Microbe, climate change and marine environment: Linking trends and research hotspots
微生物、气候变化和海洋环境:连接趋势和研究热点

https://doi.org/10.1016/j.marenvres.2023.106015Get rights and content 获取权利和内容

Highlights 亮点

  • A comprehensive scientometric analysis has been conducted to evaluate the quantitative relationship between microbial communities, climate change, and the marine ecosystem. This assessment employs advanced statistical techniques to analyze the existing body of literature and identify significant patterns and trends.
    我们进行了全面的科学计量分析,以评估微生物群落、气候变化和海洋生态系统之间的定量关系。该评估采用先进的统计技术来分析现有文献并确定重要的模式和趋势。
  • The anticipated key research focus in the near future is the “coral microbiome,” with “human health” being a close second. This projection emphasizes the growing importance of understanding the role of microorganisms in coral reef ecosystems and their potential implications for human well-being.
    预计近期的重点研究重点是“珊瑚微生物组”,“人类健康”紧随其后。该预测强调了解微生物在珊瑚礁生态系统中的作用及其对人类福祉的潜在影响日益重要。
  • Among the most impactful keywords identified within the subject matter are “microbial diversity” and “ocean acidification.” These terms highlight the critical need for continued investigation into the complex interplay between marine microbial communities and the effects of climate-induced oceanic changes, such as increased acidity levels.
    该主题中确定的最有影响力的关键词是“微生物多样性”和“海洋酸化”。这些术语强调了继续研究海洋微生物群落与气候引起的海洋变化(例如酸度水平升高)的影响之间复杂的相互作用的迫切需要。
  • The study also underscores the importance of robust international collaboration in advancing our understanding of this interdisciplinary field.
    该研究还强调了强有力的国际合作对于增进我们对这一跨学科领域的理解的重要性。

Abstract 抽象的

Microbes, or microorganisms, have been the foundation of the biosphere for over 3 billion years and have played an essential role in shaping our planet. The available knowledge on the topic of microbes associated with climate change has the potential to reshape upcoming research trends globally. As climate change impacts the ocean or marine ecosystem, the responses of these “unseen life” will heavily influence the achievement of a sustainable evolutionary environment. The present study aims to identify microbial-related research under changing climate within the marine environment through the mapping of visualized graphs of the available literature. We used scientometric methods to retrieve documents from the Web of Science platform in the Core Collection (WOSCC) database, analyzing a total of 2767 documents based on scientometric indicators. Our findings show that this research area is growing exponentially, with the most influential keywords being “microbial diversity,” “bacteria,” and “ocean acidification,” and the most cited being “microorganism” and “diversity.” The identification of influential clusters in the field of marine science provides insight into the hot spots and frontiers of research in this area. Prominent clusters include “coral microbiome,” “hypoxic zone,” “novel Thermoplasmatota clade,” “marine dinoflagellate bloom,” and “human health.” Analyzing emerging trends and transformative changes in this field can inform the creation of special issues or research topics in selected journals, thus increasing visibility and engagement among the scientific community.
超过 30 亿年来,微生物一直是生物圈的基础,在塑造我们的星球方面发挥着重要作用。关于与气候变化相关的微生物主题的现有知识有可能重塑全球即将到来的研究趋势。随着气候变化影响海洋或海洋生态系统,这些“看不见的生命”的反应将严重影响可持续进化环境的实现。本研究旨在通过绘制现有文献的可视化图表来确定海洋环境中气候变化下与微生物相关的研究。我们使用科学计量方法从核心合集(WOSCC)数据库中的Web of Science平台检索文献,根据科学计量指标分析了总共2767篇文献。我们的研究结果表明,这一研究领域正在呈指数级增长,最有影响力的关键词是“微生物多样性”、“细菌”和“海洋酸化”,被引用最多的是“微生物”和“多样性”。识别海洋科学领域有影响力的集群,深入了解该领域的研究热点和前沿。突出的集群包括“珊瑚微生物群”、“缺氧区”、“新型热原体进化枝”、“海洋甲藻华”和“人类健康”。分析该领域的新兴趋势和变革可以为选定期刊中特刊或研究主题的创建提供信息,从而提高科学界的知名度和参与度。

Keywords 关键词

Microbial community
Carbon
Sediment
Phytoplankton
Surface water
Dynamic
Temperature
Antibiotic resistance gene
Stress tolerance
Organic matter

微生物群落
沉淀
浮游植物
地表水
动态的
温度
抗生素抗性基因
抗压能力
有机物

1. Introduction 一、简介

Microorganisms, including bacteria, fungi, protozoa, and viruses, constitute a diverse group of microscopic life forms that collectively account for approximately 60% of the Earth's biomass (Fraser et al., 2000; FAO, 2023). While some microbes can be harmful, many play essential roles in maintaining environmental balance and supporting various industries. These ubiquitous entities, which also encompass yeasts, molds, and parasites, are found in myriad natural environments worldwide, such as soil, water, the atmosphere, and on the surfaces of plants, animals, and other living organisms (Donlan, 2002). Their diverse functions have been harnessed for advancements in sectors like agriculture (Berg, 2009; Diwan et al., 2022; Canales et al., 2022), water quality and waste management (Aracic et al., 2015; Lugo et al., 2021; Ling et al., 2023), and medicine and healthcare (Cruz-López et al., 2023; Mohan et al., 2023; Zhang et al., 2023).They are diverse and tolerant in extremely hotter and colder temperatures (Rothschild and Mancinelli, 2001; Alsharif et al., 2020; Sarma et al., 2023). Therefore, any study that identifies the relationship between microbes and the current changing climate could provide a better understanding of how these organisms react in the future. Additionally, it could attract further research collaboration or development of any special topics in the field (Cavicchioli et al., 2019).
微生物,包括细菌、真菌、原生动物和病毒,构成了多种微观生命形式,总共约占地球生物量的 60%( Fraser 等,2000FAO,2023 )。虽然有些微生物可能有害,但许多微生物在维持环境平衡和支持各个行业方面发挥着重要作用。这些无处不在的实体,还包括酵母、霉菌和寄生虫,存在于世界各地无数的自然环境中,例如土壤、水、大气以及植物、动物和其他生物体的表面 Donlan,2002 )。它们的多样化功能已被用于农业 Berg,2009Diwan 等人,2022Canales 等人,2022 )、水质和废物管理 Aracic 等人,2015Lugo 等人, 2021Ling 等人,2023 ),以及医学和医疗保健( Cruz-López 等人,2023Mohan 等人,2023Zhang 等人,2023 )。它们具有多样性,能够耐受极热和极冷的温度( Rothschild 和 Mancinelli,2001Alsharif 等,2020Sarma 等,2023 )。因此,任何确定微生物与当前气候变化之间关系的研究都可以更好地了解这些生物体在未来如何反应。此外,它还可以吸引该领域任何特殊主题的进一步研究合作或开发( Cavicchioli 等人,2019 )。
IPCC (Intergovernmental Panel on Climate Change), defines climate change as a change to the state of the climate, such as global warming (i.e., temperature), trends in precipitation (i.e., rainfall), or other human-caused environmental factors, for an extended period, typically decades or longer (IPCC, 2018). Based on the current 2022 report of the Lancet Countdown, climate change-related issues such as extreme weather events such as floods, wildfires, heatwaves or extreme heat have impacted food security, health, and economy for most of the countries in the world (Romanello et al., 2023). Interestingly, climate change-related studies have attracted various researchers for various reasons, such as (i) funding availability, especially in the African region (Overland et al., 2022), (ii) citation attraction or also known as the “Matthew Effect” (Haunschild et al., 2016) and (iii) for sustainable horizons (Moss et al., 2010; Shrivastava et al., 2020). Additionally, any related research on climate change could benefit further policymaking and funding acquisitions within the limited resources in the future.
IPCC(政府间气候变化专门委员会)将气候变化定义为气候状态的变化,例如全球变暖(即温度)、降水趋势(即降雨)或其他人为环境因素,较长一段时间,通常是数十年或更长时间( IPCC,2018 )。根据《柳叶刀倒计时》当前的 2022 年报告,洪水、野火、热浪或极端高温等极端天气事件等气候变化相关问题已经影响了世界上大多数国家的粮食安全、健康和经济(罗马内洛等人,2023 )。有趣的是,气候变化相关研究由于各种原因吸引了各种研究人员,例如(i)资金可用性,特别是在非洲地区( Overland et al., 2022 ),(ii)引用吸引力或也称为“马太效应” ”( Haunschild 等人,2016 年)和(iii)可持续发展前景( Moss 等人,2010 年Shrivastava 等人,2020 年)。此外,任何有关气候变化的相关研究都可能有利于未来在有限资源内的进一步决策和资金收购。
Considering the intricacy of the marine food web, the dynamics of microbial communities represent a crucial indicator of the overall health and status of the ocean. Microbial assemblages respond to fluctuations in numerous environmental factors, such as light, temperature, oxygen, nutrients, metabolites, and xenobiotics, which make them ideal candidates for biosensing and bioindication of ecological changes, both short- and long-term in nature. This makes microbial communities a valuable tool for assessing the ocean's state and monitoring environmental impacts on marine ecosystems (Buttigieg et al., 2018).
考虑到海洋食物网的复杂性,微生物群落的动态代表了海洋整体健康和状况的重要指标。微生物组合对光、温度、氧气、营养物、代谢物和外源物质等众多环境因素的波动做出反应,这使得它们成为短期和长期生态变化的生物传感和生物指示的理想候选者。这使得微生物群落成为评估海洋状况和监测环境对海洋生态系统影响的宝贵工具( Buttigieg 等,2018 )。
The marine environment, particularly the ocean, plays a critical role in regulating the Earth's climate by absorbing excess heat energy (Alosairi et al., 2020; Miyama et al., 2021; Yao and Wang, 2021), accounting for approximately 90% of the total heat uptake (Gleckler et al., 2016). This process contributes to the rise in sea surface temperatures and the overall phenomenon of ocean warming. The increase in sea surface temperatures and ocean warming directly or indirectly contribute to alterations in various life forms within the marine ecosystem, such as coral reefs (Thirukanthan et al., 2023), mangrove forests (Segaran et al., 2023), seagrass (Unsworth et al., 2019), seaweed (Harley et al., 2012), pelagic fish (Cheung et al., 2010), and bottom shellfish (Kroeker et al., 2013). These changes can have profound implications for the structure, function, and resilience of these ecosystems. Marine microbes such as archaea, protists, and fungi are often called “engines” of the marine ecosystem because they play a vital role in providing food and nutrients to marine organisms (Worden et al., 2015). These interactions and any relationship between microbes, climate change, and marine ecosystems can be identified through scientometric-based analysis.
海洋环境,特别是海洋,通过吸收多余的热能,对调节地球气候起着至关重要的作用( Alosairi et al., 2020 ; Miyama et al., 2021 ; Yao and Wang, 2021 ),约占地球总量的90%。总热量吸收( Gleckler 等人,2016 )。这一过程导致海面温度上升和海洋变暖的整体现象。海面温度升高和海洋变暖直接或间接导致海洋生态系统内各种生命形式的改变,例如珊瑚礁( Thirukanthan等,2023 )、红树林 Segaran等,2023 )、海草 Unsworth 等人,2019 )、海藻( Harley 等人,2012 )、中上层鱼类 Cheung 等人,2010 )和底层贝类( Kroeker 等人,2013 )。这些变化可能会对这些生态系统的结构、功能和恢复力产生深远的影响。 古生菌原生生物和真菌等海洋微生物通常被称为海洋生态系统的“引擎”,因为它们在为海洋生物提供食物和营养物质方面发挥着至关重要的作用( Worden et al., 2015 )。微生物、气候变化和海洋生态系统之间的这些相互作用和任何关系都可以通过基于科学计量的分析来确定。
Scientometrics is commonly defined by researchers and scholars as a quantitative study of science (Abramo, 2018); a simpler explanation from the present study is (scien: sciences) (to: towards) (metrics: something that can be measured). These techniques have gained prominence due to their ability to identify the evolution, management, and collaboration of any selected scientific research and organization. As the availability of easy-to-use software (e.g., VOSviewer, CiteSpace, Histcite) and the number of citation databases (e.g., Scopus, Web of Science, PubMed, China National Knowledge Infrastructure Database, Chinese Social Sciences Citation Index, Dimensions) continue to grow, it is anticipated that the prevalence of this type of review increases in the coming years (Chen, 2006; Perianes-Rodriguez et al., 2016). Scientometric analysis, applied across various fields, efficiently measures trends and metrics of selected topics. These methods concisely represent targeted subjects through visualized graphs, regardless of the size of the published literature (Chen, 2006).
科学计量学通常被研究人员和学者定义为科学的定量研究( Abramo,2018 );本研究的一个更简单的解释是(scien:科学)(to:朝着)(metrics:可以测量的东西)。这些技术因其识别任何选定科学研究和组织的演变、管理和协作的能力而受到关注。由于易于使用的软件(例如 VOSviewer、CiteSpace、Histcite)和引文数据库(例如 Scopus、Web of Science、PubMed、中国国家知识基础设施数据库、中国社会科学引文索引、Dimensions)的数量继续增长,预计此类审查的流行度在未来几年将会增加( Chen,2006Perianes-Rodriguez 等人,2016 )。科学计量分析应用于各个领域,可以有效地衡量所选主题的趋势和指标。这些方法通过可视化图表简洁地表示目标主题,无论发表的文献有多少( Chen,2006 )。
Hence, this study aimed to examine the current trends and hotspots of knowledge (i.e., the marine microbes under the changing environment). Specifically, the study will visualize the (i) evolution of publication (publication number, journals, open access & WOS categories), (ii) Highly cited article based on the WOSCC database, (iii) Author networks collaboration, networks of institution and countries, (iv) keywords burstiness and cluster (v) cluster analysis of the co-citation (i.e., references), and (vi) future hotspot of the topic.
因此,本研究旨在探讨当前的趋势和知识热点(即变化环境下的海洋微生物)。具体来说,该研究将可视化 (i) 出版物的演变(出版物数量、期刊、开放获取和 WOS 类别),(ii) 基于 WOSCC 数据库的高被引文章,(iii) 作者网络协作、机构和国家网络,(iv)关键词突发性和聚类(v)同被引(即参考文献)的聚类分析,以及(vi)该主题的未来热点。
The results provide new evidence and a knowledge bank of microbial drivers under a rapidly changing landscape within the marine environment. Additionally, the present study also contributes to current literature that might increase our understanding of how scientific output develops, connects, and performs.
研究结果为海洋环境快速变化的景观下的微生物驱动因素提供了新的证据和知识库。此外,本研究还对当前的文献做出了贡献,可能会增加我们对科学成果如何发展、联系和执行的理解。

