms are the dominant species in the gut.

海洋生物污染对海洋工程设备有重要影响，而浮游植物是污染生物的主要食物来源，因此，我们利用18S rDNA高通量测序技术研究了三种污染生物的取食选择性及其与浮游植物群落组成的关系。结果表明：在污染生物的肠道和海水中，硅藻门、绿藻门和毛藻门均占优势；SourceTracker分析显示污染生物肠道浮游植物主要来源于海水，网络分析显示污染生物肠道内浮游植物主要为正共生模式。选择性指数表明，所有污染生物优先捕食绿藻和毛藻。Spearman相关分析表明，溶解氧（DO）、盐度和温度与污染生物肠道和海水中大多数优势浮游植物属呈显著相关。因此，本研究将强调污垢生物对浮游植物具有选择性调节作用，而促进污垢生物生长的浮游植物群落是肠道中的优势物种。

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引用次数: 0

Transformation of particulate matter while sinking through the oxygen minimum zone of the Eastern Arabian Sea 通过东阿拉伯海最低氧区下沉时颗粒物的转化。

IF 3.2 3区环境科学与生态学 Q2 ENVIRONMENTAL SCIENCES

Marine environmental research

Pub Date : 2026-01-16 DOI: 10.1016/j.marenvres.2026.107858

Siby Kurian, Apsara Vijayan, Damodar M. Shenoy, Suhas Shetye, Supriya Karapurkar, Albertina Dias, Anand Methar, Aninda Mazumdar, Aditya Peketi, Rakhee Khandeparker

The degradation of particulate organic matter in the ocean plays a critical role in regulating the marine carbon cycle and sustaining oxygen minimum zones. In this study, suspended particulate matter from two stations in the eastern Arabian Sea, encompassing both oxic and suboxic water columns, was studied to investigate the transformation of particulate matter during vertical transport. Scanning electron microscopy revealed the presence of diverse planktonic assemblages with a noticeable decline in abundance at greater depths. Particulate organic carbon (POC) and particulate nitrogen (PN) concentrations decreased sharply within the upper 60 m, indicating rapid degradation of labile organic matter in the euphotic zone. The POC/PN ratio increased with depth, suggesting preferential nitrogen loss during remineralisation. δ¹⁵N values ranged from +2.7 ‰ to +6.4 ‰, with enriched signatures in surface and suboxic layers, while δ¹³C values became progressively depleted with depth (up to −25.6 ‰), reflecting the loss of isotopically heavier compounds and the dominance of lighter, more refractory material. Phytoplankton marker pigments were abundant in the upper water column, while degradation products were prevalent in suboxic waters. Fatty acid methyl ester profiles were dominated by palmitic acid, followed by stearic acid, indicating a predominance of diatoms and dinoflagellates. Sterol analysis identified cholesterol, brassicasterol, stigmasterol, and β-sitosterol, with depth-dependent variations in their concentrations. Despite differences in depth and dissolved oxygen profiles between the two stations, the study consistently demonstrated substantial degradation of organic matter within the upper 60 m oxic water column and highlighted the differential preservation efficiencies of various biogeochemical markers.

海洋颗粒物有机物的降解在调节海洋碳循环和维持最低氧区中起着至关重要的作用。本研究以阿拉伯海东部两个站的悬浮颗粒物为研究对象，研究了悬浮颗粒物在垂直输送过程中的转化。扫描电子显微镜显示了不同浮游生物组合的存在，在更深的地方丰度明显下降。颗粒有机碳（POC）和颗粒氮（PN）浓度在60 m范围内急剧下降，表明绿化带内活性有机物降解迅速。POC/PN比随深度增加而增加，表明再矿化过程中氮的优先损失。δ15N值在+2.7‰~ +6.4‰之间，在表层和亚氧层表现出富集特征，而δ13C值随着深度的增加逐渐减弱（最大可达-25.6‰），反映了同位素较重的化合物的损失和较轻的难熔物质的优势。浮游植物标志色素在上层水体中丰富，而降解产物在亚氧水体中普遍存在。脂肪酸甲酯谱以棕榈酸为主，其次是硬脂酸，表明硅藻和鞭毛藻占优势。甾醇分析鉴定出胆固醇、油菜甾醇、豆甾醇和β-谷甾醇，其浓度随深度变化而变化。尽管两个站点之间的深度和溶解氧分布存在差异，但研究一致表明，在60 m以上的氧化水柱中有机物存在大量降解，并突出了各种生物地球化学标记物的保存效率差异。

