The Blue Finance Frontier: Mapping Sustainability, Innovation, and Resilience in Ocean Investment Research

Abstract

Blue Finance has rapidly emerged as a strategic frontier for channeling capital toward sustainable and resilient ocean economies, connecting financial innovation with environmental governance and climate responsibility. However, its conceptual foundations remain fragmented, hindering theoretical integration and policy application. This study conducts a comprehensive bibliometric and science-mapping analysis of 217 Scopus-indexed publications (2007–2025), using Biblioshiny (Bibliometrix v4.2.2), VOSviewer v1.6.20, and Gephi v0.10.1 to trace the intellectual evolution, thematic configuration, and research agenda of Blue Finance. The analysis reveals a rapidly consolidating field that has evolved through three distinct phases, anchored in sustainability science but constrained by limited financial integration. The field’s cognitive structure is organized around three interlinked pillars: the climate–environmental interface, sustainability integration and governance, and innovative financial mechanisms enhancing economic resilience. Emerging research hotspots in blue bonds, sustainable finance, and blue justice signal a paradigm shift from normative ecological awareness to actionable, market-aligned resilience. The findings outline a forward-looking research agenda that strengthens theoretical consolidation, governance accountability, and sustainable investment frameworks. This study offers strategic guidance for researchers, investors, and policymakers, positioning Blue Finance as a transformative catalyst that unites innovation, resilience, and equity in shaping the future of sustainable finance.

1. Introduction

The blue economy has become a central pillar of global sustainable development, bridging economic opportunity with environmental stewardship. Defined as the sustainable use of ocean resources to support economic growth, improve livelihoods, and safeguard marine ecosystem health, particularly in coastal regions [1,2], it holds a pivotal place in international policy agendas. This domain makes critical contributions to food security, renewable energy transitions, maritime transport, and climate regulation. Nevertheless, its expansion unfolds amid accelerating ecological degradation. Intensifying climate change, marine pollution, biodiversity loss, and resource overexploitation place unprecedented pressure on ocean ecosystems [3,4]. Recent advances in marine geology also indicate that submarine landslides impose significant environmental and economic pressures on marine economies [5]. Balancing economic growth with ecological preservation has therefore become a structural imperative for governing ocean-based economies [6].

Blue finance has emerged as a strategic response to this imperative, mobilizing capital to support sustainable ocean-based activities. It encompasses a spectrum of mechanisms, including debt instruments, market-based products, and ecosystem-based tools, that channel financial flows toward marine conservation and sustainable maritime development. By doing so, Blue Finance contributes directly to Sustainable Development Goal 14 (“Life Below Water”) and strengthens the financial architecture underpinning ocean governance [7]. Unlike the broader blue economy, which encompasses all marine-related economic activities, blue finance refers specifically to financial mechanisms and capital flows targeted at sustainable, climate-resilient ocean investments.

Despite its strategic importance, the blue finance landscape remains fragmented, underfunded, and conceptually ambiguous. Investment flows are insufficient to meet the needs of marine conservation and adaptation [8,9]. Intensifying environmental pressures further weaken fragile ecosystems and expose coastal communities to climate risks [10]. Scholarly output has grown rapidly, spanning environmental economics, sustainable finance, and ocean governance. This expansion reflects intellectual vitality but also reveals blurred conceptual boundaries and tensions between ecological objectives and financial imperatives, which complicate the identification of thematic cores and research frontiers. This conceptual fragmentation underscores the need for a rigorous scientific synthesis that consolidates dispersed insights into a coherent, cumulative knowledge structure.

Addressing this conceptual ambiguity requires a structured and critical synthesis of the field. Bibliometric analysis provides a rigorous framework for mapping knowledge structures and thematic patterns. It enables researchers to uncover intellectual foundations and conceptual configurations by combining performance indicators with science-mapping techniques [11]. While the domains of green and climate finance have already benefited from extensive bibliometric studies, blue finance remains insufficiently mapped, limiting the capacity to build cumulative knowledge and to design coherent strategic frameworks for future research and policy. Clarifying the academic significance of blue finance is therefore essential. Only a systematic and conceptually grounded synthesis can organize its fragmented evidence base, trace its intellectual evolution, and provide the coherent foundation needed to advance future research and policy design. This study aims to address this gap by offering an in-depth and structured bibliometric analysis of the blue finance literature, providing a comprehensive overview of its current research landscape and highlighting its main thematic directions and knowledge structures.

This study’s main contributions are threefold. First, it provides a comprehensive bibliometric mapping of blue finance, offering empirical visibility into its intellectual foundations while identifying its most influential authors, affiliations, sources, and seminal references. Second, it elucidates the field’s conceptual architecture by identifying thematic clusters and tracing the evolution of research priorities from ecological awareness to financial innovation and governance integration. Third, it advances a forward-looking research agenda that bridges finance, sustainability, and policy, providing a strategic reference for scholars, investors, and decision-makers seeking to align capital markets with marine sustainability and climate resilience objectives. Collectively, these contributions highlight why it is both timely and academically necessary to consolidate, organize, and critically reflect on the progress of blue finance research.

The remainder of this paper is structured as follows. Section 2 provides the theoretical background. Section 3 details the methodology and data. Section 4 presents the results. Section 5 discusses the findings. Section 6 concludes with key implications.

2. Conceptualization and Theoretical Background

2.1. Conceptual Foundations of the Blue Economy and Blue Finance Within Sustainable Finance

The blue economy refers to the sustainable use of ocean and coastal resources to generate economic value while safeguarding long-term ecosystem health [12]. It has emerged in response to accelerating pressures on marine systems, including climate change, pollution, biodiversity loss, and habitat degradation. It therefore requires integrated perspectives from social sciences, economics, and environmental governance [3,4]. Its core objective is to balance economic development with marine conservation, covering sectors including fisheries, aquaculture, biotechnology, marine tourism, and renewable marine energy, and aligning closely with SDG 14. Conceptually, the blue economy differs from the broader ocean economy, which encompasses all ocean-based activities, including non-sustainable industries such as offshore oil extraction and maritime transport. It is also distinct from the broader water economy, which encompasses freshwater systems, sanitation, agriculture, and watershed management [2,13].

Within this conceptual landscape, blue finance provides the financial foundation that enables the blue economy to function as a sustainability-oriented development model. It channels resources toward marine conservation, coastal resilience, and regenerative ocean-based activities, reinforcing long-term ecological stability [14]. Blue finance is characterized by its explicit ocean-linked purpose and measurable marine environmental outcomes, distinguishing it from wider sustainable or climate finance frameworks. A key distinction is that blue finance requires explicitly ocean-linked, measurable environmental outcomes, including gains in marine biodiversity, coastal resilience indicators, or enhancements to ecosystem services. In contrast, sustainable or green finance relies on broader ESG or climate metrics that may not capture marine-specific impacts.

Conceptual labels including “blue economy”, “ocean economy”, and “marine finance” are used with divergent scopes across disciplines, reflecting heterogeneous analytical traditions. This definitional inconsistency is a central source of conceptual fragmentation in the literature because it obscures the boundaries of what qualifies as a blue financial instrument and complicates the development of coherent theoretical and operational frameworks.

2.2. Financial Architecture of Blue Finance

Blue finance rests on a structured capital architecture that strategically integrates financial innovation with ocean sustainability objectives. It mobilizes a diversified portfolio of capital sources, including debt instruments like blue bonds and concessional loans, equity financing targeting high-impact sectors, blended finance mechanisms that de-risk investments, and targeted public subsidies [15,16]. This layered structure supports scalability by attracting both public and private investors and sustaining long-term capital flows for marine preservation and climate-resilient development. Debt instruments offer stable returns that appeal to institutional investors [17], while equity financing fosters innovation in areas including sustainable aquaculture, green shipping, and marine renewable energy [3]. Blended finance acts as a catalytic layer, leveraging concessional resources to mobilize private capital and enhance project bankability [18]. This multidimensional structure provides the financial backbone for scaling blue investments and aligning capital allocation with sustainable ocean-based growth.