2. Materials and methods 2 材料与方法

2.1. PRISMA adaptation 2.1. PRISMA 适配

Many scientometric reviews (also known as mapping reviews) synthesize previous literature and adapt the PRISMA guidelines for designing and reporting search strategies, data sources, extraction, and related analyses (Moher et al., 2009; Page et al., 2021). These reviews provide clear evidence on specific topics by identifying articles in scientific databases, screening them based on eligibility criteria, and analyzing them using appropriate software. To retrieve the metadata and cited references for the present study, the Web of Knowledge platform of the Core Collection database was used and searched on 20th February 2023. Terms were searched for their synonyms and separated from each other with the Boolean operator of “OR” and asterisks were included to allow for variation in terminology. There are about forty-two keywords or synonyms on “climate change”, twelve on “marine” related keywords, and two main keywords of “microbe” were tagged as “Topic” fields in the WOSCC searching activities. We excluded all the publications that are not in the form of original research articles and restricted only to the English language-based literature. We also excluded all the publications with the maximum year being before 31st December 2022, with no restriction on the minimum year. Fig. 1 shows the flowchart based on the PRISMA guidelines for the present study.
Fig. 1
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Fig. 1. Flowchart of the PRISMA for the present study.
图1 .本研究的 PRISMA 流程图。

2.2. Scientometric analysis
2.2.科学计量分析

Full records and cited references on the details of the publication were then exported from the WOS as a text file format. These files will be uploaded to the bibliometric-based software of CiteSpace (Version 6.1.6R Advance for Windows and incorporated with Java application). CiteSpace is a visual analytic software for analyzing current research trends and patterns in the scientific literature of any field of study. CiteSpace, developed by Chaomei Chen, is a versatile program that facilitates the analysis of various node types, such as author, institution, and country (collaboration network), keywords (co-occurrence network), category (co-occurrence network), and references (co-citation network), among others (Chen, 2006).
然后,将出版物详细信息的完整记录和引用的参考文献以文本文件格式从 WOS 导出。这些文件将上传到基于文献计量的CiteSpace软件(Windows版本6.1.6R Advance,并与Java应用程序合并)。 CiteSpace 是一款可视化分析软件,用于分析任何研究领域的科学文献中的当前研究趋势和模式。 CiteSpace是由Chaomei Chen开发的一款多功能程序,可以方便地分析各种节点类型,例如作者、机构和国家(协作网络)、关键词(共现网络)、类别(共现网络)和参考文献(同被引网络)等( Chen,2006 )。
We employed specific parameters for the analysis, including the g-index and pathfinder pruning criteria. The g-index, with a k factors scale of 25, was chosen based on its ability to maintain a balance between the scope and specificity of the analysis by incorporating only impactful publications. Concurrently, the pathfinder pruning criteria were utilized to identify and highlight crucial connections between publications, effectively reducing network complexity (Schvaneveldt, 1990; Egghe, 2006).
我们采用特定参数进行分析,包括 g 指数和探路者修剪标准。选择k因子为 25 的 g 指数是因为它能够通过仅纳入有影响力的出版物来保持分析范围和特异性之间的平衡。同时,利用探路者修剪标准来识别和突出出版物之间的关键联系,有效降低网络复杂性( Schvaneveldt,1990Eghe,2006 )。
The methods employed in this study include cluster analysis, timeline co-citation analysis, and keyword distribution analysis. Cluster analysis, utilizing Latent Semantic Indexing (LSI), Log-Likelihood Ratio (LLR), and Mutual Information (MI) algorithms, organizes research data into distinct units based on term correlations, revealing key research themes, trends, and connections. The homogeneity of a cluster is quantified using the mean silhouette index, ranging from −1 to 1, with higher values indicating greater similarity among cluster members (Zhong et al., 2019).
本研究采用的方法包括聚类分析、时间线共被引分析和关键词分布分析。聚类分析利用潜在语义索引 (LSI)、对数似然比 (LLR) 和互信息 (MI) 算法,根据术语相关性将研究数据组织成不同的单元,揭示关键研究主题、趋势和联系。簇的同质性使用平均轮廓指数进行量化,范围从-1到1,值越高表明簇成员之间的相似性越高( Zhong et al., 2019 )。
Timeline co-citation analysis examines relationships between co-cited literature across specific time periods, identifying patterns of scientific collaboration, knowledge distribution, recent developments, and potential future research directions (Chen et al., 2022). Finally, keyword distribution analysis identifies research trends over time by examining keyword co-occurrence in research articles, highlighting areas of research receiving significant attention and revealing understudied or overlooked areas that may warrant further investigation (Radhakrishnan et al., 2017; Zou et al., 2022).
时间线同被引分析检查特定时间段内同被引用文献之间的关系,确定科学合作模式、知识分布、最新发展和未来潜在的研究方向( Chen 等,2022 )。最后,关键词分布分析通过检查研究文章中关键词的共现情况来确定一段时间内的研究趋势,突出显示受到高度关注的研究领域,并揭示可能需要进一步研究的未充分研究或被忽视的领域( Radhakrishnan 等,2017Zou 等,2017)。 ,2022 )。

3. Results 3. 结果

3.1. Evolution of publication (publication number, journals, open access & WOS categories)
3.1.出版物的演变(出版物数量、期刊、开放获取和 WOS 类别)

A total of 2767 relevant literature sources were retrieved from the Web of Science Core Collection (WOSCC) database, focusing on the association between microbes and climate change between the years 1986 and 2022. The first article related to this subject matter was published in 1986 in the journal “Paleoceanography” (now known as “Paleoceanography and Paleoclimatology”), titled “Anoxic events, productivity rhythms, and the orbital signature in a Mid-Cretaceous deep-sea sequence from central Italy” by Herbert et al. (1986). Despite the publication of this seminal work, no subsequent studies focused on microbes in the marine environment associated with climate change were found in the WOSCC database until 1991. From the early 2010s to the present day, a total of 2291 publications were recorded, representing a fivefold increase compared to the preceding 24-year period (1986–2010) (Fig. 2a). The majority of publications are featured in high-quality journals within Quartiles 1 and 2 of WOS, with the top 10 publications listed in Fig. 2b. Notably, the journals “Frontiers in Microbiology” (n = 126) and “Science of the Total Environment” (n = 84) are among the most dominant outlets for publications in this field. A significant proportion (53.42%) of publications are freely available on the internet, whereas 46.58% did not disclose data regarding open access availability in the WOSCC database (Fig. 2c). WoS Categories were utilized to identify specific subject areas, with Environmental Sciences being the most commonly recognized field, followed by Microbiology, Ecology, and Marine Freshwater Biology (Fig. 2d).
从Web of Science核心合集(WOSCC)数据库中总共检索到2767篇相关文献来源,重点关注1986年至2022年间微生物与气候变化之间的关联。第一篇与该主题相关的文章发表于1986年《古海洋学》杂志(现称为《古海洋学和古气候学》),题为《意大利中部白垩纪中期深海序列中的缺氧事件、生产力节律和轨道特征》,作者: Herbert 等人。 (1986) 。尽管发表了这项开创性的工作,但直到 1991 年才在 WOSCC 数据库中发现针对与气候变化相关的海洋环境中的微生物的后续研究。从 2010 年代初到现在,总共记录了 2291 篇出版物,代表了与之前 24 年期间(1986-2010)相比增加了五倍(图 2a )。大多数出版物发表在 WOS 第 1 和第 2 四分位数内的高质量期刊中,排名前 10 的出版物如图 2b所示。值得注意的是,“微生物学前沿”(n = 126)和“总体环境科学”(n = 84)期刊是该领域最主要的出版物渠道之一。很大一部分(53.42%)的出版物可以在互联网上免费获取,而 46.58% 的出版物没有披露 WOSCC 数据库中有关开放获取可用性的数据(图 2c )。 WoS 类别用于识别特定的学科领域,其中环境科学是最常被认可的领域,其次是微生物学、生态学和海洋淡水生物学图 2d )。
Fig. 2
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Fig. 2. (a) Distribution of microbial research articles and citations associated with climate change from 1986 to 2022; (b) Major journals within the topic; (c) Open access documents; (d) Web of Science Core Collection categories. *Q1 is based on the JCR, 2021, **PNAS: Proceedings of the National Academy of Sciences of the United States of America.
图2 . (a) 1986 年至 2022 年与气候变化相关的微生物研究文章和引文的分布情况; (b) 该主题内的主要期刊; (c) 开放获取文件; (d) Web of Science 核心合集类别。 *第一季度基于JCR,2021 年,**PNAS:美国国家科学院院刊。

3.2. Highly cited article based on the WOSCC database
3.2.基于 WOSCC 数据库的高被引文章

The results generated from the Web of Science Core Collection (WOSCC) are also featured in their citation reports, which list the top 50 cited articles in the field (Supplementary Material 1). Nearly half of the top 20 articles on the topic are published in either Nature or Science (9/20). The top 10 globally cited articles are related to each other (Table 1), with the most highly cited being the study by Raghoebarsing et al. (2006), which has garnered 891 citations in the WOSCC database and 1000 in the WOS platform, despite having only 28 references. Notably, only four of the top 10 articles have been categorized as “Highly Cited Paper” in their respective categories, namely Bahram et al. (2018) (Biology & Biochemistry), Free et al. (2014) (Environment/Ecology), Brockett et al. (2012) (Agricultural Sciences), and Gavrilescu et al. (2015) (Biology & Biochemistry). Since 2013, Bahram et al. (2018) has been the most visited paper on the topic, based on the WOSCC database. The term “Highly Cited Paper” is defined by WOSCC as an article that has received sufficient citations to place it in the top 1% of the academic field based on a threshold between highly cited for the field and publication year. Furthermore, the study by Karl et al. (2002) had the highest number of references among the top 10 cited articles. Interestingly, most of the original papers in this field utilized less than 100 references as their primary sources of citation, except for the study by Karl et al. (2002). Other highly cited papers in this area focus on climate or climatic change, environmental stress, and greenhouse gas impact on microbe communities in marine environments (Beal et al., 2009; Ritchie, 2006; Inagaki et al., 2006; Niemann et al., 2006).
Web of Science 核心合集 (WOSCC) 生成的结果也出现在其引文报告中,其中列出了该领域被引用最多的 50 篇文章(补充材料 1 )。有关该主题的前 20 篇文章中近一半发表在《自然》或《科学》杂志上 (9/20)。全球被引用次数最多的 10 篇文章彼此相关(表 1 ),其中被引用次数最多的是Raghoebarsing 等人的研究。 (2006) ,尽管只有 28 篇参考文献,但在 WOSCC 数据库中获得了 891 次引用,在 WOS 平台中获得了 1000 次引用。值得注意的是,前 10 篇文章中只有 4 篇被归类为各自类别中的“高被引论文”,即Bahram 等人。 (2018) (生物学与生物化学), Free 等人。 (2014) (环境/生态), Brockett 等人。 (2012) (农业科学)和Gavrilescu 等人。 (2015) (生物学与生物化学)。自 2013 年以来, Bahram 等人。根据 WOSCC 数据库, (2018)是该主题访问量最大的论文。 WOSCC 将“高被引论文”一词定义为已获得足够引用,根据该领域高被引次数与出版年份之间的阈值将其置于学术领域前 1% 的文章。此外,卡尔等人的研究。 (2002)在被引用次数最多的 10 篇文章中引用次数最多。 有趣的是,除了Karl 等人的研究外,该领域的大多数原始论文都使用不到 100 篇参考文献作为主要引用来源。 (2002) 。该领域其他被高引用的论文主要关注气候或气候变化、环境压力以及温室气体对海洋环境中微生物群落的影响( Beal 等,2009Ritchie,2006Inagaki 等,2006Niemann 等,2006)。 ,2006 )。

Table 1. Top 10 highly cited articles based on the Web of Science Core Collection database, in the research on microbes associated with climate change within the marine environment (Accessed on 20 February 2023).
表 1 .基于 Web of Science 核心合集数据库的前 10 篇高被引文章,涉及海洋环境中与气候变化相关的微生物研究(2023 年 2 月 20 日访问)。

Reference 参考No. of citation in WOSCC/WOS platform
WOSCC/WOS平台引用次数
Journal (Highest Quartile/Impact Factor JCR, 2021)
期刊(最高四分位数/影响因子JCR,2021 年
Number of reference in the article
文章中参考文献数量
Climate change element(s), captured from TSa
气候变化要素,从 TS a捕获
Associated with the topic?b (Yes/No)
与主题相关吗? b (是/否)
Raghoebarsing et al., (2006)
Raghoebarsing 等人,(2006)
891/1000Nature (Q1/69.504) 自然 (Q1/69.504)28agricultural runoff 农业径流Yes 是的
Bahram et al., (2018) 巴赫拉姆等人,(2018)767/829Nature (Q1/69.504) 自然 (Q1/69.504)80environmental variables 环境变量No 
Free et al., (2014) 弗里等人,(2014)711/763Marine Pollution Bulletin (Q1/7.001)
海洋污染公报 (Q1/7.001)
95anthropogenic 人为的Yes 是的
Beal et al., (2009) 比尔等人,(2009)649/723Science (Q1/63.832) 科学(Q1/63.832)36climate 气候Yes 是的
Ritchie (2006) 里奇 (2006)619/629Marine Ecology Progress Series (Q2/2.915)
海洋生态进展系列(Q2/2.915)
52environmental stress 环境压力No 
Brockett et al., (2012) 布罗克特等人,(2012)616/703Soil Biology and Biochemistry (Q1/8.546)
土壤生物学和生物化学(Q1/8.546)
91climate 气候Yes 是的
Gavrilescu et al., (2015)
加夫里莱斯库等人,(2015)
613/628New Biotechnology (Q1/6.49)
新生物技术(Q1/6.49)
63anthropogenic 人为的Yes 是的
Karl et al., (2002) 卡尔等人,(2002)548/584Biogeochemistry (Q1/4.812)
生物地球化学(Q1/4.812)
207anthropogenic, climate, eutrophication
人为、气候、富营养化
Yes 是的
Inagaki et al., (2006) 稻垣等人,(2006)454/486PNASc (Q1/12.779)
PNAS c (Q1/12.779)
41climatic change 气候变化Yes 是的
Niemann et al. (2006) 尼曼等人。 (2006)440/487Nature (Q1/69.504) 自然 (Q1/69.504)30greenhouse gas 温室气体Yes 是的
a
TS (Topic Search: Searches title, abstract, author keywords, and Keywords Plus).
TS(主题搜索:搜索标题、摘要、作者关键字和关键字加)。
b
When all related keywords of marine, microbes and climate change elements are found or connected in the abstract.
当海洋、微生物和气候变化元素的所有相关关键词都在摘要中找到或连接起来时。
c
Proceedings of the National Academy of Sciences of the United States of America.
美利坚合众国国家科学院院刊。

3.3. Research cluster analysis
3.3.研究聚类分析

Through the scientometric analysis in relation to marine microbial studies within the climate change context, a network comprising 14 distinct clusters emerged (Fig. 3). Table 2 displays the top 10 ranked clusters along with their associated labels, determined by LSI, LLR, and MI algorithms. Fig. 4, presents the output of the timeline co-citation analysis and provides a visual representation of the key connections and trends in scientific research in the field of climate change and marine microbes over the past three decades.
通过与气候变化背景下的海洋微生物研究相关的科学计量分析,出现了一个由 14 个不同簇组成的网络(图 3 )。表 2显示了排名前 10 的簇及其相关标签,由 LSI、LLR 和 MI 算法确定。图4展示了时间线共被引分析的输出,并直观地展示了过去三十年气候变化和海洋微生物领域科学研究的关键联系和趋势。
Fig. 3
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Fig. 3. The reference co-citation research cluster network. Based on a one-year interval, a 14-cluster network of document co-citation with burst detection from 1986 to 2022. Node sizes are proportional to the frequency of the publications' co-citations.
图3 .参考同被引研究集群网络。基于一年的时间间隔,从 1986 年到 2022 年,具有突发检测的 14 个文档同被引集群网络。节点大小与出版物同被引的频率成正比。

