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Development Trends, Current Hotspots, and Research Frontiers of Oyster Reefs: A Bibliometric Analysis Based on CiteSpace

Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou 310012, China
Key Laboratory of Ocean Space Resource Management Technology, Ministry of Natural Resources, Hangzhou 310012, China
Key Laboratory of Songliao Aquatic Environment, Ministry of Education, College of Municipal and Environmental Engineering, Jilin Jianzhu University, Changchun 130118, China
The Nature Conservancy Beijing Representative Office, Beijing 100600, China
Authors to whom correspondence should be addressed.
Water 2023, 15(20), 3619;
Submission received: 26 March 2023 / Revised: 31 May 2023 / Accepted: 22 June 2023 / Published: 16 October 2023
(This article belongs to the Topic Conservation and Management of Marine Ecosystems)


The ocean is the largest reservoir on Earth. With the scarcity of water resources, the destruction of the benign cycle of the marine ecosystem would seriously impact people’s quality of life and health. Oyster reefs, the world’s most endangered marine ecosystems, have been recognized as a global issue due to their numerous essential ecological functions and provision of various ecosystem services. As a result, interest in oyster reef research has been steadily increasing worldwide in recent decades. The goal of this study is to assess the knowledge structure, development trends, research hotspots, and frontier predictions of the global oyster reef research field. Based on 1051 articles selected from the Web of Science Core Collection from 1981 to 2022, this paper conducted a visual analysis of oyster reef ecosystems conservation, restoration, and management. Specifically, it examined research output characteristics, research cooperation networks, highly cited papers and core journals, and keywords. Results indicate a steady rise in research interest in oyster reefs over the past 40 years, with notable acceleration after 2014. Authoritative experts and high-impact organizations were also identified. This paper outlines habitat conservation and restoration, ecosystem services, and the impacts of climate change as the primary research hotspots and frontiers. This paper provides valuable guidance for scholars and regulators concerned about oyster reef conservation to conduct research on oyster reefs.

1. Introduction

Global climate change has a great impact on water resources. Strengthening the protection of water resources and the restoration of water ecological environment are the only ways to realize the harmonious development of man and nature. The ocean is the largest reservoir on Earth. The destruction of the marine ecosystems will seriously affect the quality of life and health of people. The whole ocean is a large ecosystem, including many different levels of marine ecosystems. Further, oyster reefs are among the most depleted marine ecosystems globally. According to Beck et al. [1], an estimated 85% of all oyster reefs globally have been lost. For example, the population size of the eastern oyster (Crassostrea virginica; a.k.a., American oyster) has declined in many estuaries throughout the mid-Atlantic and southeastern United States, including eastern North Carolina and the Chesapeake Bay, where populations have been reduced to 1–2% of their historic peaks approximately a century ago [2]. Historically, it took the Chesapeake Bay’s large oyster population approximately 3.3 days to filter the entire bay’s water, compared with nearly a year for existing populations after the 1980s [2].
Oyster reefs are reefs formed of layers of oysters attaching to one another and can represent massive aggregations. They are widely distributed in estuaries, bays, and lagoons in subtropical and temperate regions. Globally, oyster reefs are found in the European Union (e.g., the Wadden Sea), the USA (e.g., Chesapeake Bay), China (e.g., Bohai Bay), Australia (e.g., Port Phillip Bay), New Zealand (e.g., North Canterbury), Argentina (e.g., Golfo San Matías), Canada (e.g., Nootka Sound) and other places [3]. Oyster reefs are an essential type of marine habitat that provides a wide variety of ecosystem services, such as providing food, improving water clarity [4], facilitating denitrification [5], protecting shorelines [6], increasing landscape diversity [7,8], and providing habitats for marine life [9,10,11]. Therefore, because of their large impacts and ability to transform ecosystems, oysters are known as “ecosystem engineers” [12].
The severe degradation and loss of natural oyster reefs, caused by activities such as overharvesting, disease, habitat degradation [13], water pollution and coastal zone development, has been recognized as a global problem since scientists became aware of their important ecological function [1,14]. Due to the diversity and high values of ecosystem goods and services provided by oyster reefs, there has been increasing interest in oyster reef restoration in many regions of the world [15,16,17]. Early attention to oyster reef recovery was mainly in the USA, especially in the Gulf of Mexico and the East Coast. The species preferred for restoration in the USA has been C. virginica [18]. In addition to the USA, New Zealand, Australia, some European countries, and China have also researched and applied oyster reef restoration practices [3]. To provide ideas and basic information for the whole process of reef restoration project, Fitzsimons et al. [12] published shellfish reef restoration guidelines based on the latest global scientific research achievements and practical experience.
In recent years, people have begun to study the essential ecosystem services provided by oyster reefs [19,20]. Through assessing oyster reef ecosystem services can assist coastal managers in realigning management plans to maximize the benefits of oyster reef restoration efforts. In addition to the research on oyster reef restoration and ecosystem services, extensive work has been conducted on the effectiveness of oyster reefs in serving as coastal defense [21], the impact of global climate change on oyster reefs [22,23,24], the role of oyster reefs in coping with climate change [25,26] and other aspects. Oyster reef studies have also evolved from single-factor exploration to ecological function restoration, from restoring degraded habitats to focusing on habitat changes under the combined influence of climate change and human activities.
At present, there are a number of summaries and literature reviews of oyster reef research [27,28,29,30,31]. As examples of reviews in the field, each of these review articles has its specific emphasis, and each plays an important role in the in-depth exploration of specific research directions. However, a broad-scale understanding of the current research status, hotspots, and future development direction of oyster reefs is lacking. Therefore, it is necessary to carry out a systematic analysis that considers oyster reef research in general based on existing publications. In the face of the large quantity of studies related to oyster reefs, a sufficiently comprehensive and accurate analysis of this field can only be achieved through bibliometrics and a visual review combining quantitative and qualitative methods.
Bibliometrics is an objective and quantitative method of researching and analyzing data obtained from databases [32,33,34,35,36]. CiteSpace is an information visualization software that can be used to scientifically analyze literature and extract pertinent information [37]. According to the characteristics of literature data, this software can conduct analyses of citation networks, co-occurrence networks, and conduct literature coupling [38]. These analyses can show the evolution of hot topics, identify the impacts of landmark studies, and analyze the relationships among articles and references [39]. To date, CiteSpace has been used in many research fields, including microplastics [40,41], biochar [42,43], pesticides [44], sustainable urbanization [45], waste management [46], and others [47,48,49]. Based on the bibliometrics method, this paper applies the CiteSpace software to comprehensively sort the relevant literature on oyster reefs available in the core collection database of the Web of Science. This effort will clearly and intuitively present an overview of oyster reefs research and identify research hotspots and describe the evolution of related topics, as well as identify future trends in this field. This information will provide a useful reference and invaluable insight for future oyster reefs research and conservation practices.

2. Methodology

2.1. Data Sources

The data were obtained from the Web of Science (WoS) Core Collection database.
Using “oyster reef*” or “oyster beds*” as search terms, a total of 1176 documents published between 1981 and 2022 were retrieved. These included various types of documents, such as articles, conference proceedings, review papers, conference abstracts, book chapters, news, briefings, etc., that have been published on oyster reefs. Among the bibliographic documents gathered, research articles made up the highest proportion. Therefore, the literature type ‘‘journal article” was selected to ensure the data source was high quality. Finally, 1051 articles were selected after the removal of duplicates. The documents were imported into the “marked list” of WoS. The selected studies were downloaded in plain text format with “full record and references included” and submitted to CiteSpace for bibliometric analysis.

2.2. Data Analysis

The CiteSpace software (6.1.R2) was used, which is a graphic tool based on the JAVA platform developed by Chaomei Chen of Drexel University, Philadelphia, PA, USA [37]. The scientometric variables considered in this study were: (1) trends in the number of published articles, (2) contributing countries, (3) institutions, (4) authors, (5) distribution and citation track of papers in various disciplines, (6) cited journals, (7) co-citation analysis of references, and (8) research hotspots and trends: through keywords co-occurrence analysis, keywords timeline analysis and burst keywords analysis.
Among them, co-citation analysis examines the citation relationships among publications to identify key publications (or core literature) that have significantly impacted the field of research [50]. The keyword analysis summarizes the most highly emphasized aspects of a study. The analysis of word frequency and the co-occurrence of keywords can objectively and accurately reflect research hotspots in specific fields [46]. The time-axis view of keyword changes can better reflect the distribution and evolution trend of hot topics in the research literature from the time dimension [51]. Combined with the burst words, to grasp the frontiers and trends of oyster reef research field.