2.3. Barriers to Blue Finance

Despite its growing prominence, blue finance faces persistent structural and systemic barriers. A fragmented regulatory environment, the absence of standardized taxonomies, and weak incentives discourage large-scale capital mobilization [4,19]. The scarcity of investment-ready projects and the lack of risk mitigation mechanisms further reduce market attractiveness [20]. Limited knowledge infrastructure and technical capacity also undermine the design of strategic investments [21].

Beyond financing constraints, these barriers generate conceptual fragmentation in academic research. Disparate regulatory frameworks and heterogeneous instruments have produced a scattered literature across multiple domains, limiting the consolidation of theoretical models and integrated investment strategies. This fragmented landscape complicates the development of coherent frameworks that can guide both market design and scholarly analysis.

2.4. Advancing the Enabling Environment for Sustainable Blue Finance

Overcoming these barriers requires coordinated regulatory innovation, credible financial architectures, and robust risk-sharing mechanisms. Securing fishing rights, enforcing environmental standards, phasing out harmful subsidies, and adopting standardized taxonomies are key institutional preconditions [22]. Financial innovations, including blue bonds linked to performance metrics, blended finance, and strategic public–private partnerships, help scale investments [23,24,25]. Insurance mechanisms introduce market discipline by directing capital toward resilient marine assets [26].

These measures not only create enabling conditions for capital flows but also shape research trajectories by concentrating academic attention on emerging instruments, governance frameworks, and policy architectures. The evolving enabling environment thus plays a critical role in structuring thematic clusters in the blue finance literature and reinforcing its strategic coherence.

2.5. Bibliometric Foundations of Blue Finance Research

Blue finance lies at the intersection of sustainable finance, ocean governance, and environmental economics. This interdisciplinary configuration has produced a fragmented academic landscape where key insights are scattered across policy studies, financial economics, marine science, and environmental governance. The coexistence of heterogeneous analytical traditions, non-standardized terminology, and divergent methodological approaches has resulted in dispersed knowledge, weak conceptual integration, and limited cumulative theorization. These structural inconsistencies constrain the field’s capacity to articulate shared conceptual boundaries, develop integrated investment frameworks, and maintain theoretical continuity.

Bibliometric analysis provides a systematic and rigorous means of addressing these challenges. By mapping influential authors, identifying thematic clusters, and tracing intellectual evolution [11,27], it offers a structured platform for synthesizing dispersed evidence and clarifying the conceptual architecture of blue finance. Moreover, temporal science-mapping reveals how the field has progressed from early conservation-oriented financing mechanisms to more sophisticated instruments, including blended finance, blue bonds, and integrated governance frameworks [28,29]. An integrated bibliometric synthesis is therefore indispensable for sorting out the field’s conceptual ambiguities, reflecting on the trajectory of academic progress, and guiding future research directions in blue finance.

3. Methodology and Data

3.1. Methodology

This study employs a rigorous bibliometric methodology to systematically structure and analyze the intellectual and conceptual architecture of the blue finance literature. The methodological framework is anchored in two complementary pillars: performance analysis and science mapping [11]. These pillars offer distinct yet synergistic perspectives that, when combined, provide a comprehensive understanding of how the field has been structured, expanded, and interconnected over time. This dual design enables a more integrated knowledge than descriptive bibliometric analyses alone can provide.

Performance analysis establishes the quantitative foundation by assessing research productivity and scholarly influence. It captures the field’s intellectual structure through a systematic examination of authorship patterns, institutional contributions, journal impact, and geographical distribution. This stage is implemented using the Bibliometrix package (v4.2.2) and its Biblioshiny interface in the R environment, enabling the extraction and visualization of key bibliometric indicators, including publication trajectories, author impact, source prominence, and thematic dynamics [27].

Science mapping complements this by revealing the field’s conceptual architecture. It examines relational structures through co-occurrence analysis, bibliographic coupling, and network mapping at the document, author, and keyword levels, identifying thematic clusters and intellectual linkages that distinguish core domains from emerging research fronts. VOSviewer v1.6.20 supports this stage by enabling advanced visualization of co-citation, co-authorship, and keyword co-occurrence networks [30]. This integrated strategy enhances interpretative depth by aligning quantitative performance metrics with conceptual network structures, resulting in a more robust and coherent mapping of the field [31].

Together, performance analysis and science mapping form a coherent methodological architecture that reveals intellectual foundations, delineates conceptual frontiers, and identifies structural gaps and thematic trajectories, positioning blue finance as a dynamic research domain within sustainable finance.

3.2. Data

Constructing a solid methodological foundation required selecting a database capable of supporting systematic and reproducible bibliometric analysis. Scopus was chosen for its broad coverage, rigorous selection, and standardized indexing, making it a benchmark for bibliometric research in finance and sustainability. Its scope and controlled vocabulary make it particularly suitable for mapping the evolving landscape of blue finance [32,33].

The data collection and selection process followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) framework [34]. This structured protocol ensured transparency and reproducibility through four sequential stages: identification, screening, eligibility, and inclusion (Figure 1). Applying PRISMA at the retrieval stage enhanced methodological clarity and minimized selection bias. The identification phase was based on a keyword strategy informed by seminal and recent contributions on blue finance, designed to capture both conceptual foundations and emerging dimensions. The set of keywords included the main financial instruments and thematic indices most commonly associated with blue finance, ensuring conceptual relevance while avoiding peripheral topics. The document searches targeted publications containing the terms “blue finance” and related concepts in titles, abstracts, and keywords, ensuring breadth and precision in retrieval. The search was restricted to English-language research articles and review papers indexed in Scopus up to 2025. Non-research materials, including proceedings, editorials, and letters, were excluded to ensure thematic and methodological consistency. The corpus was further narrowed to the subject areas of Economics, Econometrics and Finance, and Business, Management and Accounting, ensuring alignment with the research objectives. This process yielded 405 initial records, of which 217 were retained after manual screening based on explicit conceptual criteria. Studies were excluded if they did not engage with financial mechanisms, capital flows, investment instruments, or ocean-linked financing structures; when their marine focus was ecological, conservation-oriented, governance-based, or technical rather than financial; or when keyword matches reflected non-financial uses of the term “blue” in fields including biology, fisheries, oceanography, or coastal engineering. This explicit screening protocol ensures conceptual precision and prevents thematic drift. To further verify the robustness of the dataset, a sensitivity test was conducted using an extended search that included broader marine-policy and coastal-management terms, including “marine conservation finance,” “ocean investment,” and “integrated coastal zone management.” Although this expanded query identified additional publications, a systematic manual screening based on predefined conceptual and financial inclusion criteria confirmed that these documents focused on conservation, ecological restoration, or spatial planning without engaging with financial instruments, capital-mobilization mechanisms, or ocean-linked investment structures. Including such papers would have diluted the review’s financial focus, and none met the criteria for blue finance in this study. These results confirm the validity and conceptual precision of the initial search strategy. Together, these procedures establish a transparent and replicable selection process and verify that the final dataset robustly reflects the conceptual boundaries of blue finance.

4. Results

4.1. Performance Analysis

4.1.1. Data Overview

An overview of key descriptive indicators is presented in

Table 1. Data Overview.