Table 2. Top 10 ranked clusters and labels produced by LSI, LLR and MI on marine microbes-climate change-related studies.
表 2 . LSI、LLR 和 MI 在海洋微生物-气候变化相关研究中产生的排名前 10 的聚类和标签。

Cluster Size 尺寸Silhouette 轮廓Year Label (Latent Semantic Indexing)
标签(潜在语义索引)
Label (Log Likelihood Ratio)
标签(对数似然比)
Label (Mutual Information Algorithm)
标签(互信息算法)
01370.8872016ocean acidification 海洋酸化coral microbiome 珊瑚微生物组bacterial production 细菌生产
11270.882011marine bacteria 海洋细菌hypoxic zone 缺氧区freshwater phytoplankton 淡水浮游植物
2720.8962018bacterial communities 细菌群落novel Thermoplasmatota clade
新的热原体进化枝
salt-induced recruitment 盐诱导的募集
3700.9082015marine dinoflagellate bloom
海洋甲藻绽放
marine dinoflagellate bloom
海洋甲藻绽放
Beibu gulf China 中国北部湾
4620.9532016bacterial communities 细菌群落human health 人类健康microplastic-associated pathogen
微塑料相关病原体
5610.9582008high nutrient 高营养sponge-microbe association
海绵-微生物协会
cold-water coral Madrepora oculata
冷水珊瑚 M adrepora oculata
6500.9212011ocean acidification 海洋酸化ammonia-oxidizing bacteria
氨氧化细菌
plankton food-web 浮游生物食物网
7450.9972004automated phylogenetic tree-based small subunit rRNA taxonomy
基于自动系统发育树的小亚基 rRNA 分类
alignment pipeline 对齐管道coral atoll 珊瑚环礁
8380.9452008marine microplastics 海洋微塑料marine microplastics 海洋微塑料bacterial production 细菌生产
9380.9872009ocean acidification 海洋酸化mesopelagic zone ecology 中层带生态学Antarctic water 南极水
Fig. 4
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Fig. 4. Timeline co-citation cluster analysis. Nodes represent reference names, whereas lines represent connections between those references. Larger nodes indicate higher frequencies of citations. References with strong citation bursts are shown with red rings, whereas references having high centrality are shown with yellow nodes. The longer the colour line segment in the figure, the larger the time span of citations.
图4 .时间线共被引聚类分析。节点代表引用名称,而线代表这些引用之间的连接。节点越大表示引用频率越高。具有强引用爆发的参考文献用红色环显示,而具有高中心性的参考文献则用黄色节点显示。图中颜色线段越长,引用的时间跨度越大。

3.4. Author, institution and countries networks
3.4.作者、机构和国家网络

The investigation of climate change and its effects on marine microbes is a multidisciplinary and intricate domain that necessitates the involvement of diverse scientific disciplines, organizations, and authors. Therefore, exploring the top contributors in this area can provide valuable insights into the current research landscape and facilitate the identification of potential future research hotspots. Utilizing CiteSpace, the cooperation network clustering was generated and depicted in Fig. 5, while Table 3 presents a tabulated summary. These visualizations provide an extensive overview of the collaborative relationships among leading contributors in the research area.
气候变化及其对海洋微生物影响的研究是一个多学科且复杂的领域,需要不同科学学科、组织和作者的参与。因此,探索该领域的杰出贡献者可以为当前的研究格局提供有价值的见解,并有助于识别未来潜在的研究热点。利用 CiteSpace,生成了合作网络聚类并如图 5所示,而表 3提供了表格摘要。这些可视化提供了研究领域主要贡献者之间协作关系的广泛概述。
Fig. 5
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Fig. 5. Cooperation network among the countries and organizations in the study relating climate change and marine microbes between 1986 and 2022. Node size is proportional to the number of publications generated by a country or institution. Connections between nodes signify collaborative relationships between respective countries or institutions, with thicker connections denoting a higher degree of collaboration.
图5 。 1986年至2022年气候变化与海洋微生物研究中国家和组织之间的合作网络。节点规模与国家或机构发表的出版物数量成正比。节点之间的连线代表各个国家或机构之间的协作关系,连线越粗代表协作程度越高。

Table 3. Primary contributors of publications on the linkage between climate change and marine microbes from 1986 to 2022 based on authors, institutions, and countries.
表 3 . 1986 年至 2022 年关于气候变化与海洋微生物之间联系的出版物的主要贡献者(按作者、机构和国家划分)。

Authors 作者Record count 记录数Affiliations 隶属关系Record count 记录数Country 国家Record count 记录数
Zhang, Yue (Chinese Academy of Sciences, China)
张跃(中国科学院)
16Chinese Academy of Sciences, China
中国科学院
239USA856
Li Yi (Henan Normal University, China)
李毅(河南师范大学,中国)
14University of California system, USA
美国加州大学系统
155China 中国524
Webster, Nicole S. (University of Queensland, Australia)
Webster, Nicole S.(澳大利亚昆士兰大学)
14Centre national de la recherche Scientifique (CNRS), France
法国国家科学研究中心 (CNRS)
125Germany 德国301
Wang, Yibo (Chinese Academy of Sciences, China)
王一波(中国科学院)
13The Helmholtz Association of German Research Centres
德国亥姆霍兹研究中心协会
121Australia 澳大利亚234
Zhou, Jin (Tsinghua University, China)
周金(中国清华大学)
13UDICE French Research Universities, France
法国 UDICE 法国研究型大学
104England 英格兰185
Hutchins, David A (University of Southern California, USA)
大卫·A·哈钦斯(美国南加州大学)
12Spanish National Research Council, Spain
西班牙国家研究委员会,西班牙
68France 法国179
Seymour, Justin R. (University of Technology Sydney, Australia)
Seymour, Justin R.(澳大利亚悉尼科技大学)
12Sorbonne Universite, France
法国索邦大学
63Canada 加拿大158
Chen, Ji (Aarhus University, China)
陈吉(奥胡斯大学,中国)
11State University System of Florida, USA
美国佛罗里达州立大学系统
54Spain 西班牙149
Chen, Yin (University of Warwick Ocean University of China)
陈寅(英国华威大学、中国海洋大学)
11Institut de Recherche pour le Développement, France
法国发展研究所
52Italy 意大利129
Jiao, Nianzhi (Xiamen University, China)
焦念智(厦门大学,中国)
11Russian Academy of Sciences
俄罗斯科学院
52India 印度122

3.5. Keywords Co-occurrences analysis
3.5.关键词共现分析

The keyword co-occurrence analysis yielded valuable insights into current research trends. Using CiteSpace, 819 keywords and 3742 links were identified from 1986 to 2022. The analysis unveiled 14 keyword clusters (Fig. 6), signifying research hotspots and frontiers in this domain. Each cluster can be further characterized by unique descriptors, as presented in Table 4. This approach proves effective in pinpointing research trends and emerging areas in the study of climate change's impact on marine microbes. Fig. 7, depicts a historical overview of the emerging research topics in marine microbial studies with respect to climate change. Keyword timeline analysis was employed to identify the development of research themes in the field over the past thirty years. The listed keywords were ordered chronologically and based on their frequency of usage.
关键词共现分析为当前研究趋势提供了宝贵的见解。使用CiteSpace,从1986年到2022年识别出819个关键词和3742个链接。分析揭示了14个关键词簇(图6 ),标志着该领域的研究热点和前沿。每个簇都可以通过独特的描述符进一步表征,如表 4所示。事实证明,这种方法可以有效地确定气候变化对海洋微生物影响研究的研究趋势和新兴领域。图7描绘了与气候变化有关的海洋微生物研究中新兴研究主题的历史概述。采用关键词时间线分析来确定过去三十年来该领域研究主题的发展。列出的关键字按时间顺序并根据其使用频率排序。
Fig. 6
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Fig. 6. Distribution of co-cited clustered keywords in the impact of climate change on marine microbes related research between 1986 and 2022.
图6 . 1986年至2022年气候变化对海洋微生物影响相关研究中同被聚类关键词的分布。

Table 4. Most frequent keyword label describing the cluster label for marine microbe and climate change literature (1986–2022).
表 4 .描述海洋微生物和气候变化文献聚类标签的最常见关键词标签(1986-2022)。

Cluster Cluster label 簇标签Keyword descriptors 关键词描述符
#0Microbial diversity 微生物多样性microbial community, dynamics, bacterial community, sea, ocean, patterns, bacterial, abundance, identification, variability, biodiversity, microbial diversity, bacterioplankton, evolution, biogeography, coastal, assemblages, dissolved organic matter, 16s ribosomal RNA, archaea, harmful algal blooms, iron, microbes, microbial ecology, genes
微生物群落、动力学、细菌群落、海、海洋、模式、细菌、丰度、识别、变异性、生物多样性、微生物多样性、浮游细菌、进化、生物地理学、沿海、组合、溶解有机物、16s核糖体RNA、古细菌、有害藻华, 铁, 微生物, 微生物生态学, 基因
#1Ocean acidification 海洋酸化ocean acidification, Escherichia coli, eutrophication, water quality, pollution, coral reefs, impacts, gene expression, marine environment, baltic sea, contamination, surface, disease, microbial communities, ph, particles, bay, biosynthesis, distributions, river, management, survival, biofilms, health, Atlantic ocean, metagenomic analysis, seasonal variation
海洋酸化、大肠杆菌、富营养化、水质、污染、珊瑚礁、影响、基因表达、海洋环境、波罗的海、污染、表面、疾病、微生物群落、酸碱度、颗粒、海湾、生物合成、分布、河流、管理、生存、生物膜、健康、大西洋、宏基因组分析、季节变化
#2Bacteria characteristics 细菌特性Bacteria, community structure, populations, antibiotic resistance, environment, fatty acids, flow cytometry, environments, virus, insights, soils, ammonia oxidation, assimilation, lipid biomarkers, antibiotic resistance genes, record, environmental impact, recovery, systems, consumption, aquatic environments, particulate matter, genetic diversity, bacillus cereus, oxygen depletion
细菌、群落结构、种群、抗生素耐药性、环境、脂肪酸、流式细胞术、环境、病毒、见解、土壤、氨氧化、同化、脂质生物标志物、抗生素耐药性基因、记录、环境影响、恢复、系统、消费、水生环境、颗粒物、遗传多样性、蜡样芽孢杆菌、缺氧
#3Carbon Carbon, growth, nitrogen, degradation, oxidation, reduction, waste water, crude oil, acid, bioremediation, performance, polycyclic aromatic hydrocarbons, toxicity, constructed wetlands, removal, microalgae, risk assessment, hydrogen peroxide, degrading bacteria, antioxidant enzymes, copper, north Atlantic, Saccharomyces cerevisiae, growth rate, plant growth promotion, emissions
碳、生长、氮、降解、氧化、还原、废水、原油、酸、生物修复、性能、多环芳烃、毒性、人工湿地、去除、微藻、风险评估、过氧化氢、降解细菌、抗氧化酶、铜, 北大西洋,酿酒酵母, 生长速度, 植物生长促进, 排放
#4Organic matter 有机物Phytoplankton, organic matter, climate, phosphorus, metabolism, nitrogen fixation, expression, transport, CO2, rates, photosynthesis, north sea, origin, life, N2 fixation, surface sediments, dimethyl sulphide, extracellular polymeric substances, deposition, basin, amino acids, chemical composition, nutrients, chemistry, population dynamics, biogeochemical processes
浮游植物、有机质、气候、磷、代谢、固氮、表达、运输、CO 2 、速率、光合作用、北海、起源、生命、N 2固定、表面沉积物、二甲基硫醚、细胞外聚合物、沉积、盆地、氨基酸、化学成分、营养素、化学、种群动态、生物地球化学过程
#5Salinity stress 盐度胁迫Diversity, climate change, soil, salinity, responses, impact, drought, plant growth, stress, tolerance, arbuscular Mycorrhizal fungi, salt stress, plants, rhizosphere, oxidative stress, colonization, drought stress, microbial community structure, abiotic stress
多样性、气候变化、土壤、盐度、反应、影响、干旱、植物生长、胁迫、耐受性、丛枝菌根真菌、盐胁迫、植物、根际、氧化胁迫、定殖、干旱胁迫、微生物群落结构、非生物胁迫
#6Nitrification 硝化作用fresh water, denitrification, nitrification, sulfate-reducing bacteria, community composition, ecosystems, nitrate, water column, anaerobic oxidation, sulfate reduction, oxygen, salt marsh, nitrous oxide, ammonia-oxidizing archaea, hypoxia, Atlantic, ammonia-oxidizing bacteria, productivity, Spartina alterniflora, dissolved organic carbon
淡水、反硝化、硝化、硫酸盐还原菌、群落组成、生态系统、硝酸盐、水柱、厌氧氧化、硫酸盐还原、氧气、盐沼、一氧化二氮、氨氧化古菌、缺氧、大西洋、氨氧化细菌、生产力,互花米草, 溶解有机碳
#7Marine 海洋Marine, biomass, organic carbon, mechanisms, blooms, cyanobacteria, microbial biomass, biogeochemistry, respiration, light, decomposition, enzyme activity, microbial mats, elevated CO2, wetland, limitation, intertidal sediments, dioxide, El Niño, precipitation
海洋、生物量、有机碳、机制、水华、蓝藻、微生物生物量、生物地球化学、呼吸、光、分解、酶活性、微生物垫、CO 2升高、湿地、限制、潮间沉积物、二氧化硫、厄尔尼诺现象、降水
#8Gen. Nov 十一月将军Sediments, water, sp. nov, gen. nov, biodegradation, bacterial diversity, marine bacteria, system, algae, fungi, gulf of Mexico, great barrier reef, reef, waste, mineralization, geochemistry, humic substances, anaerobic oxidation of methane, cultivation, high-throughput sequencing, sequence, calcium carbonate precipitation, soil microbial community
沉积物、水、sp。十一月将军nov, 生物降解, 细菌多样性, 海洋细菌, 系统, 藻类, 真菌, 墨西哥湾, 大堡礁, 珊瑚礁, 废物, 矿化, 地球化学, 腐殖质, 甲烷厌氧氧化, 培养, 高通量测序, 序列, 钙碳酸盐降水、土壤微生物群落
#916srRNAMicroorganisms, accumulation, 16S rRNA, sequences, resistance, calcification, resilience, microbiome, ingestion, biofilm formation, methane production, indicators, antimicrobial resistance, phylogeny, aerosol, equatorial pacific, ice, cadmium, fungal community, calcite, cloud water, growth promotion, phylogenetic analysis
微生物、积累、16S rRNA、序列、耐药性、钙化、复原力、微生物组、摄入、生物膜形成、甲烷产生、指标、抗菌药物耐药性、系统发育、气溶胶、赤道太平洋、冰、镉、真菌群落、方解石、云水、生长推广、系统发育分析
Fig. 7
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Fig. 7. Keyword timeline co-occurrence network from 1986 to 2022 for marine microbe and climate change-related publications.
图7 . 1986年至2022年海洋微生物和气候变化相关出版物的关键词时间线共现网络。