3. Results

3.1. Distribution of Publications over the Years

With the 1051 selected publications, looking at the number of articles published each year during the studied period can provide an overview of the progress made in the field of oyster reef research. As illustrated in Figure 1, in the past 40 years, the number of articles published per year increased from 1 to 102 from 1981 in 2020. Generally, this field exhibited slow growth until the mid-1990s. And in the most recent decade, research related to oyster reefs has accelerated rapidly.

3.2. Analysis of Output Characteristics of Articles

3.2.1. Contributing Countries Analysis

The countries contributing the most scientific articles in this field were the USA (with 712 publications, 67.7% of the total) (Figure 2 and Table 1). And the USA was the earliest contributor to conduct oyster reef research (since 1981). Australia and the Netherlands were the second and third largest producers of research in this field, but they contributed significantly less than the USA with 85 and 52 publications, respectively. The next largest contributing countries to oyster reef publications were China (39) and England (36).
The nodes with purple outer rings in Figure 2 exhibit high betweenness centrality. Betweenness centrality is an indicator that reflects the size of the bridge role of a node in the network. When its centrality is greater than 0.1, it plays an important role in this field. From the perspective of the centrality in Table 1, the USA exhibits the strongest centrality (0.52), followed by England (0.26) and Australia (0.23).

3.2.2. Institution Analysis

Network maps can help to identify influential institutions and establish connections among potential collaborators [40,52]. The institutions and cooperative relationships between them are shown in Figure 3. The nodes in Figure 3 represent individual research institutions. The larger the node, the greater the number of articles published by that institution, indicating a stronger academic influence on oyster reef research. The links between nodes reflect the cooperative relationships between research institutions. The more connections there are, the stronger the partnership between institutions.
The Virginia Institute of Marine Science (VIMS) ranked first, with 67 related publications, accounting for 6.4% of all analyzed publications. The University of North Carolina at Chapel Hill was second (65 papers, 6.2%), followed by Northeastern University (40 papers, 3.8%). The next seven institutions were Louisiana State University, Dauphin Island Sea Lab, University of Florida, University of South Alabama, University of Central Florida, TNC, and North Carolina State University. The top 19 institutions in oyster reef research were all based in the USA. The 20th ranked institution was James Cook University, in Australia. This was consistent with the contributing countries analysis, which showed that the USA contributed more than half of all the articles.
Moreover, close collaborative relationships between these institutions were identified. VIMS and TNC each had close ties with 59 institutions, ranking them first in collaborations, followed by National Oceanic and Atmospheric Administration (NOAA) (58 institutions), University of North Carolina at Chapel Hill (55 institutions), and Dauphin Island Sea Lab (53 institutions).
Among all the institutions, only VIMS and TNC had betweenness centrality values exceeding 0.1 (purple outer ring, Figure 3), which indicated that they have played a significant bridging role amongst the collaborating entities producing oyster reef research. VIMS had a large literature quantity and a betweenness centrality of 0.14. VIMS, which is part of the College of William and Mary, has been a prominent institute in oceanography since its founding in 1940. It is considered among the oldest and largest oceanography schools in the USA. Furthermore, VIMS was also among the pioneering organizations in researching oyster reefs. In fact, the institute published its first article on oyster reefs in 1985.
TNC also had a relatively high centrality (0.12) in the network. TNC is among the world’s largest nonprofit environmental organizations, founded in the USA in 1951. Like VIMS, the global headquarters of the TNC is located in Virginia. In addition to research articles, TNC has pioneered and conducted many works on oyster reef conservation and restoration, and on top of publishing the aforementioned Shellfish Reefs at Risk [53], Oyster Habitat Restoration Monitoring and Assessment Handbook [54], and Setting Objectives for Oyster Habitat Restoration Using Ecosystem Services: A Manager’s Guide [55], they released the Restoration Guidelines for Shellfish Reefs in 2019 [12] and Research Report on Conservation and Restoration of Oyster Reef Habitats in China in 2022 [3], among others. In addition, TNC has contributed to relevant conservation and restoration activities in various countries, notably by leading or collaborating in more than 200 oyster reefs and other shellfish reef restoration projects worldwide [3], including in the USA, China, Australia, New Zealand, and Germany.

3.2.3. Author Analysis

Author analysis reveals the scientific publications contributed by individual researchers to this subject [47], as represented by nodes in Figure 4. In this figure, links indicate collaborations between authors.
Table 2 lists the top ten contributing authors by the number of papers the author has published on oyster reefs, including detailed information and the countries they based in. Similar to institutional analysis, the top 10 publishing authors were from the USA. Among them, Jonathan H. Grabowski from Northeastern University, was the author with the most publications on oyster reefs.

3.2.4. Category and Disciplines

Figure 5 shows that oyster reef research has spanned several research disciplines, using a dual-map overlay designed by Chen and Leydesdorff [56]. The clusters of journals in different disciplines are shown using different colors. Depending on the global map of scientific research, the overall visualization of the dual-map overlay can reveal trends in the relevant scientific body of literature [41]. The colored curves in the graph represent reference paths, which clearly show the interdisciplinary relationships [57] within oyster reef research, with the citing journals map on the left and the cited journals map on the right. The stronger the connection, the thicker the line. Two dominant citation lines were present in the interdisciplinary relationships within oyster reef research, as shown by the two blue curves in Figure 5. Clearly, the citing journals were mainly distributed in disciplines labeled “Ecology, Earth, and Marine”; and the cited journals were mainly distributed in disciplines labeled “Earth, Geology, and Geophysics” and “Plant, Ecology, and Zoology”. On the left side of Figure 5, the longer the horizontal axes of the ellipses, the more papers have been published in the corresponding journal. Through this analysis, this study showed that the literature on oyster reefs has been mainly published in journals in the marine biology, marine ecology, and earth fields.

3.2.5. Core Journals Analysis

The top 10 journals with the most published oyster reef research articles, which accounted for 38.9% of the total, are shown in Table 3. Among them, “Journal of Shellfish Research” had the most publications related to oyster reefs (92 articles), accounting for 8.7% of the total. It was followed closely by “Marine Ecology Progress Series” and “Estuaries and Coasts” with 77 and 55 articles, respectively, accounting for 7.3% and 5.2%. “Journal of Shellfish Research”, “Marine Ecology Progress Series” and “Estuaries and Coasts” are authoritative journals in the field of marine and freshwater biology, covering all aspects of marine ecology from fundamental ecological research to applications of ecological principles. Of all the 113 current marine and freshwater biology journals, these three rank 88th, 34th and 28th, respectively. Of the other top 10 journals, “Frontiers in Marine Science” was located in Q1 of the WoS-JCR partition (Q1 was the top 25% of the journals with the highest impact factor), and the other six journals were located in Q2 of the WoS-JCR partition. Based on the analysis above, it is evident that apart from the “Journal of Shellfish Research”, the other nine journals are located in either Q1 or Q2 of the WoS-JCR partition, indicating their high influence within academia.

3.2.6. Most-Cited Journals Analysis

Variables regarding the number of citations linked to publications from each journal are shown in Figure 6 and Table 4. Regarding the citation count analysis, the journals “Marine Ecology Progress Series”, “Journal of Experimental Marine Biology and Ecology”, and “Journal of Shellfish Research” had frequencies of 788, 597, and 574, respectively. The next most-cited journals in oyster reef research were “Science”, “Estuaries”, “Ecology”, “Estuarine Coastal and Shelf Science”, “Marine Biology”, “Bioscience”, and “Estuarine Coastal”. The journals with the highest centrality were “BioScience” (centrality = 0.14) and “Ecology” (centrality = 0.11). A cross-comparison with the co-cited literature analysis below revealed that the relative importance of BioScience was partially because two highly influential articles were published in this journal: “Oyster reefs at risk and recommendations for conservation, restoration, and management” [1] and “Economic valuation of ecosystem services provided by oyster reefs” [58].