Description	Results	Description	Results
Main information about data		Authors
Database	Scopus	Authors	894
Timespan	2007:2025	Authors of single-authored docs	26
Sources (Journals, Books, etc.)	114	Authors collaboration
Documents	217	Single-authored docs	28
Annual Growth Rate %	22.03	Co-Authors per Doc	4.79
Document Average Age	4.22	International co-authorships %	40.09
Average citations per doc	36.9	Document types
References	7832	Article	200
Document contents		Article; Book chapter	3
Keywords Plus (ID)	932	Review	14
Author’s Keywords (DE)	824

, highlighting the field’s size, growth trajectory, and collaborative structure. The bibliometric dataset, derived from Scopus and covering the period 2007–2025, provides a structured lens on the evolution and consolidation of this emerging domain. It comprises 217 publications across 114 sources, authored by 894 researchers, reflecting the steady expansion of scholarly engagement. The field exhibits a robust upward trajectory, with an annual growth rate of 22.03% and an average document age of 4.22 years, underscoring its recent emergence and rapid development. Taken together, these patterns indicate not only quantitative growth but also the gradual consolidation of Blue Finance as an interconnected, interdisciplinary research domain. This sustained growth reflects both the increasing academic interest in blue finance and its progressive institutional consolidation. Collaboration is a defining feature: only 28 single-authored papers are identified, with an average of 4.79 co-authors per document. Moreover, 40.09% of publications involve international co-authorship, revealing strong global research linkages and the formation of transnational scholarly networks. The collection is dominated by 200 research articles, complemented by three book chapters and 14 review papers. Intellectual diversity is evident, with 7832 references, 932 Keywords Plus, and 824 Author Keywords, underscoring the field’s thematic richness and interdisciplinary scope.

The temporal evolution analysis concerning publications on blue finance, as illustrated in Figure 2, reveals a clear three-phase trajectory shaped by major global milestones in ocean sustainability and finance. The early stage (2007–2013) is characterized by minimal output, with fewer than five publications annually, reflecting the absence of a structured discourse on blue finance. This limited activity coincided with the global financial crisis, which redirected research priorities toward macroeconomic stabilization. Although the 2012 Rio + 20 Conference formally introduced the concept of the blue economy, it did not immediately stimulate academic growth. The transitional phase (2014–2018) marks a period of modest but uneven expansion, as growing environmental pressures and climate risks increasingly intersect with financial narratives, laying the groundwork for thematic diversification but without a cohesive research architecture. A pronounced structural break emerges after 2018, with publication activity accelerating sharply. Major milestones, including the Nairobi Sustainable Blue Economy Conference and the Seychelles sovereign blue bond, catalyzed academic engagement, reinforced by the EU Sustainable Blue Economy Strategy and post-pandemic sustainability initiatives. Annual outputs more than doubled after 2018, climbing from 15 publications in 2019 to 36 in 2025. This inflection point reflects the crystallization of blue finance as a distinct, globally networked, and strategically positioned research domain.

4.1.2. Key Journals

The evolution of publications across the five most productive sources is depicted in Figure 3, revealing a clear and structured hierarchy within the blue finance literature. Marine Policy dominates with over 40 cumulative publications by 2025 and a steep post-2018 acceleration, followed by Journal of Cleaner Production and Environment, Development and Sustainability, reinforcing the field’s anchoring in sustainability science. Modest but steady growth from Ocean & Coastal Management and Frontiers in Marine Science signals interdisciplinary traction. At the same time, negligible output from business-oriented journals highlights a critical gap in financial-economic integration. This concentration of outputs in environmental and policy-oriented journals reflects the origins of blue finance in governance and conservation debates while pointing to future opportunities for expansion into finance-focused outlets.

The hierarchy of influential sources in blue finance research is illustrated in

Table 2. The 10 most impactful sources on Blue Finance.

Source	h_index	g_index	m_index	TC	NP	PY_start
Marine policy	20	40	1.053	1627	44	2007
Journal of cleaner production	14	20	1.273	885	20	2015
Environment, development and sustainability	5	9	0.5	88	10	2016
Frontiers in marine science	4	4	0.667	141	4	2020
Ocean and coastal management	4	4	0.64	174	4	2015
Business strategy and development	3	4	0.5	119	4	2020
Investment management and financial innovations	3	3	0.375	15	3	2018
Nature communications	3	4	0.429	925	4	2019
Applied economics letters	2	2	0.125	5	2	2010
Aquatic conservation: marine and freshwater ecosystems	2	2	0.222	129	2	2017

Notes: TC = Total Citations; NP = Number of Publications; PY_start = Starting Publication Year.

, which also introduces the core bibliometric performance indicators used throughout this analysis: total citations (TC), number of publications (NP), year of first publication (PY_start), h-index, m-index, and g-index. The h-index measures productivity and impact, the m-index adjusts the h-index by active years to allow for time-normalized comparisons, and the g-index captures the concentration of citations among core contributions. Marine Policy leads with an h-index of 20 and 1627 total citations (TC), reflecting its foundational role since 2007. Journal of Cleaner Production follows (h = 14, TC = 885), while Environment, Development and Sustainability, though newer (PY_start = 2016), shows vigorous citation intensity (m_index = 0.5). Frontiers in Marine Science (PY_start = 2020) displays early promise despite low output. The limited presence of business and finance journals indicates a critical thematic gap that could shape future research directions. This journal hierarchy mirrors the historical policy-oriented roots of blue finance while also signaling potential for future expansion into finance-focused outlets.

4.1.3. Most Prolific Authors

Prolific author analysis offers critical insights into the intellectual leadership, collaborative networks, and emerging thematic directions shaping the blue finance literature.

Table 3. The most productive author’s impact.

Author	h_index	g_index	m_index	TC	NP	PY_start
Sumaila Ussif Rashid	5	7	0.714	492	7	2019
Benzaken Dominique	3	4	0.6	153	4	2021
Crona Beatrice Irene	3	4	0.375	247	4	2018
Hearn Bruce Allen	3	5	0.188	32	5	2010
Kuwae Tomohiro	3	3	0.429	864	3	2019
Lovelock Catherine E.	3	3	0.3	1459	3	2016
Thiele Torsten	3	5	0.333	386	5	2017
Walsh Melissa	3	4	0.375	146	4	2018
Abdallah Patrízia Raggi	2	3	0.4	132	3	2021
Alkoyak-Yildiz Meltem	2	2	1	7	2	2024

Notes: TC = Total Citations; NP = Number of Publications; PY_start = Starting Publication Year.

ranks the ten most influential authors based on total citations (TC), number of publications (NP), year of first publication (PY_start), and citation impact metrics. These indicators reveal both the intensity and the temporal dynamics of scholarly contributions in the field. The concentration of citations among a small group of prominent authors underscores the centralization of intellectual leadership. At the same time, the presence of emerging scholars suggests the field’s gradual diversification.

Based on these impact metrics, Ussif Rashid Sumaila emerges as the most influential author. Since 2019, he has published seven papers, accumulating 492 citations, with an h-index of 5, g-index of 7, and m-index of 0.714. As Professor and Director at the University of British Columbia, he has anchored the intellectual core of blue finance and shaped its interdisciplinary foundations through his work on fisheries economics, subsidy reform, and marine governance. Dominique Benzaken ranks second, with four publications, 153 citations, and an h-index of 3 since 2021. Affiliated with ANCORS at the University of Wollongong, her research operationalizes blue finance through governance innovation, notably via the Seychelles Blue Bond, which stands as a landmark in the field. In third position, Beatrice Irene Crona has four publications, 247 citations, and an h-index of 3 since 2018. At the Royal Swedish Academy of Sciences and Stockholm University, her contributions bridge socio-ecological systems and global financial flows, highlighting how capital and governance intersect in shaping ocean sustainability. Bruce Allen Hearn, with five outputs since 2010 and 32 citations, is among the early academic contributors. His research at the University of Sussex explores financial market structures and macroeconomic mechanisms driving investment in ocean-related assets. Tomohiro Kuwae exhibits remarkable citation intensity, with three publications and 864 citations, underscoring his leadership in blue carbon sequestration research that underpins emerging carbon crediting mechanisms. Catherine E. Lovelock, Professor at the University of Queensland, leads in citation impact with 1459 citations and three publications, reflecting the centrality of mangrove and seagrass ecosystems in sustainable finance frameworks. Torsten Thiele, Senior Researcher at RIFS Potsdam, contributes five publications and 386 citations, advancing innovative approaches to blue bonds, blended finance, and ocean governance. Melissa Walsh, with four publications and 146 citations since 2018, has focused on integrating financial mechanisms with conservation governance, consolidating the field’s applied dimension. Patrízia Raggi Abdallah (132 citations, 3 publications) and Meltem Alkoyak-Yildiz (7 citations, 2 publications) represent a new generation of scholars whose strong m-index values signal early influence and rising scholarly visibility in the field.