4. Discussion 4. 讨论

4.1. Quantitative analysis
4.1.定量分析

Although an exponential trend is observed in this research area, it may not necessarily translate to a noticeable increase in research activity. A total of 677 different journals have published articles on the topic. Notably, the two top journals in this field are highly ranked and have a significant impact factor (IF) (JCR, 2021): Science of the Total Environment (IF: 10.754, Quartile 1, ranking 26/279) and Frontiers in Microbiology (IF: 6.064, Quartile 1, ranking 34/137). The advent of open-access publishing has been a critical debate in the field for the last few decades (Laakso et al., 2011), which could also influence research activity and visibility. Open-access options not only offer unique opportunities for emerging subject areas to establish dedicated journals, but they also tend to receive higher citations, as they are freely available on the internet without any subscription requirements. The present study revealed that the research areas had hovered around 42.1% (107/254) of the total WOS categories provided by Clarivate Analytics (Web of Knowledge, 2023), indicating that the research area attracts almost half of the WOS categories, despite being focused on the marine environment. Identifying the most cited articles in the field could help researchers identify high-quality research (Levitt and Thelwall, 2009; Sahoo et al., 2020). The present study also found that articles published in Nature or Science journals received higher citations compared to other articles (Niemann et al., 2006; Raghoebarsing et al., 2006; Beal et al., 2009; Bahram et al., 2018), suggesting that higher impact factors of the journal could attract various authors for future references and citations. Notably, Nature and Science journals cover a wide range of scientific fields (multidisciplinary fields), including biology, physics, chemistry, earth sciences, etc.
尽管在该研究领域观察到指数趋势,但它不一定会转化为研究活动的显着增加。共有 677 种不同的期刊发表了有关该主题的文章。值得注意的是,该领域的两本顶级期刊排名很高,并且具有显着的影响因子( JCR,2021 ):Science of the Total Environment(IF:10.754,Quartile 1,排名 26/279)和 Frontiers in Microbiology (JCR,2021): IF:6.064,四分位数 1,排名 34/137)。过去几十年来,开放获取出版的出现一直是该领域的一个关键争论( Laakso 等人,2011 ),这也可能影响研究活动和知名度。开放获取选项不仅为新兴学科领域建立专门期刊提供了独特的机会,而且它们也往往会获得更高的引用,因为它们可以在互联网上免费获取,无需任何订阅要求。本研究显示,该研究领域徘徊在 Clarivate Analytics( Web of Knowledge,2023 )提供的 WOS 类别总数的 42.1%(107/254)左右,这表明该研究领域吸引了近一半的 WOS 类别,尽管重点关注海洋环境。识别该领域被引用最多的文章可以帮助研究人员识别高质量的研究( Levitt 和 Thelwall,2009Sahoo 等人,2020 )。 本研究还发现,与其他文章相比,在《自然》或《科学》杂志上发表的文章获得了更高的引用( Niemann 等人,2006 年Raghoebarsing 等人,2006 年Beal 等人,2009 年Bahram 等人,2018 年),这表明该期刊较高的影响因子可以吸引不同的作者未来的参考和引用。值得注意的是,Nature和Science期刊涵盖了广泛的科学领域(多学科领域),包括生物学、物理学、化学、地球科学等。
In a refined analysis of keywords, we suggest focusing exclusively on “microbes” and “microorganisms,” eliminating “single cell"-related terms. Previous analyses incorporated keywords like “microscopic size organism” and “single cell”; however, the majority of those studies pertained to cell-related chemistry rather than the current topic. The WOSCC database generated climate change-related keywords, but we recommend excluding terms such as “environmental variables,” as used by Bahram et al. (2018), for future scientometric-based articles, especially when considering climate change-related synonyms. Alternatively, we propose incorporating keywords like “environmental stress” in future scientometric-based analyses, given their relevance to climate change factors. Notably, although review articles were excluded from our search process, Karl et al.'s (2002) study was included in the WOSCC data, likely due to its categorization as an “Article” within the database.
在对关键词进行精细分析时,我们建议只关注“微生物”和“微生物”,消除“单细胞”相关术语。之前的分析纳入了“微观生物体”和“单细胞”等关键词;然而,大多数这些研究涉及细胞相关化学,而不是当前主题,WOSCC 数据库生成了与气候变化相关的关键词,但我们建议排除Bahram 等人(2018)所使用的术语,以供未来的科学计量使用。或者,我们建议在未来基于科学计量的分析中纳入“环境压力”等关键词,因为它们与气候变化因素的相关性值得注意,尽管评论文章被排除在我们的搜索过程之外。 Karl 等人 (2002) 的研究被纳入 WOSCC 数据中,可能是因为它在数据库中被归类为“文章”。