3.3. Co-Cited Analysis of References

The articles “Loss, status and trends for coastal marine habitats of Europe” (citations 750) [59], “Oyster reefs at risk and recommendations for conservation, restoration, and management” (citations 738) [1], and “How habitat degradation through fishery disturbance enhances impacts of hypoxia on oyster reefs” (citations 324) [60] were the top most cited articles. Table 5 presents a detailed analysis of the top 10 most cited publications from the WoS analysis. Notably, at the time of analysis, all articles listed in Table 5 had been cited more than 270 times. Michael W. Beck, Charles H. Peterson, and Jonathan H. Grabowski each authored three of the top 10 most cited articles. Among them, the article by Laura Airoldi and Michael W. Beck [59], which had been cited the most, mainly summarized the distribution and status of oyster reefs, historical losses and causes, trends and threats, and protection measures in Europe.

3.4. Keywords Co-Occurrence Analysis

Figure 7 and Table 6 show the co-occurrence of the collected keywords from the publications. In Figure 7, the node size represents the occurrence frequency of keywords, with larger nodes indicating higher frequencies. The analysis showed that keywords including “eastern oyster (Crassostrea virginica)”, and “Chesapeake Bay” were the most frequently occurring of the keywords selected to represent the documents published on oyster reefs. This was followed by the keywords “restoration” and “habitat”, which indicated a secondary focal topics of studies in this field. The only other keyword with a frequency exceeding 100 was “ecosystem service”.
According to Figure 7 and Table 6, the keywords with frequent occurrence represent the research hotspots direction, specifically these are “habitat restoration” and “ecosystem services” of oyster reef. The research hotspot areas were mainly concentrated in the USA (Chesapeake Bay and the Gulf of Mexico). This was consistent with the previous analysis of contributing countries, in which the USA contributed more than half of all the examined articles.

3.5. Keywords Timeline Analysis

Figure 8 depicts the evolution of oyster reef studies in the temporal dimension, showing the changes in keywords throughout the timeline. The larger the node, the higher the frequency is. Nodes marked by purple circles have greater centrality (≥0.1). A link indicates that the keyword is related. The right side of the figure summarizes several important research clusters, named the Wadden Sea, Crassostrea virginica, ecosystem services and Crassostrea gigas, etc.

3.6. Burst Keywords Analysis

With the help of the citation burst function, we can find important keywords, that is, nodes where the number of keyword references suddenly rises or falls. In Figure 9, nodes with burst characteristics are filled in red, and the lengths of the red breakpoints reflect the duration, represented by “begin” and “end” [52]. The burst intensity is represented by the “strength” value. Large changes in the frequencies of keywords are identified as large bursts, which may indicate the novel frontiers in the field at different times. As shown in Figure 9, the top 10 keywords with the highest burst values were “restoration”, “ecosystem service”, “conservation”, “climate change”, “eastern oyster”, “Chesapeake Bay”, “habitat”, “Gulf of Mexico”, and “impact”. Among them, “impact” was used mainly in regard to the impacts of important environmental factors, human activities, and invasive species on oyster reef communities or habitats, as well as the impacts of climate change on oyster species and the role of oyster reefs in responding to global climate change. From the overall distribution of these burst keywords in the relevant research on oyster reefs, it appeared that habitat conservation and restoration, ecosystem services, and the impact of climate change have attracted widespread attention and become priority research frontiers. Hot study areas were mainly focused around Chesapeake Bay and the Gulf of Mexico.

4. Discussion

4.1. Trends in the Number of Published Papers

Overall, the number of publications each year on oyster reefs exhibited an increasing trend, with especially large increases in recent years (Figure 1). This trend may be attributed to the relatively recent global consensus that oyster reef conservation and research will benefit ecosystems and economies worldwide. For example, the world’s largest oyster reef restoration project in Chesapeake Bay started in the 1990s, contributing to the increase in relevant research in the coinciding period. Entering the 21st century, Shellfish Reefs at Risk, the first global review of the condition of oyster reefs was published [1,53], which was followed by shellfish reefs being added to the list of protected Wetlands at the Ramsar Convention on Wetlands in 2012 [12] and the publication of the Oyster Habitat Restoration Monitoring and Assessment Handbook [54] and Setting Objectives for Oyster Habitat Restoration Using Ecosystem Services: A Manager’s Guide [55] by The Nature Conservancy (TNC) in 2014 and 2016, respectively. Oyster restoration in Europe, in contrast, is a new but fast-growing field. In order to best advance the practice of oyster restoration in Europe, the Native Oyster Restoration Alliance (NORA) was established in 2017. The NORA is a growing network of professionals seeking to exchange knowledge on the restoration of native oysters and native oyster habitats in European waters [61]. To date, there has been a much heavier emphasis in the scientific literature around oyster reef conservation and restoration worldwide.

4.2. Scientific Contributions

The most cited article by Laura Airoldi and Michael W. Beck [59], pointed out that oyster reefs may be among the most endangered marine habitats in Europe, with some of the largest impacts on oyster reefs coming from destructive fishing and overexploitation, with additional impacts from disease. Native oyster reefs were ecologically extinct by the 1950s along most European coastlines and well before that in many bays. Their article noted that the sustainable management of the few remaining fragments of native and semi-native coastal habitats in Europe should be prioritized. But perhaps the most cited fact about this article has to do with its broad scope. The article provides an overview of the distributions, historical losses, threats, and conservation measures of coastal habitats in the European gulf as well as estuarine and near-shore continental shelf environments. Furthermore, it covers a variety of coastal habitats in Europe, including coastal wetlands and salt marshes, oyster reefs, seagrass meadows, macroalgal beds, maerl beds, and sedimentary habitats (mudflats, sandflats, and subtidal soft bottoms).
The paper published by Beck et al. (2011) [1] was contributed to by experts from more than ten organizations in the USA, Italy, Uruguay, Australia, and China. They examined the condition of oyster reefs across 144 bays and 44 ecoregions. Overall, the study estimated that 85% of global oyster reefs had been lost. The authors also identified the most promising cost-effective solutions for oyster reef restoration. This article was the first global assessment of oyster reef survival, bringing global attention to this important coastal habitat. After publication, in 2012, shellfish reefs were added to the list of protected wetlands by the Ramsar Convention on Wetlands [12].
To explain the losses of oyster reefs, Lenihan et al. [60] did a series of surveys in the Neuse River estuary, North Carolina, USA. Their findings indicated that interaction between the degradation of reef habitats (height reductions) due to fishery disturbances and extended bottom-water hypoxic/anoxic conditions caused the observed mortality on natural oyster reefs. Interactions among environmental disturbances illustrate the need to use integrative approaches in ecosystem management to restore and sustain estuarine habitats.
The other highly cited articles mainly focus on the cost and feasibility of coastal restoration, the economic valuation of ecosystem services, the role of ecosystems in coastal protection, etc. These widely cited studies have played an important role in promoting the development of oyster reef research and conservation practices.