4.1.4. Most Influential Documents

Analyzing citation patterns reveals conceptual concentrations that have defined the intellectual trajectory of blue finance.

Table 4. The most cited document.

Cited Document	Source	TC	TC per Year
Macreadie et al. (2019) [35]	Nature Communications	782	111.71
Gill et al. (2017) [37]	Nature	712	79.11
Bayraktarov et al. (2016) [36]	Ecological Applications	663	66.30
Claudet et al. (2020) [39]	One Earth	215	35.83
Sumaila et al. (2019) [9]	Marine Policy	213	30.43
Douvere et al. (2007) [38]	Marine Policy	196	10.32
Keen et al. (2018) [40]	Marine Policy	171	21.38
Kvaal & Nobes (2010) [41]	Accounting and Business Research	165	10.31
Winther et al. (2020) [6]	Nature Ecology & Evolution	154	25.67
Garcia Rodrigues et al. (2017) [21]	One Ecosystem	143	15.89
Xu et al. (2015) [42]	Journal Of Cleaner Production	135	12.27

lists the ten most influential contributions ranked by total citations (TC) and TC per year. Collectively, these works converge around three interconnected research pillars: (i) blue carbon and ecosystem valuation, (ii) governance and financing mechanisms, and (iii) policy and institutional frameworks. Within the blue carbon and ecosystem valuation stream, Macreadie et al. (2019) [35] and Bayraktarov et al. (2016) [36] pioneered the economic assessment of coastal ecosystems, reframing restoration and carbon sequestration as investable assets in climate finance. Garcia Rodrigues et al. (2017) [21] extended this perspective by incorporating cultural ecosystem services into marine valuation models, broadening the socio-economic foundation of blue finance. The governance and financing mechanisms cluster is driven by studies including Gill et al. (2017) [37] and Douvere et al. (2007) [38], which emphasize how governance effectiveness and marine spatial planning underpin the success of blue investment frameworks. Sumaila et al. (2019) [9] added a fiscal dimension, showing how subsidy flows and financial incentives shape the architecture of ocean finance systems. Finally, the policy and institutional frameworks dimension is consolidated through the works of Claudet et al. (2020) [39], Keen et al. (2018) [40], and Winther et al. (2020) [6], who advocate for integrated science–policy–finance approaches to operationalize the blue economy. Complementarily, Kvaal & Nobes (2010) [41] reveal how accounting and reporting standards enable transparency and accountability, providing a structural foundation for credible blue finance markets. Overall, these seminal studies chart the intellectual evolution of blue finance from ecological valuation to institutional design, reflecting the field’s transition toward a coherent interdisciplinary paradigm.

4.2. Science Mapping

Science mapping provides a systematic lens through which the structural configuration of scientific knowledge can be explored and visualized. It seeks to uncover the intellectual, conceptual, and social linkages that define and shape a research domain [43]. In contrast to performance analysis, which focuses primarily on measuring scholarly output, science mapping emphasizes the interconnectedness and structural patterns linking key scientific entities, including authors, keywords, publications, and citations. This macroscopic perspective highlights how research communities form, how ideas evolve, and how knowledge architectures consolidate over time. This allows for a deeper understanding of how knowledge is organized, diffused, and transformed [11,27].

In this study, co-word analysis was selected as the primary science mapping technique. This content-based approach captures the semantic structure of a research domain by jointly modeling the appearance of keywords across publications. Unlike citation-based methods, this technique emphasizes the lexical and conceptual content of scholarly outputs, revealing how ideas are articulated and connected within the literature [44,45]. This methodological choice is particularly relevant in the context of Blue Finance, where conceptual boundaries remain fluid and are actively shaped through thematic experimentation and cross-sectoral integration. By analyzing co-occurring author keywords, this analysis enables the identification of conceptual clusters that map the conceptual backbone of Blue Finance. This approach reveals both the central paradigms structuring the field and the peripheral themes that signal emerging niches and future research trajectories. It highlights how core themes, peripheral niches, and emerging trajectories are structured and interrelated, offering a fine-grained semantic perspective on the field’s organization [46]. A keyword co-occurrence network, illustrated in Figure 4, visualizes the conceptual structure of research on blue finance. The centrality and typographic prominence of “blue economy” underscore its role as the foundational construct around which key thematic clusters coalesce. Notably, the prominence and proximity of “sustainable finance,” “blue bonds,” and “green bonds” suggest strong conceptual linkages, reflecting a scholarly emphasis on financial instruments that advance ocean sustainability. This financial cluster highlights the anchoring of blue finance in market-based mechanisms and the gradual integration of ocean finance into sustainable investment strategies. The co-occurrence of “climate change,” “marine conservation,” and “marine spatial planning” further underscores an integrated research agenda that bridges environmental governance and economic policy. Geographic markets, including “China” and “Seychelles,” point to case-specific investigations, while the presence of “COVID-19” indicates a growing effort to contextualize blue finance within global systemic shocks. Beyond descriptive mapping, the network configuration shows an intense concentration around financial-ecological nexus concepts, indicating that Blue Finance is increasingly organized around hybrid constructs that integrate environmental risk, governance tools, and financial design. Together, these patterns depict an interdisciplinary knowledge structure characterized by a substantial environmental–financial nexus, geographic diversification, and responsiveness to external shocks, positioning blue finance as a rapidly consolidating frontier in sustainability science.

4.2.1. Thematic Clustering and Conceptual Interpretation

Coupling co-word mapping with targeted content analysis transcends descriptive visualization to reveal the cognitive architecture of Blue Finance research. This integrated approach shifts the analytical lens from structural detection to conceptual interpretation, uncovering how thematic clusters are conceptually constructed, discursively mobilized, and dynamically reshaped within the scholarly corpus. By articulating network topology with contextual content reading, it clarifies the positioning, internal coherence, and evolutionary logic of core knowledge domains. This enables a deeper understanding of how emerging research trajectories consolidate into stable thematic paradigms and how peripheral debates evolve into recognized conceptual frontiers. To operationalize this framework, the co-word network was constructed and visualized in VOSviewer with a minimum occurrence threshold of four, ensuring analytical precision while minimizing lexical noise. Ambiguous or overly generic terms were systematically excluded, and semantically related expressions were manually merged to enhance conceptual coherence. This refinement yielded a robust set of 26 core keywords that define the conceptual backbone of the Blue Finance research domain. Figure 5a illustrates the resulting network structure: 20 salient terms organized into three interconnected clusters, linked by 51 edges with a total link strength of 80, indicating a moderate-to-high density network, suitable for identifying cohesive thematic structures. Node size reflects keyword frequency, while edge thickness signifies co-occurrence intensity. Central anchors, including “blue economy,” “blue finance,” “blue bonds,” “sustainable finance,” and “climate change,” delineate the field’s core semantic architecture and act as connective pivots across thematic dimensions. Figure 5b presents a temporal overlay visualization that traces the field’s evolution through successive phases. The initial stage (2007–2013) is dominated by ecological and climatic concerns, emphasizing environmental risk, resource scarcity, and ecosystem valuation. The transitional phase (2014–2018) introduces governance-oriented concepts, including “sustainability,” “marine conservation,” and “spatial planning,” signaling institutional consolidation. From 2019 onward, the center of gravity shifts toward “blue economy” and related financial instruments, while the latest period (2022–2025) is marked by the emergence of “blue bonds,” “equity,” “Seychelles,” and governance-linked concepts including “blue justice.” This three-phase trajectory encapsulates the conceptual maturation of Blue Finance, reflecting its transformation from an ecologically rooted idea to a financially structured and policy-integrated research paradigm. Overall, the clustering results confirm that climate–environmental risk, sustainability-governance integration, and financial innovation constitute the three structurally central themes around which the Blue Finance literature is organized.