4.2. Scientometric discussion
4.2.科学计量学讨论

4.2.1. Focused research area (cluster analysis)
4.2.1.重点研究领域(聚类分析)

The largest cluster (#0) exhibited a silhouette value of 0.887 and consisted of 137 members. Identified as the coral microbiome cluster by LLR, the ocean acidification cluster by LSI, and the bacterial production cluster by MI, this cluster highlights the interrelationship between climate change and coral reefs. The presence of this cluster reflects the underlying connection, as coral reefs are known to be highly sensitive to alterations in water temperature and acidity. The vast metabolic capabilities and adaptive evolution mechanisms of coral-associated bacterial communities could contribute to their hosts' ability to adapt to changing environmental conditions (McFall-Ngai et al., 2013a, McFall-Ngai et al., 2013b; Torda et al., 2017a, Torda et al., 2017b). The bacteria found within the coral host's microhabitats have been suggested to play roles in immunity, nutrient cycling, nitrogen fixation, osmoregulation, and oxidative stress responses (Bourne et al., 2016; Torda et al., 2017a, Torda et al., 2017b). Recent research has revealed significant differences between resident and active microbial communities in long-term aquarium-maintained Stylophora pistillata, with stronger effects of ocean acidification observed on the active community (Barreto et al., 2021). Notable findings from this cluster include the identification of various bacterial taxa that may play essential roles in coral health and the potential for these microbes to mitigate the effects of ocean acidification (Sogin et al., 2006; Jousset et al., 2017a, Jousset et al., 2017b; Barreto et al., 2021).
最大的簇 (#0) 的轮廓值为 0.887,由 137 个成员组成。该簇被 LLR 识别为珊瑚微生物群、被 LSI 识别为海洋酸化簇、被 MI 识别为细菌产生簇,强调了气候变化与珊瑚礁之间的相互关系。该簇的存在反映了潜在的联系,因为众所周知,珊瑚礁对水温和酸度的变化高度敏感。珊瑚相关细菌群落的巨大代谢能力和适应性进化机制可能有助于其宿主适应不断变化的环境条件的能力( McFall-Ngai 等,2013aMcFall-Ngai 等,2013bTorda 等,2013)。 ,2017aTorda 等人,2017b )。在珊瑚宿主的微生境中发现的细菌被认为在免疫、营养循环、固氮渗透调节氧化应激反应中发挥作用( Bourne 等人,2016Torda 等人,2017aTorda 等人,2017b) )。 最近的研究揭示了长期在水族箱中维持的Stylophora pistillata 的常驻微生物群落和活跃微生物群落之间存在显着差异,并且观察到海洋酸化对活跃群落的影响更强( Barreto 等人,2021 )。该集群的显着发现包括识别出可能在珊瑚健康中发挥重要作用的各种细菌类群,以及这些微生物减轻海洋酸化影响的潜力( Sogin 等人,2006 年Jousset 等人,2017aJousset 等人)等人,2017b巴雷托等人,2021 )。
The cluster designated as the hypoxic zone cluster by LLR, the marine bacteria cluster by LSI, and the freshwater phytoplankton cluster by MI was the second-largest (#1), comprising 127 members with a silhouette value of 0.88. This cluster was closely associated with the impact of climate change on the availability of oxygen in the water, which can significantly affect microbial communities. The findings of this cluster highlighted several bacterial taxa that have adapted to low-oxygen environments and their potential role in nutrient cycling in the ocean. The lack of oxygen, or hypoxia, in water is typically caused by the increased microbial respiration that accompanies organic material decomposition. In cases where the process of reoxygenation is limited by factors such as water-column stratification or the residence time of a body of water, oxygen concentrations become insufficient for normal biological functions, leading to the formation of dead zones (Altieri and Diaz, 2019). Dead zones, caused by the depletion of dissolved oxygen in coastal waters, represent one of the most widespread and damaging anthropogenic threats to marine ecosystems worldwide. Such zones have doubled in frequency every decade since the mid-1900s (Rabalais et al., 2010a, Rabalais et al., 2010b; Altieri and Gedan, 2015). The impact of ocean acidification (OA) is closely linked to dead zones in coastal waters, as the generation of hypoxic conditions and high levels of CO2 during the respiration of microbes and algal blooms also lower the pH. Thus, hypoxic dead zones may serve as potential hotspots for acidification, as they typically exhibit lower pH values (Duarte et al., 2013; Altieri and Gedan, 2015).
LLR 指定为缺氧区簇、LSI 指定为海洋细菌簇、MI 指定为淡水浮游植物簇是第二大簇(#1),包含 127 个成员,轮廓值为 0.88。该集群与气候变化对水中氧气可用性的影响密切相关,这可以显着影响微生物群落。该簇的发现强调了几种适应低氧环境的细菌类群及其在海洋养分循环中的潜在作用。水中缺氧或缺氧通常是由于有机物质分解引起的微生物呼吸增加引起的。如果再充氧过程受到水柱分层或水体停留时间等因素的限制,氧气浓度将不足以维持正常的生物功能,从而导致死区的形成( Altieri 和 Diaz,2019 ) 。由沿海水域溶解氧耗尽引起的死亡区是全球海洋生态系统最广泛、最具破坏性的人为威胁之一。自 1900 年代中期以来,此类区域的频率每十年翻一番( Rabalais 等人,2010aRabalais 等人,2010bAltieri 和 Gedan,2015 )。 海洋酸化 (OA) 的影响与沿海水域的死区密切相关,因为微生物和藻华呼吸过程中缺氧条件和高浓度 CO 2的产生也会降低 pH 值。因此,缺氧死区可能成为潜在的酸化热点,因为它们通常表现出较低的 pH 值( Duarte 等人,2013 年Altieri 和 Gedan,2015 年)。
The third-largest cluster (#2), which consisted of 72 members and displayed a silhouette value of 0.896, was characterized by LLR as the novel Thermoplasmatota clade cluster, by LSI as the bacterial communities cluster, and by MI as the salt-induced recruitment cluster. This cluster was associated with the impact of climate change on microbial communities thriving in extreme environments such as hot springs and salt lakes. The Thermoplasmatota clade is an archaeal phylum that is distributed worldwide and is ecologically significant, comprising multiple classes such as Aciduliprofundales, Thermoplasmatales, Methanomassiliicoccales, and “Candidatus Poseidoniales” (Zheng et al., 2022). This cluster revealed several novel bacterial taxa that have adapted to high-temperature and high-salinity environments and may be used in various biotechnology applications. This group is prevalent in ocean surface waters and has been found to contain proteorhodopsin, a protein that allows for photoheterotrophy, indicating its ability to utilize light energy to break down organic compounds (Rinke et al., 2019; Da Silva et al., 2022). Relevant studies in this field include those conducted by Zheng et al. (2022), Rinke et al. (2019), and Da Silva et al. (2022). Major citing articles under this cluster is by Hutchins and Fu (2017) and Royo-Llonch et al. (2021).
第三大簇 (#2) 由 72 个成员组成,轮廓值为 0.896,其特征为 LLR 为新的热原体进化枝簇,LSI 为细菌群落簇,MI 为盐诱导的细菌群落簇。招聘集群。该集群与气候变化对温泉和盐湖等极端环境中繁衍生息的微生物群落的影响有关。热原体菌是一个分布于世界各地、具有重要生态意义的古菌门,包括Aceduliprofundales、 Thermoplasmatales 、Methanomassiliicoccales和“ Candidatus Poseidoniales ”等多个纲( Zheng et al., 2022 )。该簇揭示了几种适应高温和高盐度环境的新型细菌类群,可用于各种生物技术应用。该组在海洋表面水域中普遍存在,并被发现含有原视紫红质,这是一种允许光异养的蛋白质,表明其能够利用光能分解有机化合物( Rinke 等人,2019 年Da Silva 等人,2022 年) )。该领域的相关研究包括郑等人的研究。 (2022)林克等人。 (2019)达席尔瓦等人。 (2022) 。 该簇下的主要施引文章来自Hutchins 和 Fu (2017)以及Royo-Llonch 等人。 (2021)
The cluster with the fourth-largest number of members (#3) had a silhouette value of 0.908 and was classified as the marine dinoflagellate bloom cluster by LLR and LSI, and the Beibu Gulf China cluster by MI. This cluster was associated with the impact of climate change on harmful algal blooms, which can cause significant effects on both the ecosystem and human health. Some of the key findings from this cluster included the discovery of various bacterial taxa that could play a role in regulating harmful algal blooms and the potential use of these microbes as biocontrol agents. The bacterial community structure can be highly complex during phytoplankton blooms and can change throughout the bloom cycle depending on factors such as the algal species, physiological state, environmental conditions, and bloom stage (Zhou et al., 2018). There have been several studies that have examined the changes in bacterial community structure during natural and semi-natural phytoplankton blooms (Theroux et al., 2012; Zhou et al., 2018). These scientific findings reveal the importance of understanding the dynamics of bacterial communities during phytoplankton blooms, along with the potential for these communities to regulate harmful algal blooms and promote marine ecosystem health.
成员数第四多的簇(#3)的轮廓值为0.908,被LLR和LSI分类为海洋甲藻水华簇,被MI分类为中国北部湾簇。该集群与气候变化对有害藻华的影响有关,有害藻华可能对生态系统和人类健康造成重大影响。该集群的一些关键发现包括发现了各种细菌类群,这些细菌类群可以在调节有害藻华方面发挥作用,以及这些微生物作为生物防治剂的潜在用途。浮游植物水华期间,细菌群落结构可能非常复杂,并且会在整个水华周期中发生变化,具体取决于藻类种类、生理状态、环境条件和水华阶段等因素( Zhou et al., 2018 )。有几项研究考察了自然和半自然浮游植物繁殖过程中细菌群落结构的变化( Theroux等,2012Zhou等,2018 )。这些科学发现揭示了了解浮游植物繁殖期间细菌群落动态的重要性以及这些群落调节有害藻类繁殖和促进海洋生态系统健康的潜力。
The fifth-largest cluster (#4) consisted of 62 members. It was referred to as the human health cluster by LLR, the bacterial communities cluster by LSI, and the microplastic-associated pathogen cluster by MI. This cluster was linked to research on the potential health impacts of bacterial communities associated with environmental microplastics. The studies within this cluster aimed to explore the presence, abundance, and distribution of microplastics in the environment, the bacterial communities associated with microplastics, and the potential risk of microplastic-associated pathogens to human health. The high silhouette value of 0.953 suggests that the members of this cluster share high similarity with each other and can be considered a distinct research area on its own. Concerns have been raised regarding the potential hazards of microplastic-associated microbial communities. Studies have identified members of the Vibrio genus as being enriched on microplastics; however, some have contested this finding (Zettler et al., 2013; Bryant et al., 2016; Oberbeckmann et al., 2018). Biogeographical and environmental factors, such as salinity and nutrient concentration, are major determinants of marine microplastic biofilm composition (Amaral-Zettler et al., 2015; Oberbeckmann et al., 2018). Additionally, microplastics have been reported to act as carriers for antibiotic-resistance genes and facilitate pathogenic microorganisms' colonization (Oberbeckmann et al., 2018).
第五大集群 (#4) 由 62 名成员组成。 LLR 将其称为人类健康簇,LSI 将其称为细菌群落簇,MI 将其称为微塑料相关病原体簇。该集群与环境微塑料相关细菌群落潜在健康影响的研究有关。该集群中的研究旨在探索环境中微塑料的存在、丰度和分布、与微塑料相关的细菌群落,以及与微塑料相关的病原体对人类健康的潜在风险。 0.953 的高轮廓值表明该簇的成员彼此具有很高的相似性,并且可以被认为是一个独特的研究领域。人们对与微塑料相关的微生物群落的潜在危害表示担忧。研究已发现弧菌属成员富含微塑料;然而,一些人对这一发现提出质疑( Zettler 等人,2013 年Bryant 等人,2016 年Oberbeckmann 等人,2018 年)。生物地理和环境因素,例如盐度和营养物浓度,是海洋微塑料生物膜组成的主要决定因素( Amaral-Zettler 等,2015Oberbeckmann 等,2018 )。 此外,据报道,微塑料可以作为抗生素抗性基因的载体,促​​进病原微生物的定植( Oberbeckmann 等,2018 )。
The sixth largest cluster (#5) is comprised of 61 members with a silhouette value of 0.958. It was classified as the sponge-microbe association cluster by LLR, high nutrient cluster by LSI, and cold-water coral Madrepora oculata cluster by MI. The research on this cluster links to the climate change impact on microbial communities in deep-sea environments that are extremely sensitive to changes in temperature and nutrient levels. The crucial findings from this cluster reveal the identification of distinct bacterial taxa linked to deep-sea corals and sponges' well-being, which offer potential for microbial applications in biotechnology. Research has suggested that various sponges across different oceans contain ubiquitous bacteria, with some bacterial clades found in sponges more similar to each other than to other environments (Taylor et al., 2007; Webster et al., 2008). Studies have identified distinct microbial communities in sponges not found in the surrounding seawater, and some bacteria have been found in numerous sponge species, such as the bacterial candidate phylum ‘Poribacteria,’ with <75% 16S rRNA sequence homology to any previously identified bacteria (Fieseler et al., 2004).
第六大簇 (#5) 由 61 个成员组成,轮廓值为 0.958。 LLR将其分类为海绵-微生物关联簇,LSI将其分类为高营养簇,MI将其分类为冷水珊瑚Madrepora oculata簇。对该簇的研究与气候变化对深海环境中微生物群落的影响有关,这些环境对温度和营养水平的变化极其敏感。该集群的重要发现揭示了与深海珊瑚和海绵的健康相关的独特细菌类群的识别,这为微生物在生物技术中的应用提供了潜力。研究表明,不同海洋的各种海绵都含有普遍存在的细菌,海绵中发现的一些细菌进化枝彼此之间比其他环境更相似( Taylor 等人,2007 年Webster 等人,2008 年)。研究已经在海绵中发现了周围海水中未发现的独特微生物群落,并且在许多海绵物种中发现了一些细菌,例如细菌候选门“Poribacteria”,与任何先前识别的细菌具有%3C75%16S rRNA序列同源性菲瑟勒等人,2004 )。
The seventh-largest cluster (#6) had a silhouette value of 0.921 and comprised 50 members. It was identified as the ammonia-oxidizing bacteria cluster by LLR, the ocean acidification cluster by LSI, and the plankton food-web cluster by MI. This cluster was linked to the impact of climate change on microbial communities in the ocean, which play a crucial role in nutrient cycling and the health of the food web. Key findings from this cluster include identifying several bacterial taxa involved in nitrogen cycling in the ocean and their potential role in mitigating the effects of ocean acidification. For example, AOA or thaumarchaea, which can make up almost 40% of marine microbial plankton, have been found to be the primary drivers of nitrification in the marine environment (Prosser & Nicol, 2008; Qin et al., 2014). Planktonic thaumarchaea are chemolithotrophic ammonia oxidizers, which means they oxidize ammonia for energy and fix inorganic carbon into biomass (Santoro et al., 2019). Their activities have significant implications for trophic interactions, including primary production and carbon export to the deep ocean, and their high copper requirements may impact food web dynamics. Furthermore, AOA has been identified as a source of greenhouse gases, such as nitrous oxide and, indirectly, methane (Amin et al., 2013; Qin et al., 2014). Thaumarchaea is able to access reduced nitrogen from urea to support their energy-generating metabolism, and cyanate utilization has been demonstrated in non-marine thaumarchaea (Palatinszky et al., 2015; Tolar et al., 2017; Santoro et al., 2019).
第七大簇 (#6) 的轮廓值为 0.921,由 50 个成员组成。 LLR 鉴定为氨氧化菌簇,LSI 鉴定为海洋酸化菌簇,MI 鉴定为浮游生物食物网簇。该集群与气候变化对海洋微生物群落的影响有关,海洋微生物群落在营养循环和食物网的健康中发挥着至关重要的作用。该集群的主要发现包括确定了几种参与海洋氮循环的细菌类群及其在减轻海洋酸化影响方面的潜在作用。例如,AOA或taumarchaea几乎占海洋浮游微生物的40%,已被发现是海洋环境中硝化作用的主要驱动因素( Prosser & Nicol,2008Qin等,2014 )。浮游taumarchaea是化学营养型氨氧化剂,这意味着它们氧化氨以获取能量并将无机碳固定为生物质( Santoro等人,2019 )。它们的活动对营养相互作用具有重大影响,包括初级生产和向深海的碳输出,它们的高铜需求可能会影响食物网动态。此外,AOA 已被确定为温室气体的来源,例如一氧化二氮和间接的甲烷( Amin 等人,2013 年Qin 等人,2014 年)。 奇马菌能够从尿素中获取减少的氮来支持其能量生成代谢,并且氰酸盐的利用已在非海洋奇马菌中得到证实( Palatinszky 等,2015Tolar 等,2017Santoro 等,2019 ) 。
The eighth-largest cluster (#7) had a silhouette value of 0.997 and consisted of 45 members. It was identified as the alignment pipeline cluster by LLR, the automated phylogenetic tree-based small subunit rRNA taxonomy cluster by LSI, and the coral atoll cluster by MI. This cluster was linked to the development and application of bioinformatics tools for the analysis of microbial communities. Key findings from this cluster include the identification of various tools for analyzing microbial diversity, including metagenomics, phylogenetics, and functional gene analysis. These tools are powerful in characterizing microbial communities and their potential roles in various ecosystems, such as nutrient cycling, energy production, and bioremediation. Moreover, the integration of various bioinformatics tools and techniques provides a comprehensive understanding of microbial communities and their complex interactions with the environment. Further, the development and application of bioinformatics tools have significant implications for discovering novel microbial functions, identifying new microbial species, and developing innovative biotechnologies. The potential applications of these tools are broad, including bioprospecting, bioremediation, and drug discovery, among others (Glöckner and Joint, 2010; Ambrosino et al., 2019; Rudovica et al., 2021).
第八大簇 (#7) 的轮廓值为 0.997,由 45 个成员组成。它被 LLR 确定为比对管道簇,被 LSI 确定为基于自动系统发育树的小亚基 rRNA 分类簇,被 MI 确定为珊瑚环礁簇。该集群与用于分析微生物群落的生物信息学工具的开发和应用相关。该集群的主要发现包括确定了用于分析微生物多样性的各种工具,包括宏基因组学、系统发育学和功能基因分析。这些工具在描述微生物群落及其在各种生态系统中的潜在作用(例如养分循环、能源生产和生物修复)方面非常有用。此外,各种生物信息学工具和技术的集成提供了对微生物群落及其与环境的复杂相互作用的全面了解。此外,生物信息学工具的开发和应用对于发现新的微生物功能、识别新的微生物物种和开发创新生物技术具有重要意义。这些工具的潜在应用非常广泛,包括生物勘探、生物修复和药物发现等( Glöckner 和 Joint,2010Ambrosino 等,2019Rudovica 等,2021 )。
The ninth-largest cluster (#8) had a silhouette value of 0.984 and consisted of 41 members. It was identified as the microbial fuel cell cluster by LLR, the bioelectricity cluster by LSI, and the sediment microbial community cluster by MI. This cluster was linked to developing and applying microbial fuel cells for wastewater treatment and bioelectricity production. Microbial fuel cells (MFCs) are an attractive, sustainable energy source that utilizes sediment microorganisms to convert solar energy into bioelectricity (Rusyn, 2021). The process involves microorganisms oxidizing substrates to release electrons, which an oxidizing agent then accepts to establish a REDOX pair within the bioelectrochemical reactor (Lu et al., 2021; Feregrino-Rivas et al., 2023). Sediments from rivers, seas, and lagoons are commonly used as the substrate for MFCs, where electrochemically active microorganisms oxidize sediment sulfide and organic carbon at the anode, generating an external electrical current that can be harvested (Feregrino-Rivas et al., 2023). Moreover, MFC installation coupled with in-situ AC amendment in sediment can simultaneously produce renewable energy and bioremediation of heavy metals and hydrophobic organic compounds (Sudirjo et al., 2019). Overall, MFCs are a promising technology for sustainable energy production and environmental remediation that rely on the metabolic processes of sediment microorganisms.
第九大簇 (#8) 的轮廓值为 0.984,由 41 个成员组成。 LLR 鉴定为微生物燃料电池簇,LSI 鉴定为生物电簇,MI 鉴定为沉积物微生物群落簇。该集群与开发和应用微生物燃料电池进行废水处理和生物电生产有关。微生物燃料电池(MFC)是一种有吸引力的可持续能源,它利用沉积物微生物将太阳能转化为生物电( Rusyn,2021 )。该过程涉及微生物氧化底物以释放电子,然后氧化剂接受电子,在生物电化学反应器内建立氧化还原对( Lu 等人,2021Feregrino-Rivas 等人,2023 )。来自河流、海洋和泻湖的沉积物通常用作 MFC 的底物,其中电化学活性微生物在阳极氧化沉积物硫化物和有机碳,产生可收集的外部电流 Feregrino-Rivas 等人,2023 ) 。此外,MFC安装与沉积物中的原位AC修正相结合,可以同时产生可再生能源和重金属和疏水性有机化合物的生物修复( Sudirjo等人,2019 )。总体而言,MFC 是一种有前景的可持续能源生产和环境修复技术,依赖于沉积物微生物的代谢过程。
The tenth-largest cluster (#9) had a silhouette value of 0.994 and consisted of 38 members. It was identified as the iron-oxidizing bacteria cluster by LLR, the heavy metal cluster by LSI, and the acid mine drainage cluster by MI. This cluster was linked to the impact of mining activities on the microbial communities in acid mine drainage environments. The identification of bacterial taxa involved in iron oxidation is a significant finding of this cluster, with potential applications in bioremediation technologies for heavy metal pollution treatment. Acid mine drainage (AMD) is produced by the chemical and microbial oxidation of sulfide mineral waste rock, which is a byproduct of mining activities (Leduc et al., 2002). These microbes have developed a unique ability to thrive in extremely acidic environments, and their contribution to the sulfur and iron biogeochemical cycle is immense (Fashola et al., 2015). However, AMD poses a severe environmental problem due to the extreme acidity, high concentration of heavy metals, salinity, and ferric iron precipitation, leading to the destruction of the surrounding biota (Leduc et al., 2002).
第十大簇 (#9) 的轮廓值为 0.994,由 38 个成员组成。 LLR 鉴定为铁氧化菌簇,LSI 鉴定为重金属簇,MI 鉴定为酸性矿排水簇。该集群与采矿活动对酸性矿山排水环境中微生物群落的影响有关。铁氧化相关细菌类群的鉴定是该簇的一项重大发现,在重金属污染处理的生物修复技术中具有潜在的应用前景。酸性矿山废水(AMD)是由硫化物矿物废石的化学和微生物氧化产生的,它是采矿活动的副产品( Leduc 等,2002 )。这些微生物已经发展出在极端酸性环境中繁衍生息的独特能力,它们对硫和铁生物地球化学循环的贡献是巨大的( Fashola等人,2015 )。然而,AMD由于极端的酸性、高浓度的重金属、盐度和三价铁沉淀而造成严重的环境问题,导致周围生物群的破坏( Leduc等,2002 )。
Timeline co-citation analysis of research documents on the impact of climate change on marine microbes reveals a number of prominent research areas, as indicated by the most frequently co-occurring keywords (Fig. 4). Among these, the five most significant clusters in recent years are the (#0) “coral microbiome”, (#2) “novel Thermoplasmatota clade”, (#3) “marine dinoflagellate bloom”, (#4) “human health”, and (#11) “antioxidant defense”. These clusters have become widely recognized hotspots of research in the realm of climate change and its effects on marine microbes. It is noteworthy that the rise of these particular topics has been driven by their immense impact, both ecologically and scientifically, and is reflective of the need for continued research in these areas.
对气候变化对海洋微生物影响的研究文献进行时间线共被引分析,揭示了一些突出的研究领域,如最常见的共现关键词所示(图4 )。其中,近年来最重要的五个集群是(#0)“珊瑚微生物组”、(#2)“新型热原体进化枝”、(#3)“海洋甲藻水华”、(#4)“人类健康” ,和(#11)“抗氧化防御”。这些集群已成为气候变化及其对海洋微生物影响领域广泛认可的研究热点。值得注意的是,这些特定主题的兴起是由它们在生态和科学上的巨大影响推动的,并且反映了在这些领域继续研究的需要。