4.3. Research Hotspots in Oyster Reef

The research hotspots in the oyster reef field focus on oyster reef habitat conservation and restoration, oyster growth, causes of habitat degradation, and oyster reef ecosystem services.
Crassostrea virginica, the most common keyword, is a reef-building oyster species that has formed extensive intertidal oyster reefs in most estuaries and bays on the east coast of North America, from the mid-Atlantic states of the USA to the Gulf of Mexico and the Caribbean [61,62,63]. The next most common keyword was “Chesapeake Bay”, which is a bay located in the middle of the east coast of the USA and is the largest bay in the USA. Historically, this bay has large populations of various oyster species, with C. virginica being most iconic.
The first regions in the world to initiate oyster reef restoration projects and related academic research were in the USA. These included locations across the U.S. Atlantic and Gulf coasts, especially in Chesapeake Bay [64,65,66] and the Gulf Coast [67,68,69]. From 1964 to 2018, 1,768 projects have been implemented, and since 2000, an average of 190 hectares of oyster reefs have been established each year in the USA [18]. Of the species used in restoration projects, C. virginica has predominated. In these projects, a variety of substrates have been used, including oyster shells, mixed oyster substrates, concrete and mixed concrete substrates, and others (e.g., limestone, granite, and surf clam shell) [70,71]. Through the implementation of many projects (generally large-scale with an average project size of 2.85 ha between 1999 and 2016) [18], practitioners have steadily increased the constructed reef area in Chesapeake Bay. As the number of oyster reef restoration projects has gradually increased, scholars have also begun to quantify important ecosystem services provided by oyster reefs in marine ecosystems, such as enhancing reef-generated shoreline stabilization, habitat provisioning, water-quality improvement services, etc. [68,71,72,73].
Currently, oyster reef ecological restoration has been carried out in coastal areas of the USA, Australia, some European countries, New Zealand, and China. For example, in 2020, China issued the Technical guideline for investigation and assessment of coastal ecosystem—Part 7: Oyster reef and the Technical guideline on coastal ecological rehabilitation for hazard mitigation—Part 6: Oyster reef, to provide technical support and a basis for the conservation and restoration of oyster reefs. Oyster reef restoration has become a hotspot in international marine ecological restoration research.

4.4. Hotspots Evolution and Research Frontiers in Oyster Reef

The first identified keyword was “nitrogen”, which appeared in 1990 (Figure 9). Because in coastal ecosystems, nitrogen has been found to be the predominant limiting factor for primary producers. Nitrogen plays an important role in determining ecosystem function. Piehler et al. [74] found significantly higher rates of denitrification in structured habitats such as oyster reefs. Nitrogen removal by these habitats was found to be an important contributor to estuarine ecosystem function. Around 2000, the global consensus began to shift toward oyster reef conservation and research. Subsequently, “habitat degradation” became a hot topic from 2001 to 2007. In addition, “degradation” exhibited continued use with strong citation bursts from 2011 to 2015. During 2013–2022, a large number of research hotspots in the field of oyster reefs emerged and related studies increased in abundance. Since 2013, oyster reef “restoration” has attracted much attention and become a prominent research topic. This remains true to this day, with “restoration” being the keyword with the largest citation bursts and most abundant research achievements. Furthermore, in addition to Chesapeake Bay and the Gulf of Mexico, Mosquito Lagoon has emerged as a hot research area since 2018. A total of 27 articles were retrieved using “oyster reef*” and “Mosquito Lagoon” as search terms. For example, Locher et al. [75] studied the immediate (first-year) effects of restoration on sediment nutrients through a Crassostrea virginica restoration program conducted in Mosquito Lagoon, and Troast et al. [76] explored how fish communities responded in the first 12–24 mo following oyster reef restoration in Mosquito Lagoon. The focus species have been the eastern oyster (Crassostrea virginica) and Pacific oyster (Crassostrea gigas). In addition to the USA, in recent years, other countries have gradually conducted more research on oyster reefs, including Australia (mainly involving the Sydney rock oyster, Saccostrea glomerata), China (mainly in Bohai Bay), and some European countries (e.g., England, Germany, Netherlands, France, and Scotland; mainly involving the Wadden Sea). Along with restoration efforts, the attention paid to the ecosystem services provided by oyster reefs has increased since 2014, indeed “ecosystem service” became the keyword with second strongest burst intensity. Since 2016, under the influence of human activities and global climate change, oyster reef research has tended to diversify. In addition to research on oyster reef restoration and ecosystem services, the impact of global climate change on oyster reefs has become an important research hot topic [22,23,24], as has the role of oyster reefs in responding to global climate change [25,26]. Finally, “substrate” became a hot topic from 2018 to 2022. These keyword bursts illustrate how oyster reef conservation research has shifted through the years.
Looking at evolution of trends over time, it can be seen that oyster reef research has developed from single factor explorations to ecological function restoration, and from the restoration of habitats degraded by human activities to focusing on habitat restoration and development under the joint influences of climate change and human activities. As research has continually provided new insight into the ecological and economic importance of oyster reefs, recent research has increasingly focused on oyster reef conservation, restoration, and ecosystem services.
However, the research evaluating the effectiveness of oyster reef ecological restoration as a Nature-based Solution (NbS), including assessing oyster reef ecosystem services, the impacts of climate change on oyster reefs, the role of oyster reefs in responding to climate change, the effectiveness of oyster reefs as a coastal defense, and effective restoration plans, has not sufficiently matured. Additional and longer-term studies are needed on these topics in the future. For example, oyster reef ecosystem restoration, as a form of NbS, is seen as an increasingly important intervention strategy to counteract the degradation of coastal ecosystems and assist in climate change adaptation. Hynes et al. [77] pointed out that even if oyster reef restoration plans only consider the recreational use value and coastal protection services, without considering the value of many other additional ecosystem services, the benefit-cost ratios of oyster reef protection options always exceed one. But such approaches often face a variety of obstacles that can impede their development, such as the lack of knowledge at the local planner level [78]. However, Narayan et al. [21] also noted the lack of available evidence of wave attenuation by oyster reefs in their literature review focusing on the effectiveness of nature-based coastal defenses. Therefore, additional studies measuring the effectiveness of oyster reefs as a coastal defense are needed to provide a foundation on which to base project goals and set reasonable expectations.
While oyster reef restoration has had considerable success, many challenges remain. For example, restoration costs per unit area are high, the incidence of restoration failure is high, and the pressure imposed by climate change is increasing. Therefore, effective measures must be found to improve restoration efficiency and the resilience of reef ecosystems. Reeves et al. [28] suggested that identifying positive species interactions and systematically incorporating them into restoration practices could improve restoration success and enhance ecosystem services of restored oyster reefs. To do this, further research would be needed to understand the potential impacts of positive interactions and their applicability. Furthermore, Seavey et al. [79] pointed out that understanding the resilience of oyster reef communities to disturbances is key to developing effective conservation and restoration plans. Jiang et al. [17] showed that August was the most favorable window for capturing oyster spat via substratum additions to waters around natural reefs. Hernández et al. [18] pointed out that site characteristics, including access to adequate larval supply and elevation, greatly influence restoration success. Consequently, establishing longer-term, larger-scale, and standardized water-quality and oyster recruitment monitoring datasets to identify sites where restoration activities are likely to stimulate the recovery of self-sustaining, productive oyster reefs is an essential first step when designing projects that will yield positive return-on-investments. Moreover, in order to effectively enhance oyster reef protection and restoration, we must strengthen the academic knowledge in this field and transform practical experience into systematic and scientific guidelines. Furthermore, as pointed out by Draper et al. [80], global temperatures will continue to rise and warming will likely have a stronger impact on community dynamics in oyster reefs. Therefore, oyster reef restoration efforts should focus on accounting for climate change factors to maximize sustainability and success [81].

5. Conclusions

To sum up, the bibliometric analysis based on CiteSpace revealed the development trend, current hotspots and research frontiers of oyster reef research. Over the past 40 years, there has been a noticeable increase in publications on oyster reefs, indicating a growing interest in this subject. As an important coastal ecosystem, the oyster reef has many ecological functions such as providing habitats, purifying water, facilitating de-nitrification, and protecting coastlines. But they are also among the most degraded marine ecosystems and worth protection. Through the analysis of the cooperation network among countries, institutions and authors involved in oyster reef research, it can guide the direction of scientific research cooperation and help us select institutions, experts or journals accordingly. The study on the keywords co-occurrence analysis, the keywords timeline analysis and the identification of burst keywords can provide new insights for the hotspots and trends in this field.
At present, the research of oyster reef shows a trend of diversification. Habitat conservation and restoration, oyster reef ecosystem services, impacts of climate change, biodiversity and selection of substrate are the latest frontiers of research in this field. However, at present, studies on issues such as carbon sequestration in oyster reef ecosystems, ecosystem services assessment and valuation, effectiveness assessments of oyster reef ecological restoration as an NbS, measurement of the effectiveness of oyster reefs as coastal defenses, impacts of global climate change on oyster reef habitat and the roles of oyster reefs in coping with climate change have not been in depth, which is worth further attention. In the future, systematic investigation and research on natural oyster reefs can be carried out. Taking oyster reef ecosystem restoration as an NbS will help realize win–win situations, where ecological protection and economic development both benefit from these natural habitats.