To ensure analytical transparency, the VOSviewer clustering results were systematically examined through a structured interpretation protocol that involved a close reading of cluster-associated documents to identify recurrent conceptual patterns, thematic boundaries, and cross-cluster linkages. This interpretive refinement enhances analytical precision, mitigates descriptive redundancy, and strengthens the conceptual validity of cluster classification. It yields a coherent and methodologically rigorous representation of the conceptual organization of Blue Finance scholarship, as detailed in

Table 5. Thematic clusters.

Cluster	Words	Topic
1	Blue economy, Blue finance, Blue bonds, Seychelles, Equity, COVID-19, Fisheries	Innovative Blue Finance Mechanisms and Economic Resilience
2	Sustainability, Sustainable development, Sustainable finance, Blue justice, Marine conservation, Marine spatial planning, Conservation finance	Blue Finance for Sustainability Integration and Governance
3	Climate change, Water footprint, Water scarcity, Ecosystem services, China	Climate–Environmental Interfaces in Blue Finance

. To complement this structural mapping, Gephi software (version 0.10.1) was employed to visualize trend-based, capturing the temporal and relational evolution of knowledge structures within and across clusters, as summarized in

Table 6. Trend themes per cluster.

Label	Cluster	Links	Occur	Avg Pub Year	Avg n. Citations
Seychelles	1	7	4	2024.0	1.0571
blue bonds	1	6	10	2023.6	0.7660
blue finance	1	9	10	2023.5	1.2522
Equity	1	4	7	2023.4	0.8795
COVID-19	1	3	4	2022.8	0.6041
Fisheries	1	6	4	2022.8	0.4197
blue economy	1	14	30	2022.6	1.4020
blue justice	2	3	4	2023.8	1.0995
sustainable finance	2	9	9	2023.0	1.8949
sustainable development	2	3	4	2022.5	0.8727
marine conservation	2	5	6	2021.2	0.6707
Sustainability	2	7	9	2020.4	1.7376
conservation finance	2	2	4	2020.2	0.7365
marine spatial planning	2	6	7	2019.7	0.9074
water footprint	3	2	10	2021.7	0.9139
water scarcity	3	2	4	2021.5	0.9511
ecosystem services	3	2	4	2021.0	0.7486
climate change	3	5	9	2020.9	1.2451
China	3	2	5	2019.6	0.7620

. In this context, thematic clusters delineate the field’s structural foundations. At the same time, trend-based trace their conceptual trajectories, providing a comprehensive analytical framework for decoding their cognitive architecture and evolutionary dynamics.

4.2.2. Thematic Trends and Research Topics

Grounded in co-word analysis that delineates the field’s conceptual structure, a complementary content analysis was conducted to enhance interpretive depth and contextual precision. This combined approach identifies dominant and emerging research fronts while revealing how core concepts are defined, operationalized, and interlinked across the corpus. By moving beyond descriptive mapping, the analysis offers a strategic synthesis of conceptual patterns and thematic evolution, advancing Blue Finance toward greater theoretical and policy relevance [47,48].

Research Topic 1: Innovative Blue Finance Mechanisms and Economic Resilience

Cluster 1 reflects the financial innovation pillar of Blue Finance, emerging as the core thematic structure within the co-word network. With an average publication year around 2023 and a dense web of conceptual linkages anchored by the term “blue economy,” this cluster illustrates the convergence of research streams on financial innovation, ocean governance, and economic resilience. The prominence of “blue economy” (occurrence = 30, links = 14), together with “blue finance” (10, 9), “blue bonds” (10, 6), and “Seychelles” (4, 7), reveals a highly cohesive conceptual core, reflecting the growing scholarly interest in financing mechanisms dedicated to sustainable marine development [49,50].

A closer examination of this cluster shows a growing interest in the evolving discourse on ocean finance. Instruments including blue bonds, blended finance structures, and debt-for-nature swaps are increasingly discussed beyond their early experimental framing, reflecting their potential to mobilize capital over extended horizons [51,52]. The 2018 Seychelles sovereign blue bond issuance exemplifies this transition, illustrating how concessional and market-based financing can be strategically combined to support marine spatial planning, fisheries management, and ecosystem protection. Collectively, these instruments represent the expanding role of innovative finance in supporting ocean resilience.

The co-occurrence of terms including “COVID-19” and “fisheries” suggests that some contributions address how external shocks affect ocean-based sectors within blue finance discussions. Blue finance is examined in some studies for its potential to serve as a countercyclical instrument that can stabilize critical ocean-based sectors during external shocks, including pandemics and climate-related disruptions [53,54]. This emphasis aligns with broader evidence highlighting the potential of targeted ocean finance to strengthen both economic and ecological resilience in vulnerable economies [4]. In parallel, critical literature raises concerns about governance, transparency, and distributive equity, emphasizing the fair allocation of benefits and responsibilities among stakeholders [49]. Scholars highlight the risks of bluewashing, where symbolic commitments exceed verifiable ecological outcomes [55], and question the limited debt relief achieved under current financing models [51], underscoring the need for robust accountability mechanisms and standardized impact metrics.

Recent contributions position blue bonds and the Seychelles as emblematic instruments of innovative blue finance. The 2018 issuance marks a pivotal moment in aligning capital markets with marine conservation and sustainable development objectives. Blue bonds operationalize blended finance by mobilizing concessional resources, private capital, and ESG principles to strengthen fisheries resilience and marine spatial planning [49,50]. Building on this momentum, Blue Sukuk has emerged as a complementary mechanism that embeds Islamic finance principles to expand investor participation and deepen conservation funding [56]. Their growing prominence illustrates the field’s evolution toward diversified, inclusive, and impact-oriented financing pathways. While promising, their transformative capacity hinges on transparent governance, rigorous monitoring, and equitable distribution [51,55]. Collectively, these contributions highlight recurrent themes in the literature on innovative blue finance and its emerging instruments, reinforcing the significance of this research stream within broader debates on financing ocean resilience and sustainable development.

Although innovative instruments, including blue bonds, blended finance, and debt-for-nature swaps, are widely promoted, critical studies warn that they may intensify fiscal dependence, create “blue debt,” and enable bluewashing when impact verification is weak. These concerns reflect a broader debate in conservation finance, which questions whether market-based tools can generate durable ecological outcomes in contexts of institutional fragility and inequality. Their transformative potential, therefore, depends less on financial innovation itself than on governance legitimacy, transparent accountability, and equitable benefit-sharing.

Research Topic 2: Blue Finance for Sustainability Integration and Governance

Cluster 2 reflects the sustainability integration pillar of Blue Finance and is anchored primarily around the terms “sustainable finance” and “sustainability”, which exhibit the highest occurrences and citation intensity within this thematic configuration. The cluster also includes “blue justice,” “marine conservation,” “marine spatial planning,” “sustainable development,” and “conservation finance.” This constellation of concepts points to an emerging consolidation in the literature, in which sustainability concerns are increasingly embedded in discussions of blue finance and its associated governance mechanisms. Rather than suggesting a definitive functional role, the co-occurrence structure indicates a progressive integration of ecological, financial, and institutional dimensions in recent scholarship. It illustrates how conservation is increasingly framed not only as an environmental imperative but also as a strategic financial and governance endeavor [39,57]. “Sustainable finance” (links = 9; occurrences = 9; average publication year = 2023.0) emerges as the conceptual anchor, reflecting its central role in discussions on mobilizing capital for marine sustainability. Innovative financial instruments, including impact investments, biodiversity offsets, insurance mechanisms, and blue carbon credits, are recurrent mechanisms in the literature for strengthening long-term conservation financing. These instruments are frequently discussed alongside governance frameworks, notably marine spatial planning and co-management models, reflecting a thematic association among financial flows, ecological objectives, and institutional capacity-building [38,57,58,59].