4.2.2. Author networks collaboration, networks of institutions and countries
4.2.2.作者网络合作、机构和国家网络

By analyzing this network (i.e., author, institution and countries), we can better understand the complex and intricate collaborations and partnerships that drive progress in this field.
通过分析这个网络(即作者、机构和国家),我们可以更好地理解推动该领域进步的复杂而复杂的合作和伙伴关系。
The author network analysis revealed that five of the top ten most frequently cited authors were affiliated with Chinese academic institutions. Yue Zhang from the Chinese Academy of Sciences led the list with 16 records, followed by Li Yi from the Henan Normal University. The affiliation record count revealed that the Chinese Academy of Sciences and the University of California system had the highest affiliation records, with 239 and 155, respectively. Furthermore, the country network analysis data indicated that the USA has the highest record count, with 856, followed by China with 524, and Germany with 301.
作者网络分析显示,被引用次数排名前十位的作者中有五位来自中国学术机构。中国科学院的张悦以 16 项记录位居榜首,其次是河南师范大学的李毅。隶属记录计数显示,中国科学院和加州大学系统的隶属记录最高,分别为 239 条和 155 条。此外,国家网络分析数据显示,美国的记录数量最多,为 856 条,其次是中国,为 524 条,德国为 301 条。
The network of institutions analysis revealed that the Centre national de la recherche scientifique (CNRS) in France had the highest record count with 125, followed by the Helmholtz Association of German Research Centres with 121 and UDICE French Research Universities with 104. Additionally, the country network analysis indicated that the top five countries in terms of record count, namely the USA, China, Germany, Australia, and England, were affiliated with the top three institutions with the highest record count, indicating a correlation between institutional networks and research productivity.
机构网络分析显示,法国国家科学研究中心 (CNRS) 的记录数量最多,为 125 个,其次是亥姆霍兹德国研究中心协会 (121 个) 和 UDICE 法国研究大学 (104 个)。网络分析表明,记录数排名前五的国家,即美国、中国、德国、澳大利亚和英国,都隶属于记录数最多的前三名机构,这表明机构网络与研究生产力之间存在相关性。
Overall, the scientometric analysis has provided valuable insights into the collaborative efforts, and research productivity of the top cited authors and their affiliations, countries, and institutions. Further exploration of these key elements can help identify emerging research trends and potential hotspots of research in the field of climate change and marine microbes.
总体而言,科学计量分析为高被引作者及其所属机构、国家和机构的合作努力和研究生产力提供了宝贵的见解。对这些关键要素的进一步探索有助于识别气候变化和海洋微生物领域的新兴研究趋势和潜在研究热点。

4.2.3. Keywords Co-occurrences analysis
4.2.3.关键词共现分析

Cluster #0, comprising 115 members and displaying a silhouette value of 0.567, is characterized by LLR and LSI as microbial diversity and MI as microbial communities. The cluster is associated with the most frequently cited keywords “microbial community,” “dynamics,” “bacterial community,” “sea,” “ocean,” and “patterns.” This cluster is closely associated with Cluster #6, consisting of 56 members and exhibiting a silhouette value of 0.741; LLR identifies it as nitrification, LSI as anaerobic oxidation, and MI as microbial communities. The most frequently cited keywords in this cluster are “freshwater,” “denitrification,” “nitrification,” “sulfate-reducing bacteria,” and “community composition.” The identification of this cluster underscores the importance of investigating the complex and diverse nature of microbial communities in marine environments, including their crucial roles in biogeochemical cycling, nutrient cycling, and carbon fixation, among other processes (Arrigo, 2005). For instance, the filamentous cyanobacterium Trichodesmium spp. is widely recognized as the most dominant N2-fixing species in oligotrophic marine ecosystems (Carpenter & Romans, 1991; Karl et al., 1997). Recent discoveries have further augmented our understanding of this crucial biogeochemical cycle, including novel N2-fixing marine microorganisms and the widespread distribution of ammonia-oxidizing Thaumarchaeota in the ocean (Song et al., 2022). Changes in temperature, salinity, and nutrient availability due to climate change can significantly impact the rates of nitrification and anaerobic oxidation, leading to changes in the cycling of nitrogen and overall ecosystem functioning (Song et al., 2022). The microbial communities identified in this cluster play an integral role in maintaining the function of marine ecosystems. Thus, the identification and analysis of this cluster are fundamental to our comprehension of microbial community responses to climate change and their critical roles in the maintenance of ecosystem function.
簇 #0 由 115 个成员组成,轮廓值为 0.567,其特征为 LLR 和 LSI 为微生物多样性,MI 为微生物群落。该簇与最常被引用的关键词“微生物群落”、“动力学”、“细菌群落”、“海洋”、“海洋”和“模式”相关。该簇与簇 #6 密切相关,由 56 个成员组成,轮廓值为 0.741; LLR 将其识别为硝化作用,LSI 将其识别为厌氧氧化,MI 将其识别为微生物群落。该集群中最常被引用的关键词是“淡水”、“反硝化”、“硝化”、“硫酸盐还原菌”和“群落组成”。该簇的识别强调了研究海洋环境中微生物群落的复杂性和多样性的重要性,包括它们在生物地球化学循环、养分循环和碳固定等过程中的关键作用( Arrigo,2005 )。例如,丝状蓝藻Trichodesmium spp。被广泛认为是寡营养海洋生态系统中最主要的固氮物种( Carpenter & Romans,1991Karl et al.,1997 )。 最近的发现进一步增强了我们对这一重要生物地球化学循环的理解,包括新型固氮海洋微生物和氨氧化奇古菌在海洋中的广泛分布( Song等,2022 )。气候变化导致的温度、盐度和养分可用性的变化会显着影响硝化和厌氧氧化的速率,导致氮循环和整体生态系统功能的变化( Song等,2022 )。该簇中确定的微生物群落在维持海洋生态系统的功能方面发挥着不可或缺的作用。因此,对该簇的识别和分析对于我们理解微生物群落对气候变化的反应及其在维持生态系统功能中的关键作用至关重要。
Cluster #1, consisting of 78 members and demonstrating a silhouette value of 0.714, is labeled as ocean acidification, climate change, and microbial communities by LLR, LSI, and MI, respectively. The most commonly cited keywords under this cluster include “ocean acidification,” “Escherichia coli,” “eutrophication,” “water quality,” and “pollution.” The cluster emphasizes the alterations in microbial communities brought about by the increase in acidity levels in seawater due to the rise in carbon dioxide absorption. Human activities, such as the discharge of untreated waste, agricultural run-off, and other sources of pollution, can also contribute to increased acidity levels in ocean water (Kuffner et al., 2008; Duarte et al., 2013). The microbial communities identified in this cluster play an essential role in maintaining the water quality of marine ecosystems, underscoring the importance of investigating the impacts of climate change on microbial communities in marine environments.
簇#1 由 78 个成员组成,轮廓值为 0.714,分别被 LLR、LSI 和 MI 标记为海洋酸化、气候变化和微生物群落。该簇下最常被引用的关键词包括“海洋酸化”、“大肠杆菌”、“富营养化”、“水质”和“污染”。该集群强调了由于二氧化碳吸收增加而导致海水酸度增加所带来的微生物群落的变化。人类活动,例如排放未经处理的废物、农业径流和其他污染源,也会导致海水酸度水平升高( Kuffner 等,2008Duarte 等,2013 )。该集群中确定的微生物群落在维持海洋生态系统的水质方面发挥着重要作用,强调了研究气候变化对海洋环境中微生物群落影响的重要性。
Cluster #2, with 64 members and a silhouette value of 0.776, is characterized by LLR as bacteria characteristics, LSI as microbial diversity, and MI as microbial communities. The most cited keywords associated with this cluster include “bacteria,” “community structure,” “populations,” “antibiotic resistance,” and “environment.” Identifying bacterial populations and their characteristics within this cluster is crucial for comprehending the impact of environmental changes on microbial communities. This cluster elucidates microbial community adaptation, including antibiotic resistance development in marine bacteria. Antibiotics in aquaculture can induce resistance in column water, sediment, and fish-associated bacterial strains due to horizontal gene transfer and mobile resistance genes (Di Cesare et al., 2013). This transfer facilitates resistance spread from aquatic microbial communities to human pathogens, compromising antibiotic effectiveness for human health. Studies have suggested that temperature increases caused by climate change can trigger antibiotic resistance, thereby further exacerbating the problem (Erauso et al., 2011; Pepi & Focardi, 2021).
簇#2 有 64 个成员,轮廓值为 0.776,其特征为 LLR 为细菌特征、LSI 为微生物多样性、MI 为微生物群落。与该集群相关的被引用最多的关键词包括“细菌”、“群落结构”、“种群”、“抗生素耐药性”和“环境”。识别该簇内的细菌种群及其特征对于理解环境变化对微生物群落的影响至关重要。该簇阐明了微生物群落的适应,包括海洋细菌中抗生素耐药性的发展。由于水平基因转移和移动抗性基因,水产养殖中的抗生素可诱导柱水、沉积物和鱼类相关菌株产生抗性( Di Cesare 等,2013 )。这种转移促进了耐药性从水生微生物群落向人类病原体的传播,从而损害了抗生素对人类健康的有效性。研究表明,气候变化引起的气温升高会引发抗生素耐药性,从而进一步加剧这一问题( Erauso 等,2011Pepi 和 Focardi,2021 )。
Cluster #3, comprising 64 members and exhibiting a silhouette value of 0.724, is identified by LLR as carbon, LSI as bioremediation, and MI as microbial communities. The most frequently cited keywords under this cluster include “carbon,” “growth,” “nitrogen,” “degradation,” “oxidation,” and “reduction.” This cluster has a close association with Cluster #8, which focuses on the study of novel bacterial species and their potential roles in biodegradation and microbial diversity in aquatic environments. The most cited keywords (“sediment”, “water”, “sp. Nov”, “biodegradation”, “bacterial diversity”, and “marine bacteria”), in these cluster emphasize the carbon cycle, pollutant degradation, and the discovery of new bacterial taxa in marine ecosystems. Marine microbes are integral to the carbon cycle, as they decompose organic matter and convert it into carbon dioxide, subsequently released into the atmosphere (Worden et al., 2015; Moran et al., 2022). Alterations in ocean temperature and pH levels can influence the carbon cycle by affecting the activity of microbial communities involved in carbon cycling processes (Smith et al., 2009). Bioremediation, which employs microbial communities to remediate contaminated environments, is a crucial aspect of this research area (Mohanrasu et al., 2020). Identifying microbial communities proficient in degrading pollutants, such as hydrocarbons, is essential for comprehending the role of microbes in preserving marine ecosystem health. Consequently, pertinent studies in this field examine the degradation of pollutants by microbial communities and the impacts of climate change on both the carbon cycle and microbial communities within marine environments.
簇 #3 由 64 个成员组成,轮廓值为 0.724,被 LLR 识别为碳,LSI 识别为生物修复,MI 识别为微生物群落。该簇下最常被引用的关键词包括“碳”、“生长”、“氮”、“降解”、“氧化”和“还原”。该簇与簇 #8 密切相关,簇#8 侧重于研究新型细菌物种及其在水生环境中生物降解和微生物多样性中的潜在作用。这些簇中被引用最多的关键词(“沉积物”、“水”、“sp. Nov”、“生物降解”、“细菌多样性”和“海洋细菌”)强调碳循环、污染物降解和发现海洋生态系统中的新细菌类群。海洋微生物是碳循环不可或缺的一部分,因为它们分解有机物并将其转化为二氧化碳,随后释放到大气中( Worden 等人,2015Moran 等人,2022 )。海洋温度和 pH 值的变化可以通过影响参与碳循环过程的微生物群落的活动来影响碳循环 Smith 等,2009 )。生物修复利用微生物群落来修复受污染的环境,是该研究领域的一个重要方面( Mohanrasu 等人,2020 )。识别能够降解碳氢化合物等污染物的微生物群落对于理解微生物在保护海洋生态系统健康中的作用至关重要。 因此,该领域的相关研究考察了微生物群落对污染物的降解以及气候变化对海洋环境中碳循环和微生物群落的影响。
Cluster #4, which contains 64 members and has a silhouette value of 0.737, is identified as organic matter by LLR, nitrogen fixation by LSI, and microbial communities by MI. Frequently cited keywords in this cluster include “phytoplankton,” “organic matter,” “climate,” “phosphorus,” “metabolism,” and “nitrogen fixation.” Identifying this cluster is crucial for understanding the interplay between organic matter and nitrogen fixation in marine environments, especially in the context of climate change. Organic matter and nitrogen are essential for the growth and survival of marine microbes, including phytoplankton, which constitute the foundation of the marine food web (Trombetta et al., 2020). Variations in temperature and nutrient availability can affect the equilibrium between phytoplankton and other microbial communities, resulting in alterations to the overall structure and function of marine ecosystems (Moloney et al., 2011). The significance of this cluster to the impact of climate change on marine microbes is underscored by the inclusion of keywords like “climate” and “phosphorus,” which are vital determinants of microbial community dynamics in marine ecosystems. Relevant studies in this field explore the effects of temperature and nutrient availability on marine microbes' growth and metabolism and examine the role of nitrogen fixation in sustaining the health and productivity of marine ecosystems.
簇#4 包含 64 个成员,轮廓值为 0.737,通过 LLR 识别为有机物,通过 LSI 识别为固氮,通过 MI 识别为微生物群落。该簇中经常被引用的关键词包括“浮游植物”、“有机物”、“气候”、“磷”、“代谢”和“固氮”。识别这个簇对于理解海洋环境中有机物和固氮之间的相互作用至关重要,特别是在气候变化的背景下。有机物和氮对于包括浮游植物在内的海洋微生物的生长和生存至关重要,它们构成了海洋食物网的基础( Trombetta et al., 2020 )。温度和养分有效性的变化会影响浮游植物和其他微生物群落之间的平衡,从而导致海洋生态系统整体结构和功能的改变( Moloney等,2011 )。该集群对气候变化对海洋微生物影响的重要性通过包含“气候”和“磷”等关键词来强调,这些关键词是海洋生态系统微生物群落动态的重要决定因素。该领域的相关研究探讨了温度和养分有效性对海洋微生物生长和代谢的影响,并探讨了固氮在维持海洋生态系统健康和生产力中的作用。
Cluster #5, containing 59 members and exhibiting a silhouette value of 0.797, is identified by LLR as salinity stress, LSI as climate change, and MI as microbial growth. The most frequently cited keywords under this cluster include “diversity,” “climate change,” “soil,” “salinity,” “responses,” “impact,” and “drought.” Salinity, a key environmental factor, influences microbial community distribution and abundance in marine ecosystems. Climate change-induced salinity alterations can impact diversity, function, biogeochemical cycling, and ecosystem dynamics (Kiene et al., 2000). Identifying salinity-resilient communities is crucial for understanding adaptive capacity under changing conditions (Ishii et al., 2015). Relevant studies in this field include those investigating the response of microbial communities to salinity stress and the impact of salinity stress on biogeochemical cycling in marine ecosystems (Li et al., 2022).
簇 #5 包含 59 个成员,轮廓值为 0.797,LLR 识别为盐度胁迫,LSI 识别为气候变化,MI 识别为微生物生长。该组下最常被引用的关键词包括“多样性”、“气候变化”、“土壤”、“盐度”、“响应”、“影响”和“干旱”。盐度是一个关键的环境因素,影响海洋生态系统中微生物群落的分布和丰度。气候变化引起的盐度变化会影响多样性、功能、生物地球化学循环和生态系统动态( Kiene et al., 2000 )。识别盐度恢复能力的群落对于了解变化条件下的适应能力至关重要( Ishii et al., 2015 )。该领域的相关研究包括微生物群落对盐度胁迫的响应以及盐度胁迫对海洋生态系统生物地球化学循环的影响( Li等,2022 )。
Cluster #7 reveals important aspects of marine microbial communities that are crucial in the context of climate change. This cluster is primarily associated with the marine environment and is marked by the highest density of publications concerning the marine ecosystem. Specifically, this cluster is linked to the coral microbiome and highlights the microbial diversity within coral reefs, an essential component of the marine ecosystem. The significance of the coral microbiome is exemplified in its ability to contribute to the adaptation of corals in response to environmental stressors such as climate change (Epstein et al., 2019). Furthermore, this cluster is associated with organic carbon cycling and microbial biomass, which play a critical role in the regulation of biogeochemical cycles in the ocean. This cluster reveals the essential link between the marine microbial community and the overall health of the marine ecosystem, indicating the importance of studying marine microbes in the context of climate change (Sweet & Bulling, 2017).
集群 #7 揭示了海洋微生物群落的重要方面,这些方面在气候变化的背景下至关重要。该集群主要与海洋环境相关,其特点是有关海洋生态系统的出版物密度最高。具体来说,该簇与珊瑚微生物组相关,并突出了珊瑚礁内的微生物多样性,珊瑚礁是海洋生态系统的重要组成部分。珊瑚微生物组的重要性体现在它有助于珊瑚适应气候变化等环境压力因素的能力( Epstein 等,2019 )。此外,该簇与有机碳循环和微生物量有关,在海洋生物地球化学循环的调节中发挥着关键作用。该簇揭示了海洋微生物群落与海洋生态系统整体健康之间的重要联系,表明在气候变化背景下研究海洋微生物的重要性( Sweet&Bulling,2017 )。
Cluster #9, the 10th largest cluster, comprises 50 members and has a silhouette value of 0.796. This cluster is labeled as 16s rRNA by LLR, microbial communities by LSI, and microbial communities (0.47) by MI. The most cited keywords in this cluster are “microorganisms”, “accumulation”, “16s rRNA”, “sequences”, “resistance”, and “calcification”. 16s rRNA sequencing is a powerful tool for identifying bacterial communities in marine environments, providing a comprehensive view of the diversity of microbial life in the ocean (Valenzuela-González et al., 2015; Liu et al., 2019; Willis et al., 2019). This cluster focuses on the study of microorganisms, their accumulation and resistance, and their impact on calcification. These microorganisms play an essential role in biogeochemical cycles, controlling nutrient fluxes and carbon storage in the ocean. The findings in this cluster highlight the potential use of 16s rRNA sequencing to assess the effects of climate change on microbial communities and calcification in marine environments.
聚类 #9 是第 10 大聚类,包含 50 个成员,轮廓值为 0.796。该簇被 LLR 标记为 16s rRNA,被 LSI 标记为微生物群落,被 MI 标记为微生物群落 (0.47)。该簇中被引用最多的关键词是“微生物”、“积累”、“16s rRNA”、“序列”、“抵抗”和“钙化”。 16s rRNA 测序是识别海洋环境中细菌群落的强大工具,可全面了解海洋微生物生命的多样性( Valenzuela-González 等,2015Liu 等,2019Willis 等, 2019 )。该集群重点研究微生物、微生物的积累和抵抗力,以及它们对钙化的影响。这些微生物在生物地球化学循环中发挥着重要作用,控制海洋中的营养通量和碳储存。该组的研究结果强调了 16s rRNA 测序可用于评估气候变化对海洋环境中微生物群落和钙化的影响的潜在用途。
The keyword timeline analysis (Fig. 7) provides an understanding of the research topics that have been popular in the field of marine microbial studies over the years. The major keywords from 1990 to 2000 included “sediment”, “biodegradation”, “carbon”, “phytoplankton”, “biomass”, and “assemblages”. This was followed by the evolution of major keywords from 2000 to 2010, which included “organic matter”, “dynamics”, “diversity”, “evolution”, “salinity”, and “climate change”.
关键词时间轴分析(图7 )提供了对多年来海洋微生物研究领域流行的研究主题的了解。 1990年至2000年的主要关键词包括“沉积物”、“生物降解”、“碳”、“浮游植物”、“生物质”和“组合物”。接下来是2000年至2010年主要关键词的演变,包括“有机物”、“动力学”、“多样性”、“进化”、“盐度”和“气候变化”。
The final decade, from 2010 to 2022, saw a shift in research themes, with an increase in the frequency of keywords such as “ocean acidification”, “nitrification”, “nitrogen fixation”, “biogeography”, “resistance”, “mechanisms”, “drought”, “tolerance”, “salt stress”, and “microbiome”. The increase in the frequency of these keywords suggests that studies on the impact of climate change on marine microbial communities have become more specific and focused. The identification of emerging research themes is essential for predicting and addressing future challenges in the field. Overall, this figure provides valuable insights into the trends and evolution of research topics in marine microbial studies with respect to climate change.
最后十年,从2010年到2022年,研究主题发生了转变,“海洋酸化”、“硝化”、“固氮”、“生物地理学”、“抵抗”、“机制”等关键词出现的频率有所增加。 ”、“干旱”、“耐受性”、“盐胁迫”和“微生物组”。这些关键词出现频率的增加表明,气候变化对海洋微生物群落影响的研究变得更加具体和集中。确定新兴研究主题对于预测和应对该领域未来的挑战至关重要。总体而言,该图为有关气候变化的海洋微生物研究主题的趋势和演变提供了有价值的见解。