Author Contributions

J.C. (Jie Cheng) and D.L. drafted the original manuscript; L.S. and D.W. collected and collated the materials; W.M., M.S., M.Z. and M.L. drew the diagrams of the paper; J.C. (Jun Cheng) and C.L. revised the entire article; Y.T. designed the whole work. All authors have read and agreed to the published version of the manuscript.


This research was funded by the National Natural Science Foundation of China (grant numbers 41503115, 41706119) and the Fundamental Research Fund of Second Institute of Oceanography (grant numbers JG2110, JG2217).

Institutional Review Board Statement

Not applicable.

Informed Consent Statement

Not applicable.

Data Availability Statement

Not applicable.

Conflicts of Interest

The authors declare no conflict of interest.


  1. Beck, M.W.; Brumbaugh, R.D.; Airoldi, L.; Carranza, A.; Coen, L.D.; Crawford, C.; Defeo, O.; Edgar, G.J.; Hancock, B.; Kay, M.C.; et al. Oyster reefs at risk and recommendations for conservation, restoration, and management. BioScience 2011, 61, 107–116. [Google Scholar] [CrossRef]
  2. Grabowski, J.H.; Peterson, C.H. Restoring oyster reefs to recover ecosystem services. Ecosyst. Eng. 2007, 4, 281–298. [Google Scholar]
  3. The Nature Conservancy. Research Report on Conservation and Restoration of Oyster Reef Habitats in China; The Nature Conservancy: Beijing, China, 2022. (In Chinese) [Google Scholar]
  4. zu Ermgassen, P.S.E.; Spalding, M.D.; Grizzle, R.E.; Brumbaugh, R.D. Quantifying the loss of a marine ecosystem service: Filtration by the eastern oyster in us estuaries. Estuaries Coasts 2013, 36, 36–43. [Google Scholar] [CrossRef]
  5. Newell, R.I.E.; Cornwell, J.C.; Owens, M.S. Influence of simulated bivalve biodeposition and microphytobenthos on sediment nitrogen dynamics: A laboratory study. Limnol. Oceanogr. 2002, 47, 1367–1379. [Google Scholar] [CrossRef]
  6. Piazza, B.P.; Banks, P.D.; La Peyre, M.K. The potential for created oyster shell reefs as a sustainable shoreline protection strategy in louisiana. Restor. Ecol. 2005, 13, 499–506. [Google Scholar] [CrossRef]
  7. Eggleston, D.B. Application of landscape ecological principles to oyster reef habitat restoration. In Oyster Reef Habitat Restoration: A Synopsis and Synthesis of Approaches; Luckenbach, M.W., Mann, R., Wesson, J.A., Eds.; Virginia Institute of Marine Science Press: Gloucester Point, VA, USA, 1999; pp. 213–227. [Google Scholar]
  8. Micheli, F.; Peterson, C.H. Estuarine vegetated habitats as corridors for predator movements. Conserv. Biol. 1999, 13, 869–881. [Google Scholar] [CrossRef]
  9. Peterson, C.H.; Grabowski, J.H.; Powers, S.P. Estimated enhancement of fish production resulting from restoring oyster reef habitat: Quantitative valuation. Mar. Ecol. Prog. Ser. 2003, 264, 249–264. [Google Scholar] [CrossRef]
  10. Ferraro, S.P.; Cole, F.A. Benthic macrofauna-habitat associations in willapa bay, washington, USA. Estuar. Coast. Shelf Sci. 2007, 71, 491–507. [Google Scholar] [CrossRef]
  11. McLeod, I.M.; zu Ermgassen, P.S.E.; Gillies, C.L.; Hancock, B.; Humphries, A. Chapter 25—Can bivalve habitat restoration improve degraded estuaries? In Coasts and Estuaries: The Future; Wolanski, E., Day, J.W., Elliott, M., Ramachandran, R., Eds.; Elsevier: Amsterdam, The Netherlands, 2019; pp. 427–442. [Google Scholar]
  12. Fitzsimons, J.; Branigan, S.; Brumbaugh, R.D.; McDonald, T.; zu Ermgassen, P.S.E. Restoration Guidelines for Shellfish Reefs; The Nature Conservancy: Arlington, VA, USA, 2019. [Google Scholar]
  13. Morgan, L.M.; Rakocinski, C.F. Predominant factors limiting the recovery of the eastern oyster (Crassostrea virginica) in western mississippi sound, USA. Estuar. Coast. Shelf Sci. 2022, 264, 107652. [Google Scholar] [CrossRef]
  14. zu Ermgassen, P.S.E.; Spalding, M.D.; Blake, B.; Coen, L.D.; Dumbauld, B.; Geiger, S.; Grabowski, J.H.; Grizzle, R.; Luckenbach, M.; McGraw, K.; et al. Historical ecology with real numbers: Past and present extent and biomass of an imperilled estuarine habitat. Proc. R. Soc. B-Biol. Sci. 2012, 279, 3393–3400. [Google Scholar] [CrossRef]
  15. Kennedy, V.S.; Breitburg, D.L.; Christman, M.C.; Luckenbach, M.W.; Paynter, K.; Kramer, J.; Sellner, K.G.; Dew-Baxter, J.; Keller, C.; Mann, R. Lessons learned from efforts to restore oyster populations in maryland and virginia, 1990 to 2007. J. Shellfish Res. 2011, 30, 719–731. [Google Scholar] [CrossRef]
  16. Hatchell, B.; Konchar, K.; Merrill, M.; Shea, C.; Smith, K. Use of biodegradable coir for subtidal oyster habitat restoration: Testing two reef designs in northwest florida. Estuaries Coasts 2022, 45, 2675–2689. [Google Scholar] [CrossRef]
  17. Jiang, W.; Shi, W.J.; Li, N.N.; Fan, R.L.; Zhang, W.K.; Quan, W.M. Oyster and barnacle recruitment dynamics on and near a natural reef in china: Implications for oyster reef restoration. Front. Mar. Sci. 2022, 9, 905373. [Google Scholar] [CrossRef]
  18. Hernández, A.B.; Brumbaugh, R.D.; Frederick, P.; Grizzle, R.; Luckenbach, M.W.; Peterson, C.H.; Angelini, C. Restoring the eastern oyster: How much progress has been made in 53 years? Front. Ecol. Environ. 2018, 16, 463–471. [Google Scholar] [CrossRef]
  19. La Peyre, M.K.; Humphries, A.T.; Casas, S.M.; La Peyre, J.F. Temporal variation in development of ecosystem services from oyster reef restoration. Ecol. Eng. 2014, 63, 34–44. [Google Scholar] [CrossRef]
  20. Hogan, S.; Reidenbach, M.A. Quantifying tradeoffs in ecosystem services under various oyster reef restoration designs. Estuaries Coasts 2022, 45, 677–690. [Google Scholar] [CrossRef]
  21. Narayan, S.; Beck, M.W.; Reguero, B.G.; Losada, I.J.; van Wesenbeeck, B.; Pontee, N.; Sanchirico, J.N.; Ingram, J.C.; Lange, G.M.; Burks-Copes, K.A. The effectiveness, costs and coastal protection benefits of natural and nature-based defences. PLoS ONE 2016, 11, e0154735. [Google Scholar] [CrossRef]
  22. Lemasson, A.J.; Knights, A.M. Differential responses in anti-predation traits of the native oyster ostrea edulis and invasive magallana gigas to ocean acidification and warming. Mar. Ecol.-Prog. Ser. 2021, 665, 87–102. [Google Scholar] [CrossRef]
  23. McClenachan, G.; Witt, M.; Walters, L.J. Replacement of oyster reefs by mangroves: Unexpected climate-driven ecosystem shifts. Glob. Chang. Biol. 2021, 27, 1226–1238. [Google Scholar] [CrossRef]
  24. Ridge, J.T.; Rodriguez, A.B.; Fodrie, F.J. Evidence of exceptional oyster-reef resilience to fluctuations in sea level. Ecol. Evol. 2017, 7, 10409–10420. [Google Scholar] [CrossRef]
  25. Fodrie, F.J.; Rodriguez, A.B.; Gittman, R.K.; Grabowski, J.H.; Lindquist, N.L.; Peterson, C.H.; Piehler, M.F.; Ridge, J.T. Oyster reefs as carbon sources and sinks. Proc. R. Soc. B-Biol. Sci. 2017, 284, 20170891. [Google Scholar] [CrossRef]