Equally integral to this thematic structure is “blue justice” (links = 3; occurrences = 4; average publication year = 2023.8; average citations = 1.0995), which foregrounds social fairness, inclusivity, and community rights. Beyond its normative scope, it directly shapes resource allocation, benefit distribution, and participatory mechanisms, embedding fairness as a core operational principle of blue finance [60]. Taken together, the co-occurring terms indicate that sustainability forms the conceptual backbone of Cluster 2, with governance and equity emerging as closely associated themes in the relevant scholarship. Studies consistently highlight how sustainable finance frameworks, governance arrangements, and justice principles intersect in discussions of transparency, participation, and social fairness, reinforcing the prominence of these dimensions in blue finance research.

Research Topic 3: Climate–Environmental Risk Interfaces in Blue Finance

Cluster 3 represents the foundational thematic strand of Blue Finance, centered on “climate change” and “water footprint,” which exhibit the highest co-occurrence strength and citation intensity in the network. With an average publication year around 2021 this cluster reflects earlier scholarly attention to environmental risk, resource security, and the financial valuation of ecosystem services. It captures an initial stage in which blue finance began to be framed in relation to climate-induced vulnerabilities and ecological stress.

The thematic configuration highlights the convergence between climate risk, resource security, and environmental finance mechanisms. A significant body of literature demonstrates that climate-driven stressors reshape both ecological systems and economic structures, particularly in regions highly exposed to environmental degradation and resource scarcity [61]. Within this nexus, ecosystem services emerge as a pivotal analytical construct, linking environmental stress to the valuation of natural capital and the translation of ecological vulnerability into measurable financial risks. This framing marks a conceptual shift from traditional resource management to adaptive, finance-based strategies for climate resilience. Recent contributions show a growing tendency to frame environmental risks as both systemic financial pressures and catalysts for finance-enabled resilience strategies embedded within sustainability frameworks [62]. Trend analysis identifies “water footprint” (links = 2; occurrences = 10) as the key anchor of this cluster, signaling intensified scholarly focus on integrating environmental risk metrics into climate adaptation and sustainable finance models [63,64]. Collectively, this cluster underscores the foundational role of climate–environmental risk in shaping the conceptual roots of Blue Finance. It lays the conceptual groundwork for subsequent research streams in sustainability integration and financial innovation, positioning environmental risk as both a catalyst and a connective axis for the field’s theoretical and practical evolution.

A parallel strand of critical literature questions the growing financialization of ecosystem services within this research stream. While natural capital valuation and blue carbon credits are promoted as mechanisms to mobilize conservation finance, scholars argue that translating ecological functions into investment assets risks reducing complex socio-ecological processes to marketable units of value [65]. The legitimacy of these valuation practices is further challenged by scientific uncertainty, methodological arbitrariness, and power asymmetries that privilege investors and intermediaries over local communities. These critiques underscore that the investment framing of ecosystem services is not a neutral extension of environmental finance but a contested transformation with ethical, distributive, and epistemic implications. Understanding when and for whom this financialization generates genuine ecological and social benefits remains a central challenge for future blue finance scholarship.

4.2.3. Research Agenda and Challenges for the Blue Finance Frontier

Drawing on the structural patterns and knowledge gaps identified through bibliometric and science-mapping analysis, Table 7 proposes a forward-looking research agenda to consolidate Blue Finance as both a platform of financial innovation and a catalyst for sustainability transitions. This agenda integrates conceptual, methodological, and operational priorities to bridge the persistent divide between financial mechanisms, environmental governance, and climate resilience. Collectively, these research directions delineate the next frontiers of Blue Finance, where sustainability, innovation, and resilience converge to shape the evolution of ocean investment research.

The first axis, Innovative Blue Finance Mechanisms and Economic Resilience, calls for a transition from descriptive analyses of blue bonds, Blue Sukuk, blended finance, and debt-for-nature swaps toward rigorous, impact-oriented evaluation frameworks. Persistent governance and impact-reporting gaps in early sovereign blue bond implementations [66] reinforce this need, and future inquiries must develop standardized models for assessing ecological and socioeconomic returns while embedding equity, governance, and transparency principles. Advancing risk-adjusted valuation systems and unified monitoring protocols can strengthen investor confidence and accountability. Expanding blended finance and credit enhancement mechanisms remains central to mobilizing private capital, yet fragmented regulation and capacity asymmetries continue to constrain scalability.

The second axis, Blue Finance for Sustainability Integration and Governance, emphasizes the institutionalization of sustainability and blue justice principles within marine financial architectures. The persistent underfunding of marine protected areas and fragmented governance structures hinder implementation. Future studies should advance hybrid financing models, aligning philanthropic, public, and private resources to achieve durable conservation outcomes. Embedding Blue-ESG metrics into investment decision-making, reinforcing co-management frameworks, and mainstreaming equity-based accountability will enhance the alignment between ecological stewardship and financial governance.

The third axis, Climate-Environmental Nexus and Finance-Driven Resilience, underscores the urgency of embedding climate stress indicators and environmental risk metrics within blue finance architectures. Despite rising awareness of climate-induced vulnerabilities, empirical validation and model integration remain limited. Research should explore how blue bonds, public–private partnerships, and blue carbon credits can operate as adaptive finance instruments that reinforce systemic resilience. Integrating geospatial analytics, climate-risk modeling, and sustainability indices will enable evidence-based, context-sensitive financial strategies, particularly in emerging and coastal economies.

Taken together, these three axes outline a research agenda that reflects both the conceptual expansion and the operational maturation of Blue Finance. Nonetheless, several challenges persist, including non-standardized impact metrics, fragmented regulation, limited empirical validation of instruments, and persistent inequities in benefit-sharing, especially in vulnerable coastal and island economies. Across these three axes, a critical research challenge concerns the growing financialization of ocean resources. As conservation finance mechanisms increasingly treat ecosystem functions and carbon-sequestration capacities as investment assets, scholars highlight unresolved ethical, distributive, and epistemic concerns. This transformation raises fundamental questions about who defines value, who captures benefits, and how market-based instruments reshape power relations within coastal communities. Addressing these tensions is essential for ensuring that blue finance contributes to genuine ecological resilience rather than reproducing social or environmental inequities. Overall, this research agenda defines the frontier of Blue Finance as a transformative space where financial systems evolve to serve ecological imperatives. It calls for a paradigmatic shift from fragmented experimentation to systemic integration, from descriptive mapping to measurable impact, and from isolated innovation to inclusive governance. Advancing this frontier demands cross-sectoral collaboration among scholars, investors, and policymakers to design transparent, adaptive, and equitable ocean finance ecosystems that sustain both economic prosperity and planetary well-being.

Table 7. Research Agenda for Blue Finance.