5. Emerging hotspots 5.新兴热点

Scientometrics investigates the quantitative aspects of scientific research, assessing the influence of scientific contributions and identifying research trends. This study provides a comprehensive overview of the recent research directions in the area of climate change's impact on marine microbes, as well as the subsequent effects on marine ecosystems and human health. Understanding that researchers may be guided by their unique experiences and interests, this review highlights several emerging research hotspots for further investigation which includes examining the coral microbiome and its relation to climate change's impact on marine microbes, the growing interest in the novel Thermoplasmatota clade, the vital role played by marine dinoflagellate blooms, the crucial intersection between human health and marine microbes, and recent scientific discoveries pertaining to antioxidant defense mechanisms in the marine environment.
科学计量学研究科学研究的定量方面,评估科学贡献的影响并确定研究趋势。本研究全面概述了气候变化对海洋微生物的影响以及对海洋生态系统和人类健康的后续影响领域的最新研究方向。了解研究人员可能会受到他们独特的经验和兴趣的指导,这篇综述强调了几个需要进一步研究的新兴研究热点,包括检查珊瑚微生物组及其与气候变化对海洋微生物影响的关系、对新型热原体进化枝日益增长的兴趣、海洋甲藻大量繁殖所发挥的重要作用、人类健康与海洋微生物之间的重要交叉点,以及有关海洋环境中抗氧化防御机制的最新科学发现。

5.1. Coral microbiome - linking the impact of climate change on marine microbes
5.1.珊瑚微生物组 - 将气候变化对海洋微生物的影响联系起来

The coral microbiome is a complex system that involves various microorganisms such as dinoflagellates, viruses, fungi, archaea, and bacteria (Huggett & Apprill, 2019; van Oppen and Blackall, 2019). While most research has centered around bacteria, the coral microbiome harbours other microorganisms that have received comparatively little attention but are known to form associations with coral. Among these microorganisms, archaea are considered minor yet functionally essential components that contribute to nutrient recycling for the host (van Oppen and Blackall, 2019). For example, the Thermoproteota archaebacteria have been reported to play a significant role in nitrification, denitrification, and ammonia oxidation (Wegley et al., 2007). Corals form a holobiont, including the coral animal, endosymbiotic algae (genus Symbiodinium) (Rohwer et al., 2002), and microorganisms. Microbial communities play a crucial role in acclimatising the coral holobiont to environmental changes through rapid community restructuring (Torda et al., 2017a, Torda et al., 2017b). This alliance enables corals to colonize a wide range of marine habitats and construct large reef structures (Rosenberg et al., 2007; Dunphy et al., 2019).
珊瑚微生物组是一个复杂的系统,涉及多种微生物,如甲藻、病毒、真菌、古细菌和细菌( Huggett & Apprill,2019van Oppen 和 Blackall,2019 )。虽然大多数研究都以细菌为中心,但珊瑚微生物组中还存在其他微生物,这些微生物受到的关注相对较少,但已知与珊瑚形成关联。在这些微生物中,古细菌被认为是次要但功能必需的成分,有助于宿主的营养循环( van Oppen 和 Blackall,2019 )。例如, Thermoproteota古细菌已被报道在硝化、反硝化和氨氧化中发挥重要作用( Wegley 等,2007 )。珊瑚形成一个全生物体,包括珊瑚动物、内共生藻类(共生藻属)( Rohwer et al., 2002 )和微生物。微生物群落通过快速群落重组,在珊瑚全生物适应环境变化方面发挥着至关重要的作用( Torda 等,2017aTorda 等,2017b )。 这种联盟使珊瑚能够在广泛的海洋栖息地中定居并建造大型珊瑚礁结构( Rosenberg 等人,2007 年Dunphy 等人,2019 年)。
Understanding the stability of host-microbial interactions is crucial to comprehending coral-microbial symbiosis. This is particularly relevant as breakdowns in this relationship, such as disease outbreaks, have been linked to significant declines in coral cover globally, leading to a shift towards algae-dominated systems (Rosenberg et al., 2007; Dunphy et al., 2019). The symbiotic relationship within the coral holobiont is susceptible to environmental and climate changes. Changes in environmental conditions and anthropogenic activities, such as nutrient input and salinity, can influence the microbial communities associated with corals (Lima et al., 2020), resulting in alterations in the taxonomic and functional composition of the coral microbiome (Furby et al., 2014; Garren et al., 2009; Meron et al., 2011). Temperature and pH changes in marine environments also significantly impact the coral microbiome (Meron et al., 2011), ultimately leading to coral disease and mortality.
了解宿主-微生物相互作用的稳定性对于理解珊瑚-微生物共生至关重要。这尤其重要,因为这种关系的破裂,例如疾病爆发,与全球珊瑚覆盖率的显着下降有关,导致向藻类为主的系统的转变( Rosenberg等人,2007年Dunphy等人,2019年) 。珊瑚全生物内的共生关系容易受到环境和气候变化的影响。环境条件和人类活动的变化,例如养分输入和盐度,可以影响与珊瑚相关的微生物群落( Lima等人,2020 ),导致珊瑚微生物组的分类和功能组成发生变化( Furby等人,2020)。 ,2014Garren 等,2009Meron 等,2011 )。海洋环境中的温度和 pH 值变化也显着影响珊瑚微生物群( Meron 等,2011 ),最终导致珊瑚疾病和死亡。
For example, the effects of thermal stress and ocean acidification on the microbiome of the Caribbean barrel sponge, Xestospongia muta, have been observed to have significant impacts (Lesser et al., 2016). The study found that pH alone increased inter-individual variation in sponge microbiomes, while the elevated temperature alone treatment reduced this variation. Similarly, Morrow et al. (2015) reported an increase in the abundance of sponges with photoautotrophic symbionts (such as Synechococcus sp.) in the absence of elevated seawater temperature. It was suggested that this was due to the symbiotic cyanobacteria conferring varying abilities to translocate photo-autotrophically derived organic products to the host (Fiore et al., 2013). When exposed to elevated pCO2 alone, cyanobacteria abundance was found to increase significantly, with photosynthesis predicted to be their most important functional role (Morrow et al., 2015). In another comprehensive study, Webster et al. (2016) investigated the microbiome response of multiple marine organisms to near-future climate change conditions. All taxa were tolerant of elevated pCO2/reduced pH, maintaining stable microbial communities between pH 8.1 and 7. However, the microbial communities of Crustose coralline algae (CCA) and foraminifera were sensitive to elevated seawater temperature, with a significant microbial shift occurring between 28 °C and 31 °C, respectively, involving the loss of specific taxa and the appearance of novel microbial groups.
例如,据观察,热应力和海洋酸化对加勒比桶形海绵Xestospongia muta的微生物组产生了重大影响( Lesser 等,2016 )。研究发现,单独的 pH 值会增加海绵微生物组的个体间差异,而单独的升高温度处理会减少这种差异。同样,莫罗等人。 (2015)报道称,在海水温度不升高的情况下,具有光合自养共生体(例如聚球藻)海绵数量增加。有人认为,这是由于共生蓝藻赋予了不同的能力,将光自养衍生的有机产物转移到宿主上( Fiore 等人,2013 )。当单独暴露于升高的 pCO 2,蓝藻丰度被发现显着增加,光合作用预计是它们最重要的功能作用( Morrow et al., 2015 )。在另一项综合研究中,韦伯斯特等人。 (2016)研究了多种海洋生物对近期气候变化条件的微生物组反应。所有类群都能耐受 pCO 2升高/pH 降低,从而在 pH 8.1 至 7 之间维持稳定的微生物群落。 然而,甲壳珊瑚藻 (CCA) 和有孔虫的微生物群落对海水温度升高敏感,在 28 °C 和 31 °C 之间分别发生显着的微生物转变,包括特定类群的丧失和新型微生物的出现。组。
Recent studies have demonstrated the potential for microbiome engineering to improve the resilience of corals to climate change, which could have far-reaching implications for coral reef restoration and management (Damjanovic et al., 2017; Epstein et al., 2019). One of the earliest successful coral microbiome manipulation experiments involved investigating the possibility of increasing the resistance of corals to oil pollution through microbial inoculation (dos Santos et al., 2015). Other research has begun to explore using heat-selected members of the Symbiodiniaceae or bacterial communities from “donor” heat-resistant corals as microbial inoculants to increase coral resilience to thermal stress (Chakravarti et al., 2017; Damjanovic et al., 2017). Therefore, the intricate nature of the coral microbiome highlights the need for in-depth studies to understand better the various microorganisms that contribute to the holobiont's overall health and functioning.
最近的研究表明,微生物组工程具有提高珊瑚对气候变化的适应能力的潜力,这可能对珊瑚礁的恢复和管理产生深远的影响( Damjanovic 等,2017Epstein 等,2019 )。最早成功的珊瑚微生物组操纵实验之一涉及研究通过微生物接种提高珊瑚对石油污染的抵抗力的可能性( dos Santos 等,2015 )。其他研究已开始探索使用共生科的热选择成员或来自“供体”耐热珊瑚的细菌群落作为微生物接种剂,以提高珊瑚对热应激的恢复能力( Chakravarti 等人,2017 年Damjanovic 等人,2017 年) 。因此,珊瑚微生物组的复杂性凸显了深入研究的必要性,以更好地了解有助于全生物整体健康和功能的各种微生物。