  26. Ridge, J.T.; Rodriguez, A.B.; Fodrie, F.J. Salt marsh and fringing oyster reef transgression in a shallow temperate estuary: Implications for restoration, conservation and blue carbon. Estuaries Coasts 2017, 40, 1013–1027. [Google Scholar] [CrossRef]
  27. Goelz, T.; Vogt, B.; Hartley, T. Alternative substrates used for oyster reef restoration: A review. J. Shellfish Res. 2020, 39, 1–12. [Google Scholar] [CrossRef]
  28. Reeves, S.E.; Renzi, J.J.; Fobert, E.K.; Silliman, B.R.; Hancock, B.; Gillies, C.L. Facilitating better outcomes: How positive species interactions can improve oyster reef restoration. Front. Mar. Sci. 2020, 7, 656. [Google Scholar] [CrossRef]
  29. Howie, A.H.; Bishop, M.J. Contemporary oyster reef restoration: Responding to a changing world. Front. Ecol. Evol. 2021, 9, 689915. [Google Scholar] [CrossRef]
  30. McAfee, D.; McLeod, I.M.; Boström-Einarsson, L.; Gillies, C.L. The value and opportunity of restoring Australia’s lost rock oyster reefs. Restor. Ecol. 2020, 28, 304–314. [Google Scholar] [CrossRef]
  31. Brumbaugh, R.D.; Coen, L.D. Contemporary approaches for small-scale oyster reef restoration to address substrate versus recruitment limitation: A review and comments relevant for the Olympia oyster, Ostrea lurida Carpenter 1864. J. Shellfish Res. 2009, 28, 147–161. [Google Scholar] [CrossRef]
  32. You, J.; Chen, X.; Chen, L.; Chen, J.; Chai, B.; Kang, A.; Lei, X.; Wang, S. A Systematic Bibliometric Review of Low Impact Development Research Articles. Water 2022, 14, 2675. [Google Scholar] [CrossRef]
  33. Chen, L.; Li, W.; Li, J.; Fu, Q.; Wang, T. Evolution trend research of global ocean power generation based on a 45-year scientometric analysis. J. Mar. Sci. Eng. 2021, 9, 218. [Google Scholar] [CrossRef]
  34. Lai, Q.; Ma, J.; He, F.; Zhang, A.; Pei, D.; Wei, G.; Zhu, X. Research Development, Current Hotspots, and Future Directions of Blue Carbon: A Bibliometric Analysis. Water 2022, 14, 1193. [Google Scholar] [CrossRef]
  35. Jović, M.; Tijan, E.; Brčić, D.; Pucihar, A. Digitalization in maritime transport and seaports: Bibliometric, content and thematic analysis. J. Mar. Sci. Eng. 2022, 10, 486. [Google Scholar] [CrossRef]
  36. Zhang, Z.; Jin, G.; Hu, Y.; He, N.; Niu, J. Performance Management of Natural Resources: A Systematic Review and Conceptual Framework for China. Water 2022, 14, 3338. [Google Scholar] [CrossRef]
  37. Chen, C.M. Citespace ii: Detecting and visualizing emerging trends and transient patterns in scientific literature. J. Am. Soc. Inf. Sci. Technol. 2006, 57, 359–377. [Google Scholar] [CrossRef]
  38. Najmi, A.; Rashidi, T.H.; Abbasi, A.; Waller, S.T. Reviewing the transport domain: An evolutionary bibliometrics and network analysis. Scientometrics 2017, 110, 843–865. [Google Scholar] [CrossRef]
  39. Lopes, A.; de Carvalho, M.M. Evolution of the open innovation paradigm: Towards a contingent conceptual model. Technol. Forecast. Soc. Chang. 2018, 132, 284–298. [Google Scholar] [CrossRef]
  40. Zhang, Y.; Pu, S.; Lv, X.; Gao, Y.; Ge, L. Global trends and prospects in microplastics research: A bibliometric analysis. J. Hazard. Mater. 2020, 400, 123110. [Google Scholar] [CrossRef]
  41. Yao, L.; Hui, L.; Yang, Z.; Chen, X.; Xiao, A. Freshwater microplastics pollution: Detecting and visualizing emerging trends based on citespace ii. Chemosphere 2020, 245, 125627. [Google Scholar] [CrossRef]
  42. Kamali, M.; Jahaninafard, D.; Mostafaie, A.; Davarazar, M.; Gomes, A.P.D.; Tarelho, L.A.C.; Dewil, R.; Aminabhavi, T.M. Scientometric analysis and scientific trends on biochar application as soil amendment. Chem. Eng. J. 2020, 395, 125128. [Google Scholar] [CrossRef]
  43. Li, M.; Wang, Y.; Shen, Z.; Chi, M.; Lv, C.; Li, C.; Bai, L.; Thabet, H.K.; El-Bahy, S.M.; Ibrahim, M.M.; et al. Investigation on the evolution of hydrothermal biochar. Chemosphere 2022, 307, 135774. [Google Scholar] [CrossRef]
  44. de Castilhos Ghisi, N.; Zuanazzi, N.R.; Fabrin, T.M.C.; Oliveira, E.C. Glyphosate and its toxicology: A scientometric review. Sci. Total Environ. 2020, 733, 139359. [Google Scholar] [CrossRef]
  45. Zhang, D.; Xu, J.; Zhang, Y.; Wang, J.; He, S.; Zhou, X. Study on sustainable urbanization literature based on web of science, scopus, and China national knowledge infrastructure: A scientometric analysis in citespace. J. Clean. Prod. 2020, 264, 121537. [Google Scholar] [CrossRef]
  46. Li, Y.; Li, M.; Sang, P. A bibliometric review of studies on construction and demolition waste management by using citespace. Energy Build. 2022, 258, 111822. [Google Scholar] [CrossRef]
  47. Davarazar, M.; Mostafaie, A.; Jahanianfard, D.; Davarazar, P.; Ghiasi, S.A.B.; Gorchich, M.; Nemati, B.; Kamali, M.; Aminabhavi, T.M. Treatment technologies for pharmaceutical effluents-a scientometric study. J. Environ. Manag. 2020, 254, 109800. [Google Scholar] [CrossRef]
  48. Wang, X.; Zhang, Y.; Zhang, J.; Fu, C.; Zhang, X. Progress in urban metabolism research and hotspot analysis based on citespace analysis. J. Clean. Prod. 2021, 281, 125224. [Google Scholar] [CrossRef]
  49. Fu, L.; Mao, S.; Chen, F.; Zhao, S.; Su, W.; Lai, G.; Yu, A.; Lin, C.T. Graphene-based electrochemical sensors for antibiotic detection in water, food and soil: A scientometric analysis in citespace (2011–2021). Chemosphere 2022, 297, 134127. [Google Scholar] [CrossRef]
  50. Yu, D.J.; Xu, C. Mapping research on carbon emissions trading: A co-citation analysis. Renew. Sustain. Energy Rev. 2017, 74, 1314–1322. [Google Scholar] [CrossRef]
  51. Li, L.; Liu, X.J.; Zhang, X.Y. Uncovering the research progress and hotspots on the public use of recycled water: A bibliometric perspective. Environ. Sci. Pollut. Res. 2021, 28, 44845–44860. [Google Scholar] [CrossRef]
  52. Shi, J.J.; Shi, S.Q.; Shi, S.; Jia, Q.L.; Yuan, G.Z.; Chu, Y.G.; Wang, H.; Hu, Y.H.; Cui, H.M. Bibliometric analysis of potassium channel research. Channels 2020, 14, 18–27. [Google Scholar] [CrossRef]
  53. Beck, M.W.; Brumbaugh, R.D.; Airoldi, L.; Carranza, A.; Coen, L.D.; Crawford, C.; Defeo, O.; Edgar, G.; Hancock, B.; Kay, M.; et al. Shellfish Reefs at Risk: A Global Analysis of Problems and Solutions; The Nature Conservancy: Arlington, VA, USA, 2009; 52p. [Google Scholar]
  54. Baggett, L.P.; Powers, S.P.; Brumbaugh, R.; Coen, L.D.; DeAngelis, B.; Greene, J.; Hancock, B.; Morlock, S. Oyster Habitat Restoration Monitoring and Assessment Handbook; The Nature Conservancy: Arlington, VA, USA, 2014. [Google Scholar]
  55. zu Ermgassen, P.; Hancock, B.; DeAngelis, B.; Greene, J.; Schuster, E.; Spalding, M.; Brumbaugh, R. Setting Objectives for Oyster Habitat Restoration Using Ecosystem Services: A Manager’s Guide; The Nature Conservancy: Arlington, VA, USA, 2016; 76p. [Google Scholar]
  56. Chen, C.; Leydesdorff, L. Patterns of connections and movements in dual-map overlays: A new method of publication portfolio analysis. J. Assoc. Inf. Sci. Technol. 2014, 65, 334–351. [Google Scholar] [CrossRef]