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引用次数: 0

Trends in biodiversity research in Brazilian marine protected areas 巴西海洋保护区生物多样性研究趋势

IF 3.2 3区环境科学与生态学 Q2 ENVIRONMENTAL SCIENCES

Marine environmental research

Pub Date : 2026-01-16 DOI: 10.1016/j.marenvres.2026.107864

Vinicius J. Giglio , Carine O. Fogliarini , Mariana G. Bender , Carlos E.L. Ferreira

Marine protected areas (MPAs) are the main conservation tool for safeguarding biodiversity and ecological processes. However, their planning and effectiveness depend on a robust understanding of biodiversity patterns. We conducted a systematic review of the literature to investigate trends in biodiversity research within Brazilian MPAs. We evaluated the taxonomic groups, diversity facets (taxonomic, functional and phylogenetic), sampling approaches and geographic distribution of studies. Of the 191 articles reviewed, 71% investigated a single diversity facet and 29%% considered both taxonomic and functional facets. Despite an increase in research over recent decades, the literature remains taxonomically and geographically biased. Most studies focused on fishes (58%) and taxonomic diversity (52%), while 20% addressed functional diversity, and phylogenetic diversity was virtually absent. Vertebrates were overrepresented, and studies were concentrated in fully protected MPAs and in Southeastern, Eastern, and Northeastern ecoregions. Most articles (93%) generated primary data, mainly through diver-based and imaging surveys. The limited integration across diversity facets may hinder a comprehensive understanding of ecological processes and effective conservation planning. We identify knowledge gaps and recommend expanding research efforts to underrepresented regions, taxa, and diversity facets. We encourage basic diversity research through species inventories for poorly known taxa and MPAs. Incorporating diversity facets will contribute to improving the ecological representativeness and resilience of Brazilian MPAs.

海洋保护区是保护生物多样性和生态过程的主要保护工具。然而，它们的规划和有效性取决于对生物多样性模式的充分理解。我们对文献进行了系统回顾，以调查巴西海洋保护区生物多样性研究的趋势。我们评估了分类类群、多样性方面（分类、功能和系统发育）、抽样方法和研究的地理分布。在所回顾的191篇文献中，71%研究了单一多样性方面，29%研究了分类学和功能方面。尽管近几十年来的研究有所增加，但文献在分类学和地理上仍然存在偏见。大多数研究集中在鱼类（58%）和分类多样性（52%）上，而20%的研究集中在功能多样性上，系统发育多样性几乎缺失。脊椎动物的比例过高，研究集中在完全保护的海洋保护区和东南部、东部和东北部的生态区域。大多数文章（93%）主要通过潜水员和成像调查生成原始数据。多样性方面的有限整合可能会阻碍对生态过程的全面理解和有效的保护规划。我们发现知识差距，并建议将研究工作扩大到代表性不足的地区、分类群和多样性方面。我们鼓励通过对鲜为人知的分类群和海洋保护区进行物种清查来进行基本的多样性研究。纳入多样性方面将有助于提高巴西海洋保护区的生态代表性和恢复力。

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引用次数: 0

Quantifying the effect of biomass magnitude on apparent methylmercury toxicity in marine phytoplankton 量化生物量量级对海洋浮游植物甲基汞表观毒性的影响