Research Topic	Research Gaps	References	Research Agenda	Sustainability Implementation Challenges
Topic 1: Innovative Blue Finance Mechanisms and Economic Resilience	− Limited causal evidence on the ecological and socio-economic impact of blue finance instruments (blue bonds, Blue Sukuk, blended finance, debt-for-nature swaps) − Weak integration of equity and governance dimensions − Lack of standardized risk–return/pricing frameworks for blue assets − Low private capital mobilization − Verification gaps and bluewashing risks − Over-reliance on case studies (Seychelles)	[4,49,50,51,52,53,55,56,67,68]	− Develop longitudinal impact evaluation to assess real outcomes (MPA coverage, stock status, income) − Build risk-adjusted valuation models and impact-linked pricing tools for blue assets − Strengthen governance, taxonomy alignment, and independent verification − Integrate equity and benefit-sharing protocols − Expand blended finance, Blue Sukuk, and credit enhancement mechanisms to mobilize private capital	− Fragmented regulatory frameworks − Weak MRV (Monitoring, Reporting, Verification) and disclosure systems for blue assets − High investor risk asymmetry and limited blue asset track records − Underdeveloped blue asset markets − Capacity gaps in SIDS − Limited access to affordable local finance
Topic 2: Blue Finance for Sustainability Integration and Governance	− Chronic underfunding of MPAs and conservation projects due to limited blue finance deployment − Fragmented governance and weak integration of blue justice principles within financing frameworks − Lack of standardized and scalable co-management financing models − Insufficient alignment between conservation objectives and financial structures − Uneven adoption of Blue-ESG disclosure standards	[39,57,58,59,60,69]	− Develop hybrid blue finance models combining public, philanthropic, and private capital to secure long-term conservation funding − Institutionalize equity and governance mechanisms within blue finance instruments − Strengthen financial sustainability assessment frameworks for MPAs and conservation assets − Advance integration of Blue-ESG metrics into financial decision-making and reporting − Foster adaptive co-management frameworks linking financial flows to measurable conservation outcomes	− Regulatory and governance fragmentation − Weak enforcement capacity and lack of harmonized standards for blue financing mechanisms − Overreliance on short-term donor funding − Limited investor interest in non-market conservation assets − Asymmetric capacities across regions and institutions
Topic 3: Climate–Environmental Interfaces in Blue Finance	− Limited integration of climate and environmental risk indicators into blue finance frameworks − Limited predictive modeling of climate-driven systemic risks for investment strategies − Weak empirical evidence on the effectiveness of blue finance instruments (blue bonds, PPPs, blue carbon finance) − Lack of standardized climate-risk metrics for disclosure and ESG alignment − Limited transferability of existing frameworks across developed and emerging economies	[22,62,63,64]	− Integrate climate-induced environmental stress indicators into blue finance architectures to strengthen risk-informed investment strategies − Expand empirical assessments of blue bonds, PPPs, and blue carbon credits as resilience-enhancing mechanisms − Develop standardized climate-risk metrics and disclosure frameworks aligned with ESG finance − Link financial innovation to adaptation and resilience objectives in marine and coastal systems − Foster policy coordination and incentive structures to scale capital mobilization for climate resilience	− Fragmented regulatory and governance frameworks − Weak MRV and disclosure systems for climate-related risks − Underdeveloped markets for resilience-oriented financial instruments − Investor uncertainty and asymmetrical risk perception − Limited institutional capacity and weak cross-sector coordination

Table 7. Research Agenda for Blue Finance.

Research Topic	Research Gaps	References	Research Agenda	Sustainability Implementation Challenges
Topic 1: Innovative Blue Finance Mechanisms and Economic Resilience	− Limited causal evidence on the ecological and socio-economic impact of blue finance instruments (blue bonds, Blue Sukuk, blended finance, debt-for-nature swaps) − Weak integration of equity and governance dimensions − Lack of standardized risk–return/pricing frameworks for blue assets − Low private capital mobilization − Verification gaps and bluewashing risks − Over-reliance on case studies (Seychelles)	[4,49,50,51,52,53,55,56,67,68]	− Develop longitudinal impact evaluation to assess real outcomes (MPA coverage, stock status, income) − Build risk-adjusted valuation models and impact-linked pricing tools for blue assets − Strengthen governance, taxonomy alignment, and independent verification − Integrate equity and benefit-sharing protocols − Expand blended finance, Blue Sukuk, and credit enhancement mechanisms to mobilize private capital	− Fragmented regulatory frameworks − Weak MRV (Monitoring, Reporting, Verification) and disclosure systems for blue assets − High investor risk asymmetry and limited blue asset track records − Underdeveloped blue asset markets − Capacity gaps in SIDS − Limited access to affordable local finance
Topic 2: Blue Finance for Sustainability Integration and Governance	− Chronic underfunding of MPAs and conservation projects due to limited blue finance deployment − Fragmented governance and weak integration of blue justice principles within financing frameworks − Lack of standardized and scalable co-management financing models − Insufficient alignment between conservation objectives and financial structures − Uneven adoption of Blue-ESG disclosure standards	[39,57,58,59,60,69]	− Develop hybrid blue finance models combining public, philanthropic, and private capital to secure long-term conservation funding − Institutionalize equity and governance mechanisms within blue finance instruments − Strengthen financial sustainability assessment frameworks for MPAs and conservation assets − Advance integration of Blue-ESG metrics into financial decision-making and reporting − Foster adaptive co-management frameworks linking financial flows to measurable conservation outcomes	− Regulatory and governance fragmentation − Weak enforcement capacity and lack of harmonized standards for blue financing mechanisms − Overreliance on short-term donor funding − Limited investor interest in non-market conservation assets − Asymmetric capacities across regions and institutions
Topic 3: Climate–Environmental Interfaces in Blue Finance	− Limited integration of climate and environmental risk indicators into blue finance frameworks − Limited predictive modeling of climate-driven systemic risks for investment strategies − Weak empirical evidence on the effectiveness of blue finance instruments (blue bonds, PPPs, blue carbon finance) − Lack of standardized climate-risk metrics for disclosure and ESG alignment − Limited transferability of existing frameworks across developed and emerging economies	[22,62,63,64]	− Integrate climate-induced environmental stress indicators into blue finance architectures to strengthen risk-informed investment strategies − Expand empirical assessments of blue bonds, PPPs, and blue carbon credits as resilience-enhancing mechanisms − Develop standardized climate-risk metrics and disclosure frameworks aligned with ESG finance − Link financial innovation to adaptation and resilience objectives in marine and coastal systems − Foster policy coordination and incentive structures to scale capital mobilization for climate resilience	− Fragmented regulatory and governance frameworks − Weak MRV and disclosure systems for climate-related risks − Underdeveloped markets for resilience-oriented financial instruments − Investor uncertainty and asymmetrical risk perception − Limited institutional capacity and weak cross-sector coordination

5. Discussion

Blue finance has rapidly gained prominence as a strategic mechanism for mobilizing capital toward sustainable and resilient ocean economies. Despite this growing momentum, the field’s conceptual landscape remains fragmented, limiting cumulative knowledge and strategic direction for future research and policymaking. This study conducts a comprehensive bibliometric analysis of 217 publications drawn from a PRISMA-guided Scopus dataset covering 2007–2025, employing Biblioshiny, VOSviewer, and Gephi to trace the conceptual evolution of blue finance, uncover its thematic architecture, and delineate its research front.

The temporal evolution of blue finance research demonstrates a structured three-phase trajectory reflecting the field’s gradual maturation. The embryonic stage (2007–2013) was marked by minimal scholarly output despite the global visibility of the Rio + 20 agenda. A transitional phase (2014–2018) followed, characterized by fragmented yet accelerating engagement as environmental and financial narratives began to converge. From 2018 onward, blue finance entered a consolidation phase, catalyzed by key milestones including the Nairobi Sustainable Blue Economy Conference, the Seychelles Blue Bond, and the EU Blue Economy Strategy. This acceleration signals a movement toward greater conceptual coherence rather than the complete crystallization of a unified domain while still reflecting alignment with broader sustainability and ocean governance transformations. However, this maturation remains uneven, as tensions between ecological objectives, financial incentives, and governance capacities persist in the current literature.

The journal landscape of blue finance reveals a structured yet discipline-skewed hierarchy, with clear evidence of post-2018 expansion and growing interdisciplinary convergence. Marine Policy, Journal of Cleaner Production, and Environment, Development and Sustainability dominate the field, confirming its deep anchoring in sustainability and marine governance. The rise of outlets including Frontiers in Marine Science and Ocean & Coastal Management indicates a shift toward greater cross-pollination between ecological and economic perspectives. Compared with Wang et al. [29], this analysis identifies a sharper post-2018 surge and stronger diversification of publication outlets, marking blue finance’s transition from a policy-oriented niche to an interdisciplinary research ecosystem. At the author and institutional levels, the results reveal a landscape of concentrated leadership coupled with emerging diversification. A small group of influential scholars, notably Ussif Rashid Sumaila, Dominique Benzaken, and Beatrice Irene Crona, anchor the field through pioneering contributions on blue carbon, ocean governance, and conservation finance. Consistent with Gehlot et al. [28], the clustering of citations among leading authors reflects the early-stage nature of collaborative networks. However, the growing visibility for emerging researchers with strong m-index values suggests early signs of generational renewal and expanding intellectual diversity. At the institutional level, the University of British Columbia, the University of Wollongong, and Stockholm University emerge as central nodes, reflecting Global North dominance but also the formation of broader interdisciplinary alliances shaping the evolution of blue finance.