  57. Aryadoust, V.; Ang, B.H. Exploring the frontiers of eye tracking research in language studies: A novel co-citation scientometric review. Comput. Assist. Lang. Learn. 2021, 34, 898–933. [Google Scholar] [CrossRef]
  58. Grabowski, J.H.; Brumbaugh, R.D.; Conrad, R.F.; Keeler, A.G.; Opaluch, J.J.; Peterson, C.H.; Piehler, M.F.; Powers, S.P.; Smyth, A.R. Economic Valuation of Ecosystem Services Provided by Oyster Reefs. BioScience 2012, 62, 900–909. [Google Scholar] [CrossRef]
  59. Airoldi, L.; Beck, M.W. Loss, status and trends for coastal marine habitats of Europe. Oceanogr. Mar. Biol. 2007, 45, 345–405. [Google Scholar]
  60. Lenihan, H.S.; Peterson, C.H. How habitat degradation through fishery disturbance enhances impacts of hypoxia on oyster reefs. Ecol. Appl. 1998, 8, 128–140. [Google Scholar] [CrossRef]
  61. Bahr, L.M.; Lanier, W.P. The Ecology of Intertidal Oyster Reefs of the South Atlantic Coast: A Community Profile; FWS/OBS-81/15; U.S. Fish Wildlife Service, Office of Biological Services: Washington, DC, USA, 1981; 105p.
  62. Dellapenna, T.M. Oyster reef. In Encyclopedia of Estuaries; Kennish, M.J., Ed.; Springer: Dordrecht, The Netherlands, 2016; pp. 470–474. [Google Scholar]
  63. Straquadine, N.R.W.; Kudela, R.M.; Gobler, C.J. Hepatotoxic shellfish poisoning: Accumulation of microcystins in eastern oysters (crassostrea virginica) and asian clams (corbicula fluminea) exposed to wild and cultured populations of the harmful cyanobacteria, microcystis. Harmful Algae 2022, 115, 102236. [Google Scholar] [CrossRef]
  64. Harding, J.M.; Mann, R. Estimates of naked goby (gobiosoma bosc), striped blenny (chasmodes bosquianus) and eastern oyster (Crassostrea virginica) larval production around a restored chesapeake bay oyster reef. Bull. Mar. Sci. 2000, 66, 29–45. [Google Scholar]
  65. Rodney, W.S.; Paynter, K.T. Comparisons of macrofaunal assemblages on restored and non-restored oyster reefs in mesohaline regions of chesapeake bay in maryland. J. Exp. Mar. Biol. Ecol. 2006, 335, 39–51. [Google Scholar] [CrossRef]
  66. Lipcius, R.N.; Burke, R.P. Successful recruitment, survival and long-term persistence of eastern oyster and hooked mussel on a subtidal, artificial restoration reef system in chesapeake bay. PLoS ONE 2018, 13, e0204329. [Google Scholar] [CrossRef]
  67. Plutchak, R.; Major, K.; Cebrian, J.; Foster, C.D.; Miller, M.E.C.; Anton, A.; Sheehan, K.L.; Heck, K.L.; Powers, S.P. Impacts of oyster reef restoration on primary productivity and nutrient dynamics in tidal creeks of the north central gulf of mexico. Estuaries Coasts 2010, 33, 1355–1364. [Google Scholar] [CrossRef]
  68. La Peyre, M.; Furlong, J.; Brown, L.A.; Piazza, B.P.; Brown, K. Oyster reef restoration in the northern gulf of mexico: Extent, methods and outcomes. Ocean Coast. Manag. 2014, 89, 20–28. [Google Scholar] [CrossRef]
  69. Pine, W.E.; Johnson, F.A.; Frederick, P.C.; Coggins, L.G. Adaptive management in practice and the problem of application at multiple scales-insights from oyster reef restoration on florida’s gulf coast. Mar. Coast. Fish. 2022, 14, e10192. [Google Scholar] [CrossRef]
  70. Powers, S.P.; Peterson, C.H.; Grabowski, J.H.; Lenihan, H.S. Success of constructed oyster reefs in no-harvest sanctuaries: Implications for restoration. Mar. Ecol. Prog. Ser. 2009, 389, 159–170. [Google Scholar] [CrossRef]
  71. Brown, L.A.; Furlong, J.N.; Brown, K.M.; La Peyre, M.K. Oyster reef restoration in the northern gulf of mexico: Effect of artificial substrate and age on nekton and benthic macroinvertebrate assemblage use. Restor. Ecol. 2014, 22, 214–222. [Google Scholar] [CrossRef]
  72. Waldbusser, G.G.; Powell, E.N.; Mann, R. Ecosystem effects of shell aggregations and cycling in coastal waters: An example of chesapeake bay oyster reefs. Ecology 2013, 94, 895–903. [Google Scholar] [CrossRef]
  73. Pfirrmann, B.W.; Seitz, R.D. Ecosystem services of restored oyster reefs in a Chesapeake Bay tributary: Abundance and foraging of estuarine fishes. Mar. Ecol. Prog. Ser. 2019, 628, 155–169. [Google Scholar] [CrossRef]
  74. Piehler, M.F.; Smyth, A.R. Habitat-specific distinctions in estuarine denitrification affect both ecosystem function and services. Ecosphere 2011, 2, 12. [Google Scholar] [CrossRef]
  75. Locher, B.; Hurst, N.R.; Walters, L.J.; Chambers, L.G. Juvenile oyster (Crassostrea virginica) biodeposits contribute to a rapid rise in sediment nutrients on restored intertidal oyster reefs (Mosquito Lagoon, FL, USA). Estuaries Coasts 2021, 44, 1363–1379. [Google Scholar] [CrossRef]
  76. Troast, B.V.; Walters, L.J.; Cook, G.S. A multi-tiered assessment of fish community responses to habitat restoration in a coastal lagoon. Mar. Ecol.-Prog. Ser. 2022, 698, 1–14. [Google Scholar] [CrossRef]
  77. Hynes, S.; Burger, R.; Tudella, J.; Norton, D.; Chen, W. Estimating the costs and benefits of protecting a coastal amenity from climate change-related hazards: Nature based solutions via oyster reef restoration versus grey infrastructure. Ecol. Econ. 2022, 194, 107349. [Google Scholar] [CrossRef]
  78. Johns, C.M. Understanding barriers to green infrastructure policy and stormwater management in the city of Toronto: A shift from grey to green or policy layering and conversion? J. Plan. Lit. 2022, 37, 152–153. [Google Scholar] [CrossRef]
  79. Seavey, J.R.; Pine, W.E.; Frederick, P.; Sturmer, L.; Berrigan, M. Decadal changes in oyster reefs in the big bend of Florida’s gulf coast. Ecosphere 2011, 2, 114. [Google Scholar] [CrossRef]
  80. Draper, A.M.; Weissburg, M.J. Differential effects of warming and acidification on chemosensory transmission and detection may strengthen non-consumptive effects of blue crab predators (Callinectes sapidus) on mud crab prey (Panopeus herbstii). Front. Mar. Sci. 2022, 9, 1518. [Google Scholar] [CrossRef]
  81. Pereira, R.R.C.; Scanes, E.; Parker, L.M.; Byrne, M.; Cole, V.J.; Ross, P.M. Restoring the flat oyster Ostrea angasi in the face of a changing climate. Mar. Ecol.-Prog. Ser. 2019, 625, 27–39. [Google Scholar] [CrossRef]
Figure 1. The annual number of published articles on oyster reefs extracted from the WoS Core Collection database.
Figure 1. The annual number of published articles on oyster reefs extracted from the WoS Core Collection database.
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Figure 2. Contributions of various countries worldwide in the production of articles on oyster reefs. The subjects began in 1981, and the evolution until 2022 is shown from left to right.
Figure 2. Contributions of various countries worldwide in the production of articles on oyster reefs. The subjects began in 1981, and the evolution until 2022 is shown from left to right.
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Figure 3. The network map of institutions for oyster reef research.
Figure 3. The network map of institutions for oyster reef research.