5.2. Increasing interest in novel Thermoplasmatota clade
5.2.对新型热原体进化枝的兴趣日益浓厚

Thermoplasmatota clade marine microbes are a diverse group of microorganisms that have garnered increasing interest in the field of microbiology. These microbes are characterized by their unique morphology and metabolic features, which make them ideally suited to living in extreme environments such as hydrothermal vents, acidic pH levels (Huang et al., 2021), high salt concentrations, acetate assimilation (Seyler et al., 2014) and deep-sea sediments (Rinke et al., 2019; Zheng et al., 2022). Their ability to thrive in extreme conditions has led to a growing interest in their potential applications in biotechnology and bioremediation (Yang et al., 2022). Moreover, recent studies have suggested that Thermoplasmatota clade marine microbes may play a key role in global biogeochemical cycles, particularly in the context of climate change (Li et al., 2022).
热原体进化枝海洋微生物是一个多样化的微生物群,在微生物学领域引起了越来越多的兴趣。这些微生物具有独特的形态和代谢特征,这使得它们非常适合生活在极端环境中,例如热液喷口、酸性pH水平( Huang等,2021 )、高盐浓度、醋酸同化( Seyler等,2021)。 ,2014 )和深海沉积物( Rinke等,2019Zheng等,2022 )。它们在极端条件下茁壮成长的能力导致人们对其在生物技术和生物修复中的潜在应用越来越感兴趣( Yang et al., 2022 )。此外,最近的研究表明,热原体进化枝海洋微生物可能在全球生物地球化学循环中发挥关键作用,特别是在气候变化的背景下( Li et al., 2022 )。
Archaea, once thought of as obligate extremophiles, have been recognized as ubiquitous and abundant constituents of the marine microbial community. Marine archaea can be classified into three major lineages: Marine Group I (MGI) thaumarchaeota, Marine Group II (MGII) thermoplasmatota, and Marine Group III (MGIII) thermoplasmatota, a recently proposed phylum (Rinke et al., 2019; Jain and Krishnan, 2021). MGII can be further divided into two subgroups, IIa and IIb (Galand et al., 2010). MGII archaea are commonly found in the photic zone, although their abundance is lower in deep-sea habitats. They show pronounced spatial and seasonal variation in their distribution and are found globally, even in polar regions (Zhang et al., 2015; Rinke et al., 2019). Genome predictions suggest that MGII are motile photoheterotrophs that are capable of breaking down proteins and lipids, indicating organic particles are crucial for their growth (Iverson et al., 2012; Rinke et al., 2019).
古细菌曾经被认为是专性极端微生物,现已被认为是海洋微生物群落中普遍存在且丰富的组成部分。海洋古菌可分为三个主要谱系:海洋 I 类 (MGI)奇古菌门、海洋 II 类 (MGII) 热原体门和海洋 III 类 (MGIII) 热原体门,这是最近提出的一个门( Rinke 等人,2019Jain 和 Krishnan) ,2021 )。 MGII可进一步分为两个亚组,IIa和IIb( Galand等,2010 )。 MGII 古菌常见于透光区,但在深海生境中其丰度较低。它们的分布表现出明显的空间和季节变化,在全球范围内都有发现,甚至在极地地区也有分布( Zhang et al., 2015Rinke et al., 2019 )。基因组预测表明,MGII 是能动的光异养生物,能够分解蛋白质和脂质,这表明有机颗粒对其生长至关重要( Iverson 等,2012Rinke 等,2019 )。
Despite these findings, cultivability remains a significant challenge. No successful cultivation of thermoplasmatota from the ocean has been achieved to date (Swan et al., 2014; Jain and Krishnan, 2021). Therefore, gaining a deeper understanding of these microorganisms and their ecological roles is crucial for advancing our understanding of Earth's ecosystems and the impacts of climate change.
尽管有这些发现,可栽培性仍然是一个重大挑战。迄今为止,尚未成功从海洋中培养热原体( Swan 等人,2014 年Jain 和 Krishnan,2021 年)。因此,更深入地了解这些微生物及其生态作用对于增进我们对地球生态系统和气候变化影响的理解至关重要。

5.3. Crucial role of a marine dinoflagellate bloom
5.3.海洋甲藻爆发的关键作用

Marine dinoflagellate blooms are a natural phenomenon that occurs in the marine environment. Studies have demonstrated that the marine dinoflagellate bloom is connected to microbial communities and climate change. Changes in environmental factors, including temperature and nutrient availability, are known to alter microbial community composition, which in turn can lead to dinoflagellate blooms (Rooney-Varga et al., 2005). Furthermore, changes in the timing and magnitude of these blooms can have far-reaching impacts on marine ecosystems, including harmful effects on both the ecosystem and human health.
海洋甲藻大量繁殖是海洋环境中发生的自然现象。研究表明,海洋甲藻大量繁殖与微生物群落和气候变化有关。已知环境因素的变化,包括温度和养分可用性,会改变微生物群落组成,进而导致甲藻大量繁殖( Rooney-Varga 等,2005 )。此外,这些水华的时间和程度的变化可能会对海洋生态系统产生深远的影响,包括对生态系统和人类健康产生有害影响。
Microbial communities, particularly bacterial taxa, have been demonstrated to play a crucial role in regulating harmful algal blooms (HABs) (Zhang et al., 2018; Zhou et al., 2020). This can be attributed to various factors, including microbial mediation of biogeochemical cycling, micro food web structure, matter transformation, and alga-bacterium signaling regulation, such as quorum sensing (Zhou et al., 2016; Zhou et al., 2020).
微生物群落,特别是细菌类群,已被证明在调节有害藻华(HAB)方面发挥着至关重要的作用( Zhang et al., 2018Zhou et al., 2020 )。这可以归因于多种因素,包括生物地球化学循环的微生物介导、微食物网结构、物质转化和藻类信号调节,例如群体感应 Zhou et al., 2016Zhou et al., 2020 )。
Understanding the bacterial taxa associated with marine dinoflagellate blooms is crucial for developing innovative and efficient management strategies. Marine bacteria play a crucial role in either stimulating or inhibiting the growth of phytoplankton, disrupting their physiology, or even causing their demise. Research suggests that bacterial-mediated processes like biodegradation, alga-bacterium signaling regulation, and matter transformation could be the key to successful bloom management (Ferrier et al., 2002; Yoshinaga et al., 1997; Rooney-Varga et al., 2005; Furuki and Kobayashi, 1991).
了解与海洋甲藻水华相关的细菌分类群对于制定创新和有效的管理策略至关重要。海洋细菌在刺激或抑制浮游植物生长、破坏其生理、甚至导致其死亡方面发挥着至关重要的作用。研究表明,生物降解、藻类细菌信号调节和物质转化等细菌介导的过程可能是水华管理成功的关键( Ferrier 等人,2002 年Yoshinaga 等人,1997 年Rooney-Varga 等人,2005 年)古木和小林,1991 )。
During harmful algal bloom events, the bacterial communities in marine environments can exhibit a wide variety of structures, which can fluctuate throughout the bloom's duration. This variability can be influenced by various factors, including algal species, environmental conditions, and biological interactions (Zhu et al., 2019). The reasons behind these changes are due to the release of various low-molecular-weight (LMW) molecules by the algae, such as amino acids, organic acids, and carbohydrates, during the early stages of the blooms. Higher-molecular-weight (HMW) macromolecules like nucleic acids, polysaccharides, lipids, and proteins are released as the blooms progress. The shift in the concentration and ratio of LMW to HMW molecules can have an impact on the composition of free-living and attached bacterial communities (Zhu et al., 2019). In a study by Zhu et al. (2019), microbial populations were analyzed at different stages of a Scrippsiella trochoidea dinoflagellate bloom, including pre-bloom, during-bloom, and post-bloom. Results showed that Rhodobacterales, Bacteroidetes, Rhodospirillales, Flavobacteriales, and Pseudomonadales were the most abundant bacterial taxa during the bloom.
在有害的藻华事件期间,海洋环境中的细菌群落可能表现出多种结构,这些结构可能在藻华持续期间发生波动。这种变异性可能受到多种因素的影响,包括藻类种类、环境条件和生物相互作用( Zhu et al., 2019 )。这些变化背后的原因是藻类在水华早期阶段释放各种低分子量(LMW)分子,如氨基酸、有机酸和碳水化合物。随着花朵的生长,核酸、多糖、脂质和蛋白质等较高分子量 (HMW) 大分子会被释放。 LMW 与 HMW 分子的浓度和比例的变化可能会对自由生活和附着细菌群落的组成产生影响( Zhu et al., 2019 )。在朱等人的一项研究中。 (2019) ,对Scrippsiella trochoidea甲藻水华不同阶段的微生物种群进行了分析,包括水华前、水华期间和水华后。结果表明,红杆菌目拟杆菌目红螺菌目黄杆菌目假单胞菌目是水华期间最丰富的细菌类群。
The identification of microbial communities as potential biocontrol agents for harmful algal blooms offers promise in the context of climate change (Yoshinaga et al., 1995). For example, Fukami et al. (1991) observed that naturally occurring bacterial communities collected during a Gymnodinium nagasakiense bloom could inhibit Skeletonema costatum but stimulate G. nagasakiense. Subsequently, Flavobacterium sp. were found to have algicidal properties against G. nagasakiense, while having no effect on Chattonella antiqua, Heterosigma akashiwo, or S. costatum (Fukami et al., 1992). These findings suggest that there are species-specific interactions between bacteria and phytoplankton.
将微生物群落确定为有害藻类大量繁殖的潜在生物防治剂,为气候变化的背景带来了希望( Yoshinaga 等,1995 )。例如, Fukami 等人。 (1991)观察到,在长崎裸甲藻开花期间收集的自然存在的细菌群落可以抑制中肋骨条藻,但刺激长崎裸甲藻。随后,黄杆菌属。被发现对G. nagasakiense具有杀藻特性,而对Chattonella antiquaHeterosigma akashiwoS. costatum没有作用( Fukami 等,1992 )。这些发现表明细菌和浮游植物之间存在物种特异性的相互作用。
In summary, the relationship between marine dinoflagellate blooms, microbial communities, and climate change is complex and an evolving area of research. By identifying specific bacterial taxa associated with harmful algal blooms, researchers can develop novel strategies for their management, offering promise in the face of the growing threat of climate change. A deeper understanding of the microbial communities involved in these blooms and their response to changing environmental conditions is essential for the continued preservation of marine ecosystems.
总之,海洋甲藻大量繁殖、微生物群落和气候变化之间的关系是复杂的,并且是一个不断发展的研究领域。通过识别与有害藻华相关的特定细菌类群,研究人员可以制定新的管理策略,为应对日益严重的气候变化威胁提供希望。更深入地了解参与这些水华的微生物群落及其对不断变化的环境条件的反应对于持续保护海洋生态系统至关重要。

5.4. Human health - a vital scientific discussion
5.4.人类健康——重要的科学讨论

Marine microbial diversity is extensive, with various physiological adaptations for survival in the oceanic environment (Waters et al., 2010; Dewapriya and Kim, 2014). These adaptations have enabled marine microorganisms to produce distinctive microbial metabolites (Egan et al., 2008). Additionally, marine microorganisms exhibit metabolic efficiency and have evolved effective mechanisms to utilize meagre dissolved organic matter to produce more metabolites than the energy consumed (Moran and Miller, 2007).
海洋微生物多样性广泛,具有在海洋环境中生存的各种生理适应能力( Waters 等,2010Dewapriya 和 Kim,2014 )。这些适应使海洋微生物能够产生独特的微生物代谢物( Egan 等,2008 )。此外,海洋微生物表现出代谢效率,并已进化出有效的机制,利用微量溶解的有机物产生比消耗的能量更多的代谢物( Moran 和 Miller,2007 )。
The potential of marine microbes as sources of bioactive metabolites has garnered increasing attention in recent years, with significant implications for the development of marine natural products in clinical trials (Waters et al., 2010). Among molecules in the clinical pipeline derived from bacteria or likely produced by bacteria (Waters et al., 2010) are compounds such as soblidotin and tasidotin, which are produced by cyanobacteria in the Lyngbya and Symploca genera (Harrigan et al., 1998). Additionally, Salinosporamide A is produced by the marine actinomycete Salinispora tropica (Davidson et al., 2001), while bryostatin, initially thought to be produced by the host organisms (bryozoan), is now widely accepted to be produced by the uncultured symbiotic bacteria, ‘Candidatus Endobugula sertula’ (Trindade-Silva et al., 2010).
近年来,海洋微生物作为生物活性代谢物来源的潜力引起了越来越多的关注,这对临床试验中海洋天然产物的开发具有重要意义( Waters等,2010 )。临床管道中源自细菌或可能由细菌产生的分子( Waters 等,2010 )包括 soblidotin 和 tasidotin 等化合物,它们是由LyngbyaSymploca属的蓝细菌产生的( Harrigan 等,1998 )。此外, Salinosporamide A是由海洋放线菌Salinispora tropica产生的( Davidson等,2001 ),而苔藓抑素最初被认为是由宿主生物(苔藓虫)产生的,现在被广泛认为是由未培养的共生细菌产生的, “ Candidatus Endobugula sertula ”( Trindade-Silva 等人,2010 )。
The impacts of climate change on marine ecosystems, particularly on microbial communities that underpin their functioning, have significant implications for human health. Rising sea temperatures, ocean acidification, and changes in nutrient availability are altering the composition and metabolic activity of marine microbes, with potential consequences for human health.
气候变化对海洋生态系统的影响,特别是对支撑其功能的微生物群落的影响,对人类健康具有重大影响。海水温度上升、海洋酸化和营养物质供应的变化正在改变海洋微生物的组成和代谢活动,对人类健康产生潜在影响。
According to Mora et al. (2022), climate hazards have exacerbated 58% (218 out of 375) of infectious diseases affecting human populations worldwide. For example, heatwaves have been linked to an increase in recreational water-related activities and a corresponding rise in several waterborne diseases, such as Vibrio-associated infections (Baker-Austin et al., 2016). These infections are caused by Gram-negative bacteria, including Vibrio vulnificus, V. parahaemolyticus, and V. cholerae, which thrive in warm, low-salinity waters, and their prevalence in the natural environment is closely tied to ambient environmental temperatures (Austin, 2005).
根据莫拉等人的说法。 (2022) ,气候危害加剧了影响全球人口的 58%(375 种中的 218 种)传染病。例如,热浪与水上娱乐活动的增加以及弧菌相关感染等几种水传播疾病的相应增加有关Baker-Austin 等,2016 )。这些感染是由革兰氏阴性菌引起的,包括创伤弧菌副溶血弧菌霍乱弧菌,它们在温暖、低盐度的水中繁殖,它们在自然环境中的流行与周围环境温度密切相关(奥斯汀, 2005 )。
Storms, floods, and sea level rise are some of the climatic hazards that have resulted in human displacement, and this has been linked to several diseases. For instance, cases of salmonellosis, leptospirosis, and skin diseases have been reported as a result of human displacement caused by these hazards (Mishra et al., 2019; Alderman et al., 2012). Climate change-induced alterations to microbial communities can also impact the prevalence of antibiotic-resistant bacteria, which pose a significant threat to human health and are an emerging global health concern (WHO, 2014). The impacts of these diseases on human health are a significant concern, and there is a need to identify effective strategies for mitigating these risks.
风暴、洪水和海平面上升是导致人类流离失所的一些气候灾害,这与多种疾病有关。例如,据报道,这些危害导致人类流离失所,导致沙门氏菌病、钩端螺旋体病和皮肤病病例( Mishra 等人,2019 年Alderman 等人,2012