The science-mapping analysis reveals that blue finance has evolved from a fragmented conceptual arena into a coherent and multidimensional research domain. The co-word network displays a dense and cohesive semantic structure in which “blue economy,” “blue finance,” and “blue bonds” form the intellectual nucleus linking financial innovation, ocean governance, and sustainability science [57,70]. This triadic configuration reflects a central thematic linkage within the field, the convergence of ecological imperatives, governance architectures, and financial mechanisms designed to mobilize capital for marine resilience.

Three interdependent thematic axes underpin this conceptual architecture. The first theme, the climate–environmental interface, lays the ecological groundwork for Blue Finance, framing it as a strategic mechanism to address climate-driven vulnerabilities and the growing scarcity of natural resources. Within this axis, the valuation of ecosystem services and the integration of environmental risk metrics emerge as analytical cornerstones linking natural capital to financial design [61,63,64]. The second, sustainability integration and governance, constitutes the normative and institutional core, embedding transparency, inclusivity, and co-management within marine finance frameworks through mechanisms including sustainable finance, marine spatial planning, and conservation finance [39,57,60]. The third, innovative financial mechanisms and economic resilience, defines the operational frontier of the field, translating ecological and governance principles into market-based instruments. Blue bonds, Blue Sukuk, and blended finance models have become pivotal in channeling capital toward marine conservation while enhancing macroeconomic stability [49,51,56]. What remains insufficiently explored is how these three thematic axes interact, particularly how environmental stress, institutional design, and financial innovation jointly influence investment behavior and long-term sustainability outcomes.

Beyond these structural foundations, emergent keyword hotspots, including blue bonds, sustainable finance, blue justice, and water footprint, mark areas of conceptual diffusion and accelerated scholarly activity. These focal zones highlight the intersection of financial innovation, governance reform, and climate adaptation, demonstrating a shift from normative advocacy toward measurable sustainability impact. The growing prominence of blue justice and sustainable finance underscores the normative expansion of Blue Finance, embedding social equity and accountability within its operational logic. Meanwhile, the prominence of blue bonds and water footprint captures the growing alignment of market-based instruments with environmental risk frameworks in advancing sustainable ocean investment.

Collectively, these findings delineate a trajectory from ecological awareness to financial sophistication, mirroring documented trends in sustainability finance toward more operational and resilience-oriented approaches, rather than implying a definitive shift from moral aspiration to adaptive resilience. The resulting conceptual configuration positions Blue Finance as a rapidly consolidating frontier in sustainability science, one that unites ecological responsibility, financial innovation, and policy coherence in designing the next generation of resilient ocean economies. Yet important questions remain regarding the social implications of ocean-resource financialization and the uneven capacity of coastal states to implement complex instruments, underscoring the need for deeper empirical and interdisciplinary inquiry.

Ultimately, the research agenda and emerging challenges outlined for the Blue Finance frontier signal a pivotal shift in sustainability-oriented investment research. Blue Finance appears to be evolving beyond experimental policy instruments into a dynamic platform where innovation, resilience, and sustainability increasingly intersect to redefine ocean governance. The next frontier lies in operationalizing this convergence by translating financial innovation into measurable ecological outcomes, embedding justice and accountability into marine finance systems, and reinforcing adaptive capacity amid climate uncertainty. Advancing this frontier requires an integrative approach that bridges science, finance, and policy, ensuring that Blue Finance evolves not only as an engine of capital mobilization but as a cornerstone of planetary resilience.

6. Conclusions, Implications, and Limitations

6.1. Conclusions

This study provides a comprehensive bibliometric and science-mapping assessment of Blue Finance, illuminating its evolution from a fragmented policy narrative into a structured and rapidly consolidating research frontier. Drawing on 217 publications from 2007 to 2025, the analysis reveals how Blue Finance has matured through three distinct phases of emergence, institutionalization, and interdisciplinary expansion, anchored in sustainability science yet increasingly driven by financial innovation and resilience imperatives.

The conceptual structure of the field is organized around three interlinked thematic axes: the climate–environmental interface, which establishes its ecological foundation; sustainability integration and governance, which embeds transparency, equity, and co-management within financial architectures; and innovative financial mechanisms and economic resilience, which operationalize ecological objectives through blue bonds, Blue Sukuk, and blended finance. Together, these dimensions chart Blue Finance’s transition from normative advocacy to a data-driven, market-aligned paradigm for sustainable ocean investment.

By synthesizing conceptual linkages across ecology, governance, and finance, this research advances a holistic understanding of how Blue Finance functions as both a platform of financial innovation and a catalyst for sustainability transitions. The findings highlight the need for standardized evaluation frameworks, transparent governance mechanisms, and equity-centered policies to ensure measurable ecological and social impact. Further consolidation will depend on the ability to align ecological integrity, financial credibility, and social equity within coherent analytical and operational frameworks. Ultimately, this paper positions Blue Finance as a transformative lever for achieving ocean sustainability, an evolving frontier where innovation, resilience, and responsibility converge to redefine the architecture of sustainable finance.

6.2. Implications for Research, Governance, and Practice

The findings of this study carry broad implications for advancing Blue Finance as a transformative frontier for sustainability, governance, and investment practice. From a research perspective, the results underscore the need to move beyond descriptive mapping toward data-driven, empirically grounded frameworks capable of measuring ecological and socioeconomic impact. Future studies should establish standardized metrics for blue asset pricing, risk-adjusted valuation, and environmental performance to ensure comparability and accountability. Integrating econometric modeling and network-based analysis can further enhance the analytical rigor and policy relevance of Blue Finance research.

From a governance standpoint, institutionalizing transparency, blue justice, and co-management mechanisms remains critical. Strengthening regulatory and verification systems to prevent bluewashing, coupled with embedding climate-risk disclosure standards into financial regulation, will reinforce legitimacy and equity. Governance innovation must ensure that blue finance supports both sustainability and social inclusion.

At the practical level, advancing resilient and inclusive ocean economies demands cross-sectoral collaboration. Partnerships linking policymakers, investors, and coastal communities can catalyze innovation, enhance adaptive capacity, and scale investment in marine resilience. Financial tools, including blue bonds, Blue Sukuk, and blended finance, can serve as catalysts when embedded in transparent, impact-based monitoring frameworks.

Collectively, these implications delineate a strategic direction for Blue Finance as a progressively consolidating interdisciplinary domain where sustainability, innovation, and resilience converge to shape the emerging architecture of ocean investment and sustainable finance. This convergence underscores the need for an integrated theory of Blue Finance that explicitly links environmental risk, governance legitimacy, and financial performance, an area where contributions remain fragmented and where significant potential for high-impact research persists.

6.3. Limitations and Future Research Directions

This study offers a structured overview of the intellectual and thematic evolution of Blue Finance, yet several limitations remain. First, performance and co-word mapping capture conceptual patterns but cannot reflect causal or dynamic relationships among themes. Co-word analysis also assumes equal conceptual weight across Author Keywords, even though heterogeneous terminology, inconsistent author self-labelling, and broad terms like “sustainability” may inflate co-occurrence frequencies and distort cluster prominence. Future studies should consider topic modelling, temporal citation mapping, and mixed-methods meta-analysis to trace thematic evolution more accurately, while semantic text mining, embedding-based NLP, and metadata alignment could harmonize terminology and reduce dependence on author-assigned keywords.

Second, reliance on Scopus-indexed, English-language publications may introduce selection bias and limit regional representation. Broader database coverage and multilingual sources would improve inclusivity. Finally, as this study remains primarily conceptual, combining bibliometric mapping with econometric or case-based evidence would deepen understanding of how Blue Finance instruments translate sustainability goals into measurable outcomes.