IF 3.2 3区环境科学与生态学 Q2 ENVIRONMENTAL SCIENCES

Marine environmental research

Pub Date : 2026-01-16 DOI: 10.1016/j.marenvres.2026.107861

Owhonda Chikeru Ihunwo, Edward A. Laws

Methylmercury (MeHg) is a potent neurotoxin whose ecological impacts begin at the base of marine food webs, yet laboratory toxicity assays often rely on phytoplankton biomass levels far exceeding those found in natural waters. This discrepancy obscures true per-cell sensitivity and complicates cross-species comparisons. Here, we quantify the influence of initial biomass on apparent MeHg toxicity across five ecologically and taxonomically diverse marine phytoplankton—Thalassiosira pseudonana, Cricosphaera carterae, Emiliania huxleyi, Synechococcus elongatus, and Phaeodactylum tricornutum. Dose–response experiments were conducted across a gradient of initial optical densities (OD₇₅₀), and EC₅₀ values were estimated using nonlinear regression. Log₁₀-transformed EC₅₀ values exhibited strong linear relationships with OD₇₅₀ for most species, demonstrating a consistent biomass buffering effect in which higher cell densities reduce apparent MeHg toxicity. Extrapolation of regression models to OD = 0 yielded intrinsic, biomass-normalized EC₅₀ values that converged more tightly across taxa than raw EC₅₀ measurements, revealing a shared physiological sensitivity range once biomass artifacts were removed. Cricosphaera carterae was the most sensitive species (EC₅₀ = 0.0015 μg/L), while Synechococcus elongatus was the most tolerant (EC₅₀ = 43.86 μg/L). These biomass-adjusted EC₅₀ values were used to construct a species sensitivity distribution (SSD), from which an HC₅ of 2.25 x 10⁻³ μg/L was estimated. Following the EPA acute-criteria relationship (FAV = 2 × HC₅), a Final Acute Value (FAV) of 4.50 x 10⁻³ μg/L was derived. These findings demonstrate that biomass strongly modulates apparent MeHg toxicity and that biomass-adjusted EC₅₀ values serve as useful upper-bound estimates of per-cell sensitivity. This framework provides a reproducible method for normalizing toxicity data across taxa and improves the interpretation of contaminant sensitivity under low-biomass conditions without directly predicting ecological risk in situ.

甲基汞（MeHg）是一种强效的神经毒素，其生态影响始于海洋食物网的基础，但实验室毒性分析往往依赖于远远超过自然水域的浮游植物生物量水平。这种差异模糊了真实的单个细胞敏感性，并使跨物种比较变得复杂。在这里，我们量化了初始生物量对五种生态和分类上都不同的海洋浮游植物——假海藻、环状藻、赫克斯利Emiliania huxleyi、长聚球菌（Synechococcus elongatus）和三角褐指藻——甲基汞表观毒性的影响。在初始光密度梯度（OD750）上进行剂量响应实验，并使用非线性回归估计EC50值。log10转化后的EC50值与大多数物种的OD750呈强烈的线性关系，表明了一致的生物量缓冲效应，即较高的细胞密度降低了甲基汞的表观毒性。将回归模型外推到OD = 0，得到的内在的、生物量归一化的EC50值比原始的EC50测量值更紧密地收敛于不同的分类群，揭示了在去除生物量人工影响后共享的生理敏感性范围。对该菌最敏感的菌种是圆环虫（crosphaera carterae）（EC50 = 0.0015 μg/L），对该菌最耐受的菌种是长聚球菌（Synechococcus elongatus）（EC50 = 43.86 μg/L）。利用这些生物量调整后的EC50值构建物种敏感性分布（SSD），据此估计HC5为2.25 × 10−3 μg/L。根据EPA急性标准关系（FAV = 2 × HC5），得出最终急性值（FAV）为4.50 x 10−3 μg/L。这些发现表明，生物量强烈调节甲基汞的表观毒性，生物量调整的EC50值可以作为每个细胞敏感性的有用上限估计。该框架提供了一种可重复的方法来标准化跨分类群的毒性数据，并改善了低生物量条件下污染物敏感性的解释，而无需直接预测原位生态风险。

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