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Figure 4. The network map of authors for scientific research on oyster reefs.
Figure 4. The network map of authors for scientific research on oyster reefs.
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Figure 5. Dual-map overlays of oyster reefs research.
Figure 5. Dual-map overlays of oyster reefs research.
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Figure 6. Journal co-citation network.
Figure 6. Journal co-citation network.
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Figure 7. A schematic representation of network analysis of keywords appeared in scientific documents published on oyster reefs.
Figure 7. A schematic representation of network analysis of keywords appeared in scientific documents published on oyster reefs.
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Figure 8. Visualization of keywords timeline analysis.
Figure 8. Visualization of keywords timeline analysis.
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Figure 9. Top 30 keywords with the strongest citation bursts.
Figure 9. Top 30 keywords with the strongest citation bursts.
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Table 1. Top 10 contributing countries in terms of publications on oyster reefs. “Year” represents the time of the first appearance.
Table 1. Top 10 contributing countries in terms of publications on oyster reefs. “Year” represents the time of the first appearance.
RatingCountryYear aCentrality bFrequencyAverage cContribution (%)
4Peoples R China20070.023933.7
Notes: a “Year” represents the time of the first appearance. b Centrality: Betweenness centrality. c Average: The average number of publications per year, Average = Frequency/(2022 − Year) (keep the integers).
Table 2. List of the top 10 contributing authors in terms of publications on oyster reefs including detailed information and their host countries.
Table 2. List of the top 10 contributing authors in terms of publications on oyster reefs including detailed information and their host countries.
RatingAuthorCountryCountYearContribution (%)
1Grabowski, J.H.USA3420003.2
2Walters, L.J.USA2920022.8
3Powers, S.P.USA2420022.3
4Eggleston, D.B.USA2319982.2
5Peterson, C.H.USA2319982.2
6Powell, E.N.USA1919871.8
7La Peyer, M.USA1920051.8
8Piehler, M.F.USA1820111.7
9Mann, R.USA1819981.7
10Harding, J.M.USA1719991.6
Table 3. Top 10 journals in the field of oyster reefs.
Table 3. Top 10 journals in the field of oyster reefs.
RatingCiting JournalCountContribution (%)Impact Factor
1Journal of Shellfish Research928.71.218
2Marine Ecology Progress Series777.32.915
3Estuaries and Coasts555.23.032
4Journal of Experimental Marine Biology and Ecology383.62.476
5PLoS ONE312.93.752
6Restoration Ecology312.94.181
7Frontiers in Marine Science242.35.247
8Estuarine Coastal and Shelf Science232.23.229
9Ecological Engineering191.84.379
10Journal of Sea Research191.82.287
Table 4. Detailed information about the journals that received citations by the published documents collected for the present scientometric study on oyster reefs.
Table 4. Detailed information about the journals that received citations by the published documents collected for the present scientometric study on oyster reefs.
RatingCited JournalCentralityFrequency
1Marine Ecology Progress Series0.02788
2Journal of Experimental Marine Biology and Ecology0.02597
3Journal of Shellfish Research0.05574
7Estuarine Coastal and Shelf Science0.04467
8Marine Biology0.04446
10Estuarine Coastal0.00382
Table 5. Top 10 highly cited papers in the field of oyster reefs according to the WoS Core Collection database.
Table 5. Top 10 highly cited papers in the field of oyster reefs according to the WoS Core Collection database.
1Loss, status and trends for coastal marine habitats of Europe2007Airoldi, L. and Beck, M.W.Oceanography and Marine Biology750 [59]
2Oyster Reefs at Risk and Recommendations for Conservation, Restoration, and Management2011Beck, M.W.; Brumbaugh, R.D.; Airoldi, L.; et al.BioScience738 [1]
3How habitat degradation through fishery disturbance enhances impacts of hypoxia on oyster reefs1998Lenihan, H.S. and Peterson, C.H.Ecological Applications324 [60]
4The cost and feasibility of marine coastal restoration2016Bayraktarov, E.; Saunders, M.I.; Abdullah, S.; et al.Ecological Applications322
5Economic Valuation of Ecosystem Services Provided by Oyster Reefs2012Grabowski, J.H.; Brumbaugh, R.D.; Conrad, R.F.; et al.BioScience320 [58]
6The role of ecosystems in coastal protection: Adapting to climate change and coastal hazards2014Spalding, M.D.; Ruffo, S.; Lacambra, C.; et al.Ocean and Coastal Management290
7Epizootiology of Perkinsus marinus disease of oysters in Chesapeake Bay, with emphasis on data since 19851996Burreson, E.M. and Calvo, L.M.R.Journal of Shellfish Research286
8Habitat complexity disrupts predator-prey interactions but not the trophic cascade on oyster reefs2004Grabowski, J.H.Ecology284
9Estimated enhancement of fish production resulting from restoring oyster reef habitat: quantitative valuation2003Peterson, C.H.; Grabowski, J.H. and Powers, S.P.Marine Ecology Progress Series284 [9]
10Physical-biological coupling on oyster reefs: How habitat structure influences individual performance1999Lenihan, H.S.Ecological Monographs279
Table 6. The output of keywords co-occurring analysis and respective parameters of scientometric analysis. These keywords are most widely used to represent scientific documents published so far on oyster reefs.
Table 6. The output of keywords co-occurring analysis and respective parameters of scientometric analysis. These keywords are most widely used to represent scientific documents published so far on oyster reefs.
1oyster reef0.032931990
2Crassostrea virginica0.092701992
3Chesapeake Bay0.091691990
5eastern oyster0.051151996
7ecosystem service0.051012008
17Crassostrea gigas0.08531992
21Gulf of Mexico0.04451997
23climate change0.07392004
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Cheng, J.; Lu, D.; Sun, L.; Mo, W.; Shen, M.; Li, M.; Li, C.; Zhang, M.; Cheng, J.; Wang, D.; et al. Development Trends, Current Hotspots, and Research Frontiers of Oyster Reefs: A Bibliometric Analysis Based on CiteSpace. Water 2023, 15, 3619.

AMA Style

Cheng J, Lu D, Sun L, Mo W, Shen M, Li M, Li C, Zhang M, Cheng J, Wang D, et al. Development Trends, Current Hotspots, and Research Frontiers of Oyster Reefs: A Bibliometric Analysis Based on CiteSpace. Water. 2023; 15(20):3619.

Chicago/Turabian Style

Cheng, Jie, Duian Lu, Li Sun, Wei Mo, Mengnan Shen, Ming Li, Chenyang Li, Ming Zhang, Jun Cheng, Degang Wang, and et al. 2023. "Development Trends, Current Hotspots, and Research Frontiers of Oyster Reefs: A Bibliometric Analysis Based on CiteSpace" Water 15, no. 20: 3619.

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